Encyclopedia of Sleep and Dreams: The Evolution, Function, Nature, and Mysteries of Slumber 0313386641, 9780313386640

This fascinating reference covers the major topics concerning dreaming and sleep, based on the latest empirical evidence

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Encyclopedia of Sleep and Dreams: The Evolution, Function, Nature, and Mysteries of Slumber
 0313386641, 9780313386640

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The Evolution, Function, Nature, and Mysteries of Slumber

Deirdre Barrett and Patrick McNamara, Editors


Encyclopedia of Sleep and Dreams

' *



Deirdre Barrett and Patrick McNamara, Editors

Q GREENWOOD AN IMPRINT OF ABC-CLIO, LLC Santa Barbara, California • Denver, Colorado • Oxford, England

Copyright 2012 by ABC-CLIO, LLC All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, except for the inclusion of brief quotations in a review, without prior permission in writing from the publisher.

Library of Congress Cataloging-in-Publication Data Encyclopedia of sleep and dreams : the evolution, function, nature, and mysteries of slumber / Deirdre Barrett and Patrick McNamara, editors. 2 v. Includes bibliographical references and index. ISBN 978-0-313-38664-0 (alk. paper) — ISBN 978-0-313-38665-7 (e-ISBN) I. Barrett, Deirdre. II. McNamara, Patrick, 1956[DNLM: 1. Sleep—Encyclopedias—English. 2. Dreams—Encyclopedias—English. 3. Sleep Disorders—Encyclopedias—English. WL 13] 616.8'498003—dc23 2011045470 ISBN: 978-0-313-38664-0 EISBN: 978-0-313-38665-7 16










This book is also available on the World Wide Web as an eBook. Visit www.abc-clio.com for details. Greenwood An Imprint of ABC-CLIO, LLC ABC-CLIO, LLC 130 Cremona Drive, P.O. Box 1911 Santa Barbara, California 93116-1911 This book is printed on acid-free paper (oo) Manufactured in the United States of America

To Ina Livia McNamara on her fourth birthday

Digitized by the Internet Archive in 2020 with funding from Kahle/Austin Foundation



VOLUME I List of Entries, ix Guide to Related Topics, xvii Preface, xxiii Entries, A-L

VOLUME 2 List of Entries, ix Guide to Related Topics, xvii Entries, M-Y Appendix: Additional Resources on Sleep, 813 About the Editors, 849 List of Contributors, 851 Index, 869


List of Entries

Aboriginal Australia: Dreams and “the

Anthropology of Sleep


Antiquity and Dreams


Antrobus’s (1983) Word Information

Actigraphy and Sleep

Count (WIC)

Activation Synthesis Hypothesis of

Art Therapy and Dreams


Asian Americans and Dreamwork

Acute Sleep Deprivation

Asklepieia and Asklepian Rites

Adolescent Cell Phone Use and Sleep

Attention Defecit with Hyperactivity:

Adolescent Dreams

Dreaming in Children with ADHD

Adolescent Sleep, the Electroencephalogram,

Awake, Frozen with the Most Awful

and Brain Development

Fears, but Also Asleep

Adopted Women’s Dreams

Awakenings Protocol

African American Dream Beliefs and

Basics of Sleep Recordings


Bedouin Dream Traditions

Aging and Dreams

Belief in Dream Relevance and the

Alcohol and Sleep

Continuity Hypothesis

Alexithymia and Sleep

Bible and Dreams: Futher and Calvin, The

Alexithymia in Renal Disease

Big Dreams

Ancient Dream Theories

Bizarre Imagery and Thought in Sleep

Ancient Egypt and Dreams

and Waking

Ancient Greek Dream Beliefs

Body Dreamwork

Animal Figures in Dreams

Brain Correlates to Fucidity

Animation and the Dream

Brain Damage: Effects on Dreams

Anthropology and Dreams

Brain Energy, Metabolism, and Sleep




List of Entries Brain Mechanisms of Vision in Dreams

Continuous Positive Airway Pressure

Brief History of Sleep Medicine

(CPAP) Therapy for Obstructive Sleep

Cancer Patients and Dreamwork Central Image (of the Dream) Characters in Dreams

Apnea Convergent Evolution of REM Sleep in Mammals and Birds Cortical EEG Oscillations, Local Sleep,

Children’s Dreams and Nightmares

and Dream Recall

Chinese Sex Symbols in Dreams



Costly Signaling Theory

Church Dream Groups

Counterfactuals in Dreams

Cinema and Dreams

Creative Problem Solving in Dreams

Circadian Rhythms

Cross-Cultural Approaches to Dreams

Clinical Aspects of Nightmares Cognitive Approach to Dreaming Cognitive Expertise and Dreams Cognitive Theory of Dream Meaning, A

Cultural Dimensions of Sleep Cultural Diversity and Dreaming Definition of Sleep Delusions and the Classification of

Coleridge, Samuel Taylor, and Dreaming

Typical Dreams

Color in Dreams

Depictions of Dreams

Comics and Dreams

Depression and Dreaming

Comorbidity between Epilepsy and Sleep

Depression in Patients with Kidney



Comparative Sleep Databases

Depth of Sleep

Comparative Sleep Regulation

Development and Initial Validation of the

Conceptions of Dreaming in the Western

Iowa Sleep Disturbances Inventory

Desert of Australia

Disconnection from the External Envi¬

Connection between Dreams and Mood,

ronment during Dreaming


Discovery of REM Sleep

Consciousness in Dreams Contemporary Theory of Dreaming,

Dissociated States of Being and Agrypnia Excitata


Distinctive Dream Content Associated

Content Analysis of Dreams: Basic

with REM Sleep Behavior Disorder

Principles Continuity Hypothesis and Colors in

Disturbed Sleep and Posttraumatic Stress Disorder


Dream Interview: A Client-Defined,

Continuity Hypothesis of Dreaming

Metaphor-Based Interpretation

List of Entries

Dream Sharing as Social Interaction

Family Unconscious in Dreams

DreamBank.net: An Online Archive for

Fantasy Literature and Dreams

Studying Dream Content

Fetal Sleep

Dreaming: The Journal of the Association

Fetal Yawning

for the Study of Dreams Dream-Lag Effect

Flying Dreams Flying in Dreams: The Power of the

Dreamwork in Counseling


Dynamic Structure of Reptilian EEG

Fornari, Franco

versus Mammalian Sleep EEG Ecstasy (MDMA) Use and Sleep Problems

Freud, Sigmund Freud’s Approach to Dreams Functional Neuroimaging during Human

Effect of Dreams on Waking Life


Effect of Medications on Sleep and

Functional Theories of Dreaming

Dreaming Effects of Blindness and Deafness on Dream Content

Gender Differences in Dreaming Genetics and Epigenetics of Sleep Genetics of Mouse Sleep Physiology

Effects of Work on Sleep Gestalt Dreamwork Electromagnetic Fields of Mobile Telephones and Sleep Parameters Embodied Imagination Emotional Responses to Nightmares Endocrinology of Sleep

Graphic Novels and Dreams Group Work with Dreams Hall and Van de Castle System for the Study of Dream Content Handedness: A New Look at the Effects

Endometriosis and Dreams

on Dream Recall and Content

ESP in Dreams

Healing and Dreams

Evaluation of Tonsils in Patients with

Hill Dream Model

Sleep Apnea Evolution of Reptilian Sleep

Hypnagogic Imagery Hypocretin Gene Transfer in Mice

Evolutionary Approaches to Sleep

Models of Narcolepsy

Evolutionary Psychology Theories of



(HPA) System and Sleep

Existential Dreams


External Sensory Stimulation as a

(HPS) System and Sleep

Technique to $tudy Dreaming

Illness and Dreams

False Awakenings

Illusory Contents in Dreams





List of Entries

Impactful Dreams

Media Use and Nightmares

Importance of Sleep Health for Children

Media Use and Sleep in Children and

Increasing Sleep Complaints


Incubation of Dreams

Medications Altering Dreaming


Medieval Hagiography and Dreams

Infant Sleep and Parenting

Melatonin Therapy for the Sleep

Infant Sleep Interventions Insomnia in Chronic Renal Failure International Association for the Study of Dreams Intersubjective Dreams Intuition in Dreams Involuntary Nature of Dreaming Islam and Dreams Isolated Sleep Paralysis

Disorders of Children Methodological Challenges in the Scientific Study of Dreams Middle Ages and Dreams Mugwort: A Dream-Stimulating Herb Music and Dreams Naps Narcolepsy and Dreaming Narcolepsy and Sleep Paralysis, Hypnopompic/Hypnagogic Hallucinations

Istikhara: Islamic Dream Incubation Journaling of Dreams Jung’s Dream Theory Jung’s The Red Book Jung’s Transcendent Function: Neurological Support Kleine-Levin Syndrome

Narcolepsy Symptoms, Abnormal REM Sleep, and Hypocretin Deficiency Native American Dreams Neural Metaphor and Dreams Neuroanatomical Correlates of Dream Censorship Neuroanatomical Correlates of

Leading Dream Groups


Literature and Dreams

Neuroanatomy of Dreams

Little Dreams

Neuroanatomy of REM Sleep and

Logical Structure of Dreams and Their


Relation to Reality Lucid Dreaming

Neurobiology of Psychoanalysis in Wake and REM Sleep

Lucid Dreaming in Sports

Neurofeedback for Sleep Problems

Lucid Dreaming Therapy for Nightmares

Neuropsychology of Lost Dream Recall

Lucid Nightmares

Nightly Sleep Duration and Mortality:

Meaning of Dreams via Dream

The Story of a U-Shaped Relationship


Nightmare Content in Adults

List of Entries


Recall of Dreams

Objective and Subjective Dreams

Regulation of Sleep and Wake Systems

Obstructive Sleep Apnoea, Metabolism,

Religion and Dreams

and Hormones

REM-NREM Dream Content

Olfactory Stimuli and Dreams


Overgeneral Memories

REM Sleep across the LifeSpan

Parapsychology and Dreams

REM Sleep Behavior Disorder

Parasomnias and Nocturnal Frontal Lobe


REM Sleep Properties

Epilepsy Partial Sleep Deprivation Phasic Ponto-Geniculo-Occipital/ Pontine Wave (PGO/P-Wave) Philosophy of Mind and Dream Characters Photography and Dreams Phylogenetic Comparative Methods and

REM Sleep Properties as Neurobiological Endophenotypes of Schizophrenia REM Sleep-Related Motor Paralysis Reverse Learning Theory Role of Subcortical Structures in Dreaming Safety in Dream Groups


School of Metaphysics Approaches to

Phylogeny of Sleep

Dream Incubation

Phylogeny of Sleep Database

Seasonal Affective Disorder in Sleep

Pittsburgh Sleep Quality Index

Self-Assessment Tools of Circadian

Play and the Dream

Typology in Children, Adolescents, and Adults

Poetry and Dreams Portable Monitoring of Sleep Precognitive Dreaming Prefrontal Cortex in Dreaming Pregnancy Dreams Primary Disorders of Hypersomnolence and Dreams Psychiatric Diagnosis and Dreams Quaker Culture and Dreams Quality of Life and Sleep Disorders in

Self-Consciousness and Dreaming Self in Dreams, The Self-Organization from Chaos in Dreams Selfscape Dreams Serotonin in the Regulation of REM Sleep Sexual Dreams: Meaning and Practical Insight Shakespeare and Dreams

Chronic Kidney Disease

Shamanism and Dreams

Qur’an and Dreams

Short Sleep

Rapid Eye Movement Sleep in Critically

Significance of Dreams in Western

Ill Patients

Australian Desert Aboriginal Worldview


List of Entries

Sleep and Arthritis Sleep and Bird Songs Sleep and Brain Networks Sleep and Cardiometabolic Risk Sleep and Culture Sleep and Dreams in Psychiatric

Sleep EEG across Adolescent Development Sleep Fragmentation Sleep in Adolescents Sleep in Aquatic Mammals Sleep in Children with Cancer

Disorders and Autism

Sleep in Disorders of Consciousness

Sleep and Dreams in Western Antiquity

Sleep in Insects

Sleep and Evolution of Detailed Focal

Sleep in Patients with Alzheimer’s



Sleep and Growth Hormone Release

Sleep in Patients with Parkinson’s

Sleep and Mild Cognitive Impairment Sleep and Obesity Sleep and Shift Work Sleep and Suicide Sleep and the Endocrine System Sleep and the Generation of New Nerve Cells in the Adult Brain Sleep and the Metabolic Syndrome Sleep and Thermoregulation Sleep Apnea in Heart Failure

Disease Sleep in Patients with Wilson’s Disease Sleep, Inflammation, and Cardiovascular Disease Sleep Intensity and the Homeostatic Regulation of Sleep Sleep, Memory, and Dreams Sleep, Nightmares, and Psychiatry Sleep Pattern and Its Determining Factors in University Students Sleep Patterns in Patients with Acute

Sleep as We Age

Coronary Syndromes

Sleep Development in Infancy and Early

Sleep, Plasticity, and Metaplasticity


Sleep Problems among Veterans of

Sleep Diaries

Foreign Wars

Sleep Disordered Breathing in Teenagers

Sleep, Psychiatric Disorders, and the

Sleep Disorders and Dreaming

Transdiagnostic Perspective

Sleep Disorders in Patients with Chronic

Sleep Quality: A Behavioral Genetic

Kidney Disease


Sleep Disorders in Patients with Heart Failure

Sleep-Related Hallucinations and Ghost Tales

Sleep Disturbances in Posttraumatic

Sleep-Related Mental Activities in

Stress Disorder (PTSD)

Insomnia: Role and Assessment

Sleep, Dreams, and Personality

Sleep Spindles

Sleep, Dreams, and the Time Sense

Sleep Talking

List of Entries

Sleep Variables and Handedness:

Teaching Courses on Dreams

Methodological Issues and State

Teaching Dreams via Dream Lab

of the Field Sleepiness and Driving Sleeping and Dreaming Patterns in the Context of Attachment Relationships Social Network Analysis of Dream

Television Consumption and Dreaming Theoretical Models and Neural Basis Theory of Mind and Dreaming Threat Simulation Theory


Traditional Korean Dreams

Sound-Work: The Neglected Sense

Traffic Noise and Autonomic Arousals

in Working with Dream Images

during Sleep

Space in Dreams

Transcendent Dreams

Sports and Dreaming

Trauma Treatment and Dreams

Stage behind the Eyes—Theatre

Types of Consciousness in Dreams

and Dreams

Ullman Method of Group Dreamwork

Stages of Sleep and Associated

The Unconscious and Dreams before



Structural Analysis of Dream Narratives

Use of Noninvasive Techniques in the

Subjective Experience across States

Study of Dreaming

of Sleep and Wakefulness

Using Dreams in Cognitive-Behavioral

Sumerian Dream Beliefs


Survivors of the Holocaust and Rwandan

Video Game Play and Dreams

Genocide: Dream Accounts

Visual Art and Dreams


White Noise and Sleep

Tarotpy Method

Women’s Dreams across the Life Cycle

Tau Protein and Sleep-Wake Cycle




Guide to Related Topics

Many of the cross references that appear


after the entries refer to the following top¬

African American Dream Beliefs and Practices

ics and their related entries. For example,

Ancient Egypt and Dreams

after the “Achuar” entry: See also: entries

Anthropology and Dreams

related to Cross-Cultural Dreams.

Asian Americans and Dreamwork Bedouin Dream Traditions

Animal Sleep

Conceptions of Dreaming in the Western Comparative Sleep Regulation

Desert of Australia

Sleep and Bird Songs


Sleep in Aquatic Mammals

Cross-Cultural Approaches to Dreams

Sleep in Insects

Cultural Diversity and Dreaming Native American Dreams

Brain Stimulation

Quaker Culture and Dreams Shamanism and Dreams

External Sensory Stimulation as a

Significance of Dreams in Western

Technique to Study Dreaming

Australian Desert Aboriginal

Use of Noninvasive Techniques in the


Study of Dreaming

Traditional Korean Dreams

Comparative Sleep Databases Comparative Sleep Databases

Dream Content

Phylogeny of Sleep Database Animal Figures in Dreams Central Image (of the Dream)

Consciousness and Dreams

Characters in Dreams Cognitive Expertise and Dreams

Color in Dreams

Consciousness in Dreams

Content Analysis of Dreams: Basic

Self-Consciousness and Dreaming

Principles Counterfactuals in Dreams

Cross-Cultural Dreams

Delusions and the Classification of Typical Dreams

Aboriginal Australia: Dreams and “the

Depictions of Dreams

Dreaming” xvii



Guide to Related Topics

DreamBank.net: An Online Archive for Studying Dream Content Endometriosis and Dreams ESP in Dreams Existential Dreams

Dreams and Art Photography and Dreams Visual Art and Dreams

Dreams and Creativity

Flying Dreams Hall and Van de Castle System for the Study of Dream Content

Creative Problem Solving in Dreams Synesthesia

Impactful Dreams Intuition in Dreams

Dreams and Development

Nightmare Content in Adults

Adolescent Dreams

Olfactory Stimuli and Dreams

Children’s Dreams and Nightmares

REM-NREM Dream Content Specializations Selfscape Dreams Sleep, Dreams, and the Time Sense Sound-work: The Neglected Sense in Working with Dream Images Space in Dreams Structural Analysis of Dream Narratives Theory of Mind and Dreaming Transcendent Dreams

Dream Properties

Dreams and Fiction/Literature Fantasy Literature and Dreams Graphic Novels and Dreams Literature and Dreams Middle Ages and Dreams Poetry and Dreams Shakespeare and Dreams

Dreams and Memory Dream-Lag Effect Overgeneral Memories

Involuntary Nature of Dreaming Play and the Dream

Dream Theories Belief in Dream Relevance and the Conti¬ nuity Hypothesis Cognitive Theory of Dream Meaning, A Contemporary Theory of Dreaming, The Continuity Hypothesis of Dreaming

Dreams and Movies Animation and the Dream Cinema and Dreams Media Use and Nightmares Media Use and Sleep in Children and Adolescents Stage behind the Eyes—Theatre and Dreams

Functional Theories of Dreaming Illusory Contents in Dreams

Dreams and Religion

Jung’s Dream Theory Jung’s The Red Book Jung’s Transcendent Function: Neurological Support Neural Metaphor and Dreams Self-Organization from Chaos in Dreams

Bible and Dreams: Luther and Calvin Islam and Dreams Qur’an and Dreams

Dreams and Therapy

Teaching Dreams via Dream Lab

Art Therapy and Dreams

Threat Simulation Theory

Body Dreamwork

Guide to Related Topics

Cancer Patients and Dreamwork


Genetics of Sleep

Cognitive Approach to Dreaming Dreamwork in Counseling Embodied Imagination Gestalt Dreamwork Hill Dream Model

Genetics and Epigenetics of Sleep Genetics of Mouse Sleep Physiology

Infant Sleep Interventions Intersubjective Dreams Neuroanatomical Correlates of Dream Censorship

History of Dreams/Sleep Ancient Dream Theories Ancient Greek Dream Beliefs

Neuroanatomical Correlates of Dreamwork

Antiquity and Dreams

Neurofeedback for Sleep Problems

Bible and Dreams: Luther and

Objective and Subjective Dreams


Ullman Method of Group Dreamwork

Brief History of Sleep Medicine

Using Dreams in Cognitive-behavioral

Fornari, Franco


Dreams and Trauma Dream Accounts by Survivors of the Holocaust and Rwandan Genocide Trauma Treatment and Dreams

Evolution of Sleep Convergent Evolution of REM Sleep in Mammals and Birds

Freud, Sigmund Freud’s Approach to Dreams Incubation of Dreams Incubus/Succubus Medieval Hagiography and Dreams Religion and Dreams Sleep and Dreams in Western Antiquity Sumerian Dream Beliefs

Costly Signaling Theory Evolutionary Approaches to Sleep Evolutionary Psychology Theories of Dreams Phylogenetic Comparative Methods and Sleep Phylogeny of Sleep

Experimental Methodologies for Studying Dreams Awakenings Protocol Dream Interview: A Client-Defined, Metaphor-Based Interpretation Methodological Challenges in the Scientific Study of Dreams

Hormones in Sleep Endocrinology of Sleep Hypothalamo-Pituitary-Adrenocortical (HPA) System and Sleep Hypothalamo-Pituitary-Somatotrophic (HPS) System and Sleep Sleep and Growth Hormone Release Tau Protein and Sleep-Wake Cycle

Individual Differences in Dreaming Adopted Women’s Dreams Connection between Dreams and Mood, The Gender Differences in Dreaming

Fetal Sleep Fetal Sleep Fetal Yawning

Handedness: A New Look at the Effects on Dream Recall and Content Recall of Dreams




Guide to Related Topics

Infant Sleep

Reptilian Sleep

Infant Sleep and Parenting

Dynamic Structure of Reptilian EEG

Infant Sleep Interventions

versus Mammalian Sleep EEG Evolution of Reptilian Sleep

Lucid Dreaming Brain Correlates to Lucidity

Sex and Dreams

Lucid Dreaming

Chinese Sex Symbols in Dreams

Lucid Dreaming in Sports

Sexual Dreams: Meaning and

Lucid Dreaming Therapy for Nightmares

Practical Insight

Lucid Nightmares

Sleep and Culture Metabolic Syndrome Actigraphy and Sleep

Cultural Dimensions of Sleep Sleep and Culture

Antrobus’s (1983) Word Information Count (WIC)

Parapsychology and Dreams Parapsychology and Dreams

Sleep and Development Sleep Development in Infancy and Early Childhood Sleep in Adolescents

Precognitive Dreaming

Sleep and Emotion Parasomnias Dissociated States of Being and Agrypnia

Alexithymia and Sleep Partial Sleep Deprivation

Excitata Parasomnias and Nocturnal Frontal Lobe Epilepsy

Philosophy of Dreams Philosophy of Mind and Dream Characters Self in Dreams, The

Sleep and Health Alcohol and Sleep Importance of Sleep Health for Children Short Sleep Sleep, Psychiatric Disorders, and the Transdiagnostic Perspective Sleep Disorders in Patients with Heart

PTSD and Dreams/Sleep Disturbed Sleep and Posttraumatic Stress Disorder

Failure Sleep Patterns in Patients with Acute Coronary Syndromes

Sleep Disturbances in Post-Traumatic Stress Disorder (PTSD)

REM Sleep Brain Mechanisms of Vision in Dreams

Sleep and Renal Disease Alexithymia in Renal Disease Depression in Patients with Kidney Disease

REM Sleep across the Lifespan

Insomnia in Chronic Renal Failure

REM Sleep Properties

Quality of Life and Sleep Disorders in

REM Sleep-Related Motor Paralysis

Chronic Kidney Disease

Guide to Related Topics

Sleep Disorders in Patients with Chronic


Sleep Deprivation

Kidney Disease Acute Sleep Deprivation

Sleep and the Brain

Rapid Eye Movement Sleep in Critically Ill Patients

Functional Neuroimaging during Human

Sleep and Shift Work

Sleep Prefrontal Cortex in Dreaming

Sleep Disorders

Sleep and Brain Networks Stages of Sleep and Associated Waveforms

Attention Defecit with Hyperactivity: Dreaming in Children with ADHD Depression and Dreaming

Sleep Apnea

Hypocretin Gene Transfer in Mice Models of Narcolepsy

Continuous Positive Airway Pressure (CPAP) Therapy for Obstructive Sleep Apnea Evaluation of Tonsils in Patients with Sleep Apnea Obstructive Sleep Apnoea, Metabolism, and Hormones

Isolated Sleep Paralysis Medications Altering Dreaming Narcolepsy and Dreaming Narcolepsy and Sleep Paralysis, Hypnopompic/Hypnagogic Hallucinations Narcolepsy Symptoms, Abnormal REM Sleep, and Hypocretin Deficiency Psychiatric Diagnosis and Dreams

Sleep Assessment Pittsburgh Sleep Quality Index Portable Monitoring of Sleep Self-Assessment Tools of Circadian Typology in Children, Adolescents, and Adults Sleep Diaries

REM Sleep Behavior Disorder REM Sleep Behavior Disorder and Dreams REM Sleep Properties as Neurobiological Endophenotypes of Schizophrenia Seasonal Affective Disorder in Sleep Sleep, Nightmares, and Psychiatry Sleep and Suicide

Sleep Biology Definition of Sleep Depth of Sleep Phasic Ponto-Geniculo-Occipital/Pontine Wave (PGO/P-Wave) Sleep, Inflammation, and Cardiovascular Disease Sleep and Cardiometabolic Risk Sleep and Evolution of Detailed Focal

Sleep Disorders and Dreaming Sleep Fragmentation Sleep in Patients with Alzheimer’s Disease Sleep in Patients with Parkinson’s Disease Sleep in Patients with Wilson’s Disease Sleep Problems among Veterans of For¬ eign Wars Sleep-Related Hallucinations and Ghost Tales

Vision Sleep Spindles Sleep Variables and Handedness: Methodological Issues and State of the Field

Sleep Physiology Awake, Frozen with the Most Awful Fears, but Also Asleep




Guide to Related Topics

Disconnection from the External Environ¬ ment during Dreaming REM Sleep across the Lifespan Serotonin in the Regulation of REM Sleep Sleep Intensity and the Homeostatic Regulation of Sleep

Social Psychology of Dreams Church Dream Groups Group Work with Dreams Journaling of Dreams Leading Dream Groups Safety in Dream Groups Social Network Analysis of Dream Content

Sleep-Wake Continuum Bizarre Imagery and Thought in Sleep and Waking Logical Structure of Dreams and Their Relation to Reality Subjective Experience across States of Sleep and Wakefulness

Teaching Courses on Dreams Television Consumption and Dreaming

Theories of Sleep Activation Synthesis Hypothesis of Dreaming Reverse Learning Theory

M Meaning of Dreams via Dream

This method has been found to be effec¬


tive (DeCicco, 2007a) and leads dream¬ ers to discovery through group work that

One of the most practical, important, and

could be otherwise difficult to establish on

valuable aspects of dreams is that people

their own (Wolman & Ullman, 1986). A

can draw meaning from their dreams via

third example is the Gestalt method, which

dream interpretation. It has been found that

is one where dreamers are guided to fully

dream interpretation can aid in the process

integrate the dream material via engag¬

of insight (Pesant & Zadra, 2004), can pro¬

ing in the bodily feelings and actions of

vide a means to explore emotions (Goelitz,

the dream (Pesant & Zadra, 2004). There

2001), can help decrease psychological dis¬

are many therapist-assisted techniques for

tress (Crook & Hill, 2003; Pesant & Zadra,

dream interpretation that are widely used

2004), help with feelings of isolation,

around the world and have merit in various

lack of support, life transition issues, and

situations and environments.

provide effective coping strategies (De-

Self-guided techniques (DeCicco, 2009)

Cicco, 2007a, 2007b, 2009; DeCicco &

are first taught by a therapist or work¬

Higgins, 2009). Meaning and insights are

shop leader with detailed instructions and

gained with a variety of methods, which

are then carried out by dreamers on their

generally fall into one of two categories:

own. Examples of these techniques are

(1) therapist-assisted methods of interpre¬


tation and (2) self-guided techniques.

interpretation (DeCicco, 2007b, 2009), the

storytelling method (TSM) of dream

Therapist-assisted techniques are used

dream interview method (DIM; Delaney,

in therapy sessions or in groups with a

1993), and meditative dream reentry (MDR;

therapist who guides or directs the tech¬

DeCicco, 2009). TSM provides dreamers

nique. One such technique is a cognitive-

with a worksheet that guides them from the

experiential method designed by Dr. Clara

dream, through associations, story-making,

Hill (Hill, 2003; Hill & O’Brien, 1999).

and finally, to the insight relating to wak¬

The method is therapist assisted with

ing life. The DIM is a contemporary method

three stages of interpretation: the explora¬

developed by Delaney (1993) and involves

tion, insight, and action stages. A second

the dreamer as the interpreter and has been

very successful and widely used method

shown to be successful in practice (Flow¬

is the Ullman method (Ullman & Zim¬

ers & Zweben, 1996). The third example,

merman, 1979), which employs the use

MDR, is one that combines relaxation train¬

of a group setting to create safety while

ing, guided imagery, and drawing therapy

leading dreamers to discovery or insight.

to aid in tapping into the deepest level of




Meaning of Dreams via Dream Interpretation

meaning of dreams—long-forgotten mem¬


ories and emotional shifting. The method

Crook, R.E., & Hill, C.E. (2003). Working with dreams in psychotherapy: The thera¬ pists’ perspective. Dreaming, 13(2), 83-96.

has been proven to be successful and is es¬ pecially applicable for dreams with negative imagery or emotions (DeCicco, 2009). Selfguided dream-interpretation techniques are generally user friendly, practical, and sci¬ entifically proven to lead dreamers to in¬ sight or discovery. Furthermore, they can be used in a formal therapy environment along with other therapeutic techniques (e.g., cognitive-behavioral therapy). Dream interpretation has been proven to be beneficial and effective in past re¬ search for those recovering from trauma, for nightmare treatment, for patients with depression and anxiety, for coping with

DeCicco, T.L. (2007a). Dreams of female university students: Content analysis and relationship to discovery via the Ullman method. Dreaming, 17(2), 98-112. DeCicco, T.L. (2007b). What is the story tell¬ ing? Examining discovery with the story¬ telling method (TSM) and testing with a control group. Dreaming, 17, 227-237. DeCicco, T.L. (2009). The giant compass: Navigating your life with your dreams.

North Carolina: Malito Press. DeCicco, T.L., & Higgins, H. (2009). The dreams of recovering alcoholics: Mood, dream content, discovery, and the storytell¬ ing method of dream interpretation. Inter¬

cancer, for treating patients with addic¬

national Journal of Dream Research, 2(2),

tions, with neurogenic communication dis¬


orders, issues of family attachment, and fear and loss (see, e.g., DeCicco, 2007a; Eigen, 2004; Mellman,

David, Busta¬

mante, Torres, & Fins, 2001). Various tech¬ niques have also been found useful for those caring for the dying, coping with stressful life events, and for aiding in the develop¬ mental process of fully becoming one’s self (Wadensten, 2009). Lastly, dream interpre¬ tation has been found to be applicable for

Delaney, G. (1993). The dream interview. In G. Delaney (Ed.), New directions in dream interpretation (pp. 195-240). Albany: State University of New York Press. Eigen, M. (2004). Alone with God. Journal of Religion and Health, 43(3), 185-200. Flowers, L. K., & Zweben, J.E. (1996). The changing role of “using” dreams in addic¬ tion recovery. Journal of Substance Abuse Treatment, 15, 193-200.

of finding meaning in dreams with various

Goelitz, A. (2001). Nurturing life with dreams: Therapeutic dream work with cancer pa¬ tients. Clinical Social Work Journal, 29(4), 375-388.

methods. This is an important component

Hill, C.E. (2003). Working with dreams: Fa¬

of dream interpretation as it ensures that the

cilitating exploration, insight, and action.

methods are reliable and valid. Furthermore,

Washington, DC: American Psychological Association.

groups, couples, children, and adults. Cur¬ rent research continues to explore the value

dream-interpretation methods are being translated and tested in various languages other than English to make them widely accessible around the world (e.g., TSM— Italian version, TSM—Spanish version). Teresa L. DeCicco

Hill, C.E., & O’Brien, K. (1999). Working with dreams in psychotherapy. New York: Guil¬ ford Press. Mellman, T.A., David, D., Bustamante, V., Torres, J., & Fins, A. (2001). Dreams in the acute aftermath of trauma and their

Media Use and Nightmares

relationship to PTSD. International So¬ ciety for Traumatic Stress Studies, 74(1), 241-253. Pesant, N., & Zadra, A. (2004). Working with dreams in therapy: What do we know and what should we do? Clinical Psychology Review, 24, 489-512.


had not been exposed (Dworak, Schierl, Bruns, & S trader, 2007). This exposure ex¬ periment was very modest as the average young person is exposed to much more on a daily basis, often without any cooling-off period. The true impact of the excitement

Ullman, M., & Zimmerman, N. (1979). Work¬ ing with dreams. New York: Dellacorte Press.

caused by media content in natural settings

Wadensten, B. (2009). Older people’s experi¬ ence of dream coaching. Journal of Holistic Nursing, 27(4), 266-275.

to average media content. Research by

Wolman, B., & Ullman, M. (1986). Handbook of states of consciousness. New York: Van Nostrand Reinhold Company.

may therefore be much bigger. Children are, however, not only exposed Joanne Cantor (1998) has shown that ex¬ posure to scary films and TV content may lead to enduring fright reactions, even for decades after exposure. The news, too, is a source of scary images. The events of Sep¬ tember 11, 2001, for instance, have been shown to lead to posttraumatic stress disor¬

Media Use and Nightmares

ders and to recurring nightmares in children exposed to news about the events (Propper,

The greatest concern about the potential

Stickgold, Keeley, & Christman, 2007).

impact of the media on sleep is whether

A cross-sectional study of 2,500 Flem¬

media use displaces sleep. Television

ish children (Van den Bulck, 2004) showed

viewing, computer game play, or listening

that 33 percent of them had frequent night¬

to music—to name just those—are so ap¬

mares about TV content. Nightmares about

pealing that they vie for young people’s at¬

computer games were reported by 10 per¬

tention at the detriment of sleep time.

cent of the boys and 5 percent of the girls.

Even after the use of the media is aban¬

These findings were not limited to the

doned and sleep finally prevails, the impact

heavy users of the media—they occurred

of the media on sleep does not end. Media

at all levels of media use.

use may affect sleep quality as media con¬ tent may invade dreams.

Future research should study mediainduced nightmares with more valid instru¬

Even though little research has been

ments than self-reports, which are prone

done about this subject, a number of con¬

to over- and underreporting. Charting of

clusions can be drawn from existing stud¬

nightmares may reveal which types of

ies. In one study, school children were

content are most likely to lead to such re¬

exposed to television, to computer games,

actions. Because some images produce

or to a movie shortly before bedtime. Even

trauma-like responses, it may be impor¬

though a two- to three-hour cooling-off

tant to examine whether media nightmares

period was included, sleep was disturbed

need to be countered in a particular way.

in the children who had been exposed to

Finally, it is important to note that the

the media compared to a control group that

study of Flemish children quoted previously




Media Use and Sleep in Children and Adolescents

(Van den Bulck, 2004) also showed that

growth, behavioral development, and emo¬

more than half of the children reported

tional regulation. Specifically, insufficient

pleasant dreams induced by the various

sleep and poor sleep quality can result in

media. Coupled with research on the mood¬

a profound negative consequence in chil¬

enhancing properties of the media, this sug¬

dren and adolescents: first and above all,

gests that it is worth examining whether the

decreased concentration, impaired mem¬

processes leading to nightmares may also be

ory performance, and therefore poor aca¬

employed to improve sleep.

demic performance, followed by increased

Jan Van den Bulck See also: Nightmares

aggression and behavioral problems, de¬ creased reaction time and increased vul¬ nerability to injury, and, according to more


recent research, disordered energy regula¬

Cantor, J. (1998). “Mommy I’m scared”: How

tion, and increased obesity.

TV and movies frighten children and what

While the evidence for the importance

we can do to protect them. San Diego, CA:

of sleep and an association between poor

Harcourt Brace & Company. Dworak, M., Schierl, T., Bruns, T., & Striider, H. K. (2007). Impact of singular excessive computer game and television exposure on sleep patterns and memory performance of school-aged children. Pediatrics, 120, 978-985. Propper, R. E., Stickgold, R., Keeley, R., & Christman, S.D. (2007). Is television trau¬ matic? Dreams, stress, and media exposure in the aftermath of September 11,2001. Psy¬ chological Science, 18, 334-340. Van den Bulck, J. (2004). Media use and dreaming: The relationship among televi¬ sion viewing, computer game play, and nightmares and pleasant dreams. Dream¬ ing, 14, 43-49.

sleep and their negative consequences are becoming quite impressive, it is demon¬ strated that sleep duration among children and adolescents has decreased by approxi¬ mately 1 hour over the past 10 years and 1.5 to 2 hours over the past 50 years. These findings trigger the heightened concern on the impacts of rapid social development and technology evolution on children’s and adolescents’ sleep behaviors. According to the National Sleep Foun¬ dation’s 2006 Sleep in America Poll (2006), the majority of American schoolaged children and almost all adolescents had at least one electronic media device, such as bedroom television, videogames, mobile telephone, computer, Internet ac¬

Media Use and Sleep in Children and Adolescents

cess, and music player. Even in develop¬ ing countries, with the ongoing economic development, media devices have become

During recent decades, accumulating re¬

commonplace for children and adoles¬

searches reveal the importance of sleep

cents in urban areas. An increasing num¬

on human-health being. In children and

ber of studies consistently demonstrate

adolescents, sleep is considered particu¬

that media use has become an influential

larly crucial for learning and memory, as

factor in children’s and adolescents’ sleep.

well as having implications for physical

Among all of the previously mentioned

Media Use and Sleep in Children and Adolescents


media devices, television is the most pop¬

than one to two hours of quality program¬

ular and widely used. Therefore, our dis¬

ming per day. Furthermore, consistent with

cussion will begin with television.

common bedtime hygiene recommenda¬ tions, television sets should be removed from children’s bedrooms.

Television Viewing and Sleep It was reported that 98 to 100 percent of children and adolescents watch television in developed countries, with the average

Video/Computer Game Playing and Sleep

viewing time ranging from 6.3 to 15.4

Regarding video/computer game playing,

hours per week by different cultural back¬

their rapid popularity took place during

grounds and different age groups.

the past two decades in line with the inno¬

There is a general and clear recognition

vation and improvement of gaming tech¬

that television viewing has a negative im¬

nology. According to the National Sleep

pact on children’s and adolescents’ sleep,

Foundation’s 2006 Sleep in America Poll,

although little consensus regarding which

approximately half and one third of adoles¬

aspects of sleep may be related to televi¬

cents had their own videogames and com¬

sion viewing has been achieved. The most

puter/Internet access, respectively.

consistent results seem to be shorter sleep

Similar to television viewing, video/

duration, prolonged sleep-onset latency,

computer game playing has been associ¬

and delayed bedtime. In addition, there

ated with later bedtime, longer sleep-onset

is growing evidence that sleep disorders

latency, and shorter sleep duration. More¬

involving bedtime resistance, sleep anx¬

over, experimental research demonstrated

iety, parasomnia, and less often sleep-

that exposure to videogames for two to

disordered breathing are also related to

three hours prior to bedtime could change

television viewing. Interestingly, a study

sleep architecture, with less time spent in

found that, similar to television viewing,

slow-wave sleep, consequently resulting

passive television exposure during waking

in poor sleep quality and daytime sleepi¬

hours also had negative impacts on chil¬

ness. With respect to sleep disorders, a few

dren’s sleep, including decreased sleep

studies showed that video/computer game

duration and difficulties in initiating and

playing was linked to sleep latency and

maintaining sleep. In terms of television

subjective insomnia (see Figure 15).

viewing during daytime, in the evening, or at bedtime, we must emphasize the hazards of television viewing in the evening, espe¬ cially at bedtime. Taken together,

Mobile Telephone Use and Sleep With the rapid improvement in technol¬


ogy, mobile telephone usage increasingly

among children and adolescents should be

extends its functioning from the simple,

restricted, especially at bedtime. In 2001,

such as for making and receiving calls

the American Academy of Pediatrics rec¬

and text messaging, to the varied, such

ommended that children watch no more

as for entertainment, including playing





Media Use and Sleep in Children and Adolescents

Possible Mechanism? . Shortening Sleep Duration

• Later Bedtime

• Increasing Arousal Level

• Short Sleep Duration

• Altering Sleep Architecture

• Increased Sleep Problems

• Delaying Circadian Rhythm

Figure 15: The Potential Impact of Media Using on Sleep. Courtesy Shenghui Li.

games, listening to music, and accessing

a sleep aid among children and adoles¬

the Internet. In line with the functioning

cents. More research is needed to assess

development and widespread use, mobile

the positive and negative effects of music

phones have been considered a risk fac¬

on sleep—and the effects of different types

tor in children’s and adolescents’ sleep.

of music on sleep.

Although far from clear and without defi¬ nite results, several studies provided pre¬ liminary evidence that mobile phone use

Potential Mechanism

was associated with delayed sleep-wake

There are several hypotheses that have

cycle and disrupted sleep. Moreover, a re¬

been proposed regarding the potential

cent study in Sweden found a borderline

mechanisms of association between media

significant relationship between daytime

use and sleep. First, media use as a form

tiredness and mobile phone use. Given the

of unstructured activity, which usually

wide-ranging functioning and its portabil¬

lacks a clear beginning and end, is likely

ity, mobile phones could become the most

to be easily extended, leading to sacrifice

frequently used media device. More and

of sleep time, thus shortening sleep dura¬

further research is needed to specifically

tion. Second, exposure to the bright light of

and accurately clarify the impact of mobile

the viewing screen before sleep may affect

phone usage on sleep.

the sleep/wake cycle through suppression

Apart from television, video/computer

of the nocturnal salivary secretion of mela¬

games, and mobile phones, music players

tonin and consequently delay the circadian

also have been widely used. Surprisingly,

rhythm. Third, media use may increase the

the effect of music on the sleep of children

activity level of the nervous system and

and adolescents has rarely been studied. To

result in heightened alertness, physiologi¬

the best of our knowledge, only two stud¬

cal arousal, and difficulty in falling asleep.

ies explored the effectiveness of music as

It has been reported that there is a dose-

Medications Altering Dreaming


response relationship between light inten¬

dreaming had significant research advan¬

sity and human alertness. Finally, media

tages since dreaming/REM sleep could

use as a form of sedentary activity also may

be studied in animal models so that the

alter sleep architecture and lead to poor-

REM sleep-dreaming correlate became

quality sleep.

the routine approach utilized in studying dreaming in both animal models as well as in human subjects. REM sleep is con¬


trolled based on the interplay between two

It appears that the use of electronic media

major neuromodulator systems (aminergic

by children and adolescents does have a

and cholinergic) in the brainstem. More

negative impact on their sleep, although

recent versions of this once-simple sys¬

the precise effects and mechanisms remain

tem, now called AIM (activation, input,

unclear. Based on the previous clarifica¬

modulation), have become increasingly

tion, use of media devices, especially at

complex as other neurotransmitters and

bedtime, should be restricted. Particularly,

neuromodulators, including GABA, gluta¬

and most importantly, guidelines concern¬

mate, and glycine, histamine, nitric oxide,

ing the hygiene of electronic media use at

adenosine, dopamine, and other less well-

bedtime should be developed and tailored

described neuropeptides have been shown

for specific age groups of children and

to affect REM-sleep generation (Hobson,


Pace-Schott, & Stickgold, 2003, pp. 1-50). Shenghui Li

See also: Increasing Sleep Complaints

More recently, studies utilized data as to the reported effects of medications on dreaming derived from the clinical trials


required for the use and release of new

National Sleep Foundation. (2006). 2006 Sleep in America poll. Washington, DC: Author.

agents, as well as physician reports of ad¬ verse medication side effects. These stud¬ ies were carried out in human beings, the only species that can currently report both

Medications Altering Dreaming

the content and an experience of whether a dream has occurred. These data indicate that the medications that alter dreaming

A wide variety of prescriptive and supple¬

differ from those known to affect REM

mentary medications are reported to af¬

sleep with REM-sleep-suppressant medi¬

fect dreaming and/or induce nightmares.

cations inducing disturbed dreaming and

Until recently, studies addressing medi¬


cation effects on dreaming focused on

the primary REM-sleep neuromodulator,

those neurochemicals known to affect

acetylcholine, having minimal effects on

REM sleep based on the belief that these

dreaming. The group of pharmacological

medications would also affect dreaming.

preparations reported to alter sleep and

This approach of studying REM sleep as

dreaming is diverse and extensive. Almost

and medications





Medications Altering Dreaming

all of the agents exerting neurochemical

reported to alter dreaming are widely used

effects on dopamine, nicotine, histamine,

across-the-counter preparations, includ¬

GABA, serotonin, and norepinephrine will

ing the sedating antihistamines commonly

alter sleep and dreaming for some patients

used to treat allergies and induce sleep,

(Pagel, 2006, pp. 225-240; Pagel & Heifer,

and nicotine-replacement agents utilized

2003, pp. 59-67).

in helping individuals to stop smoking.

Disordered dreaming and nightmares

Among prescription medications in clini¬

are also commonly reported during the

cal use, antihypertensive beta-blockers af¬

withdrawal from addictive medications

fecting norepinephrine neuroreceptors are

and drugs of abuse. This finding has been

the agents most likely to result in patient

postulated to be secondary to the occurrence

complaints of disturbed dreaming. The

of REM-sleep rebound during withdrawal

strongest clinical evidence for a drug to

from REM-sleep-suppressant medication.

induce disordered dreaming or nightmares

However, nightmares and disordered

is for the selective serotonin-reuptake in¬

dreaming are often reported as part of the

hibitor, paroxetine—a medication known

withdrawal syndrome from addictive med¬

to suppress REM sleep.

ications not known to affect REM sleep,

Based on its neurochemistry, dreaming

such as cannabis, cocaine, and opiates.

does not appear to be a simple or deriva¬

Disturbed dreaming and nightmares may

tive state of REM sleep. Medications that

be an intrinsic part of the process of with¬

induce effects and/or side effects of arousal

drawal from addictive agents (Pagel, 2006,

(insomnia) and/or sedation are those that

pp. 225-240). Some antibiotics, antivirals,

most commonly were reported to alter

and immunosuppressant drugs can induce

dreaming and nightmare frequency. Dream

complaints of sedation, insomnia, and

frequency and content is most likely to be

nightmares. A clear, but poorly defined,

altered by medications inducing the effects

relationship exists between host defense

and/or side effects of insomnia or daytime

and infectious disease, and sleep/dream¬

sleepiness and altering our alertness and

ing. Some of the agents reported to cause

cognitive interaction with the world.

altered dreaming are induction anesthet¬ ics utilized in surgery, agents that can also induce waking hallucinations and confu¬ sion. This association suggests that agents which alter an individual’s conscious re¬ lationship to the external environment can alter dream and nightmare occurrence. The fact that a wide spectrum of phar¬ macological agents is reported to affect dreaming suggests that the biochemical

James F. Pagel

References Hobson, J., Pace-Schott, E., & Stickgold, R. (2003). Dreaming and the brain: Toward a cognitive neuroscience of conscious states in sleep and dreaming. In E. Pace-Schott, M. Solms, M. Blagrove, & S. Hamad (Eds.), Sleep and dreaming: Scientific advances

(pp. 1-50). Cam¬ bridge: Cambridge University Press. and reconsiderations

less understood than is generally sug¬

Pagel, J. F. (2006). The neuropharmacology of nightmares. In S.R. Pandi-Perumal, D.P. Cardinali, & M. Lander (Eds.), Sleep and

gested. The medications most commonly

sleep disorders: Neuropsychopharmacologic

basis for dreaming is more complex and

Medieval Hagiography and Dreams


approach (pp. 225-240). Georgetown, TX:

as a multifaceted phenomenon involving

Landes Bioscience.

the body, the mind, and the senses.

Pagel, J.F., & Heifer, P. (2003). Drug induced nightmares—An etiology based review. Human Psychopharmacology: Clinical and Experimental, 18, 59-67.

In medieval saints’ lives {vitae; hagi¬ ography), dreams appear during crucial stages in which the saint gains clarity of his life and grows spiritually. The conver¬ sion of the saint to a life in the footsteps of Jesus Christ and according to the teachings

Medieval Hagiography and Dreams

of the Gospel is a gradual process from a narrow orientation on worldly things to an open attitude toward supernatural signs

The great theologian Thomas Aquinas

and admonitions. In this process, the saint

(1225-1274) described four causes of

is continuously led by images in the form

dreams: “two inward ones, arising from

of visions, dreams, apparitions, or revela¬

daytime preoccupations and from physical

tions; terms that are not well defined and

humors, and two outward ones, arising from

not strictly demarcated from each other in

physical sources (temperature or astrologi¬

medieval hagiography. As topology dic¬

cal forces) and from God or demons” (Van

tates, their meaning is not clear to him

de Castle, 1994, p. 81). Another late me¬

from the beginning and he fails to interpret

dieval theologian, Bonaventure (ca. 1221—

them correctly. But with the help of God

1274), discerned five causes of dreaming:

he gradually experiences the true meaning

a disposition of the body; an anxiety of

of the images that are revealed to him, and

the mind; diabolic illusion; angelic revela¬

learns to act on them effectively. He ac¬

tion; and divine visitation (Kruger, 1992,

quires the habit of true interpretation: they

p. 190). Many more classifications regard¬

are all crucial signposts on his way to God.

ing cause and nature of dreams can be

The dreams and visions therefore function

found in medieval thought, which inherited

as a means for spiritual progress.

important classical categories and schemes

But they are also a measure for it: dreams

of dreams and dreamlike experiences, or

and visions signal important spiritual stages

created new ones in the same epistemic

that the saint goes through. The saint’s biog¬

tradition (Dinzelbacher, 1981). In general,

rapher uses them as important elements of a

medieval dream theory shows the ambigu¬

literary program, employing the rhetoric of

ous quality of dreams and similar vision¬

hagiography. He writes a biography within a

ary phenomena: they are either important

biography: the course of events in the saint’s

or unimportant, either psychological or

earthly life parallels the development of his

spiritual, either legal or illegal, either ma¬

spiritual life. Obviously, all natural facts and

levolent or benevolent. Dreams can be an

events take place under a supernatural direc¬

illusion as much as they can be a revelation

tion. Dreams and visions are exemplary for

(Kruger, 1992, p. 74). Furthermore, they

this, as they reveal the presence of the su¬

are never described in sec psychological or

pernatural in everyday circumstances and,

physiological terms, but always presented

at the same time, place natural images in




Melatonin Therapy for the Sleep Disorders of Children

a supernatural context. The dreams of the

dreaming individual itself (Frugoni, 1989,

saint are a most effective instrument in the

p. 76). Both the reception of hagiographi¬

hands of the medieval hagiographer, who

cal dreams by the medieval public and its

wishes to demonstrate to his faithful public

effects on medieval spirituality therefore

the divine origin of the saint’s actions and

need much further investigation. Krijn Pansters

the imitable aspects of his holiness. Medieval hagiographical dreams can therefore be said to be symbolic in content

See also: entries related to History of Dreams/ Sleep

as well as in function. The dreams of the man or woman of God are never considered


to be a normal, daily, anthropological phe¬

Dinzelbacher, P. (1981). Vision und Vision-

nomenon. As the materials of the account

sliteratur im Mittelalter. [Vision and vision

of a spiritual journey, they are symbolic in content, marking the most important stages on the saint’s way to sanctity (Frugoni, 1989, p. 73). They initiate new stages or conclude previous ones, as can be seen in the gradual conversion process of such great saints as Francis of Assisi (Pansters, 2009). The saint’s dreams are furthermore symbolic in function. They are portrayed as stemming from God, who leads the saint on his spiritual path, whereas in fact the biographer guides the saint’s admirer, the story’s reader or listener, on his path. If the saint really had dreams revealing that the will of God must remain unclear, the function of the biographical account is not the narration of the saint’s holiness in itself. Vitae are concerned with the exemplary il¬

literature during the Middle Ages.] Monographien zur Geschichte des Mittelalters [Monographs on the history of the Middle Ages] 23. Stuttgart: Hiersemann.

Frugoni, C. (1989). DieTraume inder Legende der drei Gefahrten. [Dreams in the legend of the three companions.] In A. Paravicini Bagliani & G. Stabile (Eds.), Traume im Mit¬ telalter.

lkonologische Studien


in the Middle Ages: Iconological studies]

(pp. 73-90). Stuttgart: Belser. Kruger, S.F. (1992). Dreaming in the Middle Ages. Cambridge Studies in Medieval Lit¬ erature 14. Cambridge: Cambridge Univer¬ sity Press. Pansters, K. (2009). Dreams in medieval saints’ lives: Saint Francis of Assisi. Dreaming, 19, 55-63. Van de Castle, R.L. (1994). Our dreaming mind: A sweeping exploration of the role that dreams have played in politics, art, re¬

lustration and divine legitimization of the

ligion, and psychology, from ancient civi¬

holiness of the saint as well as with the re¬

lizations to the present day. New York:

ligious incitement to holiness of its admir¬

Ballantine Books.

ers. Both of these aims are reflected in the typical and topological nature of the me¬ dieval biographical account. The dreams described are exemplary and paraenetic

Melatonin Therapy for the Sleep Disorders of Children

in character: they report miracles in order to create them and virtues in order to in¬

Melatonin research in sleep medicine

duce them. They are more concerned with

has been very active during the last 20

the dream-reading collective than with the

years. Since there are a huge number of

Melatonin Therapy for the Sleep Disorders of Children


publications on this topic, the readers are

sleep for six to eight hours. They are more

referred only to a couple of articles writ¬

beneficial for individuals who have pro¬

ten by our team ( Carr et al., 2007; Jan &

longed awakenings during the night, with

O’Donnell, 1996; Jan et al., 2007; Wasdell

or without difficulty falling asleep.

et al., 2008).

Melatonin is remarkably free from side

Melatonin (N-acetyl-5-ethoxytryptamine)

effects, even with high doses. It is not ad¬

is secreted by the pineal gland, usually

dictive and tolerance does not develop

throughout the night because healthy sleep

after prolonged use. In numerous animal

habits and darkness promote its produc¬

studies, melatonin during pregnancy has

tion; however, unhealthy sleep habits and

not caused any abnormalities in fetuses.

light inhibit it. It is also produced in min¬

It is also safe when taken during puberty,

ute amounts by most tissues. Melatonin is

and in humans it does not appear to affect

a small lipid and water-soluble molecule

its onset. Melatonin therapy does not cause

that readily enters the bloodstream, the spi¬

seizures, as once was thought; in fact it has

nal fluid, all body compartments, and cells.

anticonvulsant properties. It can be taken

It has many important functions, such as

with most other medications and it even

sleep regulation, brain development, pro¬

appears to reduce their side effects. One of

tection against toxins; it has anticonvul¬

the observations of some people who are

sant and anticancer properties; and it is also

on melatonin therapy is that their dreams

beneficial in treating many diseases. This

are more vivid but it is rarely disturbing

molecule is the most powerful antioxidant

enough to prevent treatment. This curious

known and is also a synchronizer of meta¬

effect of melatonin has not been studied

bolic activities in the body.

and the neurophysiological reasons for it

For the purpose of sleep promotion, mel¬

are not understood. However, melatonin

atonin is synthesized commercially and is

is known to influence both NREM- and

sold as an over-the-counter medication in

REM-sleep stages, and during REM sleep

the United States and Canada. In contrast,

dreaming is the most intense. With pro¬

in Europe it is a prescription drug. Melato¬

longed melatonin treatment, dreams tend

nin has very different properties from regu¬

to become less vivid.

lar hypnotics and although it has hypnotic

Melatonin therapy is recommended by

properties, it is not considered to be a sleep¬

the American Association for Sleep Medi¬

ing pill. The fast-acting formulations, such

cine for circadian rhythm sleep disorders

as sublingual tablets, capsules, and liquid

(CRSD), which include persistent diffi¬

begin to promote sleep within 30 minutes

culty falling asleep, prolonged awakenings

after swallowing them, but their effects

during the night, regular early morning

only last for four to five hours. They are

awakenings, and jet lag. There are also

most useful for those individuals who have

other, less common forms of CRSD. These

difficulty falling asleep. Most slow or con¬

circadian sleep disorders are characterized

trolled release Tablets release some mela¬

by dissociations between sleep-wake be¬

tonin quickly and some slowly; therefore,

haviors and the environment and are asso¬

depending on their makeup they promote

ciated with abnormally timed or impaired




Methodological Challenges in the Scientific Study of Dreams

pineal melatonin production. This is why

It can be stopped abruptly without ill ef¬

melatonin-replacement therapy is so ben¬

fects. It is recommended that the treatment

eficial for CRSD. Since the brain is closely

should be stopped every 6 to 12 months to

involved in pineal

see whether it is still necessary.

melatonin produc¬

James E. Jan

tion, these sleep disorders are common in children with various neurodevelopmen-

See also: entries related to Sleep Disorders

tal disabilities, especially with intellectual deficits. A medical evaluation prior to mela¬ tonin therapy is beneficial, because this treatment is mainly effective for CRSD, and sleep difficulties could be caused by more than the 100 sleep disorders that are known to occur in children. Prior to treat¬ ment, attempts should be made to establish healthy sleep habits, since milder sleep dis¬ turbances may respond to these measures alone. The oral dose of melatonin should be taken about 30 minutes prior to the desired bedtime. Some physicians also prescribe a smaller dose a few hours before bedtime, but we do not find this practice useful. There is no dose formula to fit everyone, because the type and severity of sleep dif¬ ficulties markedly vary. Starting with one to three milligrams is best, with small in¬ creases every couple of days, until the lowest and most effective dose is reached. Delayed sleep onset can usually be treated with smaller doses, in contrast to sleep-

References Carr, R., Wasdell, M.B., Hamilton, D., Weiss, M.D., Freeman, R. D., Tai, J., . . . Jan, J.E. (2007). Long-term effectiveness out¬ come of melatonin therapy in children with treatment-resistant circadian rhythm sleep disorders. Journal of Pineal Research, 43, 351-359. Jan, J.E., & O’Donnell, M.E. (1966). Use of melatonin in the treatment of paediatric sleep disorders. Journal of Pineal Research, 21, 193-199. Jan, J.E., Wasdell, M.B., Reiter, R.J., Weiss, M. D., Johnson, K. P., Ivanenko, A., & Free¬ man, R. D. (2007). Melatonin therapy of pe¬ diatric sleep disorders: Recent advances, why it works, who are the candidates and how to treat. Current Pediatric Reviews, 3, 214-224. Wasdell, M. B., Jan, J. E., Bomben, M. M., Free¬ man, R. D., Rietveld, W. J., Tai, J.,... Weiss, M. D. (2008). A randomized, placebo-con¬ trolled trial of controlled release melatonin treatment of delayed sleep phase syndrome and impaired sleep maintenance in children with neurodevelopmental disabilities. Jour¬ nal of Pineal Research, 44, 54-64.

maintenance difficulties. From time to time, when a person is more alert, another dose of melatonin may be taken at bedtime, or a couple of hours later, but repeating the

Methodological Challenges in the Scientific Study of Dreams

dose toward the morning is rarely helpful. Once the therapeutic threshold has been

The interdisciplinary field of dream studies

reached, additional melatonin does not re¬

is rife with questions regarding how, what,

sult in deeper sleep. Depending on the type

and why we dream. How are dreams con¬

of sleep disturbance, the treatment may be

structed? Why are dreams often difficult

required for only a short time, or for years.

to remember? Are most dreams bizarre?

Methodological Challenges in the Scientific Study of Dreams


What are the predictors of dream recall?

this distinction is not uniformly agreed

What is the connection between waking

upon by dream investigators (Pagel, 2008).

experience and dreaming? Does dream¬

Minimally, in any study of dreaming, the

ing serve a developmental function? Does

abstract concepts of dream and dreaming

dreaming assist with information process¬

must be translated into operational defi¬

ing and memory formation? Can work¬

nitions that specify, in precise behavioral

ing with dreams bring about personal

terms, exactly how a dream or dreaming


will be measured.

Many methods are used to investigate

The second methodological challenge

dreaming, including phenomenology, eth¬

concerns how we study dreams and dream¬

nography, longitudinal case studies, and

ing; that is, how do we obtain evidence of

literary analysis. Each method has its own

dreaming? Questions associated with this

approach to the question of what consti¬

challenge include: What is the measure

tutes evidence for a truth claim. This entry

of dreaming? When and where are these

focuses on the use of scientific method in

measures obtained? Whose dreams are

dream studies. The application of the sci¬

sampled? We will consider each of these

entific method entails formulating test¬

questions in turn.

able hypotheses to assess the accuracy

What is the measure of dreaming? An

(validity) of theoretical claims and identi¬

intractable fact in dream studies is that any

fying the range of circumstances (bound¬

measure of dreaming is necessarily indi¬

ary conditions) under which these claims

rect: the dream as told is not the dream

hold true. Dream scientists face numer¬

as experienced. Verbal reports of dream¬

ous methodological challenges in these ef¬

ing are the typical index of dreaming. The

forts including how to maximize a study’s

reliance on verbal reports poses several

construct validity (e.g., how are dreams

challenges to the accuracy of claims made

defined, measured, sampled?), internal

about the features of dreams and about the

validity (e.g., are we studying dreaming

dream-generation process. Because the

as a type of subjective experience or as

narrative report is a verbal representation

an instance of autobiographical recall?),

of a multimodal experience that may be

and external validity (e.g., to whom do our

more or less difficult to describe in words,

findings apply?).

the report is typically guided by a narra¬

The first methodological challenge con¬

tive schema that emphasizes the dream

cerns the question of what we are studying.

story (who/what/when/where) over quali¬

Definitions of dreams vary from a detailed

tative aspects such as the perceptual, cog¬

narrative account of experiences recalled

nitive, or affective features of the dream

upon awakening from sleep to any experi¬

experience (Kahan, 1994). In short, certain

ence specific to the sleep state. Often, dream

features of subjective experience are more

is used to refer to the verbal report of an ex¬

likely than others to be included in the ver¬

perience occurring in sleep and dreaming

bal report.

is used to refer to the processes involved

Other measures of dream recall inclu¬

in generating the experience—but even

de questionnaire measures, diary reports,




Methodological Challenges in the Scientific Study of Dreams

Internet-based surveys, and the use of tar¬


(under what conditions) are

geted probes to assess specific qualities of

measures of dreaming obtained? Dream

the dream experience. The recall of dreams

researchers disagree on whether dream

is sometimes compared with the recall of

experiences are best sampled in the home

waking experiences. Investigators disagree

setting or in the sleep laboratory. Labo¬

as to the best choice of waking-state com¬

ratory awakenings allow investigators to

parison: some argue that reports of dream¬

control the conditions under which dream

ing experience should be compared with

reports are obtained. They also minimize

reports of waking experience; others argue

the influence of memory factors such as the

for comparing the qualities of dreams with

salience or emotional intensity of the expe¬

the qualities of waking fantasy. The choice

rience on dream recall. Sampling dreams

of waking-state comparison is, in impor¬

from laboratory awakenings allows re¬

tant ways, influenced by one’s theoretical

searchers to test hypotheses concerning

perspective on the relationship between

the relationship between the qualities of

dreaming and waking. Investigators should

reported dreams and factors such as sleep

take steps to minimize the demand charac¬

stage, time of night, and method of awak¬

teristics in their studies and strive to ob¬

ening. On the other hand, laboratory-based

tain samples of dreaming and waking that

studies are expensive and time consuming

are as comparable as possible (Kahan &

for both participants and investigators.

LaBerge, 2011).

Some researchers have argued that dreams

When are measures of dreaming ob¬

sampled in the sleep lab are less vivid and

tained? A study of dreaming is, essen¬

detailed than those sampled in the home

tially, a study of autobiographical memory


(Horton & Conway, 2009). As the delay

studies comparing lab- and home-based

between a dream experience and the re¬

dream recall have found few reliable dif¬

port of that experience increases, the more

ferences (Strauch & Meier, 1996). Recent

the verbal report reflects autobiographical

technological developments in home-sleep

memory and its attendant constructive and

recording systems offer a hybrid approach

reconstructive processing. For example,

to those investigators interested in acquir¬

one recalls less of their dream experience

ing both sleep and dreaming data in the

when a demanding cognitive task inter¬

more naturalistic, home environment.




venes between the dream experience and

Whose dreams are investigated? The

the dream report (Parke & Horton, 2009).

frequency, characteristics, and content of

A researcher’s concern with memory in¬

dreams are related to numerous individual

fluences on dream reporting will vary with

difference factors. These include gender,

the research question. Dream researchers

cognitive style, memory abilities, attention

who are interested in the cognitive or af¬

skills, attitude toward dreams, and cultural

fective processes involved in dream gen¬

or religious orientation, to name but a few.

eration should be especially attentive to the

Ultimately, the questions about dreams/

influence of memory processes, as well as

dreaming that can be investigated scientif¬

to the potential limits of verbal report data.

ically depend on the participants’ level of

Middle Ages and Dreams


dream recall, verbal expertise, and skill in

science, cognitive neuroscience, cognitive

self-observation. For example, investiga¬

psychology, anthropology, and sociology.

tors interested in comparing the qualities

Tracey Lea Kahan and

of dreaming versus waking experience are

Caroline L. Horton

concerned with obtaining reports of sub¬ jective experience that are as accurate as possible. In this regard, participants need excellent source-monitoring skills, nota¬ bly, the ability to distinguish between the characteristics of what they experienced prior to awakening (e.g., the dream expe¬ rience) and what they are inclined to add to the experience in the course of recall

References Horton, C.L., & Conway, M. A. (2009). The memory experiences and dreams question¬ naire: A validated measure of dream re¬ membering. Imagination, Cognition and Personality, 29(1), 3-29. Kahan, T.L. (1994). Measuring dream self¬ reflectiveness: A comparison of two ap¬ proaches. Dreaming, 4(3), 329-344.

may be needed to study particular quali¬

Kahan, T.L., & LaBerge, S. (2011). Dream¬ ing and waking: Similarities and differences revisited. Consciousness & Cognition, 20, 494-519.

ties of dreams, such as perceptual detail,

Pagel, J.F. (2008). The limits of dream: A sci¬

(e.g., commentary on connection to wak¬ ing life). A high level of dream recall also

bizarreness, emotion, cognitions, or self-

entific exploration of the mind/brain inter¬

reflective processes.

face. New York: Academic Press.

Individual differ¬

ence factors which may be correlated with dream recall, dream reporting, or dream qualities may be controlled or their influ¬ ence measured. Of course, the generalizability of the study’s findings must be

Parke, A.R., & Horton, C.L. (2009). A re-ex¬ amination of the interference hypothesis of dream recall and salience. The International Journal of Dream Research, 2(2), 60-69. Strauch, I., & Meier, B. (1996). In search of dreams: Results of experimental dream re¬

qualified accordingly. Finally, in view

search. Albany: State University of New

of the wide variation in dream recall and

York Press.

skill in dream reporting, dream researchers should be careful to include sample sizes large enough to detect small, yet meaning¬ ful, differences.

Middle Ages and Dreams

Researchers who endeavor to apply the scientific method to the study of dreams

During the Middle Ages, discussions of

and dreaming are encouraged to wrestle—

dreams and dream interpretation appeared

creatively, publicly, and persistently—with

in poetry, philosophy, theology, autobiog¬

the substantial methodological challenges

raphy, religious writings, and in other areas

inherent in dream science. Such efforts en¬

of thought. For example, three popular

hance the quality of the empirical evidence

types of interpretive manuals survive: the

obtained and the accuracy of claims made

dream alphabet, the dream lunar, and the

concerning what, how, and why we dream.

dream book proper, otherwise known as

Finally, these efforts help extend the reach

the Somniale Danielis, which was a key to

of dream research to the fields of sleep

dream imagery supposedly written by the




Middle Ages and Dreams

prophet Daniel. All these interpretive sys¬

of oneirocriticism entered medieval culture

tems share the feature of not leaving much

through numerous Arabic translations and

room for either God’s or human will, ac¬

commentaries, whose influence permeated

cording to Steven Kruger, who writes that,

medical works in England and the conti¬

additionally, for more sophisticated medi¬

nent. Physicians used these texts as keys

eval authors, there was “a remarkable unity

to reliable diagnoses of patients’ illnesses

of opinion about the essential, fundamen¬

and built on their assertions, such as those

tally complex and ambiguous, nature of the

about the center of sense perception and

dream” (Kruger, 1992, p. 6). This entry will

the causes of sleep, with new discoveries.

focus on the impact of dreaming on three

Macrobius divides dreams into five

fields: philosophy, religion, and literature.

kinds, three of which are true or revela¬

In addition to the influential Aristotle

tory (oraculum, visio, and somnium) and

(.Parva Naturalia: De Somno et Vigilia,

two of which are false (insomnium and

De Insomniis [Little Nature: On the Sleep

visum). In doing so, he successfully brings

of Vigilance, on Insomnia] and De Divi-

together various ancient theories, from the

natione per Somnum [On Divination in

notion that dreams can be divine to the idea

Sleep]), on the one hand, and Augustine

that they are negligible because they result

(Confessions), on the other, Macrobius

from bad digestion. The genre of the som¬

(Commentary on the Dream of Scipio)

nium, or enigmatic dream, is the category

and Calcidius (Commentary on Plato’s 77-

of dream experience that is probably clos¬

maeus), two late antique writers, are im¬

est to the literary dream. The enigmatic

portant to medieval theories of dreaming

dream has five types (personal, alien, so¬

with their hierarchy of types of dreams,

cial, public, and universal), and it “stands

from the mundane to the visionary. Artemi-

between, and in some sense unites, the op¬

dorus’s Oneirocritica also is referred to in

posed realms of truth and falsehood” (Kru¬

the Middle Ages, particularly in Arabic-

ger, 1992, p. 23). For Macrobius, Cicero’s

language texts. His most influential idea is

“Dream of Scipio,” which appears at the

that the dream interpreter must know about

end of De Re Publica, contains elements

the personality, career, age, and other in¬

of the first three types, and he brings to

formation about the dreamer. For Aristotle,

bear wider topics such as mathematics,

dreams are merely physical, though he, like

astronomy, morality, geography, and reli¬

Artemidorus, admits that: “the most skilled

gion. He is the most influential of the alle-

interpreter of dreams is one who can

gorists who, as Patricia Cox Miller claims,

observe resemblances” (Aristotle, 1996,

“operated out of an expectation of textual

p. 115); he is also sympathetic to the idea

polysemy and so delighted in the conver¬

of prophecy, but not to a large degree. Ar¬

gence of infinite relationships that onei¬

istotle, who focused on physical ailments

ric images set in motion” (Miller, 1998,

that dreams can signal, was by far the most

p. 97). Interpreting a dream was like in¬

popular writer on dreams. Like the medi¬

terpreting a poem in full detail, with each

cal writings on dreams by Hippocrates and

image and action worthy of paragraphs of explication.

Galen, Aristotle’s naturalistic philosophy

Middle Ages and Dreams


Augustine’s ideas about dreams appear

for one’s sins, one’s interiority needs to be

in Confessions and De Continentia (On

disciplined, and that virtue is defined as the

Continence), where he holds that dreams

struggle to achieve this control.

can be compelling as well as prophetic, but

Religious writers during the Middle

also that at times another force takes over

Ages were preoccupied with dreams in

one’s body and creates the conditions in

Islamic, Jewish, and Christian contexts.

which sexual excitement is possible and

Medieval Islamic writers, including some

is not considered sinful. The Confessions

Sufis, were influenced by Artemidorus’s

contain an observation about the reliabil¬

Oneirocritica (second century AD), by Ar¬

ity of dreams: “Food pictured in dreams is

istotle, and by the Bible.1 They tended to

extremely like food received in the waking

concentrate on the role of the imagination

state; yet sleepers receive no nourishment,

in creating dreams; al-Ghazali (d. 1111)

they are simply sleeping. But those fanta¬

and Ibn al-’Arabi (d. 1240) are examples of

sies had not the least resemblance to you as

authors with such a preoccupation. Other

you have now told me, because they were

influential Muslim philosophers who dis¬

physical images, fictional bodily shapes....

cussed dreams are al-Farabi (d. 950) and

And yet again the pictures of these realities

Ibn Sina (d. 1037). “It was universally ac¬

which our imagination forms are more reli¬

cepted that those who had cultivated their

able than the mythological pictures of vast

inner faculties and insights could decipher

and unlimited entities” (Augustine, 1991,

the encoded messages of their own dreams

p. 41). His interest in prophetic dreams

as well as those of others” (Sviri, 1999,

is demonstrated through an account of

p. 252). Sufis recorded their dreams as well

a dream of his mother, in which she was

as those of others.

encouraged to allow him to live with her,

In medieval Judaism, Isaac Israeli (10th

and to sit at the same table in the house to¬

century) wrote that dream imagery for com¬

gether. She cries, and when a young man

mon people and in prophets’ revelations

asks why, she says she mourns her son’s

make “dreams a part of prophecy” (Sviri,

perdition (he has taken up with the wrong

1999, p. 255). Moses ibn Ezra, a poet,

crowd). He tells her not to worry and then

wrote that dreams derive either from within

she sees Augustine on same rule as this

or from celestial sources, and the latter are

young man: “By the dream the joy of this

the only veridical ones. One minor type of

devout woman, to be fulfilled much later,

dreaming was the astral dream, considered

was predicted many years in advance to

“the intersection between the astral order

give consolation at this time in her anxi¬

and private life, a moment of insight, ei¬

ety” (Augustine, 1991, p. 49). In De Con¬

ther a gift from above or a result of human

tinentia, Augustine addresses the issue of

initiative, enabling a person to peer into the

sexual continence; he had already done so

future by means of a mantic relationship

in the famous Chapter 10 of the Confes¬

to the celestial forces that shape that fu¬

sions, where the wet dream is a problematic

ture” (Idel, 1999, p. 236). More common

source of bodily knowledge for him. Au¬

were Kabbalistic dreams that were “a lin¬

gustine shows that when one is responsible

guistic kind of magic directed at angels”




Middle Ages and Dreams

(Idel, 1999, p. 238), although instructions

they faced an uphill battle because of the

exist for being the recipient of a dream

increasing popularity of dream books and

after standing under the stars. In the 12th

other popular interpretive traditions.

century, Abraham ibn Ezra wrote on Dan¬


literature contains


iel, both that naturalistic causes for dreams

famous instances of dreaming, from the

exist and that dreams could also be inter¬

framing of the poems Pearl and Piers

preted based on what hour a dream oc¬

Plowman to the work of Chaucer, who in¬

curred and the stars’ configuration at that

cludes dreams in several ways in his work.

time. His perspective on astral dreams ap¬

The Nun’s Priest’s Tale in The Canter¬

pears in the following century in an anon¬

bury Tales contains the story of a dream

ymous treatise. Maimonides was against

and its interpretation by the husband of

this practice, but a letter is attributed to him

the dreamer (both characters are birds),

that condones it and also uses a method of

and his narrative poems “The Book of the

purification, special language including

Duchess,” “The House of Fame,” and “The

anagrams, and the appearance within the

Parliament of Fowls” all contain dream

dream of Mercury (Hermes) to foster the

frames. A. C. Spearing, the most prolific of

dreamer’s “magical powers” (Idel, 1999,

a group of contemporary scholars of medi¬

p. 244) and greater understanding of the

eval dreaming, writes that “What especially

Torah. A treatise spuriously attributed to

interested Chaucer about the dream poem

ibn Ezra also contains an “astral-magic vi¬

as a genre, I suggest, were two things—on

sion of drawing down the emanation from

the one hand, the dream as one of the most

above by ritual means” (Idel, 1999, p. 246).

intriguing kinds of natural experience we

Christian authors were alternately fasci¬

have, and, on the other, the possibility of

nated by and hesitant about dreams. Many

constructing poems that reproduce certain

mystical writings, such as those by Julian

aspects of that experience as literary form”

of Norwich, Gertrude of Helfta, Guibert

(Spearing, 2010, p. 167). The aspects of

de Nogent, Hermann of Cologne, and The

dreaming that Chaucer seemed most eager

Book of Margery Kempe display an af¬

to represent include careful attention on the

finity for visions and often dedicate their

part of dreamers and interpreters alike to

lives to religious pursuits in accordance

details of language and dialogue, descrip¬

with their dictates. On an institutional

tions of landscapes that place the dreamer

level, however, dreams indicate “the basic

in realistic but also imaginative surround¬

limits of ecclesiastical power, showing it

ings, and a general tone of nostalgia as the

incapable of controlling all the arcane of

dream is recalled. Literary writers, philos¬

individual religious experience, even if

ophers, and religious writers alike found in

clerics assumed the essential role of sav¬

dreams intensely provocative and intensely

ing the dream narratives from oblivion by

illuminating material with which to ponder

recording, classifying, and judging them”

the epistemological status of mental activ¬

(Schmitt, 1998, p. 275). As much as au¬ thorities in the church wanted to limit indi¬

ity when it occurs in the absence of waking life’s stimuli.

vidual believers’ engagement with dreams,

Jenn Lewin

Mugwort: A Dream-Stimulating Herb


(Doctoral dissertation, University).


1. A new English translation of Artemidorus’s Oneirocritica will appear in October 2012, with slightly revised Greek text and extensive introduction and commentary, written by Dan¬ iel E. Harris-McCoy, Artemidorus’ Oneirocrit¬ ica: Text, Translation, and Commentary (New York: Oxford University Press, 2012).



Phillips, H., & Havely, N. (Eds.). (1997). Chau¬ cer’s dream poetry. London: Longman. Russell, J.S. (1988). The English dreamvision: Anatomy of a form. Columbus: Ohio State University Press. Schmitt, J.-C. (1998). Ghosts in the Middle Ages: The living and the dead in Medieval society (Trans. Teresa Lavender Fagan).


Chicago: University of Chicago Press.


(1996). Aristotle on sleep and dreams: A text and translation (Trans. David Gallup). Warminster, UK: Aris & Philips.

Augustine. (1991). Confessions (Trans. Henry Chadwick). Oxford: Oxford University Press. Barr, J. (2010). Willing to know God: Dream¬ ers and visionaries in the later Middle Ages.

Columbus: Ohio State University Press. Edwards, R. (1991). The dream of Chaucer: Representation and reflection in the early narratives. Durham, NC: Duke University

Press. Idel, M. (1999). Astral dreams in Judaism: Twelfth to fourteenth centuries. In D.D. Shulman & G. G. Stroumsa (Eds.), Dream cultures: Explorations in the comparative

Shulman, D., & Strousma, G.G. (1999). Dream cultures: Explorations in the comparative history of dreaming. Oxford: Oxford Uni¬

versity Press. Spearing, A.C. (2010). Dream poems. In S. G Fein & R. Raybin (Eds.), Chaucer: Con¬ temporary approaches (pp. 159-178). Uni¬ versity Park: Pennsylvania State University Press. Sviri, S. (1999). Dreaming analyzed and re¬ corded: Dreams in the world of medieval Islam. In D. D. Shulman & G. G. Stroumsa (Eds.), Dream cultures: Explorations in the comparative history of dreaming (pp. 252273). New York: Oxford University Press. Windeatt, B. A. (Ed.). (1982). Chaucer’s dream poetry: Sources and analogues. Cambridge: D. S. Brewer.

history of dreaming (pp. 235-251). New

York: Oxford University Press. Kruger, S.F. (1992). Dreaming in the Middle Ages. Cambridge: Cambridge University Press.

Mugwort: A DreamStimulating Herb

Lynch, K.L. (1988). The high medieval dream and literary

Oneirogens are plants or other substances

form. Stanford, CA: Stanford University

that enhance dreaming (Toro & Thomas,


2007). One of the most widely used plants

vision: Poetry, philosophy,

Lynch, K. L. (Ed.). (2007). Geoffrey Chaucer, dream visions and other poems. New York: W.W. Norton. Miller, P.C. (1998). Dreams in late antiquity: Studies in imagination of a culture. Prince¬ ton, NJ: Princeton University Press.

associated with stimulating vivid dreams is mugwort. Its common name originates from its extensive use in brewing beer prior to the introduction of hops. Wort is an old English term for herb as many Harry Potter

Newman, F.X. (1963). Somnium: Medieval

fans have learned. Mugwort’s genus name

theories of dreaming and the form of vision

is Artemisia, which is linked to the Greek




Mugwort: A Dream-Stimulating Herb

goddess Artemis, who was associated with

The dream-inducing properties of mug¬

healing women’s diseases and helping

wort are generally accessed by making a

with childbirth along with connections to

dream pillow with dried mugwort leaves,

wilderness, wild animals, and hunting (Sil¬

often mixed with other herbs such as lav¬

verman, 1997). The strong fragrance, the

ender, which is reported to be soothing.

variations in the leaf shape and the unique

Pillows with mugwort can be purchased

two colored leaves with silvery fibers on

or made using cotton or other soft fabrics.

the bottom are probably what drew people

Users who enjoy crafts may want to design

to explore the uses of the plant in ancient

and decorate their own dream pillow with


inspiring symbols or with images from

Mugwort is in the aster family (.Astera-

their own dreams. Fresh leaves on your

ceae), which has also been known as the

pillow are the easiest way to experiment.

daisy or sunflower family. The genus Ar¬

A tea is another way to try out the onei-

temisia is commonly found in North and

rogenic effects of mugwort. However, the

South America, Europe, Africa, and Asia

taste is bitter and those who want to ingest

(see the Viable Herbal Solutions website

the herb may prefer to purchase or make a

at http://www.viable-herbal.com/singles/

capsule with dried or powdered mugwort.

herbs/sl38.htm). One species of mug¬

The study of ethnobotany focuses on hu¬

wort, Artemisia vulgaris, is so common

mans relationships with plants (Veilleux &

in the eastern United States and Europe

King, n.d.). Agriculture- and plant-based

that it often appears as a weed (Artemisia

medicines developed as a result of cen¬

vulgaris, n.d.). Very similar in appear¬

turies of trial-and-error experimentation.

ance and usage is Artemisia douglasiana,

Many crucial advances in medicine have

which is common on the West Coast of the

come from plants and one of the many ra¬

United States in forests and undisturbed

tionales for preserving the earth’s rain

areas (Hickman, 1993). Mugwort is a

forests is the likelihood that crucial medic¬

highly aromatic plant that varies in height

inal and nutritional plants exist there that

from one to five feet tall with divided or

have yet to be studied or even discovered.

lobed leaves that are a darker olive green

Botanists have identified the chemical

on top and more of a silvery green color

properties of oneirogenic herbs that may

with white downy hairs on the bottom.

eventually be linked to influencing dreams

The leaves are polymorphic, meaning that

or other medicinal benefits. Along with

individual leaf shapes may vary with most

other avenues of dream research, learning

leaves having three to five lobes or divi¬

more about these plants may contribute to

sions that are mitten like (Foster & Hobbs,

understanding the nature of dreaming and

2002). It is easy to cultivate and can be¬

its use in healing and awareness.

come naturalized in a garden. It can be

Popular interest in dreams, natural heal¬

used fresh or dried and the procedures for

ing, and cross-cultural spiritual and me¬

gathering, drying, and storing mugwort

dicinal practices burgeoned in the late 20th

are similar to those used for other herbs,

century. This led to increased interest in

spices, and botanicals.

oneirogens such as mugwort to enhance

Mugwort: A Dream-Stimulating Herb


dream recall, stimulate vivid dreams, and

habitats or damage other plants that may

to cultivate lucid dreams that occur when

be less common.

the dreamer is aware they are dreaming.

While research on the oneirogenic plants

Despite increased interest and abundant

may proceed slowly, we know that there

anecdotal reports, research on the pos¬

are a number of potential therapeutic ben¬

sible benefits of oneirogenic plants and

efits common to all medicinal treatments.

other substances is proceeding slowly due

The first is the placebo effect that has a

to lack of funding. Most of the reported

powerful therapeutic impact and can en¬

oneirogenic benefits of mugwort and other

hance traditional and alternative medicine.

herbs and substances have not been scien¬

The patient’s expectation of healing can in¬

tifically confirmed. Therefore, it is impor¬

fluence the success of any treatment with

tant to keep in mind that the information in

traditional or alternative medicine. Also,

this article should be taken as educational

the relationship with the physician, psy¬

only and not as a medical recommendation

chotherapist, healer, or shaman can have a

or a substitute for any necessary treatments

positive influence. In addition, using onei-

that are evidence based or approved by the

rogens or other medical therapies in the

FDA or other governmental entities. In ad¬

context of strongly held cultural religious

dition, two important cautions to be con¬

beliefs and ritual may have an impact that

sidered are that some people are allergic

is synergistic, by combining the placebo

to the pollen from mugwort flowers, and

effect, positive expectations, and culturally

that any wild plant should be definitively

sanctioned results along with potential me¬

identified before using it to prevent inad¬

dicinal or psychoactive influences of mug¬

vertent exposure to a harmful plant such

wort or other oneirogens being used.

as poison oak or ivy, hemlock, or stinging

Plant-based oneirogens have been used

nettles. In addition, thujone, a compound

in two general ways. They are taken before

found in varying degrees in mugwort, can

sleep in various forms to stimulate dream¬

have neurotoxic and mutagenic side effects

ing and they are used to induce a dream¬

when used in excess, and pregnant women

like state that closely parallels the sensory

should avoid or use medical advice before

and mental experience of a vivid dream.

ingesting mugwort preparations (Artemisia

Some of the best known plant oneirogens

vulgaris, n.d.). In general, if a tea or extract

combine both effects. A good example of

is used, it is best to use water rather than

an herbal oneirogen used to induce both

oil to extract the medicinal effects because

dreamlike states and powerful dreams is

the resulting tea or tincture will be milder

ayahuasca (Banisteriopsis caapi), which

when steeped in water (Foster & Hobbs,

is used by tribes in the Amazon rainfor¬

2002). In addition, some people are aller¬

est region and is referred to as vine of the

gic to the pollen from mugwort flowers.

soul in the Quechua language. In addi¬

Cooking may reduce or eliminate the risk

tion to many medicinal properties, it has

to those who are allergic. Finally, consider

hallucinogenic effects and is used in reli¬

growing your own mugwort and if you do

gious rituals by many tribes and sometimes

harvest the plant be careful not to disturb

combined with other herbs. The Achuar of




Mugwort: A Dream-Stimulating Herb

Peru use ayahuasca to stimulate dream¬

Mugwort has been revered over the centu¬

ing as an integral part of shaman-guided

ries for its magical, mystical, and spiritual

dream healing rituals that are central to

uses especially for warding off evil spirits

the cultural and spiritual practices of the

or enemies and for clairvoyance and pro¬

tribe (Parry, 2008). Researchers (Arehart-

moting romantic success. A 3,600-year-

Treichel, 2011) and journalists (Isaacson,

old Egyptian papyrus described the plant

2010) have reported profound dreams fol¬

in detail (see the Viable Herbal Solutions

lowing the ayahuasca ceremonies as well

website at http://www.viable-herbal.com/

as intense dreamlike experiences during

singles/herbs/s 138.htm). In art, Venus, the

the rituals. Another well-known mind-

Roman goddess of love, is sometimes de¬

altering oneirogen is Ubulawu, also known

picted holding a spray of mugwort in her

as African Dream Root (Silene capensis).

hand (Artemisia vulgaris, n.d.). In the first

The root is used by shamans in southern

century AD, the Roman writer Pliny the

Africa. Its root contains triterpenoid sapo-

Elder extolled the virtues of mugwort for

nins, which in even small doses are said

combating fatigue and stated that, “The

to induce remarkably prophetic vivid and

wayfaring man that hath the herb tied about

very colorful dreams that often allow tribe

him feeleth no weariness at all and he can

member to contact their ancestors (Toro &

never be hurt by any poisonous medicine,

Thomas, 2007).

by any wild beast, neither yet by the sun

Examples of oneirogenic plants that do

itself” (Silverman, 1997).

not radically affect waking consciousness

Mugwort is one of the nine magical herbs

but significantly alter dreaming include

of the Druidic and Anglo-Saxon tribes and

Dream Herb or Bitter Grass the Leaf of

was associated with protection of travelers

God (Calea ternifolia), which is used by

and fertility rites (Artemisia vulgaris, n.d.).

the Chontal people of Oaxaca, Mexico, for

In the Middle Ages, mugwort was worn in

oneiromancy or predicting future events

mid-summer on St. John’s Eve to gain se¬

or receiving divine guidance in a dream

curity against threats of evil possession.

(Toro & Thomas, 2007). Scientific stud¬

Medieval legends held that a dream pillow

ies have confirmed that the plant increases

of mugwort would allow people to see their

dream recall (Olin & Schneider, 2001).

entire future in their dreams (Callegari &

Another oneirogen, Red Spider Lily, has

Durand, 1977). Native Americans rubbed

an alkaloid, galantamine, which report¬

the leaves on their body to prevent dream¬

edly enhances the experience of dreaming

ing of the dead and to ward off ghosts, and

(Yuschak, 2006). Although its oneirogenic

they smoked, drank, and burned the herb

effects have not yet been scientifically con¬

for ritual purification (Foster & Hobbs,

firmed, a synthetic extract of galantamine

2002). In the 21st century, mugwort is used

has shown success in treating symptoms

for inducing lucid dreams and for stimulat¬ ing vivid dreams.

of Alzheimer’s disease (Olin & Schneider,


Most of the known oneirogen plants have

The origins of human fascination with

other reported medicinal uses, often in¬

mugwort stretch back across millennia.

volving mental functioning or the nervous

Mugwort: A Dream-Stimulating Herb


system. Mugwort has been utilized for cen¬

in aiding digestion. Wormwood has been

turies in conjunction with acupuncture. The

used for centuries to treat intestinal worms,

white downy fuzz on the underside of mug-

hence the common name for the plant. As

wort’ s leaves is removed and fashioned into

early as the 10th century, medicinal trea¬

cubes that are burned as moxa by acupunc¬

tises touted Artemisia's use in repelling

turists The smoking moxa cubes are placed

worms and other pests. In addition to its

over specific energetic meridians either di¬

ancient use for brewing, it is still used for

rectly or indirectly to amplify the effects of

flavoring beer, especially in Great Brit¬

the treatment. Called moxibustion, this an¬

ain, and some microbreweries are bring¬

cient treatment is still widely used in Chi¬

ing back mugwort beers. Finally, mugwort

nese medicine in the 21st century and has

seeds have been used for baking and for

shown promise with difficulties in labor in

flavoring in many foods. It is used in Korea

conjunction with acupuncture (.Artemisia

as a common ingredient in rice cakes, teas,

vulgaris, n.d.).

soups, and pancakes, and mugwort rice

Mugwort has traditionally been used in

cakes, or kusa mochi, are used for Japa¬

herbal medicine for soothing anxiety and

nese sweets called Daifuku (which means

for calming people who have suffered a

great luck) (.Artemisia vulgaris, n.d.).

seizure or drug overdose. Wormwood is

In addition to whatever medicinal, psy¬

in the same genus (Artemisia) and closely

chological, or spiritual benefits that plant

related to mugwort. It was used to prepare

oneirogens, such as mugwort, may prove

Absinthe, a powerful alcoholic drink with

to have, they are an enjoyable way to focus

psychoactive properties. It was popular in

on remembering and exploring dreams,

the late 1880s and early 1900s with art¬

can lead to a more active connection with

ists and writers, such as Baudelaire, Edgar

dreams, and increase interest in cross-

Allan Poe, and Van Gogh. In that era, it was

cultural dream healing practices. In addi¬

linked to brain damage and banned prob¬

tion, learning about plant oneirogens make

ably due to toxic copper salts used to brew

us more sensitive and aware of our con¬

it. Absinthe has become popular again in

nection with nature and promotes interest

the 21st century with nontoxic brewing

in ethnobotany. Finally, the exploration of

procedures (.Artemisia vulgaris, n.d.).

plant oneirogens and medicinal and nutri¬

Mugwort has many other reported me¬

tional uses of wild plants heightens pub¬

dicinal uses not related to mental func¬

lic awareness about the preservation of

tioning, including beneficial effects for

native plant species, which could help to

menstrual difficulties and labor pains, and

slow the accelerating decimation of plant

for treating fungal and bacterial infections.

communities that may be crucial to human

It is beneficial as an insect repellent and

survival. Alan Siegel

helpful against moths and other insects that invade gardens. It is considered a topical


treatment when a person is exposed to poi¬

Arehart-Treichel, J. (2011, March 4). Amazon people’s dreams hold lessons for psycho¬ therapy. Psychiatric News, 46(5), 9.

son oak or poison ivy. Mugwort is consid¬ ered to be a bitter herb that is beneficial




Music and Dreams

Artemisia vulgaris, (n.d.). Wikipedia. Re¬ trieved from http://en.wikipedia.org/wiki/ Artemisia_vulgaris. Callegari, J., & Durand, K. (1977). Wild edible and medicinal plants of California. El Cer¬ rito: Callegari and Durand. Foster, S., & Hobbs, C. (2002). Western medic¬ inal plants and herbs. New York: Houghton Mifflin. Hanrahan, C. (2011). Mugwort. Encyclope¬ dia of alternative medicine. Retrieved from http://findarticles.eom/p/articles/mi_g2603/ is_0005/ai_2603000533/ Hickman, J. (1993). The Jepson manual: Higher plants of California. Berkeley: Uni¬ versity of California Press. Hurd, R. (2009). Enhance your dreamlife. Phil¬ adelphia: dreamstudies.org.

Music and Dreams Anecdotal reports of music occurring in dreams can be found in a variety of places ranging from concert halls to Internet chat rooms to the field notes of anthropologists. While it is likely easiest to find high oc¬ currences of musical dreams among mu¬ sicians and among shamans, anyone can dream of music. Popular interest in the topic is evidenced by the many questions related to dreaming of music that have been posted on the interactive website Yahoo! Answers (http://answers.yahoo.com). Vis¬ itors to the site can provide responses from their own experience to questions such as

Isaacson, A. (2010, October 13). Amazon awakening. New York Times.

“What does it mean when you dream about

Olin, J., & Schneider, L. (2001). Galantamine for Alzheimer’s disease (Cochrane Review). Adult and Geriatric Treatment and Preventative Interventions Branch, National Institute of Mental Health (Co¬ chrane Database Syst Rev 2001 ;4: CD 001747).

you’ve never heard before?” and “Strange

Parry, B. (2008, June 10). Peruvian jungle. Retrieved from the BBC website: http:// www.bbc.co.uk/amazon/sites/peruvianjun gle/pages/content.shtml

dream song is often a confirmation of the

Silverman, M. (1997). A city herbal: Lore, leg¬ end and use of weeds. Woodstock, NY: Ashtree Press.

music?” “Is it possible to dream of music music in dreams?” Down through history, in indigenous cultures where shamanism is practiced, it is common for practitioners to be given sacred songs in dreams. Receiving such a shaman’s calling, and these songs are used in healing rituals and as a way to connect with the spirit world. One major study of these practices is documented in the book Healing Sounds from the Malaysian Rain¬

Toro, G., & Thomas, B. (2007). Drugs of the dreaming: Oneirogens: Salvia divinorum and other dream-enhancing plants. Roch¬ ester, VT: Park Street Press.

forest by musicologist and anthropologist

Veilleux, C., & King, S. (n.d.). An introduction to ethnobotany (Ed. L. Morganstein). Re¬ trieved from http://www.accessexcellence. org/RC/Ethnobotany/page2.php

dreams. Her collection includes 50 such

Yuschak, T. (2006). Advanced lucid dreaming: The power of supplements. Lexington, KY: Lulu Press.

was received (Roseman, 1993, p. 58).

Marina Roseman (1993). Roseman spent two years living with the Temiar, collect¬ ing stories about the songs that came from stories which detail the events of the day leading up to the dream in which the song Although a large-scale study of how common musical dreams are in the general

Music and Dreams


population has yet to be undertaken, a 30-

Billy Joel, Shawn Colvin, Rodney Crow¬

day study by Valeria Uga et al. (2006) spe¬

ell, Bruce Cockburn, Rory Block, David

cifically designed to collect musical dreams

Bowie, Brooks Williams, jazz musicians

found music occurring in approximately 20

Patti Cathcart and Chick Corea, and the

percent of nonmusicians’ dreams (n = 30)

South African a cappella group Ladysmith

and in approximately 40 percent of mu¬

Black Mambazo (Barrett, 2001; Grace,

sicians’ dreams (n = 35). Among other

2001). In most of the previously mentioned

things, the study reported on three ways

cases, dreams have inspired the lyrics of

music appeared in dreams reported by the

part or all of a song, rather than the music.

musician group: music dreamed exactly as

Examples include Johnny Cash’s “When

it is known in waking life (55%), music

the Man Comes Around,” Shawn Colvin’s

known but dreamed in an unusual version

“Polaroids,” Sting’s “The Lazarus Heart,”

(17%), and an entirely unknown piece of

and Bruce Cockburn’s “Wondering Where

music appearing in a dream (28%) (Uga,

the Lions Are.” The Internet site Song-

Lemut, Zampi, Zilli, & Salzarulo, 2006).

facts.com lists 51 popular songs inspired

Dreams have provided inspiration to both

by dreams (Songs Inspired by Dreams,

classical andpopularmusicians.Beethoven’s

n.d.). No doubt a complete list would run

canon “O Tobias,” Igor Stravinsky’s “Rite

into the hundreds, if not thousands.

of Spring,” Taitini’s “The Devil’s Trill So¬

It is interesting to consider what it means

nata,” and Wagner’s “Tristan and Isolde”

that we dream of music at all, when dreams

are among the classical works that owe their

are predominantly made up of pictorial im¬

existence to dreams (Barrett, 2001). Irving

ages. Stefano Carta addresses this question

Massey (2006) cites additional examples in

from the perspective of analytical psychol¬

“The Musical Dream Revisited.”

ogy, in which dreams are viewed as self¬

The Beatles ballad “Yesterday” is likely

representations. He argues that sound and

the most famous and commercially suc¬

music correspond to a more archaic level

cessful song to have come from a dream.

of psychological functioning than imag¬

Paul McCartney dreamed the melody, and

ery, and therefore music in dreams under¬

at first was certain he must have heard it

lies visual imagery, and may be the purest

before, feeling skeptical that such a lovely

expression of the emerging self. When

tune had truly originated in a dream. But

music shows up in a dream, the acoustic

after playing it for many people he became

emotional qualities contained in the music

convinced it was a true dream composi¬

can provide a foundation through which

tion, at which point he wrote the song’s

to interpret the dream’s visual imagery

hauntingly beautiful lyrics, which have

(Carta, 2009).

stood the test of time (Barrett, 2001; Grace, 2001). Other contemporary

In conclusion, it must be noted that only a small amount of research has been done


to date on the prevalence, meanings, im¬

have dream-inspired songs to their credit

plications, and applications of music in

include Sting, Johnny Cash, Patti Smith,

dreams. This area of study is still in its in-





Music and Dreams

fancy, offering many paths to explore and


much more to be discovered.

of dreaming (pp. 167-172). New York: Nancy Grace

References Barrett, D. (2001). The devil plays the vio¬ lin: Dreams and music. In The committee

and psychological


Palgrave. Massey, I. J. (2006). The musical dream revis¬ ited: Music and language in dreams. Psy¬ chology of Aesthetics, Creativity, and the Arts, 5(1), 42-50.

of sleep: How artists, scientists, and ath¬

Roseman, M. (1993). Healing sounds from the

letes use their dreams for creative problem¬

Malaysian rainforest: Temiar music and

solving—and how you can too (pp. 66-81).

medicine. Berkeley: University of Califor¬

New York: Crown Publishing.

nia Press.

Carta, S. (2009). Music in dreams and the emergence of the self. Journal of Analytical Psychology, 54, 85-102. Grace, N. (2001). Making dreams into music: Contemporary songwriters carry on an age-old dreaming tradition. In K. Bulkeley (Ed.), Dreams: A reader on the religious,

Songs inspired by dreams, (n.d.). Retrieved from the Song Facts website: http://www. songfacts.eom/eategory:songs_inspired_by_ dreams.php Uga, V., Lemut, M.C., Zampi, C., Zilli, I., & Salzarulo, P. (2006). Music in dreams. Con¬ sciousness and Cognition, 5, 351-357.

N Naps

or sustained operations; (3) pure appeti¬ tive drive, linked to sociocultural and in¬

Naps can be defined as short periods of

dividual characteristics. It is quite evident

sleep that can be taken at any time of the

that napping may be often considered a

24 hours.

pleasant activity, and many people report

Interestingly, there is no consensus yet

a psychological benefit for napping appar¬

on the maximum length for a sleep episode

ently independent from its physiological

to be defined a nap. In 1987, Dinges and

effects; (4) age-related polyphasic sleep-

colleagues proposed that a nap is shorter

wake rhythms, which occur in both infant

than half the habitual nocturnal sleep, but

and, to a lesser extent, elderly subjects.

almost all of the scientific literature puts the upper limit at two hours, or even one

How Frequent Are Naps?

hour, given the little feasibility of longer naps in most of the settings.

An overview of the most recent scientific

At variance with the vast majority of

literature shows that the overall prevalence

mammals, who are polyphasic sleepers

of napping ranges from approximately

(i.e., they have more than one sleep epi¬

10 to 65 percent. This large variance ob¬

sode, all over the 24 hours), humans tend

viously depends, on one hand, on the dif¬

to be monophasic in most cases, meaning

ferent instruments adopted (interviews,

that they concentrate waking time dur¬

diaries, objective measures) and, on the

ing the daytime/light hours and have only

other hand, on demographic characteristics

one major sleep period, usually placed at

of the population studied (age, nationality,

nighttime/dark hours.

sociocultural background).

However, there are exceptions to this

According to the 2005 National Sleep

general rule, and taking naps is a habit

Foundation poll on adults’ sleep hab¬

of several individuals. This habit can be

its, 55 percent of the general population

more or less frequent, and it can depend

in United States take a nap at least once

on a number of different reasons, includ¬

a week, and more than 10 percent at least

ing: (1) recuperative need, when the sleepy and fatigued subject has to recover from

four times a week. Within the United States, African Ameri¬

a previous sleep deprivation/restriction;

cans report more frequent napping than

(2) prophylactic strategies, which are

Caucasian individuals. The diffusion of

aimed at counteracting an expected sleep

napping behavior in the African culture

deprivation and to maintain performance

is supported by a very recent study find¬

in particular contexts such as shift work

ing high frequencies of habitual napping





in a sample of 276 Nigerian undergradu¬ ates, age range 19 to 35: 68.1 percent take

Naps and Health

one to three naps per week, 14.2 percent

Notwithstanding the widespread diffusion

take four to seven naps per week, with the

of napping, data on its impact on health are

mean duration of afternoon naps being

surprisingly scarce and generally limited to

70 minutes for males and 90 minutes for

elderly subjects. In elderly people, napping


has been reported to be associated with in¬

Independent from geographical origin,

creased risk of mortality, diabetes, falls,

prevalence studies also suggest that habit¬

and hip fracture. Furthermore, a relation¬

ual nappers are more likely to be males,

ship between napping and cardiovascular

with higher educational levels than non-

disease risk has often been highlighted,

nappers. Napping tends to be a very com¬

though it remains unclear, with several

mon phenomenon in children, as well. For

studies reporting an association, but not

example, in Saudi Arabia daytime naps

all, and a few studies even reporting that

were reported in 40.8 percent of the chil¬

napping may decrease coronary heart dis¬

dren aged 5 to 13, and a recent study found

ease risk, depending on nap duration and

that among a group of 27 children, whose

health status. Napping may also be associ¬

sleep was accurately controlled through

ated with increased risk of cognitive im¬

actigraphy, 32 percent reported daytime

pairment, particularly with compromised

naps, a prevalence increasing up to almost

executive function in older women. This

50 percent in those children affected by

last observation would seem at odds with


what will be said in a following section of

Finally, concerning older subjects, nap¬

this entry, which will highlight the positive

ping appears to be a quite common prac¬

impact of napping on cognition, especially

tice in community-dwelling older adults,

memory. However, it is important to dis¬

not necessarily detracting from nighttime

tinguish the potential beneficial effect of

sleep duration or quality. At least one nap

experimentally imposed naps on memory

per week was reported by 67.2 percent of

from the cognitive impairment associated

Chinese people aged more than 50, more

with the frequent napping of older adults in

commonly in the males (76.4%) than the

natural contexts. This contrast, along with

females (63.6%). Among these, 59.4 per¬

the conflicting findings mentioned previ¬

cent practiced daily. Similar prevalences

ously, clearly illustrates the complexity

have been obtained in elderly populations

of the interrelationships among napping,

of other geographical regions. This in¬

health, and cognition, which have yet to

crease of napping behavior across aging

be fully delineated. A further difficulty is

is likely the result of increases in night¬

that no specific causal relation can be in¬

time sleep disturbances, phase advance of

ferred from the whole bulk of data. Even

circadian rhythms, comorbid medical and

where clear associations emerge, it is im¬

psychiatric illnesses, and poor sleep habits,

possible to determine their direction. On

raising the question of how naps are related

one hand, as far as cardiovascular risk is

to subjects’ health conditions.

concerned, recent data show that heart rate



and blood pressure significantly increase

performance was shown to be a function

after awakenings, both from nocturnal and

of total daily time in bed independent of

daytime sleep, which would lead to an in¬

whether sleep was consolidated or split

terpretation of naps as protective against

into two parts. An important practical con¬

morbidity risk. However, it is more likely

sequence is that correctly timed split sleep,

that an increase in spontaneous napping, as

shown to have positive effects, or at least

generally observed with aging, represents

no negative consequences on neurobehav-

a consequence of lifestyle changes (above

ioral performance, might be used for sleep-

all, an increase of sedentariness), which in

wake schedules in work environments that

turn depend on health worsening. Indeed

involve restricted nocturnal sleep due to

it would probably be more useful to dis¬

critical task scheduling.

tinguish frequent, unplanned, longer naps,

Another major source of data is the

with a potential to negatively impact night¬

on-field studies on shift workers, clearly

time sleep quality and morbidity risk, from

showing that the alertness- and perfor¬

brief planned naps, which could instead be

mance-enhancing effects of naps during

of benefit to the function of older adults.

both night and afternoon shifts can be quite dramatic. It appears that a daytime nap as

Naps, Vigilance, and Performance

short as 10 minutes can improve alertness and performance of sleep-deprived sub¬

It is commonly accepted that sleep is nec¬

jects by about 2.5 hours and that short naps

essary for effective daytime functioning,

may even be beneficial in absence of sleep

especially in terms of vigilance and neu-

loss for those with moderately disturbed

rocognitive performance. Actually, in con¬

sleep and possibly for normal sleepers.

trast to the largely negative associations

To adequately adopt napping strategies

just described between habitual napping

as a part of programs aiming to improve

and general health, short-term laboratory

safety and health in the work place, some

studies generally report very beneficial ef¬

crucial aspects remain to be fully under¬

fects of a nap on these functions. There¬

stood: (1) what is the best nap duration to

fore, as mentioned in the previous section

achieve the most effective alerting effects:

“Naps and Health,” one common applica¬

it has been suggested that naps longer than

tion of naps would be to counteract vigi¬

45 minutes could be detrimental because

lance reduction in the work environment,

they would be frequently associated with

when prolonged operations (and thus,

awakenings from deep sleep, which in turn

sleep deprivations) are required.

result in a higher degree of sleep inertia

First of all, there have been intrigu¬

(i.e., experience of drowsiness and worsen¬

ing laboratory studies trying to clarify

ing of cognitive performance occurring at

whether a given amount of sleep can pro¬

awakening); (2) the possible combination

vide the same beneficial effects for vigi¬

with other behavioral or pharmacological

lance and performance when split into two

strategies (such as caffeine), to maximize

or more shorter episodes (split-sleep regi¬

alertness at crucial time points as a coun¬

mens). Results were encouraging, in that

termeasure to sleepiness in operational





shift work; (3) how neurocognitive effects

consolidation, more robust effects seem

of naps may be modulated by individual

to be given by slightly longer naps, about

variables (i.e., chronotypologies) and as a

60 to 90 minutes, likely due to the buildup

function of their circadian placement: for

of both short-wave sleep and REM sleep.

example, taking a nap too late in the day

The possible roles of sleep-states amount,

might deeply affect night-sleep continuity

sleep continuity, and organization remain

and make it difficult to fall asleep at habit¬

to be verified, as well the hypothesis that a

ual bedtime, whereas taking it in the morn¬

memory-enhancing process is triggered by

ing hours could be hampered by the low

sleep onset per se.

circadian sleep propensity (i.e., the rising

The purported beneficial impact of naps

curve of body temperature would result in a

on memory should deserve special atten¬

short, fragmented and possibly ineffective

tion at early ages, because this might be of

nap); finally, (4) whether and how differ¬

interest with respect to learning processes

ent cognitive functions (attention, working

and school performance. A final statement

memory, higher cognitive functions such

could be made on oneiric activity during

as decision making and planning) are dif¬

naps. Occasionally, the presence of dream

ferentially influenced by napping.

recall has been found after all awakenings from nap, with longer recalls after REM

Naps, Memory, and Dreams

awakenings than after NREM awakenings. However, it is still unknown how the con¬

According to studies carried out in the last

tents of dream during naps may differ from

10 years, the facilitating role of sleep for

those of night-sleep dreams.

memory consolidation of what is learnt before sleep (the so-called sleep effect) would be observed even for the short sleep

Gianluca Ficca

See also: entries related to Sleep and Develop¬ ment; entries related to Sleep Assessment

episodes. Quite surprisingly, and differ¬ ently from what has been reported for the


night-sleep effect, a beneficial nap effect

Dhand, R., & Sohal, H. (2006). Good sleep, bad sleep! The role of daytime naps in healthy adults. Current Opinion in Pulmonary Med¬ icine, 12, 379-382.

was consistently found for any kind of memory (i.e., both procedural and declar¬ ative tasks). However, the effect strength ranges from quite dramatic changes, even including the actual improvement of mem¬ ory performance at awakening, to less rel¬ evant modifications, usually limited to a reduction of the forgetting/deteriora¬ tion rate, which seemingly depends on numerous factors, either related to sleep or memory. Although there is not yet a clear knowledge of what sleep features are crucial for the nap effect on memory

Dinges, D. F., Ome, M. T., Whitehouse, W. G., & Orne, E.C. (1987). Temporal placement of a nap for alertness: contributions of cir¬ cadian phase and prior wakefulness. Sleep, 10(4), 313-329. Ficca, G„ Axelsson, J., Mollicone, D. J., Muto, V., & Vitiello, M.V. (2010). Naps, cogni¬ tion and performance. Sleep Medicine Re¬ views, 14, 249-258. National Sleep Foundation (NSF). (2005). Adult sleep habit: 2005 poll. Retrieved from http://www.sleepfoundation.org/

Narcolepsy and Dreaming

Picarsic, J.L., Glynn, N.W., Taylor, C.A., Katula, J.A., Goldman, S.E., Studenski, S.A., & Newman, A. B. (2008). Selfeported napping, sleep duration and quality in the Lifestyle Interventions and Indepen¬ dence for Elders Pilot (LIFEP) Study. Jour¬ nal of the American Geriatric Society, 56, 1674-1680. Takahashi, M. (2003). The role of prescribed napping in sleep medicine. Sleep Medicine Reviews, 7, 227-235.


alternative treatment modalities for narco¬ lepsy included electroshock therapy and psychosurgery. Before the use activating medications for narcolepsy became ac¬ cepted in the 1930s, many narcoleptics un¬ derwent extensive psychoanalysis. Freud postulated that dreams were protectors of sleep, with sleep viewed as a temporary escape from harsh reality into a memory of protected intrauterine nirvana. Psychodynamically, narcolepsy became viewed as a disease of psychological regression.

Narcolepsy and Dreaming

Theoretic constructs based on repression, abuse, mythology, and transference served

Narcolepsy is a neurological illness occur¬

as a basis for attempts at intense interper¬

ring secondary to damage to central ner¬

sonal therapy for patients with the diag¬

vous system (CNS) cells utilizing oxexin

nosis. However, there is little evidence,

as their primary neurotransmitter. Narco¬

even based on anecdotal case studies, that

lepsy patients present with symptoms of

psychoanalysis led to an improvement in

extreme daytime sleepiness usually de¬

patient symptoms or affected the course

velop these symptoms during the psy¬

of the illness for individual patients in a

chologically and sexually stormy years of

positive fashion (Pagel & Scrima, 2010,

adolescence. Most narcoleptics are intense

pp. 129-134). Community and medical

dreamers who often experience dream¬

conceptions of narcolepsy continue to be

like epiphenomena, including hypnogogic

affected by this psychogenic history with

hallucinations and sleep paralysis. In 50

the diagnosis viewed as one based on sup¬

percent of narcoleptics, REM-sleep intru¬

pressed, guilt-ridden, sexual drives. This

sion into wakefulness results in symptoms

conceptual association may contribute to

of cataplexy—abrupt episodes of motor

social and medical handicaps for some

weakness occurring with emotion.

narcolepsy patients with physicians and

Narcolepsy was first described as a diag¬

cohorts demonstrating a lack of under¬

nosis during a period when diseases such

standing and on occasions taking a moral

as narcolepsy and epilepsy, now known to

stance in labeling them as “lazy, unable to

have clear neurological basis, were clas¬

work, or unable to face the vicissitudes”

sified among the psychoses and neurosis.

(Zarcone, 1973, pp. 1156-1168).

Freud’s first book on dreaming, published

In the current era, narcolepsy is clearly a

in 1900, led to a psychoanalytic fascina¬

neurological illness with a well-defined ge¬

tion with the dreamlike epiphenomena

netic and neurotransmitter basis. Psycho-

of narcolepsy. It is not surprising that

analysis-based therapy is rarely used in its

psychoanalysis was used to treat narco¬

treatment; however, this history continues

lepsy, particularly during an era in which

to affect social and medical attitudes toward




Narcolepsy and Sleep Paralysis, Hypnopompic/Hypnagogic Hallucinations

patients. While psychoanalysis has failed

psychodynamically primitive state of CNS

as a treatment and psycho-pathogenesis as

activation parodying the psychoanalytic id

a model when applied to the clinical di¬

persists in modern versions of activation-

agnosis of narcolepsy; the psychoanalytic

synthesis theory, including the activation,

theory of narcolepsy, as well as the associa¬

input, modulation model (Hobson, 1999,

tion of narcolepsy with REM-sleep epiphe-

pp. 188-215). While today, psychoanalysis

nomena, has been integrated and applied

is only rarely utilized in the clinical treat¬

in forming the conceptual framework for

ment of narcolepsy, psychoanalytic per¬

some of the most widely accepted neuro¬

spectives of the dreamlike epiphenomena

scientific theories of consciousness. Nar¬

of narcolepsy continue to be incorporated

colepsy epiphenomena were postulated to

into popular and theoretical conceptions of

be related to normal dreaming since they

dreaming, sleep, and consciousness. James F. Pagel

were associated with REM sleep, a state that theoretically came to be equated with the presence of dreaming. This associa¬

See also: entries related to Sleep Disorders

tion between REM sleep, narcolepsy, and


dreaming forced psychoanalysts to stretch the definition of dreaming to include the

Crick, F., & Mitchinson, G. (1983). The func¬ tion of dream sleep. Nature, 304, 111-114.

REM sleep associated with bizarre, hallu¬

Hobson, J. A. (1999). Abnormal states of con¬

cinatory mental activity of narcolepsy that

sciousness: AIM as a diagnostic tool in con¬

could occur in both sleep and wake states. This definition, “bizarre mental activity occurring in either sleep or wake,” is cur¬ rently the generally accepted psychoana¬ lytic definition of dreaming (Pagel et al., 2001, pp. 195-202). This postulate, that dreams are bizarre, hallucinatory mental activity, has been extended into the the¬ ory that dreams are a form of visual hal¬ lucination and a valid model for psychosis. Dreaming viewed as perceptual hallucina¬

sciousness. New York: Scientific American

Library. Pagel, J.F., Blagrove, M., Levin, R., et. al. (2001). Defining dreaming—A paradigm for comparing disciplinary specific defini¬ tions of dream. Dreaming, 11(4), 195-202. Pagel, J.F., & Scrima, L. (2010). In M. Goswami, S.R. Pandi-Perumal, & M. Thorpy (Ed.). Psychoanalysis and narcolepsyin narcolepsy—A clinical guide (pp. 129134). New York: Springer/Humana Press. Zarcone, V. (1973.) Narcolepsy. New England Journal of Medicine, 288, 1156-1168.

tion can be considered as a simple mean¬ ingless, perceptual state based on primitive brain-stem activity (REM sleep of the selfreferenced mind utilized by the CNS during sleep to detoxify the system of unwanted

Narcolepsy and Sleep Paralysis, Hypnopompic/ Hypnagogic Hallucinations

memories of potentially pathological na¬ ture such as obsessions, hallucinations,

Narcolepsy is a rare and chronic sleep dis¬

and delusions [Crick & Mitchinson, 1983,

order affecting approximately 0.04 percent

pp. 111-114]). The conception of REM

of the population. Narcoleptic patients ex¬

dreaming as bizarre and REM sleep as a

perience excessive daytime sleepiness,

Narcolepsy and Sleep Paralysis, Hypnopompic/Hypnagogic Hallucinations


cataplexy, and manifestations related to

experience a brief loss of voluntary muscle

rapid eye movement (REM) sleep, such as

control with an inability to move or speak;

sleep paralysis and hypnopompic/hypna-

however, awareness is preserved. Unlike

gogic hallucinations. The loss of a central

cataplexy, these episodes are not provoked

nervous system peptide called hypocretin

by intense emotional states. It can be a

is the reason for the development of narco¬

frightening experience because the indi¬

lepsy. Hypocretin has important functions

vidual attempts to, but is unable to move,

in promoting wakefulness. Excessive day¬

open eyes, or even speak, and is very aware

time sleepiness, sleep paralysis, and hyp-

of this occurrence. Sleep paralysis is often

nopoinpic/hypnagogic hallucinations can

associated with very frightening hypno-

also occur in individuals who are severely


sleep deprived; only cataplexy is unique to

episodes are brief lasting several seconds


to minutes, and with time, the experience

Sleep-wake-cycle instability is an im¬



becomes less frightening.

portant hallmark of narcolepsy, specifi¬

Hypnopompic/hypnagogic hallucinations

cally between REM sleep and wake states.

are intense dreamlike states that occur at

Sleep paralysis and hypnopompic/hypna-

sleep onset (hypnagogic) or more com¬

gogic hallucinations are a consequence

monly upon awakening (hypnopompic).

of REM sleep-wake-cycle instability. In

Like normal dreams, hallucinations are vi¬

REM sleep, the body loses muscle tone and

sual in nature, but unlike normal dreams,

dreaming occurs. During this physiologi¬

they are vivid, frightening, or disturbing

cally normal process, essentially all muscles

to the individual. They may involve other

of the body are paralyzed with the excep¬

senses such as hearing or smell. Visual

tion of the diaphragm, the primary muscle

hallucinations consist of simple forms and

of breathing. In narcoleptic patients, REM

shapes to very intricate images including

sleep is considered to be unstable because

animals or people. Auditory hallucinations

it inappropriately intrudes into their waking

may be threatening, leaving the individual

states. In other words, REM sleep seems to

upset or terrified. Individuals may report

be inappropriately jumping into wakeful¬

hallucinations such as body floating in air,

ness, causing the individual to be paralyzed

falling from air, or out-of-body experi¬

while awake. Narcoleptic patients experi¬

ences. The exact boundary between hyp¬

ence some aspects of REM sleep during

nopompic/hypnagogic hallucinations and

wakefulness (such as loss of muscle tone

dreams is not a clear one.

as seen in cataplexy) or during transitions

Treatment of narcolepsy includes medi¬

from sleep to wake states (sleep paralysis).

cations that suppress REM-sleep instabil¬

Sleep paralysis is the inability to pur¬

ity and prevent daytime sleepiness. These

posefully move one’s muscles at sleep

medications will also treat sleep paralysis

onset or upon awakening. In sleep paraly¬

and hypnopompic/hypnagogic hallucina¬

sis, componenls of REM sleep occur inap¬

tions in the same manner by stabilizing

propriately as the individual falls asleep or

REM sleep. One category of antidepres¬

awakens. Individuals with sleep paralysis

sants known as selective norepinephrine/




Narcolepsy Symptoms, Abnormal REM Sleep, and Hypocretin Deficiency

serotoninergic reuptake inhibitors is used to treat narcolepsy with cataplexy and is effective for sleep paralysis and hypnopompic/hypnagogic hallucinations.


most commonly used drug of this class is venlafaxine, a potent inhibitor of two wake-promoting chemicals in the brain: serotonin and norepinephrine. New treat¬ ment options are under investigation for the treatment of narcolepsy including hypocretin replacement therapy, gene ther¬ apy, and stem-cell transplantation. It is important to remember that sleep paralysis and hypnopompic/hypnagogic hallucinations are present in other sleep-

Nishino, S., Okuro, M., Kotorii, N., et al. (2010). Hypocretin/orexin and narcolepsy: New basic and clinical insights. Acta Physiologica, 198, 209-222. Ohayon, M.M., Priest, R.G., Caucet, M., et al. (1996). Hypnagogic and hypnopompic hal¬ lucinations: Pathological phenomenon? Brit¬ ish Journal of Psychiatry, 169, 459-467. Rechtschaffen, A., Wolpert, E., Dement, W. C., et al. (1963). Nocturnal sleep of narcolep¬ tics. Electroencephalography and Clinical Neurophysiology, 15, 599-609. Takahashi, Y., & Jimbo, M. (1963). Poly¬ graphic study of narcoleptic syndrome with special reference to hypnagogic halluci¬ nations and cataplexy. Folia Psychiatrica Neurologica Japan, 7(Suppl), 343-347.

related disorders, including any condi¬ tion that causes severe sleep deprivation. The two phenomena also commonly occur in the general population. Medications used for narcolepsy will also treat sleep

Narcolepsy Symptoms, Abnormal REM Sleep, and Hypocretin Deficiency

paralysis and hypnopompic/hypnagogic hallucinations; however, they are not rec¬

Narcolepsy, a condition affecting about 1

ommended as treatment for isolated sleep

in 2,000 individuals, is caused by the auto¬

paralysis and/or hypnopompic/hypnago¬

immune destruction of ~70,000 hypotha¬

gic hallucinations. If an individual experi¬

lamic neurons producing the neuropeptide

ences recurrent episodes of sleep paralysis

hypocretin/orexin, a neurobiological sys¬

and/or hypnopompic/hypnagogic halluci¬

tem involved in sleep regulation. Since its

nations, it is recommended that he or she

description, the disorder has fascinated re¬

be evaluated for the presence of an undi¬

searchers and clinicians, notably because

agnosed sleep-related disorder, such as ob¬

patients experience not only sleepiness and

structive sleep apnea or narcolepsy.

disturbed sleep but also unusual symptoms

Michelle Cao

such as cataplexy, sleep paralysis, REM sleep behavior disorder (RBD), and hyp¬

See also: entries related to Sleep and Health;

nagogic hallucinations,

entries related to Sleep Physiology

are best explained by a blurring of wake¬

References Cao, M. (2010). Advances in narcolepsy. Medical Clinics of North America, 94(3),

541-555. Dauviliers, Y., Arnulf, I., & Mignot, E. (2007). Narcolepsy with cataplexy. Lancet, 369, 499-511.

symptoms that

fulness with rapid eye movement (REM) sleep. In sleep paralysis and cataplexy, monosynaptic reflexes are abolished, as they are during REM sleep, suggesting the engagement similar final common neuroanatomical pathways. Similarly, RBD, vivid dreaming, and hallucinations are

Narcolepsy Symptoms, Abnormal REM Sleep, and Hypocretin Deficiency


commonly referred as dissociated REM-

be due to the difficulty of identifying this

sleep events, in which the cardinal features

symptom in young children.

of REM-sleep atonia, vivid dreaming, and

It is also notable that around the onset

loss of awareness are uncoordinated with

of narcolepsy, spontaneous muscle weak¬

each other. Narcolepsy is thus an experi¬

ness episodes affecting the jaw or head, or

ment of nature, in which unique subfea¬

a generalized feeling of weakness with an

tures of REM sleep can be isolated and

unstable gait are commonly reported rather

subjected to investigation.

than typical cataplexy.



Part of the narcolepsy phenotype is di¬

months are required before cataplexy be¬

rectly caused by the removal of the effects

comes stereotyped and triggered by usual

of hypocretin/orexin on REM sleep and

emotions—laughing or humor. These suc¬

wake propensity. Indeed, pharmaceutical

cessive changes suggest that cataplexy is

studies using antagonists or agonists sup¬

the result of network remodeling, perhaps

port this concept, as does the common ob¬

to compensate for what was initially a

servation of reduced REM-sleep latency

more-generalized muscle weakness. Sim¬

and the presence of sleepiness in narco¬

ilarly, whereas abnormal dreaming in re¬

lepsy. Importantly, however, the phenotype

cent onset narcolepsy immediately impairs

of narcolepsy cannot be recapitulated by

sleep, the occurrence of prolonged night¬

REM sleep or total sleep deprivation alone.

time awakenings often occurs later once

Shortened REM sleep, sudden dreaming,

the full syndrome is established. This may

hypnagogic hallucinations, or sleep paral¬

be explained by the delayed engagement

ysis may occur following sleep deprivation

of compensatory wake-promoting systems

or sleep fragmentation; in contrast, cata¬

that could be equally functioning at night

plexy has never been reported under these

and during the day.

conditions. This suggests that cataplexy is

As noted by many authors, the projec¬

somewhat uniquely different from REM-

tions of the hypocretin system are anatomi¬

sleep atonia, a concept also supported by

cally widespread, providing the anatomical

differential neurochemical control in phar¬

basis for independent effects on selected

macological studies.

REM sleep and non-REM sleep correlates.

Much has also been learned from re¬

For example, hypocretin projections to

cent observations on the natural history of

the sublaterodorsal tegmental nucleus (an

the disease. Following the development of

REM sleep-on region of the brain stem),

hypocretin deficiency in narcolepsy, sleep¬

the locus coeruleus, or even the spinal cord

iness and abnormal dreaming are usually

could all be involved in the regulation of

first to appear, followed by cataplexy and a

REM-sleep atonia, whereas projection to

distressing inability to maintain sleep. Ex¬

the basal forebrain may be more important

cessive sleep is also common shortly after

for forebrain activation. It is not unreason¬

onset, subsequently replaced by an inability

able to postulate that differential redun¬

to stay awake and asleep for long periods

dancy (and thus variable compensation

of time. Sleep paralysis is less-commonly

after depletion) occurs for hypocretin pro¬

reported prior to puberty, a finding that

jections regulating individual REM-sleep

may reflect a maturational effect or could

features. This compensation is also likely




Native American Dreams

more effective depending on the state of engagement of these systems in other tasks. For example, the reversal of atonia may be most difficult in wakefulness and

Serra, L., Montagna, P., Mignot, E., Lugaresi, E., & Plazzi, G. (2008). Cataplexy features in childhood narcolepsy. Movement Disor¬ ders, 23(6), 858-865.

during sleep-wake transitions, explaining sleep paralysis. Similarly, a pathway com¬

Native American Dreams

pensating for atonia may also be uniquely challenged when laughing, an act report¬

Among indigenous peoples, dreams and

edly associated with a brief suppression of

dreaming are highly valued and often in¬

the spinal monosynaptic H reflex. One of

corporated into ritual practices. Dreams

the candidates for this last pathway could

are a primary source for cultural innova¬

involve adrenergic activation, as adren¬

tion, ritual renewal, communal activities,

ergic uptake inhibitors (i.e., some antide¬

and personal guidance. With more than

pressants) are profoundly anticataplectic

140 recognized Native American commu¬

agents. Further, stimulation of the locus

nities, each speaking a diverse language,

coeruleus seems to gate some of the hypo-

dream categorization and theory is com¬

cretin effects following optogenetic stimu¬

plex and irreducible to any single metathe¬

lation, in particular muscle atonia.

ory or specific cosmology. Overall, the

As illustrated previously, narcolepsy is

emphasis tends to be on the value of the

a unique experiment of nature that has yet

dream as empowering actions that serve

to reveal its full potential as a tool to un¬

the needs of the community. In many com¬

derstanding various aspects of REM-sleep

munities, dreams are indexed typologically

circuitry and its plasticity in response to

in terms of the degree of power transmit¬

hypocretin depletion. Imaging studies in

ted to the dreamer. For example, among the

dissociated states, may, for example, pro¬

Apsarokee dreams are analyzed into four

vide us with a better understanding one day

primary categories (Irwin, 2005a, 2005b):

of how the brain is or is not aware dur¬

no account (most dreams), wish fulfilling

ing REM sleep, and why the experience

(compensatory dreams), medicine dreams

of dreaming is normally so rapidly for¬

(power is given to the dreamer), and what

gotten (or in abnormal instances patho¬

is truly seen (dreams of knowledge often

logically retained). Similarly, optogenic or

linked to a variety of psychic abilities, in¬

localized genetic rescue experiments in re¬

cluding clairvoyance and controlled out-

ceptor knockout narcoleptic animals will

of-body projection). Medicine dreams are

likely improve our understanding of REM-

rare and given utmost attention as a source

sleep-regulating networks.

of success in life; what is truly seen dreams

Emmanuel Mignot

See also: entries related to Hormones in Sleep

usually occur to only developed shaman dreamers. Medicine dreams that confer some de¬


gree of power or ability are attained in

Bassetti, C., Billiard, M., & Mignot, E. (2007). Narcolepsy and hypersomnia. New York: Informa Healthcare.

three ways: spontaneously and unsought, spontaneously in times of crisis linked to prayer and petition to the spirit world,

Native American Dreams


and sought dreams or visions through in¬

success based on the match between the

tense ritual practices. The source of the

communal need and the specific ability of

dream is usually mapped to the cosmo¬

the dreamer. Someone with a specific ill¬

logical and spiritual world of the seeker in

ness may not be healed because the gift of

which causal agents are identified as giv¬

healing is meant only for certain types of

ing a dream of power as a gift from the

illness; or, a dreamer is given diagnostic

spirit world. The appropriate attitude of

power in the dream but may not be able to

the dreamer in seeking a dream is humility,

diagnose correctly if an illness exceeds the

clear intention, and thankfulness; dreams

knowledge given in the dream. Dreamers

are sought by shedding tears (occasion¬

may fast for additional dream powers and

ally blood, e.g., cutting a finger) and pray¬

those who failed in a dream quest may try

ing intensely without food or water over

again. Dream powers given may include

many days while often confined within a

hunting ability, success in warfare, psychic

12-foot fasting circle. The seeker walks

abilities, herbal knowledge, ritual direc¬

toward each of the four directions, with

tions and songs, as well as various types of

small steps, holding a pipe and praying

ambiguous power that might harm others.

with each step. Vision-dreams may come

Another major dream category is prophetic

while the faster is asleep or wide awake.

dreams, which are the source of many na¬

Other traditions involve confinement in a

tive religious movements based on in¬

fasting hut (often for women), in a tree, or

structions received in big dreams meant to

while wandering without eating in the for¬

reconstruct native religious practices and

est. The seeker is usually observed by an

beliefs in the face of colonialism, mission-

experienced elder dreamer who can assess

ization, and aggressive assault by church

the state and well-being of the faster. The

and government (Irwin, 2008). More re¬

ritual fast is normally preceded by a sweat

search is needed in the area of specific

lodge before and after the fast; in the final

dream practices in contemporary native

sweat, dreams are shared and interpreted

urban life and in prisons.

by elders in utmost privacy. Generally, a dreamer does not discuss a dream with others except with dream experts or with

Lee Irwin

See also: entries related to Cross-Cultural Dreams

members of a dream society based on those having similar dreams (Irwin, 1994).


The proof of the dream is in the enact¬

Irwin, L. (1994). The dream seekers: Native

ment. As dreams are considered sources of

American visionary traditions of the Great

sacred power, the successful dreamer must be able to give a public demonstration of that power. Failure to heal after dreams of healing signals a discontinuity between the dreamer aftd the causal agency of the dream; repeated failure means the dream was not understood. Native dream theory incorporates some degree of variability of

Plains. Norman: University of Oklahoma

Press. Irwin, L. (2005a). Dreams and visions. In S. Crawford & D Kelly (Eds.), Encyclopedia of American Indian religions (Vol. 1, pp. 240-249). Santa Barbara, CA: ABC-CLIO. Irwin, L. (2005b). Vision quest rites. In S. Crawford & D Kelly (Eds.), Encyclope¬ dia of American Indian religions (Vol. 3,




Neural Metaphor and Dreams

pp. 1127-1134). ABC-CLIO.




primary metaphors neurally bind with each other and other concepts to form many

Irwin, L. (2008). Coming down from above:

thousands of conceptual metaphors, all

Prophecy, renewal and resistance in Native

physically in the brain, all mapping infer¬

American religions. Norman: University of

Oklahoma Press.

ences from source to target domains, and all fixed and ready to be unconsciously ac¬ tivated whether you are awake or dreaming. Primary metaphors are embodied in

Neural Metaphor and Dreams

three ways: they arise from bodily experi¬ ences, they are physically in the brain, and

In the three decades since the discovery

they give rise to physical behavior, as re¬

that ordinary thought is largely metaphori¬

cent experiments on embodied cognition

cal, metaphor researchers have come to

have shown. Subjects at Yale University

understand that, like all other concepts,

were given either warm or cold coffee and

conceptual metaphors are physical circuits

then asked to describe someone they imag¬

in the brain. Primary metaphors are ac¬

ined just meeting. Those who had the warm

quired by the hundreds in childhood, often

coffee imagined meeting friendly, affec¬

prior to language, just by living in the ev¬

tionate people. Affection is warmth was ac¬

eryday world, where different kinds of ex¬

tivated by the warm coffee. Subjects who

periences often come together.

were asked to say nasty lies about other

Every time a child is held affectionately

people chose to either wash their hands or

by a parent, the child experiences affection

use cleansing wipes afterward. The moral¬

and warmth together, and he or she acti¬

ity is purity metaphor was at work. And so

vates different brain regions. Every time a

on for dozens of experiments.

child sees more water or milk poured into

In dreams, concerns and experiences of

a glass and sees the level rise, distinct brain

the day tend to activate preexisting meta¬

regions for quantity and verticality are ac¬

phor circuitry to produce dreams of rele¬

tivated. When two brain regions are acti¬ vated repeatedly, their synapses strengthen,

vance to the concerns most active in one’s brain during the day.

activation spreads over existing pathways,

A woman dreamt that she was walk¬

with synapses strengthening every time the

ing on a dirt road that became narrower

two regions are activated together. Even¬

and narrower, then became an uphill trail

tually, the shortest pathway is found, and

through dense brush. She climbed to the

a circuit is formed. That circuit is a meta¬

top of the hill where she saw an anthro¬

phor physically in the brain. That is how

pology professor of her acquaintance com¬

primary metaphors such as affection is

ing out of Trader Joe’s. “Don’t bother,” he

warmth and more is up are formed.

Hundreds of primary metaphors are

said. “The anthropologists have cleaned out the place.”

learned in this way. Because 98 percent

She had, after years of motherhood, got

of thought is unconscious, the use of such

a PhD in anthropology, but could not get

metaphors usually goes unnoticed. The

a regular job, only teaching a class here

Neuroanatomical Correlates of Dream Censorship


and there. She was about to give up and

where there is a conflict between the met¬

go into another profession. Trader Joe’s is

aphors for strictness versus nurturance.

the place where the local academics buy party goods. The dream activated wide¬ spread conceptual metaphors: a career

George Lakoff

See also: entries related to Dream Content

is a journey upward (climbing the ladder


of success); dijficulties are impediments

Lakoff, G. (1993, June). How metaphor struc¬ tures dreams: The theory of conceptual met¬ aphor applied to dream analysis, Dreaming.

to motion (roadblocks, glass ceilings); achieving as purpose is getting a desired object, typically food (as in the fruits of

one’s labor). In the dream, her career path was long and difficult, it narrowed, the uphill climb was difficult. An academic job in anthropology would have been the fruit of her labor, but the fruit was all taken.

Lakoff, G. (1996). Moral politics. Chicago: University of Chicago Press. Lakoff, G. (1997). How unconscious meta¬ phorical thought shapes dreams. In D. J. Stein (Ed.), Cognitive science and the Un¬ conscious. American Psychiatric Press.

A friend was distraught after splitting up

Lakoff, G., & Johnson, M. (1980). Metaphors we live by. Chicago: University of Chicago Press.

with his lover. He dreamed that night that

Lakoff, G., & Johnson, M. (1999). Philoso¬

they had started driving north on a local

phy in the flesh: The embodied mind and its

freeway. As they reached the freeway bridge, a storm blew up and the bridge was

challenge to Western thought. New York:

Basic Books.

blown into the bay. The widespread metaphors here are love is a journey—in which difficulties are an

impediment to motion—and emotional

Neuroanatomical Correlates of Dream Censorship

states are weather states. The lovers start

out on their journey, emotional storms

The term censor was coined by Sigmund

arise, and the bridge blown out makes the

Freud to denote the critical and prohib¬

journey of life impossible.

iting agency in the mind. Since the es¬

Much of child rearing is based on met¬

tablishment of the structural model of

aphors of morality that shape family life.

personality, Freud gradually replaced this

The two most prominent are morality is

term with the term superego to reify the

obedience, giving rise to a strict father

roles of this prominent entity of the mind

family, and morality is nurturance, giving

in both nocturnal and daytime psychic life.

rise to a nurturant parent family. The obe¬

The censor or superego is acquired largely

dience metaphor makes the strict father the

from experiences and interactions with

moral authority in the family whose word

significant others. It begins to develop in

is law and who has to physically punish

the oedipal phase (around three years of

all of children’s wrongdoings. Therapists

age) when the ego learns to master the in¬

have reported to me that bad dreams and

stinctual impulses arising from the id in a

corresponding neuroses result, especially

bid to preserve the object relation via the




Neuroanatomical Correlates of Dream Censorship

mechanisms of identification and reaction

apathy, and sociopathic behaviors. It has

formation. The primary purpose of the cen¬

also been observed that people with antiso¬

sorship is to screen out disagreeable ideas,

cial disorders or moral dysfunctions show

memories, and motives before they enter

neurological symptoms of autonomic and

into the conscious or preconscious system.

emotional underarousal, and lower fear¬

During sleep, however, this censorship

fulness, poor fear conditioning, and poor

function becomes weaker, thus allowing

avoidance learning. Accordingly, it may

material from the id to surface in the form

be the case that emotional and autonomic

of dreams.

arousal constitutes the structural bedrock

The censorship or moral function is an

for conditioning, which is critical for the

intricate process in both the psychody¬

development and maintenance of moral

namic and the neurodynamic senses. It is

and inhibitory functions. The orbitofron¬

the amalgam of primitive inclination and

tal cortex clearly functions for primitive

adaptation and of acquired self-monitoring

inhibition and morality, not necessarily

and moral reasoning. Nevertheless, the

sustained by logical scaffoldings; instead,

most basic form of the censor or super¬

under the predisposition of genetic pro¬

ego can be conceived as a mental agency

gramming and alterations, it is modulated

that inherits basic sensitivity to emotions;

and maintained through social affective in¬

in particular, to anxiety (1). Therefore, it

teractions and stimulus-response learning.

is capable of detecting error, danger, or

This primitive inhibitory and moral func¬

punishment (2), and is able to develop and

tion, which can transpire unconsciously, is

learn through behavioral and social condi¬

a pivotal part of the censor.

tioning (3). As such, it can make decisions


prefrontal convexity—including

as to whether or not to inhibit directly (4) or

the orbitofrontal cortex—is deactivated

it can trigger other mechanisms to defend

throughout the sleep cycle, while the me¬

against dangerous or punishable imme¬

sial frontal region—the neural substrate

diate satisfaction (5), to avoid the nega¬

for the instinctual reservoir—are highly

tive consequence resulting from doing so

active (for details see Yu, 2001, 2003,

(6). In this sense, the censor may influence

2007). This neuropsychological manifes¬

the process of dream formation but is not

tation is reminiscent of Freud’s descrip¬

necessarily the agency that carries out the

tion that the censor is crippled during

dream formation or distortion.

dreaming sleep and thus its governance

According to Yu (2003, 2006), all fore¬

over the id energies is loosened. It should

going six functional features of the censor

be noted, however, that although the pre¬

can be localized in the orbitofrontal cortex.

frontal cortex is significantly deactivated,

It has been known that lesions in this region

activity is still present—in other words, it

of the brain lead to a group of disorders re¬

remains operative. On the strength of the

lated to moral and affective functioning,

neuroimaging findings, Braun et al. (1997)

including poor judgment, moral confu¬

hypothesized that REM episodes occur¬

sion, misinterpretation of the moods and

ring later in the sleep period would be

feelings of others, empathic changes and

characterized by increasing coherence of

Neuroanatomical Correlates of Dreamwork

prefrontal, dorsomedial thalamic, and stri¬ atal activity, which could in turn correlate with the time-of-night-dependent changes in the length and complexity of REMsleep dream reports. Indeed, the level of activation or deactivation of the prefrontal cortex may change across different REM episodes within one sleep epoch and grad¬ ually recover its normal activity from its lowest point in the first REM episode, via progressive activation in the intermediate REM episodes, to its full convalescence


frontal region controversy (dream instiga¬ tion). Neuro-Psychoanalysis, 3, 193-201. Yu, C.K.-C. (2003). Neuroanatomical cor¬ relates of dreaming, III: The frontal-lobe controversy (dream censorship). NeuroPsychoanalysis, 5, 159-169. Yu, C.K.-C. (2006). Commentary on Simon Boag’s “Freudian dream theory, dream bi¬ zarreness, and the disguise-censor contro¬ versy.” Neuro-Psychoanalysis, 8, 53-59. Yu, C.K.-C. (2007). Cessation of dreaming and ventromesial frontal-region infarcts. NeuroPsychoanalysis, 9, 85-92.

in postsleep waking. By implication, not only is this vigilant agency never totally quiescent during all REM episodes, it also gradually recuperates from deep relax¬

Neuroanatomical Correlates of Dreamwork

ation and becomes highly alert toward the end of sleep.

Sigmund Freud (1900) believed that the

Contemporary brain-imaging research

manifest content of dreams was not nec¬

has resulted in a consistent picture of the

essarily the direct representation of the

neural network of dreaming. While the

dreamers’ thoughts and motives. He delin¬

most robust activity in the mesial frontal

eated some dreamwork processes through

region is observed in dreaming sleep and

which the latent dream thoughts are trans¬

the most precipitous decreases are found

formed into the manifest content. The most

in the prefrontal cortex, the most tranquil

prominent of these distortion processes are

moment of the mesial frontal region oc¬

regression, condensation, displacement,

curs in presleep wakefulness, while at the

and symbolism. On the strength of neu¬

same time the prefrontal cortex is most ac¬

roanatomical evidence, some researchers

tivated. These oscillatory neurodynamics

(Solms, 1997; Yu, 2001, 2006) postulate

between the prefrontal and subcortical ac¬

that dreamwork is orchestrated by the neu¬

tivities seem to mirror the psychodynamics

ral network made up of the prefrontal cor¬

between the censor and the id.

tex, the supramarginal gyrus in the inferior

Calvin Kai-Ching Yu

parietal lobule, and the inferior mesial tem¬ poral lobe.

References Braun, A. R., Balkin, T.J., Wesensten, N.J., Carson, R.E., Varga, M., Baldwin, P., . . . Herscovitch, P. (1997). Regional cere¬ bral blood flow throughout the sleep-wake cycle. Brain, *120, 1173-1197. Yu, C.K.-C. (2001). Neuroanatomical cor¬ relates of dreaming, II: The ventromesial

The growth of the prefrontal cortex, which continues after birth and does not end until late adolescence, is susceptible to environmental modifications. As the prefrontal cortex develops, a child’s be¬ havior begins to become subordinated to logical reasoning, complex programs, and




Neuroanatomical Correlates of Dreamwork

evaluation and correction of errors. Brain¬

via the retrograde pathway provided by

imaging studies have repeatedly found that

the inferior parietal lobule. This is ex¬

the prefrontal convexity is substantially

actly what Freud meant by topographical

deactivated during dreaming when the

regression—the most essential part of the

subcortical regions are highly active. Ac¬

process whereby dreams are formed. Be¬

cording to Yu (2003, 2007), these findings

cause of this topographical regressive pro¬

provide evidence for the mechanism of

cess, away from the motor system and

temporal regression that through dream¬

toward the perceptual system, dreamers do

ing, mental activity regresses developmen¬

not actually engage in motivated activity

tal^ from the experience-dependent adult

during sleep but imagine they are doing so.

cortex back to the instinctual and motiva¬

From an anatomical perspective, there

tional system of the brain that dominates

are probably multiple pathways for con¬

in infancy and childhood; mature logical

necting the subcortical motivational sys¬

reasoning and modes of thinking are tem¬

tem and the visual cortex. The inferior

porarily suspended in the service of illogi¬

mesial temporal lobe has been identified

cal, narcissistic, childish ones.

as one of the crucial pathways, in addi¬

The dorsolateral frontal cortex is one

tion to the supramarginal gyrus, for the

of the major divisions of the prefrontal

generation of dreams (Yu, 2001). The in-

convexity. Its primary function is to con¬

ferotemporal cortex has intense afferent

vert thoughts into action by programming

and efferent connections to both the visual

motor sequences. The inferior parietal lob¬

representation cortex and the subcortical

ule, and in particular the supramarginal

motivational system. It is well known that

gyrus, participates in the highest levels of

abnormal excitation of the temporal lobe

perceptual information processing, includ¬

alone during an epileptic attack or explor¬

ing symbolic operations. This function is

atory electrical stimulation during surgery

required for the conversion of concrete

can lead to experiential hallucinations and

perception into abstract thinking, and for

perceptual illusions that bear a resem¬

the retention of organized experience. The

blance to a dreaming state. The experien¬

dorsolateral frontal cortex is deactivated

tial hallucinations caused by excitations to

during dreaming, suggesting that the motor

the temporal cortex are often reported to

gateway from motives to actions is blocked

be unfamiliar, strange, and senseless, but

(see Yu [2003] for a review of neurolog¬

after exploration can be broken up into

ical evidence). By contrast, the posterior

shorter or longer sequences of earlier ex¬

brain plays an active part in dream forma¬

periences. This is similar to what Freud

tion (Yu, 2001, 2006), and lesions in the

referred to as condensation. The percep¬

supramarginal gyrus result in global ces¬

tual illusions triggered by the stimulation

sation of dreaming (Solms, 1997). Accord¬

of the temporal cortex involve a sudden

ingly, the focal point of mentation activity

change in the perceived appearance of an

shifts from the dorsolateral frontal region,

object or in the subjective feeling toward

the executive end of the motor system in

an object, including, for example, things

waking life, toward the perceptual system,

suddenly becoming familiar or appearing

Neuroanatomy of Dreams

to be strange, becoming larger or smaller, and coming closer or going farther away. From the Freudian perspective, any event of incoherent, accentuated, or diminished intensity occurring in dreams is ascribed to the effect of displacement. The inferior temporal cortex is function¬ ally specialized for object representations. This area of the brain is driven by complex¬ ity rather than specificity. The activation of the inferior temporal cortex provides rela¬ tively coarse and imprecise representations of visual objects. Additionally, the inferior


gyrus controversy (dream work). NeuroPsychoanalysis, 3, 47-59. Yu, C.K.-C. (2003). Neuroanatomical cor¬ relates of dreaming, III: The frontal-lobe controversy (dream censorship). NeuroPsychoanalysis, 5, 159-169. Yu, C.K.-C. (2006). Memory loss is not equal to loss of dream experience: A clinicoanatomical study of dreaming in patients with posterior brain lesions. NeuroPsychoanalysis, 8, 191-198. Yu, C.K.-C. (2007). Cessation of dreaming and ventromesial frontal-region infarcts. NeuroPsychoanalysis, 9, 85-92.

temporal cortex is centrally engaged in clas¬ sifying visual stimuli into certain behaviorally meaningful categories, and therefore,

Neuroanatomy of Dreams

forging connections between visual expe¬ riences, complex or sequential behavioral

Dreaming is a complex neurophysiologi¬

patterns, and temporal emotional experi¬

cal process that requires the correct state

ences. This capacity of the inferior tempo¬

and intact neuroanatomy. Although it can

ral cortex is essential for symbolism to take

emerge from any sleep stage, rapid eye

place. Therefore, as with condensation and

movement (REM) sleep is the most com¬

displacement, the dreamwork mechanism

mon stage for dreaming. Because the act

of symbolism most probably transpires in

of dreaming involves visual imagery, som-

the inferior temporal lobe. Taken together,

esthetic perception, memory, emotion, and

dreamwork or dream formation may not only

perhaps the subconscious mind, almost

be facilitated by the pervasive deactivation

any region of the brain may be involved.

of the dorsolateral prefrontal cortex but also

For these reasons, accurate assessment of

positively caused by the activation of the pos¬

the neuroanatomy of dreaming is challeng¬

terior brain and inferior temporal structures.

ing and best achieved by dividing the phe¬

Calvin Kai-Ching Yu

nomenon into two constituent parts; the neuroanatomy of REM sleep and the neu¬

References Freud, S. (1900). The interpretation of dreams. In J. Strachey (Ed. & Trans.), The standard edition of the complete works of Sigmund Freud (Vols. 4-5). London: Hogarth Press.

Solms, M. (1997). The neuropsychology of dreams: A clinico-anatomical study. Hills¬ dale, NJ: Erlbaum. Yu, C.K.-C. (2001). Neuroanatomical corre¬ lates of dreaming: The supramarginal

roanatomy of the dreaming process. REM sleep is an ultradian physiologi¬ cal state that occupies approximately 20 percent of a healthy adult’s night sleep and is characterized by REMs, muscle atonia, and a low-voltage, fast electro¬ encephalogram (EEG). REM-sleep epi¬ sodes become progressively longer as the sleep period progresses, with the longest




Neuroanatomy of Dreams

REM episodes occurring in the morning

dream researcher J. Allan Hobson (2002)

before arising. REM sleep is driven by

provided a first-person account of sleep

a mutually inhibitory flip-flop switch in

and dream loss and peduncular hallucinosis

the mesopontine tegmentum consisting of

following an acute ischemic lateral medul¬

REM-off (e.g., ventrolateral periaqueduc¬

lary cerebrovascular accident. Although

tal gray and lateral pontine tegmentum)

these and other cases have been reported,

and REM-on (e.g., sublaterodorsal nu¬

detailed neuroimaging, polysomnography,

cleus and precoeruleus) areas. Each area

and neuropsychological testing have been

contains y-aminobutyric acid (GABA-er-

lacking, throwing into question whether

gic) neurons that heavily innervate and

the neurological insult actually eliminated

inhibit the opposing area. The REM-on

dreaming, or just compromised the abil¬

area also contains glutaminergic neurons

ity to generate REM sleep or report dream

located in two areas, with one regulating

content (e.g., visual nonremembrance).

the REM EEG through projections to the

More recently Bischof and Bassetti re¬

basal forebrain, and the other regulating

ported the case of a 73-year-old female

REM atonia through projections to the

with acute total dream loss following bi¬

medulla and spinal cord (Lu et ah, 2006).

lateral posterior cerebral artery infarction.

Other important brain regions include the


pedunculopontine, laterodorsal tegmen¬

REM sleep, but dreams were not recalled,

tal, and extended ventrolateral preoptic

even following multiple awakenings from

nuclei, all of which inhibit REM-off neu¬

polysomnographically determined REM

rons, and the dorsal raphe, locus coeru-

sleep. Neuropsychological testing was un¬

leus, and orexin (hypocretin) producing

remarkable and primary sleep disorders

neurons, all of which excite REM-off neu¬

were absent. Detailed neuroimaging re¬

rons. The orexin (hypocretin) neurons sta¬

vealed infarction of the bilateral occipital

bilize the REM-sleep flip-flop switch and

lobes, including the visual cortices as well

prevent unwanted switching of the sleep/

as the right inferior lingual gyrus and right

wake state or intrusion of REM phenom¬

posterolateral thalamus (Bischof & Bas¬

enon (such as atonia during cataplexy, or

setti, 2004). This important case demon¬

dreams during hypnagogic hallucinations)

strates that dreaming and REM sleep are

into wakefulness (Lu et al., 2006).

dissociable states. REM sleep alone is not



Much has been learned regarding func¬

sufficient for the generation of dreaming,

tional human neuroanatomy by studying

but rather other processes, particularly

loss of function following neurological in¬

those emanating from the occipital lobes

sult. Cessation of dreaming following neu¬

and the inferior lingual gyrus (a brain re¬

rological damage was first observed by

gion involved with the processing of emo¬

Jean-Martin Charcot in 1883, followed by

tions and visual memories) appear to be

Hermann Wilbrand in 1887, resulting in the

crucial to the dreaming process.

term CWS (Charcot-Wilbrand syndrome)

In conclusion, dreaming is a complex

to describe this phenomenon (Charcot,

neurophysiological process

1883; Wilbrand, 1887). Recently, sleep and

sleep playing a crucial role. Although many



Neuroanatomy of REM Sleep and Depression


neuroanatomical regions have been impli¬

may stay in REM too long. Now NREM

cated, it appears that the occipital lobes,

sleep is affected in depression as well, and

and perhaps the inferior lingual gyrus, are

things get quite complex once you start ask¬

key components of the dreaming mecha¬

ing questions such as are the REM changes

nism. The complexities of dreaming make

characteristic of all forms of depression?

creation of an animal model to study the

(No) or do they occur in all demographic

phenomenon unrealistic. Therefore, future

groups? (No) and so forth. Nevertheless,

studies focusing on loss of function follow¬

there does seem to be a deep relationship

ing neurological insult are likely to provide

between REM sleep per se and depression.

the best insights into this fascinating phe¬

The definitive evidence for this comes

nomenon going forward.

from neuroanatomy and from the fact that

Nathaniel F. Watson

See also: entries related to Sleep and the Brain

REM deprivation temporarily reverses the depression, at least in most people with major depression. Most investigators sus¬


pect that the reason for the deep relation

Bischof, M., & Bassetti, C.L. (2004). Total dream loss: A distinct neuropsychological dysfunction after bilateral PCA stroke. An¬ nals of Neurology, 56(4), 583-586.

between REM and major depressive dis¬

Charcot, M. (1883). Un cas de suppression brusque et isole'e de la vision mentale des signes et des objets (formes et couleurs). Progressive Medicine, 2, 568-571.

order (MDD) may lie in the neuroanatomy of both states. So it is worth reviewing the neuroanatomy of REM sleep and of de¬ pression to see how they overlap and caus¬ ally interact. MDD (American Psychiatric Associa¬

Hobson, J. A. (2002). Sleep and dream suppres¬ sion following a lateral medullary infarct: A first-person account. Consciousness and Cognition, 11, 377-390.

tion, 2000) is associated with a range of

Lu, J., Sherman, D., et al. (2006). A putative flip-flop switch for control of REM sleep. Nature, 447(7093), 589-594.

ture a barrage of negative self-appraisals

Wilbrand, H. (1887). Ein Fall von Seelenblindheit und Hemianopsie mit Sectionsbefund. Dtsch Z Nervenheilkd, 2, 361-387.

symptom clusters, including the hallmark persistent sad, anxious, or empty feelings. Cognitive distortions of depression fea¬ that lead to feelings of hopelessness and/ or pessimism, guilt, worthlessness, and/ or thoughts of suicide, or even suicide at¬ tempts. Memory too is affected with neg¬ ative and painful memories favored in recall and in acquisition and consolida¬

Neuroanatomy of REM Sleep and Depression

tion processes. Dreams become intensely unpleasant experiences with elevated lev¬ els of what used to be called masochistic

One of the best-documented relationships

content or scenes of aggression by un¬

between mood disorders and sleep is the

known strangers against the dreamer/self.

relationship between depression and REM

Nightmares become more frequent occur¬

sleep. The basic finding is that depressed

rences in the dream life of the depressed

people go into REM too quickly and some





Neuroanatomy of REM Sleep and Depression

Although REM sleep has long been

assume that they operate in mutual inhibi¬

known to be altered in depression, its role in

tory balance with the dorsal system play¬

production of symptomology of depression

ing the leading role. Its job you might say

has never been adequately clarified (for re¬

is to regulate arousal levels in the ventral

views see Armitage, 2007; Nutt, Wilson, &

system. If the dorsal system is damaged or

Paterson, 2008; Tsuno, Besset, & Ritchie,

inhibited by any physiological dysfunction

2005). The repeatedly confirmed fact that

then the ventral system would be released

both selective REM and total sleep depri¬

from regulatory constraints and would ex¬

vation provides dramatic and immediate

hibit chronic overactivation.

(though temporary) relief for some people

Consistent with the regulatory role of the

with depression (Vogel, 1975) supports the

dorsal system over paralimbic and other

claim that REM does indeed play some role

preferontal circuits and functions; and con¬

in production of at least some depressive


symptoms in some people with MDD.

model of depression, resting-state PET




Mayberg (1997) presented a limbic-

and single-photon emission computed to¬

prefrontal interactional model of the neu¬

mography studies in patients with unipolar

roanatomy of depression that consists of

depression have most consistently found

three neurofunctional compartments that

decreased function in the dorsolateral pre¬

account for differing clusters of depressive

frontal (e.g., Mayberg, Lewis, Regenold, &

systems. Cognitive disturbances of depres¬

Wagner, 1994) and increased activation

sion are related to dysfunction in the dorsal

in ventral system structures (Liotta et al.,

compartment of the model, which includes

2000). Once the dorsal system is impaired,

the dorsolateral prefrontal cortex and dor¬

the systems it regulates are released from

sal anterior cingulate, and posterior cingu¬

top-down inhibitory control and you get in¬

late. Emotional, vegetative, and somatic

creases in activation of ventral system struc¬

symptoms of depression (affect sleep and

tures in depressed patients. Such increases

appetite) are associated with disturbances

in activity in depressed patients have been

of the ventral compartment, which consists

documented via rCMRglc (regional cere¬

of orbitofrontal, paralimbic cortical, sub¬

bral metabolic glucose) and rCBF (regional

cortical, and brainstem regions. The rostral

cerebral blood flow) studies in ventrolat¬

compartment (the rostral anterior cingulate

eral, ventromedial, and orbitofrontal cortex

cortex, corresponding to Brodmann area

and subgenual prefrontal cortex, amygdala,

24a) has connections to both the dorsal

and insular cortex (Liotta et ah, 2000).

and ventral compartments and may serve

Consistent with an etiological role of

an important regulatory role in the overall

these overactivated brain systems in pro¬

network. I will focus here on interactions


between the dorsal and ventral components

pretreatment abnormalities found in pre¬

of the model as these seem most relevant

frontal, and limbic-paralimbic areas in de¬

to sleep in depression.

pressed patients appear to normalize with

To understand interactions of dorsal ver¬ sus ventral components in sleep we have to




recovery from depression (Drevets et ah,


Neuroanatomy of REM Sleep and Depression


Now we know from neuroimaging stud¬

Thus, attention to the overlap of the neu¬

ies of REM sleep in healthy people that

roanatomy of REM sleep and of depres¬

REM is associated with downregulation

sion yields insights into treatment options.

of the dorsal system and upregulation of

What remains unanswered, however, is

the ventral system during each episode of

why REM sleep would reproduce the anat¬

REM. REM normally activates the ventral

omy of depression in the first place? Why

system and deactivates the dorsal system

would Mother Nature create a physiologi¬

in healthy people, thus reproducing the de¬

cal system that each night periodically ac¬

pressive state. Brain-activation patterns in

tivates the ventral system and activates it

REM demonstrate high activation levels

in such a way as to enhance negative affect

in limbic/amygdaloid sites and portions of

(after all, most dreams contain significant

medial prefrontal cortex but hypoactiva-

amounts of negative affect)?

tion of dorsolateral prefrontal cortex sites

(Pace-Schott, 2005). Thus, it appears that each REM episode is associated with a re¬

Patrick McNamara

See also: entries related to Sleep and the Brain

production of key aspects of the neuroanat¬


omy of depression, and it is therefore not

American Psychiatric Association.


unreasonable to ask if REM can negatively

Diagnostic and statistical manual of men¬

impact dorsal and ventral systems in such a

tal disorders (4th ed.). Washington, DC:

way as to be depressogenic.


If it is true that REM reproduces the neu¬ roanatomy of depression during each REM episode then how does that manifest in people with depression to begin with? We would predict that REM measures would be enhanced in people with depression; that is, if we could dampen down or suppress those REM phenomena, the depression would be relieved. It is well known that cer¬ tain REM-sleep indices are enhanced in de¬ pression. Reduced REM-sleep latency and increased REM density and REM time are commonly observed in depressed patients (Tsuno et al., 2005). REM-sleep depriva¬ tion can temporarily alleviate depressive symptoms (Vogel, Thurmond, Gibbons, Sloan, & Walker, 1975). Most antidepres¬ sant drugs suppress some aspect of REM sleep and degfee of REM suppression is correlated with degree of symptomatic re¬ lief in responders (Vogel et al., 1975).

Armitage, R. (2007). Sleep and circadian rhythms in mood disorders. Acta Psychiatrica Scandinavica, 115(S433), 104-115. Drevets, W.C., Price, J.L., Bardgett, M.E., Reich, T., Todd, R. D., & Raichle, M.E. (2002). Glucose metabolism in the amyg¬ dala in depression: Relationship to diag¬ nostic subtype and plasma cortisol levels. Pharmacology Biology & Behavior,


431-447. Liotta, M., Mayberg, H. S., Brannan, S. K., Mc¬ Ginnis, S., Jerabek, P., & Fox, P.T. (2000). Differentials corticolimbic correlates of sadness and anxiety in healthy subjects: Im¬ plications for affective disorders. Biological Psychiatry, 48, 30-42. Mayberg, H. S. (1997). Limbic-cortical dysregulation: A proposed model of depression. Journal of Neuropsychiatry and Clinical Neurosciences, 9, 471—481.

Mayberg, H. S., Lewis, P.J., Regenold, W., & Wagner, H.N. (1994). Paralimbic hypoper¬ fusion in unipolar depression. Journal of Nuclear Medicine, 35, 929-934.




Neurobiology of Psychoanalysis in Wake and REM Sleep

Nutt, D.J., Wilson, S.J., & Paterson, L.M. (2008). Sleep disorders as core symptoms of depression. Dialogues in Clinical Neuro¬ science, 10(3), 329-335.

the efficiency of censorship is decreased,

Pace-Schott, E.F. (2005). The neurobiology of dreaming. In M. H. Kryger, T. Roth, & W. C. Dement (Eds.), Principles and prac¬ tice of sleep medicine (4th ed., pp. 551— 572). Philadelphia: Elsevier.


Tsuno, N., Besset, A., & Ritchie, K. (2005). Sleep and depression. Journal of Clinical Psychiatry, 66, 1254-1269.

ple would give way to the primary process

Vogel, G. W. (1975). A review of REM sleep deprivation. Archives of General Psychia¬ try, 32, 749-761.

of unconscious wishes. Today, several experimental psychology

Vogel, G.W., Thurmond, A., Gibbons, P., Sloan, K„ & Walker, M. (1975). REM sleep reduction effects on depression syn¬ dromes. Archives of General Psychiatry, 32, 765-777.

allowing latent thought content to enter the dreamer’s consciousness under the figu¬ rative form of manifest content, produced dreamwork involving condensation

and displacement. When this happens, the elaborated processes that regulate wakingmind function and follow the reality princi¬ which follows the pleasure principle, lead¬ ing to disguised phantasmatic satisfaction

studies have confirmed that there are indeed active processes that suppress (repress) un¬ wanted memories from entering conscious¬ ness during waking, with neuroimaging studies even suggesting the primary in¬ volvement of the prefrontal cortex in their generation. Indeed, the more this brain level

Neurobiology of Psychoanalysis in Wake and REM Sleep

is activated—as memory-controlling struc¬ tures (hippocampus) are deactivated—the more effective the repression of memories is. This repression ability is favored by sleep

Sigmund Freud (1917) wrote that “we must

and decreases with advancing age.

recollect that all of our provisional ideas

In contrast, it is difficult to find any

in psychology will presumably one day be

neurobiological support for an organized

based on an organic substructure.” To what

dreamwork that would produce mean¬

extent has his prediction been confirmed?

ingful symbolic content during the REM

Freud’s basic theory was that a form of

dreaming sleep stage, since dream menta¬

unconscious censorship blocks access to

tion only shows psychotic-like properties.

consciousness of memories, drives, wishes,

Indeed, electroencephalographic studies of

and feelings because they would induce

gamma rhythm and central responsiveness

behavioral disturbances (anxiety) due to

(evoked potential findings) clearly show

their emotional or ethical unacceptabil¬

disconnections between forebrain struc¬

ity. However, the intrusion of such uncon¬

tures, as is seen in schizophrenia, and also

scious events can be incidentally observed

show disinhibitory processes, which is an

through parapraxes (slips of the tongue, of

index of deficits in central control processes.

the pen, forgetting, misreading, mislaying).

Neuroimaging results also mainly indicate

Further, during dreaming, as developed in

deactivation of the dorsolateral prefrontal

his The Interpretation of Dreams (1900),

cortex, which is activated during waking,

Neurobiology of Psychoanalysis in Wake and REM Sleep


emphasizing the loss of brain-control pro¬

disturbed brain. First, cortisol, which in¬

cesses during REM sleep. Moreover, it has

hibits memorization, is released by the su-

long been established by pharmacological

prarenals in the early morning. Also, in the

research that dopamine receptor blockers,

seconds preceding behavioral arousal, wak¬

which suppress psychotic symptoms, tend

ing function reappears in the brain with the

to decrease dreaming; also, new neurolep¬

release of noradrenaline; this could favor a

tics used in the treatment of schizophrenia

break with previously present psychologi¬

increase noradrenergic and serotonergic

cal processes. Recent research has also in¬

function, and both of these neuromodula¬

dicated that endogenous increases in Ca2+/

tors are nearly entirely absent during REM

calmodulin-dependent protein kinases II

sleep. Finally, neurochemical results have

(CaMKII) upon arousal, or a transient de¬

shown that dopamine levels are reduced

crease in the sensitivity of (3-noradrenergic

in the prefrontal cortex during REM sleep

receptors could explain the nonrecording

while glutamate levels remain unchanged,

of dreams in the waking memory. Finally,

in both cases similar to what is observed

it has been established that the specific

in schizophrenia. Further, there is a maxi¬

dorsolateral prefrontal cortex, which is

mal release of dopamine and a decrease in

involved in memory processes, recovers

glutamate in the nucleus accumbens during

its waking properties with a longer delay

REM sleep, again as is seen in schizophre¬

than do all other forebrain structures. This

nia. These results underline the conclusion

could also contribute to the obliteration of

that increases in central dopamine and de¬


creases in glutamate induce both psychotic symptoms and vivid dreaming.

Consequently, today’s neurobiological knowledge tends to support the psychoana¬

In view of the previous results, it is im¬

lytic theory of unconscious processes with

probable that, in the context of such disor¬

respect to the repression of access of men¬

ganized brain function and in the presence

tal content to the waking consciousness.

of such psychological abnormalities, there

In contrast, because of the major distur¬

is an organized censorship that acts during

bances that occur in brain function during

REM sleep to modify mental content and

REM sleep, sooner or later in dreams there

make it acceptable to an unconscious.

is usually a disintegration, a loss of coher¬

Finally, another significant assertion of

ence, an appearance of a psychotic-like

Freud now encounters difficulties in view

kind of mentation that is incompatible with

of modern neurobiological knowledge:

Freud’s postulated lucid yet unconscious

“The forgetting of dreams remains inexpli¬

censorship that would transform unaccept¬

cable unless the power of the psychical cen¬

able mental content to render it acceptable.

sorship is taken into account.” It has been

Finally, with respect to dream recall, there

established that there is, generally, evanes¬

is often some rebuilding of content upon

cence of dreams upon awakening. However,

arousal (Gottesmann, 2010).

several knowjn physiological processes are

Claude Gottesmann

better able than Freud’s theory to explain this forgetting in such a neurobiologically

See also: entries related to Sleep and the Brain




Neurofeedback for Sleep Problems


brain activity, which is associated with

Freud, S. (1900). The interpretation of dreams. London: The Hogart Press.

various disorders such as epilepsy, at¬

Freud, S. (1917). The history of the psychoana¬ lytic movement (Trans. A. A. Brill). In Ner¬

sleep disorders. Unfortunately, much of the previous

vous and mental disease monograph series,

research concerning neurofeedback has

no. 25. (Original work published 1914.) Gottesmann, C. (2010). To what extent do neurobiological sleep-waking processes sup¬ port psychoanalysis. International Review of Neurobiology, 92, 233-290.

tention deficit hyperactivity disorder, or

suffered from a lack of standardized mea¬ sures of target symptoms, neglected the assessment of actual training-related EEG changes, and conducted studies with in¬ appropriate control groups or insufficient sample sizes. Additional, well-controlled

Neurofeedback for Sleep Problems

empirical studies are thus recommended before neurofeedback can be considered a reliable nonpharmacological treatment.

Neurofeedback is a sophisticated type of

Concerning sleep and sleep problems we

biofeedback, which basically refers to

recently focused our research on the sen¬

an operant-conditioning paradigm. Par¬

sorimotor cortex, which shows a very dis¬

ticipants are instructed to learn to self

tinct oscillatory pattern in a frequency

regulate distinct parameters of their cor¬

range between 12 and 15 Elz, also termed

tical activity as assessed by the means of

sensorimotor rhythm (SMR). SMR ap¬

electroencephalography (EEG). The aim

pears to (1) be dominant during quiet but

of neurofeedback is to teach individuals

alert wakefulness, and (2) synchronizes by

what specific states of cortical arousal

the inhibition of motor behavior. Further¬

feel like and how to activate such states

more, this frequency range is known to be

voluntarily. During neurofeedback EEG

abundant during light nonrapid eye move¬

is recorded and the relevant components

ment (NREM) sleep, and is overlapping

are extracted and fed back to the individ¬

with the sleep spindle frequency band.

ual using an online feedback loop (audio,

Sterman, Elowe, and MacDonald (1970)

visual, or audiovisual). The individual’s

were the first to demonstrate that operant

task may then be to increase/decrease the

conditioning of SMR during wakefulness

respective cortical parameter. When the

can influence subsequent sleep. Hauri and

correct EEG pattern is produced, the sub¬

colleagues (1981) then applied neurofeed¬

ject receives a positive response or reward

back of various EEG parameters to disor¬

by the computer. There is a growing body

dered sleep. These early results revealed

of evidence (for review, see Hoedlmoser,

that patients benefit from that kind of

Dang-Vu Thien, Desseilles, & Schabus,

SMR training; then, surprisingly, research

2010) suggesting that it is feasible to learn

on that topic faded away. Currently we in¬

to regulate specific brain oscillations by

tend to clarify the nature of these effects

neurofeedback. Thereby it becomes possi¬

in healthy controls as well as insomnia patients.

ble to directly counteract the maladaptive

Neuropsychology of Lost Dream Recall

In the first study (Hoedlmoser et al., 2008) healthy subjects who were randomly

conditioning of EEG can directly target clinically altered brain activity.

assigned to either a SMR-conditioning protocol or to a randomized-frequencyconditioning protocol were studied. Re¬


Kerstin Hoedlmoser See also: entries related to Dreams and Therapy

sults confirmed the increase of 12 to 15 Hz


activity over the course of 10 training ses¬

Hauri, P. (1981). Treating psychophysiologic insomnia with biofeedback. Archives of General Psychiatry, 38, 752-758.

sions in the experimental group. Interest¬ ingly, the increased SMR activity (1) was also expressed during subsequent sleep by eliciting positive changes in various sleep parameters such as sleep spindle number or sleep onset latency and (2) was associ¬ ated with the enhancement of declarative memory performance. As these fascinating results pointed to the possibility that peo¬ ple suffering from insomnia could likewise benefit from these protocols, we conducted a second study with subjects suffering from primary insomnia. Results indicate an increase of 12 to 15 Hz activity over the course of 10 SMR neurofeedback sessions. Furthermore, the change in SMR activity tends to be correlated with a reduction in

Hoedlmoser, K., Dang-Vu Thien, T., Desseilles, M., & Schabus, M. (2010). Nonpharmacological alternatives for the treatment of insomnia. In Y.E. Soriento (Ed.), Melatonin, sleep and insomnia (pp. 69-101). New York: Nova Science Publishers. Hoedlmoser, K., Pecherstorfer, T., Gruber, G., Anderer, P., Doppelmayr, M., Klimesch, W., & Schabus, M. (2008). Instrumental conditioning of human sensorimotor rhythm (12-15 Hz) and its impact on sleep as well as declarative learning. Sleep, 31, 1401-1408. Sterman, M.B., Howe, R.C., & MacDonald, L.R. (1970). Facilitation of spindle-burst sleep by conditioning of electroencephalographic activity while awake. Science, 167, 1146-1148.

the number of awakenings from pre- to post-SMR training. Interestingly, subjec¬ tive sleep quality was also enhanced over the course of neurofeedback and further¬

Neuropsychology of Lost Dream Recall

more sleep onset latency was tendentiously reduced after SMR but not after random¬

There are two core issues in the neuro¬

ized training. Last but not least slow sleep

psychology of dream recall, and they are

spindles during deep NREM sleep were

linked. The first is that dreams are noto¬

found to be exclusively enhanced after

riously difficult to remember. The second

SMR training. In summarizing, results

is that some people recall no dreams upon

indicate that healthy individuals as well

waking and claim on this basis that they do

as people suffering from primary insom¬

not dream at all. Among the latter group

nia can experience subjective as well as

particular interest attaches to those who

objective benefits from SMR condition¬

claim to have lost the ability to dream fol¬

ing. Further refining and empirically as¬

lowing focal brain damage. This is because

sessing respective protocols for clinical

the site of the damage could identify parts

use appears worthwhile as instrumental

of the brain that are pivotal for dreaming.




Neuropsychology of Lost Dream Recall

This in turn may yield new insights into the

undermines dreaming; this does not provide

function of dreams.

much insight into the function of dreams. It

The first systematic study of this (Solms,

merely confirms that they are a primarily

1997) revealed two significant facts. The

visual form of hallucination. The situation

first was that reported cessation of dream¬

is different when it comes to ventromesial

ing was indeed associated with damage to

frontal white matter. Recent research has

a specific part of the brain (in fact to two

narrowed the focus to the dopaminergic

specific parts of the brain). The second was

part of the ventromesial frontal white mat¬

that it was not associated with damage to

ter (Dahan et al., 2007; Lena et al., 2005;

the part of the brain that generates REM

Solms, 2001)—which is implicated in ap¬

sleep—which had hitherto been assumed

petitive reward-seeking behavior (Pank-

to also generate dreams. Surprisingly, no¬

sepp, 1998). This suggests that dreams are

body had ever determined whether damage

generated by (or) responses to instinctual

to the cholinergic pontine brainstem causes

urges (Solms, 2011). This has major theo¬

loss of dreaming. This is a minimum re¬

retical significance (cf. Lreud, 1900).

quirement for any structural-functional

Unsurprisingly, these conclusions led

correlation in neuropsychology: if a par¬

many commentators (e.g., Hobson & Pace-

ticular structure performs a particular func¬

Schott, 1999) to question their method¬

tion then loss of the first must cause loss of

ological basis. How do we know whether

the second. If not, then the structure does

patients who report loss of dreaming fol¬

not perform the function at issue. Solms

lowing brain damage are really not dream¬

(1997, 2000) therefore concluded that

ing; is it not possible that they are merely

dreams are not generated in the pontine

forgetting their dreams? This brings us


back to the unreliability of dream recall,

Loss of dreaming turned out to be as¬ sociated with damage in higher structures:

which is presumably exacerbated by brain damage.

(1) ventromesial frontal lobe white matter

This challenge can be met in three ways,

and (2) occipito-temporal cortex. (Solms

first, the memory functions of dreaming

initially thought the critical region was

and nondreaming patients with similar le¬

the so-called overlap zone between oc¬

sions can be compared. In doing so, Solms

cipital, temporal, and parietal cortex but

(1997) found differences in visual short

subsequent research narrowed the focus

term but not visual or verbal long-term

to Brodmann areas 19 and 37 [Bischof &

memory. This confirms the conclusion

Bassetti, 2004; Poza & Marti Masso, 2006;

reached previously: dreaming is contin¬

Yu, 2001].) What are the functions of these

gent on intact visual working memory. The

two parts of the brain and what do they re¬

fact that long-term memory is completely

veal about dreaming? The occipito-tempo¬

preserved in nondreaming patients, how¬

ral region is implicated in visual short-term

ever, suggests that these patients would

memory and therefore in the capacity to

encode new long-term memories of dream

generate visuospatial mental imagery. It

episodes if they occurred. A second ap¬

is not surprising that loss of this capacity

proach is to examine the dream-recall

Neuropsychology of Lost Dream Recall

capacities of patients with confirmed in¬ ability to encode episodic memories. This has not been systematically investigated but anecdotal reports exist, which con¬ firm that densely amnesic patients—such as the famous case of HM (S. Corkin, per¬ sonal communication, 2009)—do indeed report dreams immediately upon awaken¬ ing from REM sleep. This is because vi¬ sual working memory is preserved in such patients (Moscovitch et al., 2005). A third approach is to subject nondreaming pa¬


Hobson, J.A., & Pace-Schott, E. (1999) Re¬ sponse to commentaries. Neuropsychoanal¬ ysis, 1, 206-224. Lena, I., Parrot, S., Deschaux, O., MuffatJoly, S., Sauvinet, V., Renaud, B., et al. (2005). Variations in extracellular levels of dopamine, noradrenaline, glutamate, and aspartate across the sleep—wake cycle in the medial prefrontal cortex and nucleus accumbens of freely moving rats. Journal of Neuroscience Research, 81(6), 891-899. Michel, F., & Sieroff, E. (1981). Une approche anatomo-clinique des deficits de l’imagerie oneirique, est-elle possible? In Sleep: Pro¬

tients to REM awakening, thereby ensur¬

ceedings of an international colloquium.

ing maximal temporal proximity to dream

Milan: Carlo Erba Formitala.

episodes. All such studies to date of non¬ dreaming neurological patients confirm the absence of dream reports upon REM awak¬ ening (Bischof & Bassetti, 2004; Michel & Sieroff, 1981; Poza & Marti Masso, 2006; Schanfald, Pearlman, & Greenberg, 1985). In short, notwithstanding the method¬ ological challenges of all dream research, the available evidence strongly supports the view that acquired loss of dreaming (so-called Charcot-Wilbrand syndrome) does indeed occur. Mark Solms

References Bischof, M., & Bassetti, C.L. (2004). Total dream loss: A distinct neuropsychological dysfunction after bilateral PCA stroke. An¬ nals of Neurology, 56, 583-586. Dahan, L., Astier, B., Vautrelle, N., Urbain, N., Kocsis, B., & Chouvet, G. (2007). Promi¬ nent burst firing of dopaminergic neurons in the ventral tegmental area during para¬ doxical sleep. Neuropsychopharmacology, 32, 1232-1241.

Freud, S. (100/2001). The interpretation of dreams. Empire Books, NY.

Moscovitch, M., Rosenbaum, R., Gilboa, A., Addis, D., Westmacott, R., Grady, C., . . . Nadel, L. (2005). Functional neuroanatomy of remote episodic, semantic and spatial mem017: A unified account based on multiple trace theory. Journal of Anatomy, 207, 35-66. Panksepp, J. (1998). Affective neuroscience: The foundations of human and animal emo¬ tions. New York: Oxford University Press.

Poza, J., & Marti Masso, J. (2006). Total dream loss secondary to left temporo-occipital brain injury. Neurologia, 21, 152-154. Schanfald, D., Pearlman, C., & Greenberg, R. (1985). The capacity of stroke patients to re¬ port dreams. Cortex, 21, 237-247. Solms, M. (1997). The neuropsychology of dreams: A clinico-anatomical study. Mahwah, NJ: Erlbaum. Solms, M. (2000). Dreaming and REM sleep are controlled by different brain mechanisms. Behavioral and Brain Sciences, 23, 843-850. Solms, M. (2001). The neurochemistry of dreaming: Cholinergic and dopaminergic hypotheses. In E. Perry, H. Ashton, & A. Young (Eds.), The neurochemistry of con¬ sciousness (pp. 123-131). John Benjamin’s Publishing Co. Solms, M. (2011). Neurobiology and the neuro¬ logical basis of dreaming. In P. Montagna & S. Chokroverty (Eds.), Handbook of clinical




Nightly Sleep Duration and Mortality: The Story of a U-Shaped Relationship

neurology, 98: Sleep disorders—Part 1 (3rd

from 16 studies, Cappuccio et al. (2010)

series, pp. 519-544). New York: Elsevier.

estimated that long sleepers, generally de¬

Yu, C. (2001). Neuroanatomical correlates of dreaming: The supramarginal gyrus contro¬ versy (dream work). Neuropsychoanalysis, 30, 47-59.

fined as individuals reporting nine or more hours of sleep per night, were 30 percent more likely to die than normal sleepers. This increased risk associated with long sleep appears to be stronger among older compared to younger individuals (46% vs.

Nightly Sleep Duration and Mortality: The Story of a U-Shaped Relationship

22% increase in the risk of mortality), but does not differ by sex. There is also some evidence to suggest a stronger relationship between long sleep and mortality among

Shorter nightly sleep duration is a hallmark

studies conducted in East Asia compared to

of modem Western society, thought to be

studies conducted in Europe and the United

due, in part, to longer work schedules and

States (48% vs. 25% increase in the risk

a greater allotment of time to leisure ac¬

of mortality). Cappuccio et al. (2010) hy¬

tivities such as television and the Internet.

pothesized that this may be due to a lon¬

This trend is troublesome, as, overwhelm¬

ger life expectancy in Asian countries such

ingly, the epidemiological evidence indi¬

as Japan and that, in general, the studies

cates that short sleep is related to a higher

conducted in Asia were composed of older

risk of overall, as well as cardiovascular,


mortality (Cappuccio, D’Elia, Strazzullo,

Despite the consistency of the relation¬

& Miller, 2010; Gallicchio & Kalesan,

ships between sleep duration and mortal¬

2009). In a meta-analysis of 25 cohorts

ity, there is some debate in the literature

from 15 studies, Cappuccio et al. (2010)

as to whether the increases in mortality

showed that short sleepers, defined gen¬

risk associated with both short and long

erally as individuals reporting less than

sleep are real or whether they are due to

seven hours per night, had a statistically

other (confounding) variables (Cappuccio

significant 12 percent increased risk of

et al., 2010; Gallicchio & Kalesan, 2009).

death compared to normal sleepers (gen¬

Numerous factors are related to both sleep

erally defined as those sleeping seven to

duration and mortality that could serve as

eight hours per night). This increase in risk

potential confounders, including age, ed¬

associated with short sleep appears to be

ucation, marital status, health behaviors

consistent among men and women, across

(e.g., smoking), and the presence of health

age groups, and by country (Cappuccio

conditions such as hypertension and de¬

et al., 2010).

pression (Grandner, Hale, Moore, & Patel,

Similarly, the epidemiological literature

2010). While most of the epidemiological

indicates that longer sleep duration is also

literature examining sleep duration and

related to an increased risk of death (Cap¬

mortality from which the Cappuccio et al.

puccio et al., 2010; Gallicchio & Kale¬

(2010) results were derived took into ac¬

san, 2009). Based on data from 27 cohorts

count these potential confounding factors,

Nightmare Content in Adults


there remains the potential for bias due

short sleep duration is a true risk factor for

to unmeasured confounding (i.e., other

mortality, with the increasing number of

important confounding factors that have

individuals reporting shorter sleep times,

not been identified or were not measured

such an intervention would have a large

or considered in the analyses) or residual

public health impact. Research in this area

confounding by factors that have been in¬

is needed, as well as in the area of mecha¬

cluded in the published studies.

nisms by which shorter and longer sleep

Yet, despite the debate, the results re¬

may lead to an increased risk of death.

ported in the epidemiological literature are

Lisa Gallicchio

generally consistent, suggesting that the as¬ sociations are real. However, the specific mechanisms underlying the associations

See also: entries related to Sleep and Develop¬ ment; entries related to Sleep Disorders

between sleep duration and mortality are


poorly understood. Short-term forced sleep

Cappuccio, F. P., D’Elia, L., Strazzullo, P., & Miller, M. A. (2010). Sleep duration and all¬ cause mortality: A systematic review and meta-analysis of prospective studies. Sleep, 33, 585-592.

deprivation has been shown in experimen¬ tal studies to cause adverse endocrinologic, immunologic, and metabolic effects (Spie¬ gel, Leproult, & Van Cauter, 2005), but it is unknown whether these studies are ap¬ plicable to chronic sleep deprivation. Inter¬ estingly, it may be that short sleep elevates stress levels, leading to disease, neuronal damage, and earlier aging (Grandner et al., 2010). Even less is known about potential mechanisms underlying the association be¬ tween long sleep and mortality. Among the postulated mechanisms are an increased amount of sleep fragmentation among long sleepers compared to normal sleepers, ad¬ verse changes in cytokine levels associated

Gallicchio, L., & Kalesan, B. (2009). Sleep duration and mortality: A systematic re¬ view and meta-analysis. Journal of Sleep Research, 18, 148-158. Grandner, M.A., & Drummond, S.P. (2007). Who are the long sleepers? Towards an un¬ derstanding of the mortality relationship. Sleep Medicine Reviews, 11, 341-360. Grandner, M. A., Hale, L., Moore, M., & Patel, N. P. (2010). Mortality associated with short sleep duration: The evidence, the possible mechanisms, and the future. Sleep Medicine Reviews, 14, 191-203.

cal challenge such that long sleepers are

Spiegel, K., Leproult, R., & Van Cauter, E. (2005). Metabolic and endocrine changes. In C. Kushida (Ed.), Sleep deprivation:

not exposed to potentially beneficial mild

Basic science, physiology, and behavior

with long sleep, and lack of physiologi¬

stressors (Grandner & Drummond, 2007).

(pp. 293-317). New York: Marcel Dekker.

The state of the research on sleep dura¬ tion indicates that sleep duration is a risk marker for mortality; it is yet unknown as

Nightmare Content in Adults

to whether interventions aimed at modify¬ ing sleep behaviors would serve to decrease

Nightmares are defined as disturbing men¬

morbidity and overall mortality in the gen¬

tal experiences that generally occur during

eral population. Indeed, if, in particular,

REM sleep and often result in awakening




Nightmare Content in Adults

(ICSD-2 [Internationa] Classification of

(13%), sinister presence (13%), being

Sleep Disorders-2]). Whereas nightmare

late (5%), suffocation (3%), hallucinated

frequency in different populations have

creatures (3%), and being paralyzed (3%).

been studied extensively—see, for ex¬

The most detailed study was carried out

ample, the meta-analysis by Schredl and

by Zadra, Duval, Begin, and Pilon (2004)

Reinhard (2011), research regarding night¬

analyzing 125 nightmares reported by 125

mare content is rather scarce, especially in

women (mean age: 32 years) who kept a


dream diary, one dream per participant.

Garfield (1984) analyzed 158 nightmares

The thematic analyses yielded the follow¬

in children, who reported that the most com¬

ing distribution of nightmare topics: phys¬

mon themes were: being chased (49%), sens¬

ical aggression (26%), ominous mood

ing something scary (18%), injury/death

(12%), failure/helplessness (10%), inter¬

(17%), losing something (5%), and fall¬

personal conflicts (9%), and being ignored

ing (3%). In another content analytic study

or rejected (6%). Other themes occurring 5

(N - 381 dreams), Schredl and Pallmer

percent or less included being chased but

(1998) obtained comparable results: being

not caught, presence of demons, frighten¬

chased (42%), sensing something scary

ing insects or spiders, health problems or

(20%), deaths/injuries of significant oth¬

concerns, being stuck or trapped, and ac¬

ers (20%), and falling (11%). Other topics

cidents. The present study investigated

such as examinations (3%), natural disas¬

nightmare frequency and the frequency of

ters (4%), or war (5%) occurred less often.

various topics in them. The five most com¬

For adults, three studies (Dunn & Bar¬

mon nightmare topics in a representative

rett, 1988;Hearne, 1991; Kales etal., 1980)

German sample (N = 1,022) were falling,

elicited nightmare content in small clini¬

being chased, paralyzed, being late, and the

cal samples (sample sizes varied from 30

deaths of close persons (Schredl, 2010).

to 38, the mean ages of the samples were

Summarizing the results while keep¬

about 35 years). The four most prominent

ing in mind that the methodological ap¬

themes in the Kales et al. (1980) study

proaches and samples have been very

were fear of attack (73%), fear of falling

different, the main topics seem to be being

(73%), fear of death (60%), and choking/

chased, injury/death of others, falling, and

suffocation (30%). The nightmare topics

witnessing violence. Even though several

in the sample of Dunn and Barrett (1988)

topics can be explained by the continuity

were distributed as follows: being chased

hypothesis of dreaming (e.g., the higher

(72%), deaths of family/friends (64%),

occurrence of examination dreams in per¬

falling (53%), own death (39%), threaten¬

sons with high educational levels; Schredl,

ing animals/monsters (33%), and violent

2010), further research is needed to inves¬

destruction scenes such as war and natural

tigate the possibly metaphoric relationship

disasters (24%). The nightmare sufferers

between nightmare topics such as falling

in the Heame (1991) study reported other

or being chased and waking-life stressors.

themes to be most prominent in their night¬

Michael Schredl

mares: witnessing horror/violence (32%), experiencing attack/danger (29%), flight

See also: entries related to Dream Content




distress or impairment. A DSM-IV (Di¬

Dunn, K. K., & Barrett, D. (1988). Character¬ istics of nightmare subjects and their night¬ mares. Psychiatric Journal of the University of Ottawa, 13, 91-93.

agnostic and Statistical Manual of Men¬

Garfield, P.L. (1984). Your child’s dreams. New York: Ballentine. Hearne, K.M.T. (1991). A questionnaire and personality study of nightmare sufferers. Journal of Mental Imagery, 15(3-4), 55-64. Kales, A., Soldatos, C.R., Caldwell, A., Charney, D., Kales, J. D., Markel, D., et al. (1980). Nightmares: Clinical characteristics and personality pattern. American Journal of Psychiatry, 137, 1197-1201. Schredl, M. (2010). Nightmare frequency and nightmare topics in a representative German sample. European Archives of Psychiatry and Clinical Neuroscience, 260, 565-570. Schredl, M., & Pallmer, R. (1998). Geschlechtsunterschiede in Angsttraumen von Schiilerlnnen. Praxis der Kinderpsychologie und Kinderpsychiatrie, 47, 463^476. Schredl, M., & Reinhard, I. (2011). Gender differences in nightmare frequency: A meta-analysis. Sleep Medicine Reviews, 15, 115-121. Zadra, A., Duval, M„ Begin, E., & Pilon, M. (2004). Content analysis of nightmares. Sleep Supplement, 27, A64.

tal Disorders-IV) diagnosis of nightmare disorder is made when the frequency and

severity of nightmares result in significant distress or impairment—usually consid¬ ered to be at least one such nightmare per week. Although nightmares may occur in the course of a general medical condition or as a result of using, abusing, or with¬ drawing from medications or other drugs, the DSM-IV considers them in such cases to be only secondary to a nightmare dis¬ order diagnosis, and a diagnosis of night¬ mares due to a general medical condition

or substance-induced nightmare disorder would be applied instead. Nightmares may also occur in the course of several other mental disorders such as generalized anxiety disorder, social anxi¬ ety disorder, panic disorder, schizophre¬ nia, mood disorders, adjustment disorders,

and personality disorders. And they fre¬ quently occur in the course of normal and atypical bereavement during which grief figures as the predominant dysphoric dream emotion; these may form a distinct subtype of dreams (Kuiken, Lee, Eng, & Singh, 2006). It is important to distinguish


nightmare disorder from posttraumatic

nightmares, which are more severe, more Nightmares are repeated occurrences of

disturbing, and often, but not necessar¬

dreams that are extremely dysphoric, ex¬

ily, associated with acute stress disorder

tended in time and well remembered upon

or posttraumatic stress disorder (PTSD).

awakening; they usually involve active

Both nightmare disorder and PTSD night¬

efforts to avoid apparent threats to one’s

mares are distinguished from sleep terrors,

survival, security, or physical integrity.

which also involve fear-based arousals

Nightmare episodes generally occur dur¬

but which typically arise from non-REM

ing the second half of the sleep period. On

sleep, are not accompanied by such vivid

waking up, the nightmare experience, or the

and elaborate dreams, and do not result in

sleep disturbance that it produces, usually

awakenings from which recall of the expe¬

leads to a degree of clinically significant

rience is as clear and detailed.





Nightmares typically occur in a lengthy

ranging from approximately 2:1 to 4:1.

and elaborate dream sequences that seem

The gender difference continues in adult¬

real while they occur and cause anxiety,

hood even though nightmare prevalence

fear, terror, or some other dysphoric emo¬

decreases steadily with age for both sexes.

tion such as anger or disgust. The content

Among adults, prevalence is 2 to 5 percent

of the nightmares usually focuses on the

for nightmares often or always and 8 to 30

individual’s attempts to avoid or cope with

percent for nightmares one or more per

imminent physical danger such as being

month. Prevalence for adult/elderly sam¬

pursued, attacked, or injured, but it may

ples is only 1 to 2 percent for nightmares

also involve themes that evoke anger, re¬

often or always. Twin studies have identified genetic ef¬

vulsion, and other negative emotions. Because dreaming is usually longer

fects on the disposition to nightmares and

and more intense in the second half of the

on the co-occurrence of nightmares and

night, nightmares are also more likely to

other parasomnias such as somniloquy.

occur later in the night. However, any fac¬

PTSD nightmares are unique in that

tor that increases dream intensity earlier

they replicate, in whole or in part, the ter¬

in the night (e.g., sleep fragmentation or

rifying and often-excruciating experiential

deprivation, jet lag, REM-sensitive medi¬

details of the trauma (Mellman & Pigeon,

cations) might also lead to nightmares at

2005). About 50 percent of patients report

this time. Some nightmares may not induce

such replicative nightmares (Wittmann,

an awakening and only be recalled in the

Schredl, & Kramer, 2007). PTSD night¬

morning or later in the day, possibly be¬

mares also depict modified replays that

cause their associated dysphoric emotions

change details of the trauma but preserve

are less intense; some refer to these as bad

or amplify associated emotions (Hart¬

dreams (Zadra, Pilon, & Donderi, 2006).

mann, Zborowski, Rosen, & Grace, 2001;





Mellman & Pigeon, 2005). So although

are not characteristic of nightmare disor¬

50 percent of combat veterans with PTSD

der because of the loss of skeletal muscle

report dreams containing explicit combat

tone that normally occurs during REM

details (Esposito, Benitez, Barza, & Mell¬

sleep, but they may occur under situa¬

man, 1999), a much greater proportion

tions of emotional stress or sleep frag¬

(83%) report dreams containing threats

mentation (e.g., pregnancy, postpartum

(Esposito et al., 1999) compared with non-

state). Some parents (1.3% to 3.9%) report

PTSD combat controls (46%) (Hall & van

that their preschool children have night¬

de Castle, 1966). PTSD nightmares may

mares often or always. The prevalence

also contain elements of much earlier trau¬

of nightmares increases from ages 10 to

matic and adverse events, or repetitious

13 for both males and females but there¬

but nontraumatic elements (Wittmann et

after continues to increase to ages 20 to

al., 2007). To illustrate, survivors of Hur¬

29 for females but decrease variably for

ricane Iniki reported dreams about general

males. Adult females report having night¬

stressors (74% vs. 48% for controls) and

mares more often than do men, with ratios

about especially stressful life experiences


(67% vs. 37%), but only rarely about the hurricane itself (13%) (Pagel, Vann, & Altomare, 1995). Theoretical and empirical work on night¬ mares from Freud to the present day con¬ verges on, and to some extent supports, the notions that (1) emotion regulation is a normal function of dreaming and (2) night¬ mares are either exemplary expressions or psychopathological disturbances of this function (Nielsen & Lara-Carrasco, 2007). The work has produced several possible mechanisms that may be central to emo¬ tion regulation during dreaming, including desomatization, contextualization, progres¬ sive emotional problem solving, and fearmemory extinction. It provides suggestive evidence that some aspects of dream con¬ tent (e.g., self-character interactions, emo¬ tions), and not simply the physiological state of REM sleep per se, are implicated in the emotion regulation function. There are several recent comprehensive reviews of nightmares available (Levin & Nielsen, 2007; Nielsen, 2010; Nielsen & Zadra, 2010; Phelps, Forbes, & Creamer, 2008; Spoormaker, Schredl, & Bout, 2005). Tore Nielsen








References Esposito, K., Benitez, A., Barza, L., & Mellman, T. (1999). Evaluation of dream content in combat-related PTSD. Journal of Trau¬ matic Stress, 12, 681-687.


in dreams: More intense after abuse and trauma. Dreaming, 11, 115-126. Kuiken, D., Lee, M.-N., Eng, T., & Singh, T. (2006). The influence of impactful dreams on self-perceptual depth and spiritual trans¬ formation. Dreaming, 16, 258-279. Levin, R., & Nielsen, T.A. (2007). Disturbed dreaming, posttraumatic stress disorder, and affect distress: A review and neurocognitive model. Psychological Bulletin, 133, 482-528. Mellman, T. A., & Pigeon, W. R. (2005). Dreams and nightmares in posttraumatic stress disorder. In M. H. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and prac¬ tice of sleep medicine (4th ed., pp. 573578). Philadelphia: Elsevier Saunders. Nielsen, T.A. (2010). Disturbed dreaming as a factor in medical conditions. In M. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practice of sleep medicine (5th ed., pp. 1116-1127). New York: Elsevier. Nielsen, T.A., & Lara-Carrasco, J. (2007). Nightmares, dreaming and emotion regula¬ tion: A review. In D. Barrett & P. McNamara (Eds.), The new science of dreams (pp. 253284). Westport, CT: Praeger Greenwood. Nielsen, T. A., & Zadra, A. (2010). Idiopathic nightmares and dream disturbances asso¬ ciated with sleep-wake transitions. In M. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practice of sleep medi¬ cine (5th ed., pp. 1106-1115). New York:

Elsevier. Pagel, J.F., Vann, B.H., & Altomare, C.A. (1995). Reported association of stress and dreaming—Community background levels and changes with disaster (Hurricane Iniki). Dreaming, 5, 43-50.

Hall, C., & van de Castle, R.I. (1966). The content analysis of dreams. New York: Appleton-Gentury-Crofts.

Phelps, A.J., Forbes, D., & Creamer, M. (2008). Understanding posttraumatic night¬ mares: An empirical and conceptual re¬ view. Clinical Psychology Review, 28(2), 338-355.

Hartmann, E., Zborowski, M., Rosen, R., & Grace, N. (2001). Contextualizing images

Spoormaker, V.I., Schredl, M., & Bout, J.V. (2005). Nightmares: From anxiety symptom





to sleep disorder. Sleep Medicine Reviews, 10, 19-31. Wittmann, L., Schredl, M., & Kramer, M. (2007). Dreaming in posttraumatic stress disorder: A critical review of phenome¬ nology, psychophysiology and treatment.

Psychotherapy and Psychosomatics,


25-39. Zadra, A., Pilon, M., & Donderi, D.C. (2006). Variety and intensity of emotions in night¬ mares and bad dreams. Journal of Nervous and Mental Disease, 194, 249-254.

o Objective and Subjective Dreams

pertain to that person in actuality. The dream may be showing our subjective pic¬ ture of that person or it may be using that

In popular culture, it is commonly assumed

figure to signify an aspect of ourselves. To

that dreams pertain primarily, if not solely,

understand the direction a dream faces, a

to the personality of the individual dreamer.

process of discernment needs to be under¬

This attribution, which corresponds to

taken; this will counteract any tendency to

the ethos of separatism that characterizes

take the dream superficially at face value.

American society, is not found in dream¬

From a collection of dreams made over a

ing cultures. In most indigenous traditions,

10-year period, those determined to be out¬

it is recognized that there are little dreams

ward facing rather than subjective showed

pertaining to the daily life of the dreamer

certain specific characteristics: (1) Their

and big dreams pertaining to the ongoing

imagery is very plain, without fantastical or

life of the tribe.

dreamlike elements; (2) the action is much

In his first essay on dreams, written in

as it would be in waking life; (3) there is

1917, C.G. Jung made a distinction be¬

little or no emotion on the dreamer’s part;

tween subjective dreams, which refer to the

(4) the dreamer often has few if any asso¬

dreamer and their worldview, and objec¬

ciations to the dream, and meaning can be

tive dreams, which refer to the larger world

made of it only when it is considered to be

around. He recognized that these adjectives

outward facing (Sabini, 2006).

were value laden, with objectivity being

Western psychology has contributed to

privileged over subjectivity (Jung, 1966,

an understanding of projection, the sub¬

para. 130). Since the dreaming mind is capa¬

liminal process by which we give over to

ble of distinguishing between inside and out¬

others a tendency or quality that belong to

side, self and other, we might think instead

ourselves. The opposite process, absorb¬

of dreams being inward facing and outward

ing into ourselves a quality or tendency

facing (Sabini, 2008). Dreams themselves

that belongs to others, has received much

often indicate which direction they face: we

less attention. This distinction between the

dream of being inside our childhood home

subjective and objective dimensions of

or outside on a city street, of repairing the

dreams, by which their contents face in¬

interior of our home or changing the outgo¬

ward or outward, provides an important

ing message on our voicemail.

template for discerning the purpose or

Dreams that refer to a person known

function a dream may have. It is a heu-

to us do not necessarily imply that they

ristically important template with many




Obstructive Sleep Apnoea, Metabolism, and Hormones

possible applications for both dream re¬

apnoea belongs to the metabolic syndrome

search and dreamwork.

cluster—the association with visceral obe¬ Meredith Sabini

sity, male gender preponderance, post¬ menopausal increase of its prevalence, and

References Jung, C.G. (1966). Two essays on analytical psychology. Princeton, NJ: Princeton Uni¬ versity Press. Sabini, M. (2006). Dreams about others: How can we recognize them? DreamTime, 23(2), 32-33. Sabini, M. (2008). Encountering the primordial self. Jung Journal: Culture & Psyche, 2(4), 34-69.

systemic effects, for example, hypertension and diabetes. OSA is also more common in ethnic minorities (African Americans and Hispanics) who are at increased risk of the metabolic syndrome and diabetes.

OSA, Diabetes, and Metabolic Syndrome There is a high prevalence of OSA in obese individuals and a high prevalence

Obstructive Sleep Apnoea, Metabolism, and Hormones

of obesity in patients with OSA (Svatikova et al., 2005). The impact of obe¬ sity on OSA includes impact on upper

Obstructive sleep apnoea (OSA) is a com¬

airway anatomy, ventilatory control, and

mon condition that is increasing in preva¬

pharyngeal airway tone. Leptin resistance

lence in parallel with obesity and type-2

in obesity may also have an impact on

diabetes mellitus. While obesity is a key

ventilatory control. OSA may perpetu¬

factor in the development of OSA, only up

ate obesity through effects on sleep frag¬

to 50 percent of OSA is due to obesity. With

mentation and loss. Visceral obesity is a

obesity being a key player in OSA, any in¬

major driver for type-2 diabetes mellitus

dependent impact of OSA on circulating

and the metabolic syndrome. Diabetes is

metabolic hormones and/or metabolism is

more prevalent in patients with sleep-dis¬

difficult to confirm definitively. Neverthe¬

ordered breathing (SDB, which includes

less, accumulating evidence points toward

OSA) and this relationship appears to be

important interactions among OSA, hor¬

independent of other risk factors. How¬

mones, and metabolism. These interactions

ever, it is not clear whether SDB is causal

can be through hormone-related conditions

in the development of diabetes. A study

(e.g., obesity, hypothyroidism) predispos¬

examining the potential association of

ing to or aggravating OSA, and/or OSA

OSA with the metabolic syndrome found

(through mechanisms such as intermittent


hypoxia and increased sympathetic ner¬

ated with increased systolic and diastolic

vous system activity) predisposing or ag¬

blood pressure, higher fasting insulin and

gravating hormone-related conditions such

triglyceride levels, decreased HDL cho¬

as diabetes mellitus, hypertension, and the

lesterol, increased cholesterokHDL ratio,

metabolic syndrome. A number of asso¬

and a trend toward higher homeostatic

ciated features of OSA suggest that sleep

model assessment (a measure of insulin





Obstructive Sleep Apnoea, Metabolism, and Hormones


resistance) values. They also found that

duration of CPAP treatment. Ongoing

metabolic syndrome was 9.1 times (95%

and future studies should clarify whether

confidence interval 2.6, 31.2: p < .0001)

CPAP improves diabetes control and pre¬

more likely to be present in patients with

vents or delays diabetes complications.

OSA (Coughlin, Mawdsley, Mugarza, Calverley, & Wilding, 2004). The prevalence of OSA in patients with

Hypothyroidism and Acromegaly

type-2 mellitus ranges from 20 percent to

Hypothyroidism is a common condition

as high as 80 percent depending on the pop¬

(more common in women) associated with

ulation studied and the study setting (Fos¬

weight gain and dyslipidemia. It can pre¬

ter et al., 2009). The association between

dispose to obstructive sleep apnea through

OSA and glucose metabolism is complex

not only weight gain but also through mu-

(Wolk & Somers, 2007). A common con-

copolyscacharide and protein deposition in

founder in the studies is visceral obesity.

the pharynx. Testing for hypothyroidism is

Data from animal models of hypoxia show

thus important in patients presenting with

that intermittent hypoxia can induce insu¬

OSA, although in the majority of cases,

lin resistance. Insulin resistance is also ob¬

the two conditions are coincidental. Acro¬

served in physiological hypoxia in humans

megaly is a rare disease that affects both

such as at high altitude and in pathological

sexes equally and has a prevalence rate

conditions associated with hypoxia such

between 38 and 60 cases out of 1,000,000

as chronic obstructive pulmonary disease.

population. Acromegaly is the result of

Apart from hypoxia, human laboratory

excess growth-hormone secretion usually

sleep-deprivation studies show that sleep

caused by a pituitary tumor. This excess of

loss is associated with insulin resistance.

growth hormone leads to an insidious de¬

Sleep loss and fragmentation can enhance

velopment of coarse facial features, bone

levels of insulin counter-regulatory hor¬

growth, and soft tissue swelling. A large

mones such as cortisol. OSA is also char¬

number of publications have described the

acterized by a pro-inflammatory state and

association between sleep apnoea and ac¬

elevated cytokine levels (e.g., tumor ne¬

romegaly. A correlation has been estab¬

crosis factor-a), which may lead to insu¬

lished between craniofacial changes and

lin resistance (Ciftci, Kokturi, Bukan, &

the presence and severity of apnoeas. Other

Bilgihan, 2004). If OSA has an independent relationship

mechanisms for sleep apnea in acromeg¬

with insulin resistance, then treatment

in ventilatory control, and obesity. Treat¬

with continuous positive airway pressure

ment of acromegaly improves OSA. Some

(CPAP) should improve insulin sensitiv¬

have suggested that growth-hormone de¬

ity. Studies on the effect of CPAP have,

ficiency, as occurs commonly in patients

however, reported conflicting results. The

treated for pituitary disorders, may also

reasons for conflicting findings include

be associated with OSA; further studies

patient selection, initial diabetes control,

are required to investigate this potential

diabetes duration, control treatments, and


aly include pharyngeal edema, alterations




Obstructive Sleep Apnoea, Metabolism, and Hormones

Sex Hormones and Polycystic Ovarian Syndrome (PCOS)

is independent of visceral adiposity is un¬ clear. OSA treatment with CPAP in women with PCOS has been shown to improve in¬

Decreased libido is frequently reported

sulin sensitivity and reduce blood pressure.

in male patients with OSA. Reduced li¬

These responses are, however, dependent

bido has also been observed in women

on associated degree of obesity and CPAP

with OSA. Few studies have examined

usage duration.

the impact of CPAP treatment on sexual dysfunction. OSA is associated with de¬ creased pituitary-gonadal function; low


luteinizing hormone and testosterone lev¬

The metabolic syndrome represents a con¬

els are observed suggesting a central prob¬

stellation of cardiovascular risk factors and

lem (central hypogonadism). While these

is developing into a major public health

alterations may be related to obesity, some

problem. The increased prevalence of the

may be secondary to sleep deprivation and/

metabolic syndrome is linked to the epi¬

or intermittent hypoxia (Grunstein et al.,

demic of obesity, which is also accompa¬

1989). Androgens may have an influence

nied by an increasing prevalence of OSA.

on ventilatory control. Androgen replace¬

OSA and the metabolic syndrome show

ment may exacerbate preexisting OSA, al¬

many common features, and in fact, may

though evidence for this is weak.

often coexist. The coexistence of OSA

PCOS is defined as oligoovulation or

with the metabolic syndrome may contrib¬

anovulation, hyperandrogenemia or clini¬

ute to the clustering of abnormalities de¬

cal manifestations of androgen excess,

fined as the metabolic syndrome and may

and polycystic ovaries as demonstrated

have widespread implications for cardio¬

by ultrasonography. It is the most com¬

vascular morbidity and mortality. Whether

mon endocrine-related condition of re¬

the association of OSA with the metabolic

productive-aged women, affecting nearly

syndrome and diabetes is independent of

four million women in the United States

visceral adiposity is debatable. Neverthe¬

alone. Obesity is seen in many of these

less, OSA may independently contrib¬

women and is frequently central in nature

ute to morbidity and mortality in patients



with the metabolic syndrome and diabetes

with PCOS have an increased prevalence

mellitus. OSA is associated with several

of type-2 diabetes and lipid abnormalities.

hormone abnormalities and endocrine dis¬

Insulin resistance, hyperinsulinemia, and

orders. Clinical vigilance is necessary to

beta-cell dysfunction are common in PCOS

recognize these associations so that appro¬

(Diamati-Kandarakis, 2006). Women with

priate treatment can be instituted. Under¬

PCOS are up to 30 times more at risk of

standing the associations of hormones with

OSA compared to women without PCOS.

OSA will increase our understanding of the

Also, women with PCOS and OSA are

potential role of various hormones in ven¬

more likely to be insulin resistant. Whether

tilatory control and pharyngeal anatomy,

the association between PCOS and OSA

and the roles of sleep fragmentation, short

waist-to-hip ratio).

Olfactory Stimuli and Dreams

sleep duration, and intermittent hypoxia on endocrine function. Marzieh Hosseini Araghi and Shahrad Taheri

See also: entries related to Hormones in Sleep; entries related to Sleep and Development

Note Both Dr. Shahrad Taheri and Dr. Marzieh Hosseini Araghi are funded by the National Institute for Health Research (NIHR) through the Collaborations for Leadership in Applied Health Research and Care for Birmingham and Black Country (CLAHRC-BBC) program. The views expressed in this publication are not nec¬ essarily those of the NIHR, the Department of Health, NHS South Birmingham, University of Birmingham, or the CLAHRC-BBC Theme 8 Management/Steering Group.

References Babu, A.R., Herdegen, J., Fogelfeld, L., Shott, S., & Mazzone, T. (2005). Type 2 diabe¬ tes, glycemic control, and continuous pos¬ itive airway pressure in obstructive sleep apnea. Archives of Internal Medicine, 165, 447-452. Blanco, P., Blanco-Ramos, J.J., Zamarron Sanz, M.A., Souto Fernandez, C., Mato Mato, A., & Lamela Lopez, J. (2004). Acro¬ megaly and sleep apnea. Archivos de Bronconeumologia, 40, 355-359. Ciftci, T. U., Kokturi, O., Bukan, N., & Bilgihan, A. (2004). The relationship between serum cytokine levels with obesity and ob¬ structive sleep apnea syndrome. Cytokine, 28, 87-91. Coughlin, S.R., Mawdsley, L., Mugarza, J. A., Calverley, P. M., & Wilding, J. P. (2004, May). Obstructive sleep apnoea is indepen¬ dently associated with an increased preva¬ lence of metabolic syndrome. European Heart Journal, 25(9), 735-741. Diamati-Kandarakis, E. (2006). Insulin resis¬ tance in PCOS. Endocrine, 30, 13-17.


Foster, G. D., Sanders, M.H., Millman, R., Zammit, G., Borradaile, K. E., Newman, A.B., . . . Sleep AHEAD Research Group. (2009). Obstructive sleep apnea among obese patients with type 2 diabetes. Diabe¬ tes Care, 32(6), 1017-1019. Grunstein, R. R., Handlesman, D. J., Lawrence, S. J., Blackwell, C., Caterson, I.D., & Sulli¬ van, C.E. (1989). Neuroendocrine dysfunc¬ tion in sleep apnea: Reversal by continuous positive airways pressure therapy. Journal of Clinical Endocrinology and Metabolism, 68, 352-358.

Punjabi, N. M. (2008). The epidemiology of adult obstructive sleep apnea. Proceed¬ ings of the American Thoracic Society, 5,

136-143. Svatikova, A., Wolk, R., Garni, A. S., Pohanka, M. & Somers, V. K. (2005). Interactions be¬ tween obstructive sleep apnea and the meta¬ bolic syndrome. Current Diabetes Report, 5, 53-58. Svatikova, A., Wolk, R., Lerman, L. O., Juncos, L.A., Greene, E. L., McConnell, J. P. & Somers, V. K. (2005). Oxidative stress in obstructive sleep apnoea. European Heart Journal, 26, 2435-2439. Tasali, E., & Ip, M. S. (2008). Obstructive sleep apnea and metabolic syndrome: Alterations in glucose metabolism and inflammation. Proceedings of the American Thoracic So¬ ciety, 5, 207-217.

Wolk, R„ & Somers, V.K. (2007). Sleep and the metabolic syndrome. Experimental Physiology, 92, 67-78.

Olfactory Stimuli and Dreams Whether and how external stimuli are processed during sleep has been studied mainly by two different paradigms: eventrelated potentials and incorporation into dream content. Using olfactory stimuli is of interest because of several reasons.




Olfactory Stimuli and Dreams

First, Stuck et al. (2007) showed that ol¬

smelled like lemons instead of garde¬

factory stimuli without trigeminal com¬

nias. (Trotter et al., 1988, p. 95)

ponents such as hydrogen sulfide do not cause arousals even in high concentrations.

No effect of the pleasantness of the stim¬

On the other hand, Stuck, Weitz, Hor-

uli (pleasant stimuli: coffee, peanut butter,

mann, Maurer, and Hummel (2006) found

roses, cinnamon, chocolate, lemon; un¬

that olfactory event-related potentials can

pleasant stimuli: wood alcohol, dirty ash¬

be measured during sleep indicating that

tray, match smoke, mold, dog feces, onion)

chemosensory stimuli are processed by the

on dream emotions was reported (Trotter

sleeping brain. Secondly, olfactory stim¬

et al., 1988). Several methodological is¬

uli were processed differently within the

sues, such as lack of control condition and

brain compared to auditory stimuli: This

presentation technique (inducing arous¬

includes the predominantly ipsilateral pro¬

als), however, limit the generalizability of

cessing of the olfactory stimuli, and the al¬

this findings. The second study (Schredl

most direct projection from the olfactory

et al., 2009) used a sophisticated stimula¬

bulb to the amygdala (areas for the pro¬

tion methodology (stimulation without dis¬

cessing of memories and emotions) and

turbing the sleeper, no odor present at the

the association to the hippocampus via the

moment of awakening, control condition)

transitional entorhinal cortex. The fact that

and did not find any explicit incorporation

olfactory information processing largely

of olfactory stimuli in the dream reports

bypasses the spinal cord, the brain stem,

(N = 15 participants). In accordance with

and the thalamus—in contrast to all other

the specific processing of olfactory stim¬

sensory systems—explains the small num¬

uli within the brain, the emotional quality

ber of arousals after stimulation because

of the olfactory stimuli using H2S (smell

thalamic reticular nuclei are involved in

of rotten eggs) and phenyl ethyl alcohol

arousal generation (Stuck et al., 2007).

(PEA) (smell of roses) affected the emo¬

Two sleep laboratory studies have been

tional content of dreams: the positively

conducted in this area so far. Trotter, Dal¬

toned stimulus yielded more positively

las, and Verdone (1988) carried out a small

toned dreams, whereas the negative stimu¬

pilot study with five participants to study

lus was followed by more negatively toned

the effect of olfactory stimuli on dream


content. The incorporation rate was 19

The findings indicate that olfactory

percent (79 successful trials in 22 nights).

stimuli are processed by the sleeping

The following example was reported by a

brain; it would be interesting to carry out

participant after presentation of a freshly

learning experiments (associating specific

cut lemon:

odors with declarative material) to study whether this declarative material is in¬

I dreamed I was in Golden Gate Park.

corporated into subsequent dreams if the

I was walking by some gardenias. They

corresponding odor cue is presented dur¬

were just opening. All of a sudden, I

ing sleep—as olfactory stimuli might en¬

could smell the gardenias, but they

hance sleep-related memory consolidation

Overgeneral Memories


(Rasch, Buchel, Gais, & Born, 2007). It

abilities, and mood regulation. Overgen¬

would also be interesting to study the ef¬

erality refers to a lack of specificity when

fect of positively toned olfactory stimuli on

recalling a certain event. Unlike specific


memories, which have taken place in less Michael Schredl

See also: entries related to Dream Content

than one day and are linked with a particu¬ lar place and time, overgeneral memories usually take place over a range of time. Be¬


cause that period of time may be definite

Rasch, B., Buchel, C., Gais, S., & Born, J. (2007). Odor cues during slow-wave sleep prompt declarative memory consolidation. Science, 775(5817), 1426-1429.

(i.e., have an explicit beginning and end¬

Schredl, M., Atanasova, D., Hormann, K., Maurer, J.T., Hummel, T., & Stuck, B.A. (2009). Information processing during sleep: The effect of olfactory stimuli on dream content and dream emotions. Jour¬ nal of Sleep Research, 18, 285-290. Stuck, B. A., Stieber, K., Frey, S., Freiburg, C., Hormann, K., Maurer, J.T., et al. (2007). Arousal responses to olfactory or trigemi¬ nal stimulation during sleep. Sleep, 30, 506-510. Stuck, B. A., Weitz, H., Hormann, K., Maurer, J.T., & Hummel, T. (2006). Chemosensory event-related potentials during sleep— A pilot study. Neuroscience Letters, 406, 222-226. Trotter, K„ Dallas, K„ & Verdone, P. (1988). Olfactory stimuli and their effects on REM dreams. Psychiatric Journal of the Univer¬ sity of Ottawa, 13, 94-96.

ing) or be less distinct, overgeneral memo¬ ries tend to be more variable than specific memories. For example, literature has defined three subtypes of overgeneral memories: categoric, extended, and lifetime period. Categoric memories refer to a series of

repeated events or a single event that oc¬ curs multiple times (e.g., brushing my teeth every morning; visiting my grandmother’s house every year for Christmas dinner). Extended nonspecific memories are mem¬

ories that have continued for more than one day, but still have a distinct beginning and end (e.g., being sick with pneumonia, tak¬ ing a semester of calculus, traveling to Ni¬ agara Falls on vacation). Lifetime-period

memories (Conway & Pleydell-Pearce, 2000) usually have a less clear beginning and end, but demonstrate basic thematic knowledge about general locations, activi¬ ties, plans, behaviors, etc., that are char¬ acteristic of a certain period of time (e.g.,

Overgeneral Memories

when / was young 1 used to be afraid of the dark; when I was dating my high school

Autobiographical memory is the aspect

boyfriend 1 wanted to become a chef).

of memory that is concerned with the rec¬



ollection of personally experienced past


events. It is of fundamental significance to

(Conway & Pleydell-Pearce, 2000, p. 261),

an individual’s sense of self, and thus, is

autobiographical memories are sensi¬

related to other aspects of human function¬

tive to cues. Most studies investigating

ing such as goal pursuit, problem-solving

autobiographical memory use a cuing










Overgeneral Memories

methodology referred to as the autobio¬

(feelings of extreme sadness and hopeless¬

graphical memory test (AMT). During

ness), cognitive changes (low self-esteem,

the AMT, both positively (e.g., happy, ex¬

guilt, memory and concentration difficul¬

cited, proud) and negatively (e.g., scared,

ties), changes in behavior and motivation

angry, disappointed) valenced cue words

(feeling agitated or slowed down, reduced

are presented to participants. Participants

interest in social or recreational activi¬

are prompted to recall if a specific event

ties), and changes in bodily functioning

reminds them of that word. In response

(sleep, appetite, energy). Thus, it is not

to cues, executive control processes often

surprising that numerous studies of over¬

reshape or recall autobiographical knowl¬

generality in autobiographical memory is

edge that is salient to a person’s working

correlated with poor problem-solving per¬

sense of self. In accordance with this no¬

formance (Goddard, Dritschel, & Burton,

tion, several studies have demonstrated

1996) and the prediction of persistence of

that not only do suicidally depressed pa¬

depression (Dalgleish, Spinks, Yiend, &

tients usually respond more slowly to pos¬

Kuyken, 2001).

itively valenced cues, but they reported

In addition, observing overgenerality

more overgeneral memories than healthy

holds significance because memory re¬

control participants. Perhaps more inter¬

mains nonspecific in people with a history

estingly, several studies have replicated

of emotional disorder, even if not currently

the finding that group differences between

in an episode. The fact that overgenerality

suicidal patients and controls are due to in¬

can be seen without needing to be activated

creased retrieval of categorical memories,

by low mood indicates that overgenerality

with no such differences in numbers of ex¬

in autobiographical memory may act as a

tended memories (Williams et al., 2007).

between-episode marker of future vulner¬

Williams and colleagues reviewed re¬

ability to depression. Thus, not only may

search examining the specificity of mem¬

nonspecific memory assessed when one

ory in people suffering from affective

is not depressed predict later mood dis¬

disorders (e.g., major depressive disor¬

turbance, but overgenerality appears to be

der [MDD], posttraumatic stress disorder

more of a trait marker that causes a vul¬

[PTSD], etc.). Overall, emotionally dis¬

nerability to depression, rather than a state

turbed patients tend to summarize catego¬

marker of depression (Brittlebank, Scott,

ries of events rather than retrieving a single

Williams, & Ferrier, 1993).

episode when asked to recall autobiograph¬

Because self-concept and autobiograph¬

ical experiences (Williams et al., 2007).

ical memories are so intimately related, the

Such findings may suggest that overgen¬

level of specificity when recalling a certain

eral memories serve to protect against re¬

event has obvious implications for one’s

call of painful personal events.

sense of self. Discrepancies between re¬

A closer look at patients with MDD

called memories and one’s perceived self

explains the far-reaching effects of over¬

may produce feelings of internal inconsis¬

general memory recollection. In MDD,

tency. When memories are specific, self¬

patients experience emotional changes

discrepancies usually provide the type of

Overgeneral Memories


psychological tension necessary to mo¬

supports the correlation between sleep dys¬

tivate a person to set personal goals and

function and mood dysregulation. With the

generate plans to attain those goals—

negatively valenced mnemonic content of

demonstrating how memory affects moti¬

REM sleep, and REM’s role in distorted

vation and goal pursuit. In turn, emotions

memory functions in both PTSD and de¬

are often impacted by goal pursuit and goal

pression (McNamara, Auerbach, Johnson,

attainment, evidencing autobiographical

Harris, & Doros, 2010), it would not be far¬

memories’ ultimate role in mood regula¬

fetched to consider a correlation between

tion. Both a top-down and bottom-up pro¬

REM sleep and overgeneral memories.

cess, “autobiographical knowledge can ...

A pilot study investigating how sleep fa¬

constrain the goal structure of the working

cilitates the production and recall of over¬

self, but it is also evident that the working

general memories was conducted in 2009

self may determine what autobiographical

with 50 healthy, college-aged participants.

knowledge can be accessed and how that is

Participants slept in the sleep lab for two

to be constructed into a memory” (Conway

consecutive nights. While the first night

& Pleydell-Pearce, 2000, p. 272). In fact,

was a habituation night, the second night

very vivid and specific memories often

participants underwent an overnight poly¬

arise in response to experiences in which

somnography in which electroencepha¬

the self and goals are highly integrated (e.g.,

lography activity was monitored as each

experiences of goal attainment or progress

participant was awoken twice by a sleep

toward attainment) or markedly inhar¬

technician (once in REM sleep and once

monious (e.g., plan failure) (Conway &

in NREM sleep).

Pleydell-Pearce, 2000).

All subjects performed a series of cogni¬

In particular, Beike and Landoll (2000)

tive tasks four times throughout the night:

investigated how several types of cognitive

once before going to bed, once after being

reactions to personally discordant recalled

awoken from REM sleep, once after being

events could resolve feelings of internal

awoken from NREM sleep, and once in

inconsistency. Providing justifications for

the morning. The tasks were both written


inconsistency, recruiting additional

and spoken, taking about 15 minutes to

specific events that oppose those recalled,

complete each time. Some of these tasks

and putting the event behind oneself (clo¬

required participants to recall a dream

sure) were three cognitive reactions found

or dreams they might have had prior to

to moderate the relationship between in¬

awakening. Another task was similar to

consistent recall and well-being. While

the AMT, where participants were pre¬

overgeneral memories may promote the

sented with positively (e.g., happy), neg¬

perpetuation of depression and other affec¬

atively (e.g., lonely), and neutrally (e.g.,

tive disorders, gaining control of memory,

apathetic) valenced cue words during each

particularly memory specificity may have

condition. They then were asked to recall

far-reaching implications for mental health.

a personal memory in response to each

While the role of memory specificity

word, recording the memory and providing

and sleep is less obviously related, research

its approximate date on audio tape. Each




Overgeneral Memories

cued memory was later transcribed verba¬

her new college friends were her new best

tim and blindly scored for specificity.

friends. And I was just really apathetic to¬

Excluding memories that were recalled

wards the whole situation, even though I

after positive and negative cue words (be¬

should have really cared about it, just be¬

cause such emotionally valenced words are more likely to elicit specific responses), overgeneral memories were more frequent

cause that’s how she’s kind of always been. She’s always been really easily influenced. So ... I just really didn’t care about it. It wasn ’t anything new to me. ”

after REM sleep than after NREM-sleep awakenings. In REM sleep, 38.6 percent

This participant reported an unrelated

of memories were overgeneral while only

overgeneral memory in response to the

27.9 percent of NREM-sleep memories

neutral cue word (apathetic) presented

were overgeneral (y2(l, 27 = 87) = 0.02,

after her REM awakening. The dream that

p < .05) (Abrams & McNamara, 2009).

she recalled after her REM awakening ap¬

Findings suggest that REM sleep may help

pears negative, as she accounts the recent

to modulate memories via generation of

end of a friendship and the awkwardness

nonspecific memories.

she felt at an imaginary Thanksgiving din¬

In addition, findings support the pos¬

ner when she realized their families were

sibility that REM sleep is depressogenic,

still friends. In the previous case, one could

implying that REM sleep may help to cre¬

argue that REM sleep may have contrib¬

ate nonspecific memories that contribute

uted to the production of an overgeneral

to negative ruminations central to depres¬

memory as if to protect the participant

sion. Following is an example of an over¬

from a painful past event (i.e., the loss of

general memory protecting from a painful

a friendship). Although dreams are not al¬

past event:

ways based on reality, they often do play a role in memory consolidation and the

Negative REM Dream

processing of information collected during the day. In the previous case, the dream

“I dreamt about my friend ... me and my

recalled after awakening from REM was

roommate stopped being friends ... a month

triggered by a recent event in her life, and

ago. So, I think / dreamt about her. And. . .

her tendency toward overgenerality may

we were at Thanksgiving together and it was

have guarded the participant from having

just really awkward. And it ended up that our

to process the painful specifics surround¬ ing the event.

families were actually friends together. ”

Although the pilot study had several

Neutral Memory Recalled after that REM Awakening

limitations such as a small sample size (N - 50), a lack of diversity in the sam¬

ple (predominantly college aged, Ameri¬ • “I was really apathetic about a month ago

can, Caucasian, and middle class), and the

when one of my best friends got . . . really

use of only self-reported measures of well¬

wrapped up in college and with her new

being, the study highlights the potential

friends. And she was just . . . saying how

role of REM sleep in overgeneral memory

Overgeneral Memories

production. Thus, findings further support the relationship between mood dysregulation and sleep dysfunction. Overall, the widely replicated finding that overgeneral memories are more fre¬ quently recalled in patients with affective disorders than healthy controls suggests a strong relationship between overgen¬ eral autobiographical memories and selfconcept. Whether overgeneral memories cause, are caused, or just contribute to mood dysregulation is less obvious. How¬ ever, because autobiographical memories either reflect or project an individual’s selfconcept, autobiographical memories and the degree of specificity in which they are

Brittlebank, A.D., Scott, J., Williams, M.G., & Ferrier, I.N. (1993). Autobi¬ ographical memory in depression: State or trait marker? British Journal of Psychia¬ try, 162, 118-121. Conway, M.A., & Pleydell-Pearce, C.W. (2000). The construction of autobiograph¬ ical memories in the self-memory system. Psychological Review, 107, 261-288. Dalgleish, T., Spinks, H., Yiend, J., & Kuyken, W. (2001). Autobiographical memory style in seasonal affective disorder and its re¬ lationship to future symptom remission. Journal of Abnormal Psychology,

Goddard, L., Dritschel, B., & Burton, A. (1996). Role of autobiographical memory in social problem solving and depression.

recalled will either reflect or project onto

Journal of Abnormal Psychology,

other aspects of their functioning.


Emily Abrams

References Abrams, E., & McNamara, P. (2009, October 16). Overgeneral memories are more frequent after REM than NREM sleep awakenings. Poster presented at the UROP Symposium at Boston University, Boston, MA. Beike, D.R., & Landoll, S.L. (2000). Striving for a consistent life story: Cognitive reac¬ tions to autobiographical memories. Social Cognition, 18, 292-318.




McNamara, P., Auerbach, S., Johnson, P., Har¬ ris, E., & Doros, G. (2010). Impact of REM sleep on distortions of self concept, mood and memory in depressed/anxious partici¬ pants. Journal of Affective Disorders, 122, 198-207. Williams, J., Thorsten Barnhofer, M.G., Crane, C., Hermans, D., Raes, F., Watkins, E., & Dalgleish, T. (2007). Autobiograph¬ ical memory specificity and emotional disorder. Psychological Bulletin, 133, 122-148.

p Parapsychology and Dreams

monitored (Ullman, Krippner, & Vaughan, 1973). The transmitter was given a ran¬

Parapsychology can be defined as disci¬

domly selected envelope and retired to

plined inquiry into reported experiences

a distant room; the envelope contained

and behaviors that seem to defy mainstream

an art print (the target). The transmitter

science’s concepts of space, time, and en¬

would open the envelope, view the target,

ergy. Several parapsychologists (most of

and attempt to send its images to the par¬

them psychologists or psychiatrists) have

ticipant, who, in turn, had been told to at¬

studied dream reports in which these ef¬

tempt incorporating the images into his/her

fects are alleged to have occurred. These

dreams. Experimenters awakened the par¬

unusual dreams have been a topic of fasci¬

ticipant during REM sleep, tape recording

nation throughout the millennia and were

all dream reports, which were later tran¬

usually attributed to supernatural forces,

scribed. Upon the completion of the ex¬

finding their way into the mythologies and

perimental series (typically 8 to 10 nights),

sacred writings of various faiths. However,

outside judges worked blind and indepen¬

the first attempt to study them experimen¬

dently with these transcripts and copies of

tally was published in 1895 by G. Erma-

the art prints, assigning numerical scores

cora, who worked with an Italian claimant


medium who attempted to influence the

These scores were analyzed statistically

dreams of a child, a phenomenon referred

to determine if the correct transcript-

to as telepathy by parapsychologists. In

target matches differed from the in¬

1966 L. Rhine and colleagues surveyed

correct matches. This occurred often

some 7,000 anecdotal reports of interest to

enough to confirm the telepathy hypoth¬

parapsychologists, noting that nearly two

esis; indeed, a meta-analysis of some 450

thirds reputedly occurred in dreams (Rhine,

nighttime dream sessions at Ullman’s lab¬

Pratt, Stuart, Smith, & Greenwood, 1966).

oratory produced odds of 75 million to 1

In 1966 M. Ullman and colleagues initi¬

against achieving such results by chance.

ated a decade-long experimental study in

Notably, five professional magicians vis¬

a medical center sleep laboratory; a pro¬

ited the laboratory and examined the re¬

tocol was devised in which a telepathic

search protocol, concluding that it was too

transmitter would interact with a research

tight to permit unconscious cueing or con¬

participant who would then enter a sound¬

scious deceit on the night of the experi¬

proof sleep room for the night, with elec¬

ment, the only possibilities for chicanery

trodes attached so that periods of rapid

being on the part of staff members who

eye movement (REM) sleep could be

could have altered the transcripts before







Parapsychology and Dreams

sending them to the judges or on the part of

Ullman experiments and those done else¬

those statisticians who analyzed the data.

where (principally in British university set¬

As a result, the transcribers were advised

tings with participants who stayed at home

to keep duplicate copies of the transcripts

and were awakened at random intervals by

should an investigation be called for, and

telephone) C. Roe and S. Sherwood (2009)

the analysis was assigned to outside stat¬

concluded that “combined effect size esti¬

isticians who were not members of the

mates for both sets of studies suggest that

laboratory staff.

judges could correctly identify target ma¬

Several attempted replications were car¬

terials more often than would be expected

ried out by investigators in other laborato¬

by chance, using dream reports” (p. 211).

ries. Many well-known dream researchers

They also reported a significant difference

initiated these studies, including I. Strauch

between the two datasets; the results favor¬

and D. Foulkes, who obtained negative re¬

ing those carried out at Ullman’s laboratory.

sults; C. Hall, who reported positive results

One psychic claimant participated in

(but with data too sparse to permit statisti¬

two eight-night studies in which he at¬

cal analysis); and G. Globus, who reported

tempted to dream about a target that would

ambiguous results. After examining the

be randomly selected once he awoke; a phenomenon referred to as precognition by parapsychologists; both studies produced significant results but no attempt was made to repeat them in other laboratories. Critics of this body of work cite the lack of replicability. However, S. Krippner (2007) and his associates conducted ret¬ rospective studies indicating a correspon¬ dence between putative telepathic and precognitive dream reports and geomag¬ netic activity, specifically low sunspot activity and electrical storms while par¬ ticipants were dreaming. Hence, if future studies yield greater replicability, and if they are executed under conditions that rule out coincidence, sensory cueing, sta¬ tistical artifacts, and fraud, these data sug¬ gest that there are biological capacities for unusual behaviors that may be sensitive to

Moonchild by Dierdre Luzwick symbolizes what parapsychologists suspect is the hidden tele¬ pathic entanglement of people who, on the surface, seem to be cut off from others. (Repro¬ duced from the original art of Dierdre Luzwick)

geomagnetic activity, bringing these para¬ psychology-derived data closer to similar environment-brain interactions already re¬ ported in mainstream science. Stanley C. Krippner

Parasomnias and Nocturnal Frontal Lobe Epilepsy



(always or often) is 1 to 11 percent. The ae-

Friedman, H.L., & Krippner, S. (2010). Edi¬ tors’ epilogue: Is it time for a detente? In S. Krippner & H. L. Friedman (Eds.), De¬ bating psychic experience: Human poten¬ tial or human illusion? (pp. 195-204). Santa Barbara, CA: Praeger.

tiopathogenesis remains unknown, but an

Krippner, S. (2007). Anomalous experiences and dreams. In D. Barrett & P. McNamara (Eds.), The new science of dreaming (Vol. 2, pp. 285-306). Westport, CT: Praeger. Rhine, J. B., Pratt, J. G., Stuart, C. E., Smith, B. M., & Greenwood, J. A. (1966). Extra¬ sensory perception after sixty years. Bos¬ ton: Bruce Humphries. Roe, C. A., & Sherwood, S. J. (2009). Evidence for extra-sensory perception in dream con¬ tent: A review of experimental studies. In S. Krippner & D.J. Ellis (Eds.), Perchance to dream: The frontiers of dream psychology (pp. 211-238). New York: Nova Science. Ullman, M., Krippner, S., & Vaughan, A. (1973). Dream telepathy. London: Turn¬ stone Books.

underlying impairment of arousal mecha¬ nisms triggering dissociation between the motor component of the awake state and EEG electrical activity (i.e., dissociated state) has been postulated (Mahowald & Schenck, 2005). Nocturnal frontal lobe epilepsy (NFLE) is a partial epilepsy in which seizures, characterized by complex, often bizarre, motor behavior or sustained dystonic posture, occur almost exclusively during sleep (non-REM sleep in 97% of cases). The clinical spectrum of nocturnal frontal lobe seizures (NFLS) comprises distinct paroxysmal sleep-related attacks of vari¬ able semiology, intensity, and duration, representing different aspects of the same epileptic condition (Tinuper & Lugaresi, 2002) (see Table 4). Seizures have a re¬ markable interindividual stereotyped se¬ miology. Due to the rarity of this condition, epidemiological data are lacking. Onset is

Parasomnias and Nocturnal Frontal Lobe Epilepsy Table 3: Parasomnias According to ICSD-2 Parasomnias are defined as “clinical dis¬ orders that are not abnormalities of the processes responsible for sleep and awake states per se but are undesirable physical phenomena that occur predominantly dur¬ ing sleep” (American Academy of Sleep Medicine, 2005). Parasomnias, compris¬ ing a dozen clinical features, are divided into three groups (see Table 3). With the exception of REM behavior disorder, pa¬ rasomnias usually occur during childhood, more often \yith episodic recurrence, but

Arousal disorders Confusional arousals Sleep terrors Sleepwalking

Parasomnias usually associated with REM sleep Nightmares REM behavior disorder Sleep paralysis

Other parasomnias Sleep enuresis

onset or persistence during adulthood is

Source: Adapted from ASDA & American

not rare. The prevalence in the population

Academy of Sleep Medicine (2005).




Parasomnias and Nocturnal Frontal Lobe Epilepsy

mainly during adolescence and males are

is named autosomal dominant NFLE.

more frequently affected. Neurological

Mutations in genes coding for the alfa4,

and neuropsychological examinations and

alfa2, and beta2 subunits of the neuronal

neuroradiological findings are normal in

nicotinic acetylcholine receptor have been

86 percent of cases and interictal and even

identified, confirming genetic heterogene¬

ictal EEG fails to disclose epileptiform ab¬

ity (Marini & Guerrini, 2007).

normalities in half of the patients. Carba-

Since the first description in 1981, the

mazepine completely abolishes NFLS or

problem of the differential diagnosis be¬

gives remarkable relief in two thirds of pa¬

tween NFLS, parasomnias, and pseudosei¬

tients, whereas the seizures prove resistant

zures has been debated (see Table 5). The

to any antiepileptic drug treatment in the

difficulty in differential diagnosis between

remainder (Provini et al., 1999).

NFLE and parasomnias is hampered by the

NFLE is a syndromic entity that in¬

possible coexistence in NFLE patients or

cludes both sporadic and familial cases. In

their relatives of nocturnal parasomnic at¬

familial cases, NFLS recur in an autoso¬

tacks. We recently documented by a large

mal dominant manner and this condition

case-control study a higher frequency of

Table 4: Clinical Features of Nocturnal frontal Lobe Seizures (NFLS) and The Most Common Parasomnias Hypermotor seizures Body movements that can start in the limbs, head, or trunk Complex, often violent behavior Often with a dystonic-dyskinetic component Sometimes with cycling or rocking or repetitive body movements Prevalent in the trunk or legs The patient may vocalize, scream, or swear Fear is a frequent expression Asymmetric, bilateral tonic seizures Sustained non-customary forced position Paroxysmal arousals Bilateral and axial involvement resembling a sudden arousal Opening of the eyes Sitting up in bed Sometimes frightened expression Epileptic wanderings Same beginning as above Semi-purposeful ambulatory behavior Mimicking sleepwalking Source: Tinuper et al. (2007).

Parasomnias and Nocturnal Frontal Lobe Epilepsy


arousal parasomnias not only in patients

complex genetic component may be shared

with NFLE but also in their relatives, sug-

by parasomnias and NFLE causing an im-

gesting an abnormal, possibly cholinergic,

pairment in the pathway controlling phys-

arousal system as the common physiopath-

iological arousal. Prospective studies on

ological substrate (Bisulli et ah, 2010). A

children with parasomnias are needed to

Table 5: Clinical Features of Nocturnal frontal Lobe Seizures (NFLS) and The Most Common Parasomnias Disorders of arousal





Usually 3-6

After 50

Any age







Age at onset (years) Gender





Spontaneous evolution

Tend to disappear

Tend to disappear

Rare spontaneous remission


Episodes / month



Almost every night

Almost every night

Occurrence during

First third

Last third

At least 90 minutes

Any time

Family history of parasomnias

after sleep onset

the night Sleep stage onset of episodes Triggering factors


NREM sleep (st. 3-4)

REM sleep

REM sleep

NREM (mainly st. 2) +/-

++ ++ (sleep deprivation, (stress, traumatic febrile illness)


Episodes / night

Usually one

Usually one

From one to several


Episodes duration

1-10 minutes

3-30 minutes

1-2 minutes

seconds to 3 minutes

















Stereotypic motor pattern Autonomic discharge Consciousness if awakened Recall of the episode on awakening Source: Tinuper et al. (2007).




Parasomnias and Nocturnal Frontal Lobe Epilepsy

clarify the long-term evolution of these


sleep disturbances and verify the percentage

American Academy of Sleep Medicine. (2005). The international classification of sleep dis¬ orders: Diagnostic and coding manual (2nd ed., Ed. ASDA). Westchester, IL: American Academy of Sleep Medicine.

of subjects subsequently developing NFLE. Another crucial clinical point is the semeiological overlap between NFLS and parasomnias. Whereas some ictal fea¬ tures of NFLS seem to be typical of the mesial frontal epileptic zones (asymmet¬ ric tonic posturing), others are hard to confine to a specific cortical frontal area and are quite similar to parasomnic be¬ havior. Furthermore, dystonic-dyskinetic elements suggest an ictal involvement of subcortical structures. Therefore the ictal cortical discharges may not be confined to the orbitofrontal regions but disinhibit other cortical (deep temporal) or subcor¬ tical structures and provoke primitive be¬ haviors (Tassinari, Gardella, Meletti, and Rubboli, 2003). Irrespective of the nature of the causal trigger the complex motor semiology characterizing NFLS and some parasomnias is the same and consists in the activation of repetitive motor patterns related to the activation of central pattern generators. Invasive studies using deep im¬ planted electrodes in drug-resistant NFLE patients could clarify this point. Even though many aspects of parasom¬ nias and NFLE have been clarified in the last two decades, the problem of differen¬ tial diagnosis remains a challenge for cli¬ nicians. The difficulties in distinguishing nocturnal epileptic seizures from parasom¬ nias reflect just one aspect of the intriguing issue of the pathophysiological relation¬ ships between all types of paroxysmal motor behaviors during sleep. Francesca Bisulli and Paolo Tinuper See also: entries related to Sleep Disorders

Bisulli, F., Vignatelli, L., Naldi, I., Licchetta, L., Provini, F., Plazzi, G., . . . Tinuper, P. (2010, April). Increased frequency of arousal parasomnias in families with noctur¬ nal frontal lobe epilepsy: A common mecha¬ nism? Epilepsia, 51(9), 1852-1860. Mahowald, M.W., & Schenck, C.H. (2005). Insights from studying human sleep disor¬ ders. Nature, 43, 1279-1285. Marini, C., & Guerrini, R. (2007). The role of the nicotinic acetylcholine receptors in sleep-related epilepsy. Biochemical Phar¬ macology, 74, 1308-1314. Provini, F., Plazzi, G., Tinuper, P., Vandi, S., Lugaresi, E., & Montagna, P. (1999). Noc¬ turnal frontal lobe epilepsy: A clinical and polygraphic overview of 100 consecutive cases. Brain, 122, 1017-1031. Scheffer, I.E., Bhatia, K. P., Lopes-Cendes, I., Fish, D. R., Marsden, C. D., Andermann, F., Andermann, E., et al. (1994, February 26). Autosomal dominant frontal epilepsy misdi¬ agnosed as sleep disorder (Review). Lancet, 343(8896), 515-517. Tassinari, C.A., Gardella, E., Meletti, S., & Rubboli, G. (2003). The neuroethological interpretation of motor behaviours in “nocturnal-hyperkynetic-frontal-seizures”: Emergence of “innate” motor behaviours and role of central pattern generators. In A. Beaumanoir, F. Andermann, P. Chauvel, L. Mira, & B. Zifkin (Eds.), Frontal lobe sei¬ zures and epilepsies in children (pp. 43-45). New Barnet, UK: B„ John Libbey. Tinuper, P., & Lugaresi, E. (2002). The con¬ cept of paroxysmal nocturnal dystonia. In C. W. Bazil, B. A. Malow, & M. R. Sammaritano (Eds.), Sleep and epilepsy: The clini¬ cal spectrum (pp. 277-282). New York: Elsevier Science.

Partial Sleep Deprivation

Tinuper, P., et al. (2007). Disorders in sleep: Guidelines for differentiating epileptic from non-epileptic motor phenomena aris¬ ing from sleep. Sleep Medicine Reviews, 11, 255-267. Tinuper, P., et al. (2010). Familial frontal lobe epilepsy and its relationship with other nocturnal paroxysmal events. Epilepsia, 57(Suppl. 1), 51-53.


Sleep Deprivation”) except that they are generally milder when the partial sleep loss is for only one to two nights. How¬ ever, chronic partial sleep deprivation that allowed four hours of sleep per night for two weeks resulted in cognitive deficits that were of the same magnitude as those seen after one to two nights of total sleep deprivation. Data also suggest that chronic partial sleep deprivation can have cumula¬ tive or stress-related effects that can differ

Partial Sleep Deprivation

from findings after a short period of total sleep deprivation.

Sleep deprivation refers to having wake¬

Studies have shown that adults are signif¬

fulness that is extended beyond the 16

icantly more sleepy, as measured by falling

hours that is considered a normal day.

asleep more rapidly in naps, after only one

Acute sleep deprivation refers to a single

night with time in bed reduced from eight to

episode of reduced sleep (see the entry

six hours. Sleepiness on the following day

“Acute Sleep Deprivation”). Partial sleep

increases as time in bed decreases. Sleepi¬

deprivation refers to a reduction in total

ness also becomes more apparent as con¬

sleep rather than complete deprivation of

secutive nights of reduced sleep increase.

sleep. The amount of partial sleep loss

One large study found that performance on

can vary from just getting up an hour ear¬

a reaction time task, a memory task, and

lier than normal to many nights with total

a math task was consistently decreased

sleep reduced to four hours or less. Most

after sleep had been restricted to four or

research with partial sleep deprivation has

six hours for several nights. Both time to

examined changes in function after one or

react and the number of very slow or absent

two nights with total sleep reduced to four

responses (called lapses in attention) were

or six hours. Understanding partial sleep

increased. Such data suggest some over¬

loss is important because questionnaires

all cognitive slowing and increases in mi¬

have suggested that 15 percent of normal

crosleeps, .5- to 10-second periods of loss

adults sleep less than six hours per night

of attention where external awareness is

on weekday nights and therefore suffer

briefly lost. These cognitive and response

from some amount of partial sleep depri¬

speed changes suggest that partial sleep de¬

vation on a weekly basis.

privation could also have a negative impact on driving. A study has shown that there

Behavioral Effects

is an increased incidence of sleep-related motor vehicle crashes in drivers sleeping

The general effects of partial sleep depri¬

less than seven hours per night. Empirical

vation are similar to those seen after acute

studies have shown decreased driving abil¬

sleep deprivation (see the entry “Acute

ity in driving simulators after one night of




Partial Sleep Deprivation

sleep reduced to two hours or with sleep

than a short sleep requirement. However,

chronically reduced to four or six hours.

studies have shown that there is an increased mortality risk for individuals reporting less

Physiological Effects of Partial Sleep Deprivation

than six hours of sleep per night. Similarly, an increased risk of coronary events was found in women sleeping seven hours per

A number of physiological changes be¬

night or less in one study and with individu¬

come apparent during partial sleep depri¬

als sleeping less than five hours per night in

vation. For example, subjects allowed three

another study. Sleeping less than five hours

or five hours in bed for seven nights had

per night has also been associated with an

more slow eye movements (consistent with

increased risk of hypertension.

early signs of sleep onset) and an increased latency to pupil constriction. An increase in slow EEG frequencies, often associated

Individual Differences

with sleep onset or sleep, and a decrease in

It is known that some individuals are con¬

higher EEG frequency alpha activity, as¬

sistently more sensitive to the loss of even

sociated with wakefulness, was also found

small amounts of sleep while others are not

in subjects with sleep reduced to four or six

impaired by greater loss of sleep. How¬

hours per night for several nights.

ever, these differences are not always ap¬

Studies of partial sleep deprivation have suggested that sleep restriction to four

parent to the individual and have not been related to other variables at this time.

hours per night for six nights may result in increased sympathetic activation, de¬ creased glucose tolerance, and increased risk of inflammation (as measured by Creactive protein). Other studies of immune function have shown some decrease in im¬ mune function. One study showed that the antibody response to an influenza vaccina¬ tion was decreased by more than 50 percent 10 days after a vaccination that followed six nights of sleep restricted to four hours per night. Responses were the same three to four weeks later, but the results imply that partial sleep deprivation could alter acute immune responses. A number of studies have shown negative health consequences associated with short

Recovery Sleep is all that is needed to reverse the negative effects of partial sleep depriva¬ tion in humans. Partial sleep deprivation typically results in a disproportionate re¬ duction in REM sleep because individu¬ als typically have much more REM sleep near the end of their sleep period (which is cut off during partial sleep deprivation). As a result, recovery sleep after partial sleep deprivation is typically character¬ ized by an increase in total sleep time with a particular increase in REM sleep called REM rebound. Michael H. Bonnet

habitual sleep durations, although it is not always clear that short sleep durations re¬

See also: Acute Sleep Deprivation; entries re¬

flect chronic partial sleep deprivation rather

lated to Sleep Physiology

Phasic Ponto-Geniculo-Occipital/Pontine Wave (PGO/P-Wave)

References Ayas, N.T., White, D.P., Manson, J.E., Stampfer, M.J., Speizer, F. E., Malhotra, A., & Hu, F. B. (2003). A prospective study of sleep duration and coronary heart disease in women. Archives of Internal Medicine, 163(2), 205-209. Banks, S., & Dinges, D.F. (2010). Chronic sleep deprivation. In M. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and prac¬ tice of sleep medicine. Philadelphia, PA: Saunders.


Phasic Ponto-GeniculoOccipital/Pontine Wave (PGO/P-Wave) Prominent phasic events of REM sleep are field potentials in the pontine tegmentum, which begin just prior to the onset of REM sleep and continue through its duration (Datta, 1997, 2010). These field potentials have been recorded in both the lateral ge¬ niculate body (LGB) and the occipital cor¬

Gangwisch, J.E., Heymsfield, S.B., BodenAlbala, B., Buijs, R. M., Kreier, F., Opler, M.G., . . . Malaspina, D. (2008). Sleep du¬ ration associated with mortality in elderly, but not middle-aged, adults in a large US sample. Sleep, 31, 1087-1096.

tex of the cat. Since, in the cat, these field

Philip, P., Sagaspe, P., Taillard, J., Valtat, C., Moore, N., Akerstedt, T., . . . Bioulac, B. (2005). Fatigue, sleepiness, and perfor¬ mance in simulated versus real driving con¬ ditions. Sleep, 28(12), 1511-1516.

tent of the thalamus and cortex. However,

Rosenthal, L., Roehrs, T.A., Rosen, A., & Roth, T. (1993). Level of sleepiness and total sleep time following various time in bed conditions. Sleep, 16, 226-232. Spiegel, K., Sheridan, J.F., & Van Cauter, E. (2002). Effect of sleep deprivation on response to immunization. Journal of the American Medical Association, 288, 1471-1472. Van Dongen, H.P.A., Maislin, G., Mullington, J.M., & Dinges, D.F. (2003). The cumula¬ tive cost of additional wakefulness: Doseresponse effects on neurobehavioral func¬ tions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep, 26, 117-126.

potentials originate in the pons (P) and then propagate to the geniculate (G) and occipital cortex (O), they are called PGO waves. PGO waves in the cat could also be recorded at points throughout the ex¬ such PGO waves reach their highest am¬ plitude in the LGB, primary visual cortex, and association visual cortex. In addition to the pons, thalamus, and cortex, phasic potentials have been recorded in both the oculomotor nuclei and the cerebellum of the cat. Phasic potentials of pontine origin have also been recorded in the amygdala, cingulate gyrus, and hippocampus, sug¬ gesting that PGO waves also occur in the limbic system. More importantly, mapping techniques have demonstrated that (for the cat at least) the pons is the primary site of origin for PGO-wave activity. PGO waves have also been documented and studied in other mammalian species, including non¬ human primates, humans, and rodents. In nonhuman primates, PGO-wave-like pha¬ sic field potentials have been recorded

Vgontzas, A. N., Liao, D., Bixler, E. O., Chrousos, G.P., & Vela-Bueno, A. (2009). In¬ somnia with- objective short sleep duration is associated with a high risk for hyperten¬ sion. Sleep, 32, 491-497.

from the LGB and pons of macaques and in the LGB of baboons. In humans, phasic potentials have been recorded in the striate cortex during REM sleep. Such striate field




Phasic Ponto-Genicuio-Occipital/Pontine Wave (PGO/P-Wave)

potentials are probably cortical compo¬

sleep and are independent of eye move¬

nents of state-specific phasic potentials of

ment; conversely, clusters of PGO waves

pontine origin. PGO waves have also been

(Type II waves) are associated with eye-

recorded in the human pons during and im¬

movement bursts and are typically indic¬

mediately before REM sleep. In rats, initial

ative of REM sleep. Type II PGO-wave

attempts to record potentials in the LGB,

activity accounts for 55 to 65 percent of the

based on PGO-wave recordings in the

total number of PGO waves recorded dur¬

cat, were unsuccessful. Subsequent stud¬

ing REM sleep (Datta & Patterson, 2003).

ies have recorded PGO-like waves in the

Since PGO/P-wave activity always pre¬

pons of the rat that are equivalent to those

cedes REM sleep, several investigators

in the pons of the cat. The initial failures

have proposed that PGO/P-wave mech¬

indicated that state-specific pontine phasic

anisms are causally linked to the cellu¬

waves in rats do not excite LGB neurons in

lar and molecular mechanisms for both

a way that could produce geniculate com¬

the triggering and regulation of the total

ponents of PGO waves. More recently, the

amount of REM sleep. In addition to REM-

absence of PGO-wave-like activity in the

sleep induction, PGO/P-waves have also

rat LGB has shown to be due to the lack

been implicated in several other important

of afferent inputs from P-wave-generating

brain functions such as sensorimotor inte¬

cells to the LGB (Datta, Siwek, Patterson,

gration, learning and memory, dreaming,

& Cipolloni, 1998). This field potential in

self-organization, development of the vi¬

the rat is therefore called a P-wave, since

sual system, and startle responses (Datta,

it does not activate the geniculate nucleus.

1997, 2010; Morrison & Bowker, 1975).

The waveform, amplitude, and fre¬

Although several functional roles for PGO/

quency characteristics of PGO waves re¬

P-wave activity have been proposed, other

corded from the pons, geniculate, and

than memory consolidation these functions

occipital cortex have been most intensively

remain mostly correlative.

examined in the cat (Datta, 1997; Datta &




MacLean, 2007). PGO waves are biphasic

cell-specific lesions, and single-cell re¬

in shape with a duration of 60 to 120 mil¬

cording techniques, the PGO/P-wave gen¬

liseconds and an amplitude between 200

erator in the cat was localized within the

and 300 microvolts. The P-wave in the rat


is equivalent to the pontine component of

(Datta, 1997; Datta & MacLean, 2007).

the PGO wave in the cat, with similar dura¬

Subsequently, using similar experimen¬

tion (75-100 milliseconds) and amplitude

tal techniques to those used in the cat, the

(100-150 microvolts). PGO/P-waves dur¬

P-wave generator in the rat was localized

ing REM sleep can occur as a singlet or

within the dorsal part of the subcoeru-

as clusters containing a variable number

leus nucleus (Datta, 2006; Datta & Patter¬

of waves (three to five waves per burst)

son, 2003). In humans, as in the cat, the

at a density range of 30 to 60 spikes/min¬

PGO/P-wave generator is located in the

ute. Singlet PGO/P-waves, known as Type

C-PBL area. Immunohistochemical iden¬

I waves, occur commonly in non-REM

tification of cholinergic and glutamatergic



Phasic Ponto-Geniculo-Occipital/Pontine Wave (PGO/P-Wave)


cell types in the brainstem indicates that

the predatory mammalian (such as the cat

PGO/P-wave-generating cells in the cat

and human) PGO-wave generator is farther

are capable of synthesizing both acetyl¬

from the LC and instead close to the PPT.

choline and glutamate, and thus these

Since predators rarely face the threat of

cells could be labeled as both cholinergic

predation, there is no advantage to having

and glutamatergic; whereas in the rat, P-

a quick arousal response to any nonthreat¬

wave-generating cells have been identi¬

ening type of noise during REM sleep.

fied by specific monoclonal antibodies as

Furthermore, frequent interruptions could

glutamatergic, but not cholinergic (Datta,

actually harm a predatory animal by pre¬

2006). These P-wave-generating neurons

venting the necessary regenerative func¬

project to the hippocampus, amygdala, en-

tions of REM sleep. Thus, for these types

torhinal cortex, and many other regions of

of noises, the P-wave generator signals the

the brain known to be involved in cogni¬

cholinergic PPT to intensify REM sleep

tive processing. The PGO/P-wave genera¬

rather than wake the animal up by activat¬

tor in both the cat and rat receives afferent

ing the LC.

projections from the raphe nucleus and nu¬

It has been demonstrated that choliner¬

cleus locus coeruleus (LC). These P-wave-

gic activation of the PGO/P-wave genera¬

generating glutamatergic neurons remain

tor increases glutamate release in the dorsal

silent during wakefulness and slow-wave

hippocampus (DH). In addition, P-wave

sleep (SWS), but during the transition

activity has been shown to have a positive

from SWS to REM sleep and throughout

influence on hippocampal theta-wave ac¬

REM sleep these neurons discharge high-

tivity in the DH. Most recently, it has been

frequency spike bursts in the background

demonstrated that the activation of these

of tonically increased firing rates (Datta,

P-wave-generating neurons increases glu¬

2006; Datta & Elobson, 1994).

tamate release and activates postsynaptic

Since the P-wave generator is also in¬

N-Methyl-D-aspartate (NMDA) receptors

volved in sensorimotor integration, the

in the DH. Activation of P-wave-generat¬

differences in the anatomical location and

ing neurons increases phosphorylation of

neurotransmitter identity of the P-wave

the transcription factor cAMP response el¬

generator between the rat and cat may pro¬

ement binding protein (CREB) in the DH

vide a species-specific advantage (Datta,

and amygdala by activating intracellular

2006). Specifically, in prey animals (i.e.,

protein kinase A (PKA). The P-wave-

the rat), the P-wave generator is anatom¬

generating neurons activation-dependent

ically closer to the LC. This shorter dis¬


tance is advantageous during REM sleep

the expression of activity-regulated cyto-

(when animals are naturally paralyzed due

skeletal-associated protein (Arc), brain-

to muscle atonia) because it permits quick

derived nerve growth factor (BDNF), and

communication with the LC for flight re¬

early growth response-1 (Egr-1) genes in

sponse, and facilitates escape from preda-

the DH and amygdala. The P-wave genera¬

tors. This rapid flight response is vital for

tor activation-induced increased activation

the survival of prey animals. In contrast,

of PKA and expression of pCREB, Arc,






Philosophy of Mind and Dream Characters

BDNF, and Egr-1 in the DH are shown

movements. Journal of Neurophysiology,

to be necessary for REM-sleep-dependent

71, 95-109.

memory processing (Datta, Li, & Auer¬ bach, 2008). These findings are significant because they provide the most direct evi¬ dence to substantiate the idea that P-wave generator activation during post-training REM sleep is critical for REM-sleepdependent memory processing. Although the functions of PGO/P-waves remain a mystery in neuroscience, ongoing re¬ search on their generation and functions is very promising. Hopefully in the near fu¬ ture, a complete and detailed mechanism for the regulation of PGO/P-wave genera¬ tor activity will be discovered, which will then be vital to unraveling the functions of PGO/P-wave activity. Subimal Datta See also: entries related to Sleep Physiology

Note This work is supported by the U.S. National Institutes of Health Research grants NS34004 and MH59839.

References Datta, S. (1997). Cellular basis of pontine ponto-geniculo-occipital wave generation and modulation. Cellular and Molecular Neurobiology, 17, 341-365. Datta, S. (2006). Activation of phasic pontinewave generator: A mechanism for sleepdependent memory processing. Sleep and Biological Rhythms, 4, 16-26. Datta, S. (2010). Sleep: Learning and memory. G. F. Koob, M. Le Moal, & R. F. Thompson (Eds.), Encyclopedia of behavioral neuro¬ science (Vol. 3, pp. 218-226). Oxford: Aca¬ demic Press. Datta, S., & Hobson, J. A. (1994). Neuronal ac¬ tivity in the caudo-lateral peribrachial pons: Relationship to PGO waves and rapid eye

Datta, S., Li, G., & Auerbach, S. (2008). Ac¬ tivation of phasic pontine-wave generator in the rat: A mechanism for expression of plasticity-related genes and proteins in the dorsal hippocampus and amygdala. European Journal of Neuroscience, 27, 1876-1892. Datta, S., & MacLean, R.R. (2007). Neurobiological mechanisms for the regulation of mammalian sleep-wake behavior: Reinter¬ pretation of historical evidence and inclu¬ sion of contemporary cellular and molecular evidence. Neuroscience and Biobehavioural Reviews, 31, 775-824. Datta, S., & Patterson, E.H. (2003). Activation of phasic pontine wave (P-wave): A mecha¬ nism of learning and memory processing. In J. Maquet, R. Stickgold, & C. Smith (Eds.), Sleep and brain plasticity (pp. 135-156). Oxford: Oxford University Press. Datta, S., Siwek, D.F., Patterson, E. H., & Cipolloni, P.B. (1998). Localization of pon¬ tine PGO wave generation sites and their anatomical projections in the rat. Synapse, 30, 409^423. Morrison, A.R., & Bowker, R.M. (1975). The biological significance of PGO spikes in the sleeping cat. Acta Neurobiologiae Experimentalis, 35, 821-840.

Philosophy of Mind and Dream Characters How should we regard the characters that appear in dreams? Are they mere inven¬ tions of the mind of the dreamer? Or are they something more than that? To what extent do they exhibit full-fledged criteria of mind and agency? If they do satisfy cri¬ teria of the mental, do they then deserve some sort of moral status as well? To what extent can we accord them the status of the

Philosophy of Mind and Dream Characters


real? Perhaps they are best treated as we

recurring dream series and in dream series

do characters in a novel or a movie. Are

that occur across a single night when they

they simply creatures of the imagination?

appear to remember previous interactions

We will see that this option is not open for

with the dreamer and adjust their behavior

characters in dreams and thus their onto¬

accordingly. Characters can either be de¬

logical status remains undecided.

picted quite realistically or they can simply

Philosophers claim that a person is de¬

just be known to be present. This feature of

fined as a being who is capable of rea¬

dream characters indicates that the dream

soning, who displays intentionality and

ego is using theory of mind skills to cog¬

emotion, who is self-conscious, and who

nize the presence and intentions of other

has an identity that persists through time.

dream characters.

Surprisingly, there is evidence that ei¬

A substantial proportion (between 25%

ther the dreamer (dream ego) or other

and 48% depending on definitions) of male

dream characters display these criteria for

characters is unknown or unfamiliar to the


dreamer (Hall & Van de Castle, 1966;

Besides the dreamer himself, dream

Kahn, Pace-Schott, & Hobson, 2002). In

characters appear in more than 95 percent

an early study of more than 1,000 dreams,

of adult reports of dreams (Hall & Van de

Hall (1963) reported (1) that strangers in

Castle, 1966). In children, dream characters

dreams were most often males; (2) that ag¬

involve people, animals, and unusual be¬

gressive encounters were more likely to

ings like monsters and spirits. In adults, the

occur in interaction with an unknown male

same range of characters appear but with

than with an unknown female or a familiar

a reduction in the frequency with which

male or female; and (3) that unknown males

animals appear. For most adults, the aver¬

appeared more frequently in dreams of

age number of characters in every dream

males than of females. Using the Hall-Van

in addition to the dream ego is between

de Castle system, Domhoff (1996) looked

three and four (Hall, 1951; Kahn, Stick-

at the role of enemies in dreams. Enemies

gold, Pace-Schott, & Hobson, 2000). Male

were defined as those dream characters

characters slightly predominate in wom¬

who typically interacted (greater than 60%

en’s dreams and definitely predominate in

of the cases) with the dreamer in an aggres¬

men’s dreams. Belying the common con¬

sive manner. Those enemies turned out to

ception of dreams as bizarre, dream char¬

be male strangers and animals. Interactions

acters are only very rarely (only 14% of all

with female strangers are predominantly

instances) depicted in any kind of a bizarre

friendly in the dreams of both males and fe¬

manner. Dream characters also show stay¬

males. Domhoff (2003) more recently has

ing power across dream episodes (Foulkes

shown that when male strangers appear in

& Schmidt, 1983)—they are not fleeting

a dream, the likelihood that physical ag¬

inventions of the mind. They change and

gression will occur in that dream far ex¬

grow in way^ appropriate to the narra¬

ceeds what would be expected on the basis

tive of the dream series they are appear¬

of chance. In short, male strangers signal

ing in. Dream characters can reappear in

physical aggression. This is an extremely




Philosophy of Mind and Dream Characters

important result of research on dream con¬

exchanges have repeatedly been demon¬

tent, as it suggests that dream characters

strated to be syntactically well-formed ut¬

may encode selected emotional signals

terances that were entirely appropriate to

in rule-governed ways, thus pointing to a

the dream context.

mental operation whereby characters em¬ body intense emotional charge.

In summary, dream characters seem to be fully imagined or fully realized persons.

While menacing strangers are certainly

They have minds, intentions, desires, and

emotionally compelling, other dream char¬

emotions that operate independently of the

acters that are not strangers can be as well.

will of the dreamer. They may even have

We have all experienced the reappearance

memories. To underline the autonomous

of a loved one in a dream. Whether the

character of dream characters consider the

loved one was lost simply due to breakup

fact that dream characters not only think

or separation or via death, the reappearance

in ways that are totally independent of

in the dream can be startlingly real. In the

the will of the dream ego or dreamer, but

case of bereavement, vivid images of the

they also act in ways that are totally in¬

deceased may persist for years in dreams

dependent of the will of the dreamer. As

(Cookson, 1990). When the loved one ap¬

mentioned previously, dream characters

pears in dreams, there is a tendency to want

appear to initiate emotional encounters

to stay in the dream world and not wake up.

with the dream ego, whether the dream

These sorts of dreams feel like visitations

ego likes it or not. Indeed, some dream

more than fleeting impressions. They are

characters will touch, push, or attack the

experienced as communications from the

dreamer—in ways the dreamer dislikes,

loved one. In this case, the dream charac¬

fears, or hates—events that the dreamer

ter comes alive and temporarily revives the

clearly does not want to happen. When

emotional life of the bereaved—such is the

the dreamer is under attack from some

power of dream characters.

other character, the dreamer never wishes

What do characters (other than the

it were so. Instead, the dreamer does ev¬

dreamer himself) do in dreams? Generally

erything he or she can to flee the aggres¬

speaking, they engage in social interac¬

sion. Aggression against the dreamer is

tions of various kinds. About 68.2 percent

also quite common, at least in dreams that

of aggressive actions and 52 percent of

come from the REM sleep state. If we take

friendly interactions are initiated by other

a very common dream theme such as the

characters. When the dreamer is the initia¬

dreamer being chased by a male stranger

tor of an interaction, most aggressive inter¬

who intends to hurt the dreamer, we will

actions occur in REM dreams and friendly

see that attribution of intentional states and

interactions occur in NREM dreams (Mc¬

other mental states to the dream character

Namara, McLaren, Smith, Brown, & Stick-

does occur as a normal part of the dream¬

gold, 2005; McNamara et al., 2010).

ing process. Fifty-nine percent of the time

Interactions between the dreamer and an¬

the intention of the attacker is known to

other character very often involve conver¬

the dreamer, and 75 percent of the time the

sation or thought exchanges. These verbal

dream ego does nothing to cause or incite

Philosophy of Mind and Dream Characters


the attack (Hall, 1955). The character who


is chasing the dreamer clearly satisfies cri¬

characters we meet in waking life are

teria for possessing mind or consciousness.

not. Whatever the philosophical status of

He can manipulate his attention. Indeed, he

dream characters as full-fledged men¬

keeps his eye on the dreamer and can ad¬

tal agents, our ancestors certainly treated

just his chase route to catch the dreamer

them as such. It may even be said that

as she attempts to lose him. The stranger

dream characters were just as important

also evidences will and volition when he

emotionally to persons in those days as

intends his target and adjusts his actions to

were other waking characters.

get his target. The stranger also evidences

compelling in



Patrick McNamara

awareness of subjective experiences when his rage levels change as a function of the


chase. His mood changes from menacing

Cookson, K. (1990). Dreams and death: An ex¬ ploration of the literature. Omega Journal of Death and Dying, 21, 259-281.

and hate-filled rage to malicious delight and satisfaction when the target is about to be caught. Now all of these consider¬ ations concerning the mental status of the stranger character in a dream also apply, except more strongly to the case of the

Domhoff, G.W. (1996). Finding meaning in dreams: A quantitative approach. New York: Plenum. Domhoff, G.W. (2003). The scientific study of dreams: Neural networks, cognitive devel¬

dreamer herself. The dreamer is a charac¬

opment, and content analysis. Washington,

ter in the dream too. She intends to escape.

DC: American Psychological Association.

She plans and adjusts her behavior accord¬ ingly. She has internal subjective expe¬ riences of fear, terror, relief, or despair, depending on the outcome of the chase. In addition, she can also access memories that attest to her persisting identity across time periods and beyond the current dream epi¬ sode. In lucid dreams, where the dreamer is aware that she is dreaming, other charac¬ ters in the dream demonstrate a striking in¬ dependence of mind and feeling, as well as separate perspectives and knowledge not available to the dreamer (Tholey, 1989). In short, dream characters, both the dreamer and other characters within a dream, appear to satisfy some of the most stringent criteria philosophers have pro¬ duced for mind, agency, or personhood. Dream characters

act as


agents in dreams. They are sometimes

Foulkes, D., & Schmidt, M. (1983). Temporal sequence and unit composition in dream re¬ ports from different stages of sleep. Sleep, 6, 265-280. Hall, C. (1963). Strangers in dreams: An empir¬ ical confirmation of the Oedipus complex. Journal of Personality, 31, 336-345. Hall, C., & Van de Castle, R.I. (1966). The content analysis of dreams. New York: Appleton-Century-Crofts. Hall, C.S. (1951). What people dream about. Scientific American, 184, 60-63. Hall, C.S. (1955). The significance of the dream of being attacked. Journal of Per¬ sonality, 24, 168-180. Kahn, D., Pace-Schott, E., & Hobson, J.A. (2002). Emotion and cognition: Feeling and character identification in dreaming. Con¬ sciousness and Cognition, 11, 34-50. Kahn, D., Stickgold, R., Pace-Schott, E.F., & Hobson, J.A. (2000). Dreaming and wak¬ ing consciousness: A character recognition




Photography and Dreams



of Sleep




From the beginning, an expressive ap¬ proach to image making has woven through

McNamara, P., Andresen, J., Clark, J., Zborowski, M., & Duffy, C.A. (2001). Im¬ pact of attachment styles on dream recall and dream content: A test of the attachment hypothesis of REM sleep. Journal of Sleep Research, 10, 117-127.

the history of photography as an alterna¬

McNamara, P., Johnson, P., McLaren, D., Harris, E., Beauharnais, C., & Auerbach, S. (2010). REM and NREM sleep mentation.

their interest in dreams and synchronistic

International Review of Neurobiology, 92,

69-86. McNamara, P., McLaren, D., Smith, D., Brown, A., & Stickgold, R. (2005). A “Jekyll and Hyde” within: Aggressive versus friendly interactions in REM and non-REM dreams. Psychological Science, 16, 130-136. Merritt, J.M., Stickgold, R., Pace-Schott, E., Williams, J., & Hobson, J. A. (1994). Emo¬ tion profiles in the dreams of men and women. Consciousness and Cognition, 3, 46-60. Tholey, P. (1989). Consciousness and abilities of dream characters observed during lucid dreaming. Perceptual and Motor Skills, 68, 567-578.

tive to documentary photography, and this has included dream imagery. In the 1930s, the surrealists in Paris developed a style of street photography that reflected experiences. In 1941, Bill Brandt, a Brit¬ ish documentary photographer who had briefly been an assistant to Man Ray, pub¬ lished a dream sequence, “Nightwalk: A Dream Phantasy in Photographs,” in Coro¬ net. In the 1950s and 1960s, Minor White,

an influential teacher and founder of the journal Aperture developed an approach to photography as spiritual practice that em¬ phasized exploring inner states by captur¬ ing their equivalents in the physical world. But it was in the 1960s and 1970s that dream imagery became an explicit genre in photography, through the work of early pi¬ oneers such as Jerry Uelsmann (who stud¬ ied with White), Ralph Gibson, and Arthur Tress. Uelsmann’s (1982) work was sem¬ inal; although not about dreams, his use

Photography and Dreams

of multiple enlargers to create complex, dreamlike montages offered an alternative

The use of photography as a medium for

to documentary photography by showing

dream imagery seems paradoxical. Pho¬

that powerful photographic images could

tography is a recording medium; the pho¬

be created in the darkroom.

tographic image captures patterns of light

Photographers have developed different

reflected off objects in the physical world.

strategies for working with dream imag¬

The dream is a subjective experience.

ery. Ralph Gibson shoots straight photog¬

Since dreaming is not an experience of the

raphy, but the dreamy quality of his work

physical world, it would seem an unlikely,

is enhanced in the darkroom through a

if not impossible, subject matter for pho¬

grainy, high contrast look. At the other

tography. Yet artists working in this me¬

end of the spectrum, Uelsmann’s com¬

dium argue that it is precisely the implied

plex method of creating montages in the

verity of the photograph that gives photo¬

darkroom has been succeeded by the dig¬

graphic dream images their power.

ital composite, a form being explored by

Phylogenetic Comparative Methods and Sleep


many contemporary photographers, in¬

brainwaves known as slow-wave activity

cluding his wife, Maggie Taylor. In the

(non-REM or NREM sleep). To obtain data

1970s, Ralph Eugene Meatyard and Les

on sleep in different species, researchers

Krims staged dreamlike tableaus which

typically take an experimental approach in

they then photographed, an approach later

which they use electroencephalograms to

used by Anders Aabel to create images

quantify the relative amounts of REM and

from his own dreams. Arthur Tress, and

NREM sleep. From these studies, we have

later Wendy Ewald, interviewed children

learned much about individual differences

about their dreams and enlisted their help

in sleep; the cyclicity of sleep between

in staging and photographing their dream

these two states; and sleep in relation to

images. Duane Michals stages scenes and

disease, life history events, and external

then creates narrative sequences of photo¬


graphic images that tell dreamlike stories. Richard A. Russo

Imagine that we take the data from many different studies of REM and NREM, ag¬ gregate the data into means for the different


species, and systematically examine varia¬

Aabel, A., & Knarvik, J. C. (2002). Somnia: En bok om drommer. Oslo: Schibsted. Ewald, W. (2000). Secret games: Collabora¬ tive works with children 1969-1999. Zur¬ ich: Scalo Publishers.

tion in sleep characteristics across species (Allison & Cicchetti, 1976; Zepelin & Rechtschaffen, 1974). From such a compara¬ tive approach, we gain new insights to the

Gibson, R. (1970). The Somnambulist. New York: Lustrum Press.

evolution of sleep that are not possible with

Meatyard, R.E. (1974). Ralph Eugene Meatyard (Ed. with text by J. B. Hall). Millerton, NY: Aperture.

ative approach has long been the corner¬

Michals, D. (1984). Sleep and dream. New York: Lustrum Press.

way to understand general evolutionary

Tress, A. (1972). The dream collector. New York: Avon Books. Uelsmann, J. (1982). Jerry N.


Twenty-five years a retrospective (Ed. J. L.

Enyeart). New York: Little, Brown.

studies of individual species. The compar¬ stone of efforts to understand biological diversity because comparison provides a patterns and to test specific hypotheses. More recently, biologists have devel¬ oped statistically rigorous ways to investi¬ gate the evolution of traits on evolutionary trees (Harvey & Pagel, 1991; Martins, 1996; Nunn, 2011). These phylogenetic comparative methods have revolutionized

Phylogenetic Comparative Methods and Sleep

our understanding of evolution and greatly expanded the questions that can be ad¬ dressed. With these methods, for example,

Sleep in mammals and birds occurs in

researchers can investigate how two traits

two physiologically distinct states: active

covary through evolutionary time (corre¬

sleep involves .desynchronized brain states

lated evolution), they can make inferences

and rapid eye movements (REM sleep),

about the evolutionary history of a trait

while quiet sleep involves synchronized

(reconstruct ancestral states), and they can




Phylogenetic Comparative Methods and Sleep

examine how the evolution of a trait has in¬

demonstrated several interesting patterns

fluenced subsequent patterns of speciation

in mammals, including that basal meta¬

and extinction (diversification analysis).

bolic rate and predation risk at the sleep

To appreciate these methods, it is impor¬

site correlate negatively with sleep quotas

tant to understand that the history of life on

(Capellini et al., 2008; Lesku, Roth, Am-

earth can be represented as an evolutionary

laner, & Lima, 2006), and white blood cell

tree, or phytogeny, where the branches rep¬

counts and sleep quotas show a positive

resent lineages of organisms through time,

association (Preston et al., 2009). Results

and the nodes represent speciation events

involving brain size have produced mixed

in which a lineage is separated into two or

results (Capellini et al., 2008; Capellini, Mc¬

more descendent lineages. Two species

Namara, Preston, Nunn, & Barton, 2009;

that share a more recent common ancestor

Lesku et al., 2006), suggesting that cogni¬

are more closely related. More closely re¬

tive factors are not a primary driver of vari¬

lated species also tend to have more similar

ation in sleep architecture. In birds, greater

trait values, that is, the traits show phyloge¬

exposure to predation was shown to reduce

netic signal (Blomberg & Garland, 2002).

slow-wave sleep durations (Roth, Lesku,

Such effects can be seen on a phylogeny,

Amlaner, & Lima, 2006).

with more closely related species having

In terms of reconstructing ancestral states,

more similar sleep characteristics (see Ca¬

the methods again make use of phylogenetic

pellini, Barton, McNamara, Preston, &

signal, and a critical issue involves quanti¬

Nunn, 2008; Preston, Capelleni, McNa¬

fying the statistical confidence we can place

mara, Barton, & Nunn, 2009).

in particular reconstructions. For example,

Researchers interested in sleep have

instead of simply putting a value at an inter¬

used phylogenetic methods to investi¬

nal node on the tree, recent methods allow

gate correlated evolution and ancestral

evolutionary biologists to assess the proba¬

sleep states in mammals, birds, and other

bility of a particular character state (such as

animals (Lesku, Roth, Rattenborg, Am-

presence of REM sleep), or to put a 95 per¬

laner, & Lima, 2009; McNamara, Barton,

cent confidence interval on a quantitative

& Nunn, 2010). In studies of correlated

measure of sleep (such as the duration of

evolution, the methods overcome an im¬

REM sleep). Reconstruction methods have

portant statistical issue—the nonindepen¬

been used less commonly to study sleep.

dence of data points—and provide a way

In one recent example, Nunn et al. (2010)

to estimate the degree of phylogenetic sig¬

used Bayesian methods to estimate that the

nal in the data. When phylogenetic signal

ancestral primate slept for 11.3 hours per

exists, it indicates that different lineages

night, with a 95 percent confidence inter¬

have evolved independently yet still retain

val ranging from 9.4 to 13.4 hours. In this

some variation through common ancestry.

context, it is interesting that the typical

This pattern also means that it is important

human sleep duration of around 8.5 hours

to take phylogenetic history into account

lies outside this confidence interval. In the

when analyzing comparative data. Studies

future, ancestral state reconstructions could

that used phylogeny-based methods have

be used to investigate broader evolutionary

Phylogeny of Sleep

patterns of sleep characteristics, including a formal test for the independent evolution of REM sleep in mammals and birds (Rattenborg & Amlaner, 2010). Charles Nunn

References Allison, T., & Cicchetti, D. V. (1976). Sleep in mammals—Ecological and constitutional correlates. Science, 194, 732-734. Blomberg, S.P., & Garland, T. (2002). Tempo and mode in evolution: Phylogenetic inertia, adaptation and comparative methods. Jour¬ nal of Evolutionary Biology, 15, 899-910. Capellini, I., Barton, R.A., McNamara, P., Preston, B., & Nunn, C.L. (2008). Ecology and evolution of mammalian sleep. Evolu¬ tion, 62, 1764-1776. Capellini, I., McNamara, P., Preston, B., Nunn, C., & Barton, R. (2009). Does sleep play a role in memory consolidation? A compara¬ tive test. PLoS ONE, 4. Harvey, P. H„ & Pagel, M. D. (1991). The com¬


Nunn, C., McNamara, P., Capellini, I., & Bar¬ ton, R. (2010). Primate sleep in comparative perspective. In C. Nunn, P. McNamara, & R. Barton (Eds.), Evolutionary and phylo¬ genetic perspectives on sleep (pp. 123-144). Cambridge: Cambridge University press. Preston, B.T., Capelleni, I., McNamara, P., Barton, R.A., & Nunn, C.L. (2009). Para¬ site resistance and the adaptive significance of sleep. BMC Evolutionary Biology, 9. Rattenborg, N.C., & Amlaner, C.J. (2010). A bird’s-eye view of the function of sleep. In P. McNamara, R. Barton, & C. Nunn (Eds.), Evolution of sleep: Phylogenetic and func¬ tional perspectives. Cambridge: Cambridge

University Press. Roth, T. C., Lesku, J.A., Amlaner, C.J., & Lima, S.L. (2006). A phylogenetic analysis of the correlates of sleep in birds. Journal of Sleep Research, 15, 395M02. Zepelin, H., & Rechtschaffen, A. (1974). Mammalian sleep, longevity, and energy metabolism. Brain Behavior and Evolution, 10, 425M70.

parative method in evolutionary biology.

Oxford: Oxford University Press. Lesku, J., Roth, T., Rattenborg, N., Amlaner, C., & Lima, S. (2009). History and future of comparative analyses in sleep research. Neuroscience and Biobehavioral Reviews, 33, 1024-1036.

Lesku, J.A., Roth II, T. C., Amlaner, C.J., & Lima, S.L. (2006). A phylogenetic analysis of sleep architecture in mammals: The intergration of anatomy, physiology, and ecol¬ ogy. The American Naturalist, 168, 1-13.

Phylogeny of Sleep Sleep and sleep-like rest have been de¬ scribed in several vertebrates and inverte¬ brates (Cirelli & Tononi, 2008; McNamara, Barton, & Nunn, 2010; Siegel, 2008). The evolution of sleep, however, has been studied mostly in mammals where data for several species are available. In placen¬

Martins, E. P. (Ed.). (1996). Phylogenies and

tal and marsupial mammals and in birds

the comparative method in animal behavior.

sleep is composed by two distinct neuro¬

New York: Oxford University Press.

physiological states, a rapid eye movement

McNamara, P., Barton, R., & Nunn, C. (2010). Evolution of sleep: Phylogenetic and func¬ tional perspectives. Cambridge: Cambridge

University Press. Nunn, C. L. (2011). The comparative approach

(REM) sleep, and a non-REM (NREM) sleep. During a sleep cycle, episodes of NREM sleep are followed by episodes of REM sleep, and several REM-NREM

in evolutionary anthropology and biology.

sleep cycles are repeated throughout

Chicago: University of Chicago Press.

a bout of sleep. Monotremes—echidna




Phylogeny of Sleep


or polyphasic when two or more sleep


bouts are alternated with bouts of activ¬

NREM sleep and some signs of REM

ity (Capellini et al., 2010; McNamara

sleep, while there is currently no convinc¬ ing evidence of REM-like sleep in reptiles

et al., 2008). This diversity in mammalian sleep pat¬

(McNamara, Nunn, Barton, Elarris, & Ca¬

terns is not randomly distributed with re¬

pellini, 2007). Therefore it is still unclear

spect to phylogeny. Conversely, closely

whether REM sleep evolved from a mixed

related species sharing recent common an¬

REM-NREM sleep state of early reptiles

cestors exhibit strong similarities in sleep

or it evolved independently in mammals

times (Capellini, Barton, McNamara, Pres¬

and birds. Aquatic mammals and birds can

ton, & Nunn, 2008a; see Figure 16).






also sleep unihemispherically, with uni-

Thus, like all biological traits, mam¬

hemispheric NREM sleep being obligatory

malian sleep patterns are shaped by the

only in cetaceans (Rattenborg, Amlaner, &

evolutionary history of the species—with

Lima, 2000).

closely related species being more similar


and birds

exhibit great

to one another than expected by chance—

variation in sleep patterns. This in¬

and natural selection. Natural selection

cludes differences among species in

promotes sleep because of its adaptive

the daily REM- and NREM-sleep dura¬

benefits but constrains time for sleep be¬

tions, REM-NREM sleep-cycle length,

cause of its ecological costs (Capellini

and in how sleep is accommodated in

et al., 2010). Ultimately, natural selec¬

the 24 hours (e.g., the number and du¬

tion leads to divergence in sleep patterns

ration of daily sleep bouts, the phasing

between species when these are under

of sleep). Mammalian total daily sleep

different selective pressures, but also de¬

time, as sum of REM- and NREM-sleep

termines convergence when analogous

durations, varies between 3 to 4 hours

selective pressures act on different spe¬

in ungulates and 20 hours in armadil¬

cies, leading to similar sleep patterns to

los (Chaetophractus villosus), with an REM-NREM sleep cycle ranging from

evolve independently in distantly related species.

6 minutes in the chinchilla (Chinchilla

Hypotheses on the benefits of sleep for

laniger) to 90 minutes in humans and

the brain are abundant, such as consolidat¬

chimpanzees {Pan troglodytes) (Cape¬

ing memories, promoting brain develop¬

llini, Preston, McNamara, Barton, &

ment, maintenance, or repair, but support

Nunn, 2010; McNamara, et al. 2008).

for these ideas is mixed (Siegel, 2001,

Unlike mammals, birds have very short

2005; Stickgold, 2005; Zepelin, Siegel, &

episodes of REM sleep, generally lasting

Tobler, 2005). Contrary to suggestions that

less than 10 seconds (Rattenborg & Am¬

a major function of NREM sleep in mam¬

laner, 2010). The phasing of sleep can

mals and birds is energy conservation, be¬

be monophasic when all sleep is consol¬

cause of their great energetic expenditure

idated into one daily bout, or biphasic

to maintain a high metabolic rate and body

Phylogeny of Sleep


Male ibex (Capra ibex) sleeping in Gran Paradiso National Park (Italy). Artiodactyls, like the ibex, sleep the least among all mammals. (Roberta Pedrotti)

temperature (Berger & Phillips, 1995), re¬

mammals that evolved longer sleep times

cent studies have found that species with

have higher immunity levels and lower in¬

higher energy requirements have the short¬

fection levels (Preston, Capellini, McNa¬

est—not the longest—sleep durations (Ca¬

mara, Barton, & Nunn, 2009).

pellini et ah, 2008a; Lesku, Roth, Amlaner,

Beyond parasites, other ecological fac¬

& Lima, 2006). Indeed the amount of energy

tors influence sleep evolution. Sleeping

saved during sleep appears to be negligible

individuals are more vulnerable to preda¬

(Stahel, Megirian, & Nicol, 1984). There

tion because sleep is accompanied by re¬

is instead growing evidence that sleep pro¬

duced responsiveness to external stimuli

motes immunocompetence. Not only does

(Lima, Rattenborg, Lesku, & Amlaner,

sleep facilitate an immune response in in¬

2005). High predation risk promotes the

dividuals challenged by parasitic infections

evolution of short sleep durations in mam¬

(Bryant, Trinder, & Curtis, 2004), but also

mals and birds; thus species that sleep in


Total daily sleep duration (hrs) NREM sleep REM sleep

Erinaceus europaeus

Eutamias sibiricus Spermophilus lateralis Spermophilus tridicemlineatus Spermophilus parryi

Phodopus sungorus Dicrostonyx torquatus Neotomodon alstoni -



a-~r~ ezz LI




- ! ..

-r——r Siqmodon hispidus

~~r. Bradypus tridactylus


Dasypus novemcinctus Chaetophractus villosus Priodontes maximus

Tenrec ecaudatus Didelphis marsupialis Lutreolina crassicaudata Trichosurus vulpecola Potorous tridactylus

Figure 16: Closely related species sharing a more recent common ancestor exhibit more similar sleep times than more distantly related species. Thus, sleep durations are not randomly distributed with respect to phytogeny. For example, all macaques (genus Macaca) sleep for about 8 to 9 hours a day, with approximately 1 hour REM sleep, while more distantly related primates, such as lemurs, sleep 10 to 15 hours a day (From McNamara et al. [2010], Reprinted with permission.)

Phylogeny of Sleep


forage frequently in small mammals, char¬ acterized by relatively high energetic re¬ quirements for their size and limited fat reserves, might also be responsible for the evolution of polyphasic sleep and short REM-NREM sleep cycles in these species (Capellini et al., 2008b). There¬ fore polyphasic sleep is mostly found in small mammals, while monophasic sleep evolved in association with a medium to large body size (see Figure 17; Capellini et al., 2008b). Body size is instead unre¬ lated to sleep durations in both mammals and birds (Capellini et al., 2008a; Lesku et al., 2006; Roth et al., 2006). Finally, the distribution of resources in the en¬ vironment can potentially influence the Red panda (Ailurus fulgens) sleeping on a bam¬ boo roof in a Paris zoo. Red pandas are solitary

evolution of sleep. For example, when food resources and sleeping sites are dis¬

and are active during the night, dawn, and dusk.

tant from one another, monophasic sleep

Their sleep pattern has not been studied yet. (Isa¬

and shorter sleep durations should evolve

bella Capellini)

to save time for traveling between sites (Acerbi, McNamara, & Nunn, 2008).

exposed sites, such as the ground in open

Whether shorter sleep times are evolu¬

grassland, sleep less than species that sleep

tionary compensated by increases in sleep

in protected sites, such as tree holes or dens

intensity is still an open question. However,

(Capellini et al., 2008a; Lesku et al., 2006;

monophasic sleep, characterized by longer

Roth, Lesku, Amlaner, & Lima, 2006).

sleep cycles, might deliver the benefits

However, predation risk does not explain

of sleep more efficiently than polyphasic

species differences in phasing of sleep and

sleep with its shorter sleep cycles (Ca¬

REM-NREM sleep-cycle length (Capel¬

pellini et al., 2008b). Longer sleep cycles

lini, Nunn, McNamara, Preston, & Barton,

probably reduce the total daily sleep time

2008b). Because time for sleep is detracted

because they limit the total time in tran¬

to other important activities, such as rear¬

sitional sleep stages needed to enter deep

ing offspring, sleep should be associated

NREM sleep (see Figure 18). Indeed, mono¬

with opportunity costs. Mammals that

phasic sleep, which evolved from polypha¬

need to spend much time foraging, such

sic sleep (see Figure 17), is associated with

as those with high energetic requirements

shorter sleep durations, and might represent

or herbivorous diet, or social species that

an evolutionary advantage of larger-bodied

need time for social interactions, sleep less

species (Capellini et al., 2008b).

(Capellini et al., 2008a). The necessity to

Isabella Capellini


Giraffa Camelopardalis Bos taurus Ovis aries Sus scrofa Equus asinus Equus caballus Mustela putorius furo Canis familiaris Vulpes vulpes Panthera tigris Felis catus Erinaceus eropaeus Condylura cristata Scalopus aquaticus Mus musculus Rattus norvegicus Meriones unguiculatus Mesocricetus auratus Phodpus sungorus Cricetomys gambianus Nannospatax ehrenbergi Octodon degus Chinchilla lanigera Cavia porcellus Aplodontia rufa Eutamias sibiricus Tamias striatus Spermophilus lateralis Spermophilus tridicemlineatus Spermophilus parryi Spermophilus undulatus Oryctolagus cuniculus Tupaia glis Petterus macaco Microcebus murinus Callithrix jacchus Saimiri sciureus Aotus trivirgatus Macaca mulatta Macaca arctoides Macaca nemestrina Papio anubis Papio papio Theropithecus gelada Pan troglodytes Bradypus tridactylus Choloepus hoffmanni Dasypus novemcintus Heterohyrax brucei Procavia johnstoni Elephas maximus Loxodonta africana Potorous tridactylus Didelphis marsupialis Tachyglossus aculeatus Ornithorhynchus anatinus

Figure 17: Evolutionary History of Phasing of Sleep (Maximum Likelihood Reconstruction). Polyphasic sleep (black) is strongly supported as the ancestral character state in mammals, while monophasic sleep (white) has independently evolved multiple times in medium- and large-bodied mammals. (From McNamara et al. [2010]. Reprinted with permission.)

Phylogeny of Sleep


Total sleep





Figure 18: Longer Sleep Cycles Require Less Time in Transitional Sleep Stages, Ultimately Leading to a Reduction in Total Daily Sleep Time. In (a) a hypothetical species sleeping nine units of time in deep sleep (darker shade), needs 3 units of time in transitional sleep (one per unit of deep sleep; lighter shade) when the total deep sleep is partitioned in three blocks; this leads to a total of 12 units of sleep. Conversely, in (b) only 1 unit of time in transitional sleep is needed if all the deep sleep is consolidated into one block, leading to a total of 10 units of sleep. Thus monophasic sleep, that is associated with longer sleep cycles and shorter daily sleep time, might deliver the benefits of sleep more efficiently than polyphasic sleep. (Redrawn from Capellini et al. [2010]. Reprinted with permission.)

References Acerbi, A., McNamara, P., & Nunn, C.L. (2008). To sleep or not to sleep: The ecol¬ ogy of sleep in artificial organisms. BMC Evolutionary Biology, 8, 10. Berger, R.J., & Phillips, N. H. (1995). Energy conservation and sleep. Behavioral Brain Research, 69, 65-73. Bryant, P.A., Trinder, J., & Curtis, N. (2004). Sick and tired: Does sleep have a vital role in the immune system? Nature Reviews Im¬ munology, 4, 457-467. Capellini, I., Barton, R. A., McNamara, P., Preston, B.T., & Nunn, C.L. (2008a). Phy¬ logenetic analysis of the ecology and evo¬ lution of mammalian sleep. Evolution, 62, 1764-1776. Capellini, I., Nunn, C.L., McNamara, P., Pres¬ ton, B.T., & Barton, R.A. (2008b). Ener¬ getic constraints, not predation, influence the evolution of sleep patterning in mam¬ mals. Functional Ecology, 22, 847-853. Capellini, I., Preston, B.T., McNamara, P., Barton, R. A., & Nunn, C.L. (2010). Eco¬ logical constraints on mammalian sleep ar¬ chitecture. In P. McNamara, R. A. Barton, & C.L. Nunn (Eds.), Phylogeny of sleep

(pp. 12-33). Cambridge: Cambridge Uni¬ versity Press. Cirelli, C., & Tononi, G. (2008). Is sleep essen¬ tial? PLoS Biology, 6, 1605-1611. Lesku, J.A., Roth, T. C., Amlaner, C.J., & Lima, S.L. (2006). A phylogenetic analysis of sleep architecture in mammals: The in¬ tegration of anatomy, physiology and ecol¬ ogy. American Naturalist, 168, 441^153. Lima, S.L., Rattenborg, N.C., Lesku, J.A., & Amlaner, C.J. (2005). Sleeping under the risk of predation. Animal Behaviour, 70, 723-736. McNamara, P., Barton, R.A., & Nunn, C.L. (Eds). (2010). Evolution of sleep. Cam¬ bridge: Cambridge University Press. McNamara, P., Capellini, I., Harris, E., Nunn, C.L., Barton, R.A., & Preston, B. (2008). The phylogeny of sleep database: A new re¬ source for sleep scientists. The Open Sleep Journal, 1, 11-14. McNamara, P., Nunn, C. L., Barton, R. A., Har¬ ris, E., & Capellini, I. (2007). Phylogeny of sleep and dreams. In D. Barrett & P. McNa¬ mara (Eds.), The new science of dreaming: Biological aspects (pp. 12-22). Westport, CT: Praeger.




Phylogeny of Sleep Database

Preston, B.T., Capellini, I., McNamara, P., Barton, R. A, & Nunn, C.L. (2009). Para¬ site resistance and the adaptive significance of sleep. BMC Evolutionary Biology, 9, 7. Rattenborg, C.N., & Amlaner, C.J. (2010). A bird’s-eye view of the function of sleep. In P. McNamara, R.A. Barton, & C.L. Nunn (Eds.), Phylogeny of sleep (pp. 145-171). Cambridge: Cambridge University Press. Rattenborg, C. N., Amlaner, C. J., & Lima, S. L. (2000). Behavioral, neurophysiological and evolutionary perspectives on unihemispheric sleep. Neuroscience and Biobehavioral Reviews, 24, 817-842. Roth, T. C., Lesku, J. A., Amlaner, C.J., & Lima, S.L. (2006). A phylogenetic analysis of the correlates of sleep in birds. Journal of Sleep Research, 15, 395^102.

data on sleep expression in as many species as possible. Early comparative databases on sleep durations in mammals contained only about 40 or so species and the quality of some of the data points was question¬ able. The largest database on comparative sleep patterns constructed to date is prob¬ ably the database housed at Boston Uni¬ versity and known as “The phylogeny of sleep” database. It is accessible online at www.bu.edu/phylogeny. This Web site provides background on the database it¬ self, hypotheses regarding the evolution of sleep expression and functions, details on how the database was constructed, and a portal to search the latest version of the

Siegel, J.M. (2001). The REM-sleep mem¬ ory-consolidation hypothesis. Science, 294, 1058-1063.

database. If the database is ever transferred

Siegel, J.M. (2005). Clues to the function of mammalian sleep. Nature, 437, 1264-1271.

will be provided.

Siegel, J.M. (2008). Do all animals sleep? Trends in neuroscience, 31, 208-213.

Sleep database was constructed with sup¬

Stahel, C.D., Megirian, D., & Nicol, S.C. (1984). Sleep and metabolic rate in the lit¬ tle penguin (Eudyptula minor). Journal of

from Boston University to some other lo¬ cation, forwarding links and information The current version of the Phylogeny of port from the National Institute of Mental health and contains sleep quotas retrieved from 178 separate literature references rep¬

Comparative Physiology B: Biochemical,

resenting 130 different mammalian species

Systemic and Environmental Physiology,

in 50 families and 17 orders. Sleep quotas

154, 487-494.

refer to sleep durations of the two major

Stickgold, R. (2005). Sleep-dependent memory consolidation. Nature, 437, 1272-1278.

phases of mammalian sleep: rapid eye

Zepelin. H., Siegel, J.M., & Tobler, I. (2005). Mammalian sleep. In M.H. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practices of sleep medicine. New York: Saunders.

In addition to containing data on sleep

movement or REM sleep and non-REM sleep. for the largest number of species ever as¬ sembled the data in the database are also scored for quality. Previous comparative datasets did not score their data for qual¬

Phylogeny of Sleep Database

ity indices, such as whether the data were collected from restrained animals, the du¬

One way to study potential functions of

ration of recording, or the availability of

sleep as well as the evolutionary history of

food and water during observations. These

sleep is to construct databases that contain

experimental procedures likely impact the

Phylogeny of Sleep Database


estimates of REM- and NREM-sleep dura¬

fur seals) and Phocidae (true seals), show

tions as studies of selected species’ sleep

both unihemispheric and bihemispheric

in the wild versus in the lab have shown.

forms of sleep. Phocids sleep under water

Luckily most studies of sleep expression

(obviously holding their breath), and both

in animals published since 1953—the year

hemispheres exhibit either REM or SWS.

REM was discovered—did in fact provide

Amazonian Manatees (Trichechus inun¬

detailed descriptions of the methods under

guis) also sleep while under water exhibit¬

which sleep data were gathered.

ing three sleep states: bihemispheric REM,

Data for the Phylogeny of Sleep database

bihemispheric SWS, and unihemispheric

were obtained from previous data compi¬

SWS. Both hemispheres awaken to sur¬

lations, as well as an exhaustive literature

face and breathe. A further complication

search dating back to 1953, to gather new

of sleep expression in these animals is that

data. Key terms used in literature searches

some facultatively adjust their sleep pat¬

were REM, NREM, sleep architecture,

terns when sleeping on land. Thus to fully

EEG, and total sleep time. Searches were

capture daily sleep quotas in these animals

conducted within bibliographic databases

one would want to record sleep times for

that cover publications in English, French,

both REM and NREM in both the right and

Russian, German, and Spanish. Whenever

left hemispheres on land and in the water.

possible, investigators recorded the sex

With respect to assessing and improv¬

and age of the individual animals whose

ing data quality in the Phylogeny of Sleep

sleep was measured, breaking down male

database, information was extracted on

and female values when possible.

the following laboratory conditions and

Although data on sleep of aquatic mam¬

experimental procedures from the original

mals are included in the database, extreme


caution should be used when analyzing this

Recording method (EEG). Whether sleep

data until a consensus emerges among ex¬

duration estimates were based on EEG re¬

perts on sleep in these animals as to how

cordings or not.

best to summarize sleep expression in

Telemetry (yes or no). Whether sleep dura¬

these animals. Members of three different

tion estimates were based on telemetric re¬

orders that contain aquatic mammals—

cordings in the wild.





egorical three-state variable). Studies were

whales), carnivores (seals, sea lions, and

assigned to one of three categories: ■ / v

r3 . Ts


Ts * 01 *

' **

M f 1 ’ V'“vV\ / H v« V Asf'V/S.^' \''"V“k'. V',‘V','W,VAN


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o m

OtD nnm nryniin

EDO an a omo

iiiiiii i


iiiiiniii i

mm u t

lit tit


tin mrmn


□ □

in »t 111 t

□ mo








inm aumnDO □



□ DO


fl ir nn i


1 III! ii iiidlil i ii ulitt 1


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to OO 0



0B3 iron





Unihemispheric sleep in a bottlenose dolphin. Top row: Electroencephalogram (EEG) of the right (R) and left (L) cortical hemispheres during waking (A), right (B) and left (L) hemispheric slow-wave sleep. Middle row: Slow-wave activity (SWA, EEG power in the range of 1.2-4.0 Hz, 30 sec epochs) in the two hemispheres recorded over a period of 2 hours and 20 minutes showing episodes of unihemispheric sleep in the right and left hemispheres. EEG power was normalized as a percentage of the maximum power in each hemisphere during this period. Letters a, b, and c mark the time of polygrams expanded in the top row. Bottom row: The state of each dolphin eye (R, right; L, left) over the same period scored in real time (O, open; I, intermediate; or C, closed) and then categorized for 30-second epochs. Each mark represents one epoch. (Oleg Lyamin)

eye directed toward the mother is open

is open or in an intermediate state (95%

more often than the eye directed to the

to 98% of the observation time), while

opposite direction, suggesting that calves

the eye contralateral to the sleeping hemi¬

continue to maintain visual contact with

sphere was largely closed (40% to 60%). In

their mothers during sleep (Lyamin et al.,

contrast to terrestrial mammals, both eyes

2007). Studies on belugas and bottlenose

were rarely noted to be closed in dolphins

dolphins revealed that during USWS, the

and belugas (less than 2.0% of the observa¬

eye contralateral to the waking hemisphere

tion time). All these data provide support




Sleep in Aquatic Mammals

for the hypothesis that USWS in cetaceans

southern sea lion), five true seals (the gray

serves a sentinel function, specifically

seal, Caspian seal, harp seal, northern el¬

to scan at least half the environment for

ephant seal, harbor seal), and in the only

predators and to maintain coherence of the

leaving species of walruses.

group while asleep (Lyamin et al., 2004, 2008c).

Among the eared seals (fur seals and sea lions, the Otariidae family), sleep has been

The need to come to the surface to breathe

most extensively studied in the northern

is an obvious life sustaining requirement

fur seal (e.g., Lyamin et al., 2008b; Ly¬

for any aquatic mammal. Small-sized ce¬

amin & Mukhametov, 1998). When on

taceans (e.g., the harbor porpoise) main¬

land, fur seals predominately display bi¬

tain regular breathing when continuously

lateral SWS and REM sleep in the range

swimming and being asleep with respira¬

of normal variations. Both are typical for

tory pauses that rarely exceed 60 seconds

all terrestrial mammals. At the same time

in duration. Respiratory acts in dolphins

fur seals exhibit SWS with greatly ex¬

are fully compatible with uninterrupted

pressed interhemispheric EEG asymmetry

USWS; that is, they do not necessarily

(also called asymmetrical SWS), which re¬

cause arousal and behavioral awakening

sembles USWS in cetaceans. The propor¬

(Lyamin et al., 2008c). Larger cetaceans

tion of asymmetrical SWS while on land is

(e.g., the beluga) display long apneas (lon¬

minimal in 10- to 20-day-old fur seal pups

ger than 10 minutes) during sleep while

(on average 5% of the total SWS time) and

floating at the surface and submerging to

maximal in juveniles (45%). The degree

depth. It is known that barbiturates induce

of EEG asymmetry in fur seals greatly in¬

bilateral high-voltage SWS in dolphins,

creases when they sleep in water. At the

which immediately caused a cessation of

same time the amount of REM sleep sub¬

breathing. Diazepam (or valium) depend¬

stantially decreases (up to 90% of REM

ing on the dose induces either USWS or

sleep on land) and can be virtually absent

high-voltage bilateral SWS without a ces¬

for a period of one to two weeks. Another

sation of breathing. However, immedi¬

remarkable feature is striking motor asym¬

ately prior to each respiration the EEG

metry in fur seals when they are sleeping

amplitude in one or in both hemispheres

in water. They sleep at the surface on their

drops, so that dolphins enter the state of

sides, paddling with one foreflipper, while

either USWS or waking (Mukhametov &

holding the three other above the surface.

Polyakova, 1981). These data are con¬

The paddling flipper is always contralateral

sidered to support the idea that USWS is

to the waking hemisphere. This behavior

necessary for autonomic breathing in ceta¬

and sleep posture prevents heat loss while

ceans (Mukhametov, 1984).

fur seals are asleep in water. The last but

In contrast to fully aquatic cetaceans,

not the least is that fur seals can sleep with

pinnipeds live both on land and water. To

only one eye closed while the other eye

date, sleep has been examined in 10 species

briefly opens. Similar to that in dolphins,

of pinnipeds: four eared seals (the northern

the open eye is always contralateral to the

fur seal, Cape fur seal, Steller’s sea lion,

waking hemisphere while the closed eye

Sleep in Aquatic Mammals


is contralateral to the sleeping hemisphere.

Lyamin, Oleksenko, & Polyakova, 1993;

The association between USWS, motion,

Mukhametov, Supin, & Polyakova, 1984).

and brief opening of one eye suggests that

The majority of SWS recorded in the

USWS in fur seals serves (1) to maintain

only electrophysiologically examined wal¬

vigilance to detect predators and conspe-

rus was scored as bilateral SWS. When in

cifics as well as (2) to sustain motion and

water, sleep occurred while the walrus was

sleep posture to optimize thermoregula¬

floating motionless at the surface or lying

tion while asleep (Lyamin et al., 2004). As

on the bottom of the pool. Episodes of

in terrestrial mammals, the breathing pat¬

asymmetrical SWS were occasionally re¬

tern of fur seals during SWS is regular. In

corded both on land and in water and corre¬

REM sleep, breathing becomes irregular

lated with a brief one eye opening as in fur

but apneas rarely last longer than 30 sec¬

seals (Lyamin et al., 2008a). A behavioral

onds. The studies in other otariids revealed

study also revealed that walruses occa¬

largely a similar sleep pattern and sleep be¬

sionally become almost continuously ac¬

haviors as described for the northern fur

tive (80% to 99% of the time) for a period

seal (Pryaslova et al., 2009).

of three to four days which was followed

Regardless of if true seals (the Phocidae

by extended periods of rest lasting up to

family) sleep on land or in water, SWS in

19 hours. The breathing pattern in walruses

these animals is always bilateral, as in ter¬

was regular during quiet wakefulness and

restrial mammals. Individual REM-sleep

SWS while on land as in fur seals and it

episodes in phocids are shorter then in

was interrupted while in water with alter¬

otariids. They usually occur in series fol¬

nating apneas and ventilations as in eared

lowing SWS. In contrary to dolphins and

seals (Pryaslova et al., 2009). Therefore,

fur seals, there are no reports of asymmet¬

the pattern of sleep in the walrus appears

rical eye opening in sleeping true seals.

to be linked to the need to sleep while sub¬

Phocids can hold their breath for doz¬

merged as it is in phocids.

ens of minutes (in some species for one

In conclusion, the need to come to the

hour) while asleep. During SWS, sleep

surface to breathe, more efficient monitor¬

apneas alternate with periods of fast regu¬

ing of the environment, and thermogenesis

lar breathing. During REM sleep, breath¬

appear to be the main factors that have led

ing becomes sporadic and many episodes

to the evolution of the present sleep phe¬

occur within a single apnea. The sleep

nomenology in aquatic mammals. Sleep in

of phocids in water is also accompanied

water while in motion (cetaceans, fur seals)

by complete immobility but they usu¬

is one strategy. At these times sleep devel¬

ally wake up when surfacing to breathe.

ops unihemispherically, and it is USWS

Many phocids live in cold freezing seas

that allows motion (muscle thermogenesis

with limited access to the open water.

and postural thermoregulation) and asym¬

The ability to sleep during apneas mini¬

metrical eye opening (monitoring of the en¬

mizes time spent at the water surface. It

vironment). The second strategy of sleep in

is seen as a vital adaptive feature of the

water is to become apneac diving for sleep

phocid sleep (e.g., Castellini et al., 1994;

(bilateral SWS and REM) to depth or under




Sleep in Children with Cancer

ice (true seals and walruses), which would

Pinnipeds. Italian Archives of Biology, 142,

be the only way to survive in freezing seas


as well as an efficient retreat from poten¬ tial predators. At the same time, the neuro¬ physiological mechanisms underlying the described aquatic mammal sleep phenom¬ enology are largely unknown. Oleg Lyamin

See also: entries related to Evolution of Sleep References Castellini, M. A., Milsom, W. K., Berger, R.J., et al. (1994). Patterns of respiration and heart rate during wakefulness and sleep in elephant seal pups. American Journal of Physiology, 266, R863-R869. Goley, P. D. (1999). Behavioral aspects of sleep in pacific white-sided dolphins (Lagenorhynchus obliquidens, Gill 1865). Marine Mammal Science, 15, 1054-1064. Lilly, J.C. (1964). Animals in aquatic envi¬ ronments: Adaptations of mammals to the ocean. In D. B. Dill (Ed.), Handbook of phys¬ iology—environment (pp. 741-747). Wash¬ ington, DC: American Physiology Society. Lyamin, O., Kosenko, P., Lapierre, J., et al. (2008c). Study of sleep in a walrus. Sleep, 31, A24. Lyamin, O. I., Lapierre, J.L., Kosenko, O.P., et al. (2008b). EEG asymmetry and spectral power in the fur seal. Journal of Sleep Re¬ search, 17, 154-165. Lyamin, O.I., Manger, P. R., Ridgway, S.H., et al. (2008a). Cetacean sleep: An unusual form of mammalian sleep. Neuroscience and Biobehavioral Review, 32, 1451-1484. Lyamin, O.I., & Mukhametov, L. M. (1998). Organization of sleep in the northern fur seal. In V.E. Sokolov, A. A. Aristov, & T. U. Lisitzina (Eds.), The northern fur seal: Systematic, morphology, ecology, behavior

Lyamin, O.I., Oleksenko, A. I., & Polyakova, I. G. (1993). Sleep in the harp seal (Pagophilus groenladnica). Peculiarities of sleep in pups during the first month of their lives. Journal of Sleep Research, 2, 163-169. Lyamin, O.I., Pryaslova, J., Kosenko, P.O., et al. (2007). Behavioral aspects of sleep in bottlenose dolphin mothers and their calves. Physiology and Behavior, 92, 725-733. Lyamin, O. I., Pryaslova, J., Lance, V., et al. (2005). Animal behaviour: Continuous ac¬ tivity in cetaceans after birth. Nature, 435, 1177. Lyamin, O.I., Shpak, O.V., Nazarenko, E. A., et al. (2002). Muscle jerks during behavioral sleep in a beluga whale (Delphinapterus leucas L.). Physiology and Behavior, 76, 265-270. Mukhametov, L. M. (1984). Sleep in marine mammals. Experimental Brain Research, 8, 227-238. Mukhametov, L.M., & Polyakova, I.G. (1981). EEG investigation of sleep in por¬ poises (Phocoena phocoena). Journal of High Nerve Activity, 31, 333-339. Mukhametov, L.M., Supin, A., & Polyakova, I. G. (1977). Interhemispheric asymmetry of the electroencephalographic sleep pattern in dolphins. Brain Research, 134, 581-584. Mukhametov, L. M., Supin, A., & Polyakova, I.G. (1984). Sleep in Caspian seals (Phoca caspica). Journal of High Nerve Activity, 34, 259-264. Pryaslova, J.P., Lyamin, O.I., & Siegel, J.M., et al. (2009). Behavioral sleep in the walrus. Behavioral Brain Research, 19, 80-87.

Sleep in Children with Cancer

(pp. 280-302), Moscow: Nauka. Lyamin, O.I., Mukhametov, L.M., & Siegel, J.M. (2004). Association between EEG asymmetry and eye state in Cetaceans and

Sleep is a fundamental biological process necessary for life and well-being that is woven into the fabric of our lives. Cancer

Sleep in Children with Cancer


disrupts this process. Cancer occurs in

respiratory control center and lead to sleep

about 15 per 100,000 children (Reis et al.,

disordered breathing. Injury to the hypo¬

2005). The most common childhood can¬

thalamus, thalamus, and brain stem may re¬

cers are leukemia and brain tumors, ac¬

sult in excessive daytime sleepiness (EDS).

counting for 27 and 22 percent of all

Brain trauma resulting in seizures may lead to sleep fragmentation causing EDS and un¬

childhood cancers. At present the overall survival rate for all childhood malignan¬ cies is 79 percent, which has led to a large

usual nocturnal awakenings. 2. Side effects of chemotherapy—dexamethasone in adolescent and young adults—often

population of children and young adults

leads to insomnia; in preadolescents dexa-

who are cancer survivors. However, neu¬

methasone may result in EDS (Hinds et al.,

rosurgery and the toxic therapies used to


successfully treat cancer result in a great

3. Fatigue






deal of collateral damage, which together

and children with cancer (Ancoli-Israel,

are termed late effects, present in up to

Moore, & Jones, 2001). Fatigue often leads

75 percent of childhood cancer survivors.

to daytime napping and decreased daytime

Sleep problems are one of the least well-

activity, which in turn may disrupt the cir¬

recognized late effects of cancer treatment.

cadian sleep/wake rhythm causing both in¬ somnia and EDS.

The unique causes of sleep problems

4. Radiation therapy—radiation hypersomnia

seen in children with cancer relate to:

is seen in 60 percent of children treated with

1. Central nervous system (CNS) injury caused

>2400 cGray of CRT and typically appears

by brain tumors, neurosurgical procedures,

3 to 14 days after treatment. Though usu¬

or cranial radiation therapy (CRT). Injury

ally transient, increase in total sleep time

to the medulla oblongata may damage the

and persistent EDS are described in some

Table 6: Children with Cancer Seen in Sleep Clinic Children with cancer seen

Total # EDS/long N=






70% of total

42/70 (60%)

28/70 (40%)

17/70 (24%)

3/70 (4%)

6/70 (9%)









5/35 (14%)



Posterior fossa















6/18 (33%)





4/18 (22%)










in sleep clinic 1994-2009 Total

Tumors of central


nervous system Hypothalamus/brainstem

Leukemia/other blood Other solid tumors




Sleep in Children with Cancer

Table 7: Treatments of Sleep Problems in Children with Cancer (children may have more than one problem) Sleep problems


Parasomnia N = 6 Seizures Confusional arousals Sleep eating Sleep disordered breathing N = 28 OSA At = 20

CSA A = 6

Hypoxia N = 2 EDS/long sleeper At = 42




Clonazepam—1 Sleep extension/ sleep hygiene—1








T&A No treatment (Al < 5) BIPAP + rate + 02 Tracheotomy + ventilator


7 1 1 1 2 1

Diaphramatic pacers



42 17 6 4 4 1 1 1

No treatment Anticonvulsants

Sleep hygiene and extension Methylphenidate Modafanil Amphetamine salts Declined stimulants Treatment of drug abuse CPAP anticonvulsants

Insomnia At = 17


Sleep hygiene and sleep restriction

3 3

Pain control Sedative hypnotics





Melatonin + sleep hygiene

DSPS Irregular sleep/wake

1 1

Melatonin + sleep hygiene

Circadian rhythm At = 3

Sleep hygiene

T&A—tonsillectomy and adenoidectomy; OSA—obstructive sleep apnea; CSA—central sleep apnea; CPAP—continuous positive airway pressure; BIPAP—bilevel positive airway pressure; Al—apnea index; DSPS—delayed sleep-phase syndrome

individuals, though the mechanism is not understood. 5. Pain is common in children with cancer and often leads to sleep disruption.

6. Stress, anxiety, depression, posttraumatic stress disorder are all commonly described in children with cancer (Langeveld et al., 2004) and sleep problems, particularly

Sleep in Children with Cancer


insomnia, nightmares, and EDS may be sec¬

circadian-rhythm disorders) and are often

ondary symptoms of these conditions.

present in combinations. Children with can¬

7. Twenty-seven percent of cancer survivors

cers involving the CNS, particularly brain

have severe or life-threatening medical

stem, thalamus, and hypothalamus were

late effects, and 45 percent will have some chronic medical problems as a direct result of their cancer treatment (Oeffinger et al., 2006). Endocrine deficiencies of thyroid, cortisol, growth hormone, and vasopres¬

the most frequently referred for sleep eval¬ uation and the most commonly seen sleep problems were EDS and sleep disordered breathing. The unusual distribution of the

sin are common after CRT and may impact

types of cancers and types of sleep prob¬

on sleep. Cardiorespiratory, gastrointes¬

lems seen in this referral population may be

tinal, neurological, and musculoskeletal

the result of two factors. Children with can¬

later effects are all common after cancer

cer are likely to have the same background

treatment and all may affect sleep (see

prevalence of the common sleep disorders

Table 6).

seen in any child; and CNS-directed thera¬ pies affecting areas of the brain most im¬

The largest review of sleep problems in

portant in sleep/wake regulation, the brain

children with cancer is a 15-year retrospec¬

stem, thalamus, and hypothalamus are

tive case series of children referred for a

more likely to lead to EDS, obstructive

comprehensive sleep evaluation (Rosen &

sleep apnea, and central sleep apnea.

Brand, 2010). Though there is obvious re¬

Gerald Rosen

ferral bias in this population, it does allow for the characterization of the sleep prob¬ lems in children with cancer. The sleep

See also: entries related to Sleep and Develop¬ ment; entries related to Sleep Disorders

problems and types of cancers are described


in the first table; the treatment is described

Ancoli-Israel, A., Moore, P., & Jones, V. (2001). The relationship between fatigue and sleep in cancer patients: A review. Eu¬ ropean Journal of Cancer, 10, 245-255.

in the second table. Sixty-eight percent of the children with cancer referred for sleep evaluation had brain tumors. Tumors in¬ volving the thalamus, hypothalamus, and brain stem accounted for 50 percent of the referrals, though this group of tumors com¬ prises only 15 percent of all pediatric malig¬ nancies. The most common sleep problems found in these children with cancer were EDS/long sleepers seen in 60 percent of the children and sleep apnea in 40 percent. Both of these problems were successfully treated once they were recognized (see Table 7). The sleep problems of children with

Hinds, P., Hockenberry, M., Gattuso, J., et al. (2007). Dexamethasone alters sleep and fa¬ tigue in pediatric patients with acute lympho¬ blastic leukemia. Cancer, 110, 2321-2330. Langeveld, N., Grootenhuis, M., Voute, P., et al. (2004). Posttraumatic stress symptoms in adult survivors of childhood cancer. Pedi¬ atric Blood Cancer, 42, 604-610. Oeffinger, K., Mertens, A., Sklar, C., et al. (2006). Chronic health conditions in adult survivors of childhood cancer. New England Journal of Medicine, 355(15), 1572-1582. Reis, L., Eisner, M., Kosary, C., et al. (2005).

cancer span the full spectrum of clini¬


cal sleep disorders (EDS, insomnia, sleep

2002. Bethesda, MD:

disordered breathing, parasomnias, and


cancer statistics



National Cancer




Sleep in Disorders of Consciousness

Rosen, G., & Brand, S. (2010). Sleep in chil¬ dren with cancer: Case review of 70 chil¬ dren evaluated in a comprehensive pediatric sleep center. Support Care Cancer, DOI 10.1007/S00520-010-0921.

for BIPs, as sleep deprivation is known to have major and devastating impacts on immune functioning. And probably most alarming, sleep disruptions can induce sympathetic activation and elevation of blood pressure, which can contribute to

Sleep in Disorders of Consciousness

the patient’s morbidity. In summary, little is known about the sleep experienced by BIPs and careful

While it is well known that abnormalities

examination of sleep in disorders of con¬

of sleep are extremely common in criti¬

sciousness, including circadian regula¬

cally ill patients (for review see Parthasara-

tion is warranted. Guidelines on how to

thy & Tobin, 2004); mechanisms are still

improve sleep in these patients are thus

poorly understood and fine-grained anal¬

needed (e.g., curtailing unnecessary vis¬

yses are missing (for review see Cologan

its by hospital personnel during habitual

et al., 2010). In brain-injured patients

sleep times or reduce noise and introduce

(BIPs) about half of total sleep time occurs

ambient light levels), might support bet¬

during the day time, andcircadian rhy thmic-

ter recovery and might intercept complica¬

ity is markedly diminished or even lost. In

tions that are related to weakened immune

addition to sleep, the biological clock reg¬

system functioning due to insufficient

ulates several physiological, behavioral,

amounts of restful sleep.

and biochemical rhythms. However, poly¬

Additionally, EEG patterns resembling

graphic recordings are needed to reliably

sleep have been considered as favorable

measure sleep quantity, quality, as well as

prognostic markers for long (e.g., Ber-

circadian regulation in BIPs. Patients ex¬

gamasco, Bergamini, Doriguzzi, & Fabi-

hibit more frequent arousals and awaken¬

ani, 1968) and it has been reported that

ings than normal, and decreases in REM

sleep patterns continue to improve during

and slow-wave sleep are common (e.g.,

rehabilitation together with the recovery of

Freedman, Gazendam, Levan, Pack, &

cognitive functions (Ron, Algom, Hary, &

Schwab, 2001). Note that the degree of

Cohen, 1980). In a study by Evans and

sleep fragmentation is at least equivalent

Bartlett (1995), it was shown that sleep¬

to that seen in patients with obstructive

like traces with K-complexes in response

sleep apnoea. However, causes for sleep

to stimulation are indicative of a good out¬

problems in BIPs are generally unknown

come, whereas traces with no spontaneous

although severity of the underlying dis¬

arousal activity were indicative of death or

ease is likely to be an important factor.

vegetative state. A more recent study by

Further factors contributing to sleep ab¬

Valente and colleagues (2002) compared

normalities in BIPs include acute illness,

the predictivity of different levels of sleep-

pain, discomfort, and increased alert¬

wake organization with other possible

ness induced by continuous exposure to

prognostic indexes such as neuroradiolog-

light. This is probably especially critical

ical findings, age, or Glasgow coma scale

Sleep in Insects

scores. In this study based on 24 hours of polysomnographic recordings, the authors report that the presence of organized sleep patterns is highly predictive for good out¬ come. Especially NREM-sleep elements such as K-complexes and sleep spindles as well as REM-sleep elements alternating with NREM-sleep elements were related to good recovery. It is concluded that polysomnography might carry considerable information about the ability of BIPs to recover by reflecting


Parthasarathy, S., & Tobin, M. J. (2004). Sleep in the intensive care unit. Intensive Care Medicine, 30(2), 197-206. Ron, S., Algom, D., Hary, D., & Cohen, M. (1980). Time-related changes in the distri¬ bution of sleep stages in brain injured pa¬ tients. Electroencephalography & Clinical Neurophysiology, 48(4), 432^441. Valente, M., Placidi, F., Oliveira, A. J., Bigagli, A., Morghen, I., Proietti, R., et al. (2002). Sleep organization pattern as a prognos¬ tic marker at the subacute stage of posttraumatic coma. Clinical Neurophysiology, 113(11), 1798-1805.

the residual integrity of the central nervous system and functionality of the brain (for review see Cologan et al., 2010). Yet the

Sleep in Insects

major challenge when studying sleep in critically ill patients remains; that is, scor¬

The origins and functions of sleep are on¬

ing sleep in extremely altered and slowed

going biological mysteries. Did the first

EEG traces.

primitive organisms that occupied and Manuel Schabus

References Bergamasco, B., Bergamini, L., Doriguzzi, T., & Fabiani, D. (1968). EEG sleep patterns as a prognostic criterion in post-traumatic coma. Electroencephalography & Clinical Neurophysiology, 24(4), 374-377. Cologan, V., Schabus, M., Ledoux, D., Moonen, G., Maquet, P., & Laureys, S. (2010). Sleep in disorders of consciousness. Sleep Medi¬ cine Reviews, 14(2), 97-105. Evans, B.M., & Bartlett, J.R. (1995). Predic¬ tion of outcome in severe head injury based on recognition of sleep related activity in the polygraphic electroencephalogram. Journal

then emerged onto land from the primordium of ancient oceans sleep? Did dino¬ saurs sleep? And if these organisms did sleep, what function, if any, did sleep serve in the survival of species? One approach to answering these questions may be to exam¬ ine living organisms with ancient origins that have changed little from their ancient fossil ancestors. Mammalian species, most often the subject of modern sleep studies, emerged relatively recently in the fossil record, between 100 and 74 million years ago (Bininda-Emonds et al., 2007). On the other hand, a living, diverse group of

of Neurology, Neurosurgery, and Psychia¬

organisms with ancient origins is insects.

try, 59(1), 17-25.

Insects first appeared in the fossil record

Freedman, N. S., Gazendam, J., Levan, L., Pack, A. I., & Schwab, R.J. (2001). Ab¬ normal sleep/wake cycles and the effect of environmental noise on sleep disruption in the intensive care unit. American Journal

approximately 400 million years ago, and modern insect orders, many of which have changed little from their early ancestors, have a fossil record extending to approxi¬

of Respiratory and Critical Care Medicine,

mately 250 million years ago (Grimaldi &

163(2), 451-457.

Engel, 2005). Thus, by studying insects,




Sleep in Insects

clues to the origins and function of sleep

the day with locomotor activity and de¬

in living organisms could potentially be

creased at night with behavioral quies¬


cence. The homeostatic response to sleep

The first issue in studying insect sleep

deprivation in the honey bee was further

is whether insects meet the behavioral cri¬

documented as were age-related changes in

teria for sleep. The evidence strongly sug¬

rest-activity cycles. Differences in honey

gests that insects do, in fact, meet these

bee castes have been associated with differ¬

criteria. The behavioral criteria include a

ences in the circadian rhythmicity of sleep.

species-specific posture, behavioral quies¬

Finally, neuroanatomical plasticity in sen¬

cence, elevated arousal thresholds, revers¬

sory processing centers in the insect brain,

ibility of quiescence with stimulation, and

specifically the mushroom bodies, suggests

the homeostatic drive or rebound in sleep

that aging and social experience may affect

following deprivation. The first naturalistic

the expression of sleep in insects.

observational studies of wasps, bees, flies,

The most detailed information on the

dragonflies, butterflies, and moths at the

physiology and neurochemistry of sleep

beginning of the 20th century are consis¬

has emerged from studies in Drosophila,

tent with these well-established behavioral

the fruit fly. Drosophila has been proposed

criteria. Recent work in the cockroach has

as a model organism for the study of sleep.

demonstrated that the metabolic response

This small organism presents several ad¬

to sleep deprivation as well as the effects of

vantages in the study of basic sleep mech¬

sleep deprivation on longevity are similar

anisms, including (1) the similarities in

to those in mammals, further strengthening

genetic sequence to human disease genes;

the argument that quiescence in insects is,

(2) the identification of well-studied mam¬

in fact, sleep, and that this quiescence is

malian neurotransmitter systems, with the

functionally similar to sleep in mammals

exception of orexin/hypocretin; and (3) the

(Stephenson, Chu, & Lee, 2007).

small size, rapid reproductive cycle, and

With the exception of an expanding lit¬

short life span that allow for rapid assess¬

erature in Drosophila, the number of sys¬

ment of genetic and molecular manipula¬

tematic studies on insect sleep is relatively

tions. However, the question arises as to

small. (For a full review of this literature

whether Drosophila meets the criteria for

see Hartse, 2010.) Although the electro¬

sleep and whether it can be used as a model

physiology of sleep is most often studied in

for the broader study of sleep mechanisms.

mammals, the electrophysiology of insect

The literature strongly supports simi¬

sleep is virtually unknown with a few ex¬

larities between behavioral sleep in Dro¬

ceptions. In one of a series of detailed stud¬

sophila and mammalian sleep. Drosophila

ies on the honey bee, performed by Kaiser

exhibits a species-specific posture during

and associates, the electrophysiology of

quiescence, elevated arousal thresholds,

optomotor interneurons displayed a circa¬

and a homeostatic response to quiescence

dian sensitivity to horizontal movement of

deprivation. Furthermore, there are age-

a light stimulus (Kaiser & Steiner-Kaiser,

related declines in behavioral quiescence

1983). This sensitivity increased during

similar to those observed in mammals, and

Sleep in Insects


A busy day in the flowers before the sun goes down. (Kristyna M. Hartse)

in both mammals and Drosophila there is a

One important area in which it is unlikely

similar alerting response to drugs, includ¬

that there will ever be convincing similari¬

ing caffeine, modafinil, and methamphet-

ties between mammals and Drosophila is

amine. Likewise, there is a similar response

in the electrophysiology of sleep, due to

of increasing quiescence following antihis¬

the neuroanatomical dissimilarities in brain

tamine administration in both mammals

structure. There is, however, evidence to

and Drosophila. Besides these findings,

suggest an electrophysiological correlate

there are additional important similarities

of quiescence recorded from Drosophila

between mammalian sleep and Drosophila

mushroom bodies. During waking there are


bursting local field potentials (LFPs) in the




Sleep in Patients with Alzheimer’s Disease

mushroom bodies, which diminish with be¬ havioral sleep, although it is clear that the absence of a waveform during Drosophila behavioral sleep is not equivalent to the presence of, for example, slow waves and sleep spindles, during mammalian sleep.

Grenyer, R., et al. (2007). The delayed rise of present-day mammals. Nature, 446, 507-512. Grimaldi, D., & Engel, M. S. (2005). Evolution of the insects. Cambridge: Cambridge Uni¬ versity Press.

The genetic identification of short-

Hartse, K. M. (2010). Sleep in insects. In P. Mc¬ Namara, R. A. Barton, & C.L. Nunn (Eds.),

sleeping fly strains as well as the genetic

Evolution of sleep: Phylogenetic and func¬


tional perspectives (pp. 34-55). Cambridge:




male and female flies suggest possible applications to human sleep disorders. Furthermore, the effect of aging on the de¬ terioration in human sleep quality has been well studied, and studies in Drosophila suggest that oxidative stress produces de¬ terioration of sleep in aged tlies. Another area of similarity between mammalian and Drosophila sleep is in the similari¬ ties of response to signaling pathways and neurotransmitters,


Cambridge University Press. Kaiser, W., & Steiner-Kaiser, J. (1983). Neu¬ ronal correlates of sleep, wakefulness, and arousal in a diurnal insect. Nature, 301, 707-709. Stephenson, R., Chu, K. M., & Lee, J. (2007). Prolonged deprivation of sleep¬ like rest raises metabolic rate in the Pa¬ cific beetle cockroach, Diploptera punctata (Eschscholtz). Journal of Experimental Bi¬ ology, 210, 2540-2547.


dopamine, and GABA. There may be neu¬ rotransmitters unique to Drosophila and other invertebrates, such as octopamine,

Sleep in Patients with Alzheimer’s Disease

and neurotransmitters unique to mammals, such as orexin/hypocretin, which serve

Alzheimer’s disease (AD) is the most

unique functions in each species.

common form of dementia in the United

The study of insects, and specifically

States. Current estimates indicate that 5.1

Drosophila, provides a potentially unique

million Americans are living with AD.

portal into the genetic and neurochemi¬

The prevalence increases with age, with

cal bases of the mysteries of sleep. Ide¬

60 percent of those more than the age of

ally, insect studies will ultimately have

85 years affected. It is estimated that by

broader applicability to the understanding

the year 2050, 11 to 16 million individu¬

of human sleep disorders and consequently

als will have AD (Plassman et al., 2007).

to the development of more effective, tar¬

Cross-sectional studies suggest that ap¬

geted treatments for these disorders.

proximately 25 to 35 percent of individuals

Kristyna M. Hartse See also: entries related to Evolution of Sleep

with AD have problems sleeping (Dauvilliers, 2007). Sleep disturbances in AD are complex. These patients are susceptible to


all of the sleep problems related to aging,

Bininda-Emonds, O.R.P., Cardillo, M., Jones, K. E., MacPhee, R.D.E., Beck, R.M.D.,

as well as to a progressive deterioration and decrease in the number of neurons in

Sleep in Patients with Alzheimer’s Disease


the suprachiasmatic nucleus (SCN), which

of N2 sleep from N1 sleep. Sleep spindles

is critical in the homeostatic maintenance

and K-complexes are poorly formed. They

of the circadian rhythm (Wu & Swaab,

are also of lower amplitude, shorter dura¬

2007). Common symptoms include night¬

tion, and less numerous (Montplaisir, Petit,

time sleep fragmentation, increased sleep

Lorrain, Gauthier, & Nielsen, 1995; Prinz

latency, decreased slow-wave sleep, and

et al., 1982) than is the case in normal aging.

increased daytime napping.

The proportion of NREM sleep increases

The relationship between sleep pathol¬

with further disappearance of the true delta

ogy and the pathogenesis of AD may be

wave pattern of slow-wave sleep (Mont¬

even more complex. Amyloid-(3 (A|3) ac¬

plaisir et al., 1995; Prinz et al., 1982). The

cumulation in the brain extracellular space

percentage of time spent in REM sleep,

is considered to be a hallmark of AD, al¬

which remains stable with normal aging, is

though the precise role of A (3 in patho¬

reduced in patients with AD. A decrease in

gens is still not completely understood.

the mean REM-sleep-episode duration and

In a transgenic mouse model, it has been

REM-sleep percentage has been attributed

shown that chronic sleep restriction sig¬

to degeneration of the nucleus basalis of

nificantly increased A(3 plaque formation

Meynert. The nucleus normally exerts an

while a dual orexin receptor antagonist de¬

inhibitory influence on the nucleus reticu¬

creased A(3 plaque formation. Thus, the

laris of the thalamus, the rhythm generator

sleep-wake cycle and orexin may play

responsible for NREM sleep (Buzsaki et

a role in the pathogenesis of AD (Kang

al., 1998). REM sleep also depends on the

et al., 2009). This relationship between

abundance and integrity of the choliner¬

sleep and the pathophysiology of AD may

gic system. The cholinergic disturbance in

also be reflected in the observation that

AD is accompanied by worsening of REM

sleep disturbances should be considered as

sleep. In addition, many subcortical struc¬

one of the core noncognitive symptoms of

tures such as the basal forebrain, distal and

mild cognitive impairment, or MCI, a con¬

superior raphe nucleus, and the reticular

dition often thought to be a precursor to

formation of the pons and medulla seem

AD (Beaulieu-Bonneau & Hudon, 2009).

to be involved in the initiation of sleep and oscillation between REM and non-REM

Sleep Architecture

states. All of these structures may be af¬ fected by the degenerative changes that

Certain sleep changes in AD seem to rep¬

are part of AD. Their deterioration may ac¬

resent an exaggeration of changes that

count for the sleep architecture and rhythm

appear with normal aging. AD patients

changes in AD (Weldemichael & Gross-

spend an increased amount of time in the

berg, 2010). The impact on REM may also

N1 stage of sleep with increased number

be reflected in the observation that REM

and duration of awakenings, compared

sleep without atonia may be more common

to age-matched non-AD controls (Prinz

in AD, even though the behavioral corre¬

et al., 1982). With disease progression, it is

late of REM sleep behavior disorder is rel¬

also very difficult to separate EEG features

atively uncommon (Gagnon et al., 2006).




Sleep in Patients with Alzheimer’s Disease

Circadian Rhythms

frequencies of REM-sleep EEG, suggest¬ ing a possible action on REM sleep-related

There is also a progressive deterioration

cholinergic neurons in patients with AD.

of circadian rhythms with aging. These in¬

Furthermore, REM sleep alpha power may

clude changes manifested by reductions in

predict the cognitive response to donepe¬

sleep quality and impairment in cognitive

zil (Moraes Wdos et ah, 2006). Although

performance (Yu et ah, 2009). The changes

some reviews suggest no particular impact

in the sleep-wake cycle have been attrib¬

of galantamine on REM sleep (Stahl, Mar¬

uted to alterations in the SCN and melato¬

kowitz, Papadopoulos, & Sadik, 2004),

nin secretion (Hu, Van Someren, Shea, &

there are case reports of galantamine caus¬

Scheer, 2009). Though not clear, genetic

ing unusual nightmares (Iraqi & Hughes,

risk factors such as in AD patients who

2009) and rivastigmine causing REM sleep

are negative for the ApoE4 allele have also

behavior disorder (Yeh, Yeh, & Schenck,

been implicated in the development of

2010) . The impact of donepezil on REM

sleep problems (Craig, Hart, & Passmore,

sleep is not always clear (Cooke et ah,


2006), but there are studies suggesting

Studies of circadian core body tempera¬

an increase in REM sleep with treatment

ture rhythms in patients with probable AD

by donepezil in healthy volunteers after

have shown a reduction in endogenous cir¬

a single dose (Kanbayashi et ah, 2002).

cadian amplitude and a delay in endogenous circadian phase of core body temperature (Ancoli-Israel et ah, 1997). AD patients, however, have shown only a slight de¬ crease in endogenous circadian amplitude when compared to normal aging, so it is unclear whether this is simply an exaggera¬ tion of normal aging (Czeisler et ah, 1992).

Donepezil may also reduce decline in rec¬ ognition performance in individuals vul¬ nerable to the effects of sleep deprivation (Chuah et ah, 2009). Of additional note is that cholinergic activity follows a circa¬ dian pattern. As a consequence, improved function may be seen during the day, but at night, there is an increased risk of sleep disruption (Davis & Sadik, 2006). Sanford Auerbach

Impact of Commonly Used Medications in AD

See also: entries related to Sleep and the Brain

Acetylcholinesterase inhibitors (ACHEIs)


are a group of agents that have been FDA

Ancoli-Israel, S., Klauber, M. R., Jones, D. W., Kripke, D. F., Martin, J., Mason, W.,... Fell, R. (1997). Variations in circadian rhythms of activity, sleep, and light exposure related to dementia in nursing-home patients. Sleep, 20(1), 18-23.

approved for the treatment of AD. The commonly used ACHEIs include donepezil, rivastigmine, and galantamine. These are of particular interest because of con¬ cern that the central cholinergic effect will have an impact on sleep and, in particular, REM sleep. Donepezil treatment appears to enhance REM sleep and reduce slow

Beaulieu-Bonneau, S., & Hudon, C. (2009). Sleep disturbances in older adults with mild cognitive impairment. International Psy¬ chogeriatrics, 27(4), 654-666.

Sleep in Patients with Alzheimer’s Disease

Buzsaki, G., Bickford, R. G., Ponomareff, G., Thai, L.J., Mandel, R., & Gage, F.H. (1998). Nucleus basalis and thalamic con¬ trol of neocortical activity in the freely mov¬ ing rat. Journal of Neuroscience, 8(11), 4007-4026. Chuah, L.Y., Chong, D.L., Chen, A.K., Rekshan, W.R., III, Tan, J. C., Zheng, H., & Chee, M.W. (2009). Donepezil improves episodic memory in young individuals vul¬ nerable to the effects of sleep deprivation. Sleep, 82(8), 999-1010. Cooke, J. R., Loredo, J. S., Liu, L., Marler, M., Corey-Bloom, J., Fiorentino, L., . . . Ancoli-Israel, S. (2006). Acetylcholinesterase inhibitors and sleep architecture in patients with Alzheimer’s disease. Drugs and Aging, 25(6), 503-511.


Hu, K., Van Someren, E.J., Shea, S.A., & Scheer, F. A. (2009). Reduction of scale in¬ variance of activity fluctuations with aging and Alzheimer’s disease: Involvement of the circadian pacemaker. Proceedings of the National Academy of Sciences of the United States of America, 706(8), 2490-2494.

Iraqi, A., & Hughes, T. L. (2009). An unusual case of nightmares with Galantamine. Jour¬ nal of the American Geriatrics Society,

57(3), 565. Kanbayashi, T., Sugiyama, T., Aizawa, R., Saito, Y., Ogawa, Y., Kitajima, T., . . . Shi¬ mizu, T. (2002). Effects of donepezil (Aricept) on the rapid eye movement sleep of normal subjects. Psychiatry and Clinical Neurosciences, 56(3), 307-308.

Craig, D., Hart, D. J., & Passmore, A. P. (2006). Genetically increased risk of sleep disrup¬ tion in Alzheimer’s disease. Sleep, 29(8), 1003-1007.

Kang, J.E., Lim, M.M., Bateman, R.J., Lee, J. J., Smyth, L. P., Cirrito, J. R.,... Holtzman, D.M. (2009). Amyloid-beta dynamics are regulated by orexin and the sleep-wake cycle. Science, 326(5955), 1005-1007.

Czeisler, C.A., Dumont, M., Duffy, J.F., Steinberg, J.D., Richardson, G. S., Brown, E.N., . . . Ronda, J.M. (1992). Association of sleep-wake habits in older people with changes in output of circadian pacemaker. Lancet, 540(8825), 933-936.

Montplaisir, J., Petit, D., Lorrain, D., Gauthier, S., & Nielsen, T. (1995). Sleep in Alzheim¬ er’s disease: Further considerations on the role of brainstem and forebrain choliner¬ gic populations in sleep-wake mechanisms. Sleep, 18(3), 145-148.

Dauvilliers, Y. (2007). Insomnia in patients with neurodegenerative conditions. Sleep Medicine, 4(Suppl. 4), S27-S34. (Note: This article reviews neurodegenerative disorders associated with dementing illnesses and characteristic sleep disturbances related to these conditions.)

MoraesWdos,S.,Poyares,D.R.,Guilleminault, C., Ramos, L. R., Bertolucci, P. H., & Tufik, S. (2006). The effect of donepezil on sleep and REM sleep EEG in patients with Al¬ zheimer disease: A double-blind placebocontrolled study. Sleep, 29(2), 199-205.

Davis, B., & Sadik, K. (2006). Circadian cho¬ linergic rhythms: Implications for cho¬ linesterase inhibitor therapy. Dementia and Geriatric Cognitive Disorders, 21(2),

120-129. Gagnon, J.F., Petit, D., Fantini, M.L., Rompre, S., Gauthier, S., Panisset, M., . . . Montplaisir, J. (2006). REM sleep behavior disorder and REM sleep without atonia in probable Alzheimer disease. Sleep, 29(10), 1321-1325.

Plassman, B.L., Langa, K.M., Fisher, G.G., Herringa, S.G., Weir, D. R., Ofstedal, M. B.,... Wallace, R. B. (2007). Prevalence of dementia in the United States: The aging, demographics, and memory study. Neuro¬ epidemiology, 29(1-2), 125-132. Prinz, P.N., Peskind, E. R., Vitaliano, P.P., Raskind, M. A., Eisdorfer, C., Zemcuznikov, N. , & Gerber, C.J. (1982). Changes in the sleep and waking EEGs of nondemented and demented elderly subjects. Journal of the American Geriatrics Society, 50(2), 86-93.




Sleep in Patients with Parkinson’s Disease

Stahl, S.M., Markowitz, J.S., Papadopoulos, G., & Sadik, K. (2004). Examination of nighttime sleep-related problems dur¬ ing double-blind, placebo-controlled trials of galantamine in patients with Alzheim¬ er’s disease. Current Medical Research and Opinion, 20(4), 517-524.

patients, virtually all of them manifest in¬

Weldemichael, D.A., & Grossberg, G.T. (2010). Circadian rhythm disturbances in patients with Alzheimer’s disease: A re¬ view. International Journal of Alzheimer’s Disease, Article ID 716453, 9 pages.

pressed and not demented show decreases

Wu, Y.H., & Swaab, D.F. (2007). Disturbance and strategies for reactivation of the circa¬ dian rhythm system in aging and Alzheim¬ er’s disease. Sleep Medicine, 8(6), 623-636. Yeh, S. B., Yeh, P. Y„ & Schenck, C. H. (2010). Rivastigmine-induced REM sleep behavior disorder (RBD) in a 88-year-old man with Alzheimer’s disease. Journal of Clinical Sleep Medicine, 6(2), 192-195. Yu, J.M., Tseng, I.J., Yuan, R. Y., Sheu, J.J., Liu, H.C., & Hu, C.J. (2009). Low sleep efficiency in patients with cognitive impair¬ ment. Acta Neurologica Taiwanica, 18(2), 91-97.

somnia, excessive daytime sleepiness, in¬ tense dreams, and abnormal movements at night. Laboratory (polysomnographic and electroencephalographic or EEG) studies of sleep in PD patients who are not de¬ in sleep efficiency, as well as increases in sleep fragmentation with multiple nightwakings. By contrast, in normal aging, sleep problems typically involve a reduc¬ tion in slow-wave sleep duration and few if any abnormalities of REM sleep. Why might PD be associated with sleep problems? The neuropathology of PD is consis¬ tent with dysfunction of sleep mechanisms in PD patients. The classical sleep cen¬ ters that control sleep onset and offset as well as sleep intensity are located in the brain stem and hypothalamus—both sites that are severely affected by PD. In addi¬ tion, the primary pathology of PD involves loss of dopaminergic cells in the substan¬ tia nigra (SN) and in the ventral tegmental

Sleep in Patients with Parkinson’s Disease

area. These two subcortical dopaminergic sites give rise to two projection systems important for arousal, motor, affective,

Although Parkinson’s disease (PD) is pri¬

and cognitive functioning. The nigrostria-

marily thought of as a motor disorder (the

tal system, primarily implicated in motor

shaking palsy), sleep problems of varying

functions, originates in the pars compacta

degrees and types occur in up to 74 to 98

of the SN and terminates in the striatum.

percent of patients with PD. Sleep prob¬

The meso-limbic-cortical system origi¬

lems may even predict the onset of PD

nates in the ventral tegmental area (VTA)

by some 5 to 10 years. Sleep problems,

and terminates in the ventral striatum, lim¬

finally, may contribute to or exacerbate

bic sites, amygdala, frontal lobes, and some

some of the mood and cognitive disorders

other basal forebrain areas. Dopamine lev¬

seen in PD patients. Thus, PD might be bet¬

els in the ventral striatum, frontal lobes,

ter understood as both a motor and a sleep

and hippocampus of PD patients are ap¬

disorder. Although the kinds and severity

proximately 40 percent of normal. The

of sleep problems vary tremendously in PD

termination sites of both the nigrostriatal

Sleep in Patients with Parkinson’s Disease


and the meso-cortical dopamine systems

Insomnia refers to the inability to fall

are all important for sleep processes, par¬

asleep or to stay asleep long enough to

ticularly REM sleep. Disrupting these sites

achieve restorative benefits of sleep. PD

via reduced dopaminergic stimulation may

patients with insomnia lie awake at night,

also affect sleep.

and when they finally fall asleep, they

In addition to the dopaminergic dysfunc¬

awaken a couple of hours later feeling un¬

tion associated with PD there is also Lewy

refreshed. Polysomnographic and EEG

body (LB) degeneration, and Alzheimer-

studies of sleep in PD patients who are not

type changes that have been notedin brain

depressed show decreases in deep sleep,

stem nuclei (including the noradrener¬

too much light sleep (Stage II), as well as

gic locus coeruleus and the serotonergic

increases in sleep fragmentation and mul¬

dorsal raphe nucleus—two sites impli¬

tiple night-wakings.

cated in sleep and arousal mechanisms), limbic structures, cholinergic forebrain structures, and in the cerebral cortex. The cholinergic pathology in the basal fore¬

Excessive Daytime Sleepiness (EDS) in PD

brain structures and the LB-type degenera¬

EDS is found in as many as 50 percent of

tion in limbic and in the cerebral cortex are

PD patients and serious fatigue in about

also likely contributors to sleep disorders,

60 percent of patients. Periodic limb

dementia of PD, and to affective dysfunc¬

movements, obstructive sleep apnea, and

tion of PD.

depression may all contribute to sleep

In summary, there is no shortage of rea¬

maintenance problems and EDS. In addi¬

sons to expect sleep dysfunction in PD pa¬

tion, parkinsonian medications themselves

tients. But we can cite further contributing

may contribute to the excessive sleepiness.

factors as well: The classic motor problems

There have been several reports arguing

of PD such as rigidity make it difficult to

that use of dopamine agonists, pramipex-

get comfortable or to turn over in bed. The

ole, and ropinirole is associated with sud¬

medications used to treat motor symptoms

den and irresistible sleep attacks during the

of PD may have all kinds of contradictor ef¬

day in some PD patients. But other stud¬

fects on sleep: some may make the patient

ies have failed to find any association be¬

drowsy while others may over arouse the

tween agonists and EDS. Mood problems

patient. Linally the anxiety and depression

also seem to be related to ESD in PD pa¬

associated with PD may influence ability

tients. In some recent studies EDS was

to fall asleep or to achieve restful sleep.

related primarily to anxiety levels rather

I now turn to a brief survey of major sleep disorders of PD.

than to depression, stress, stage of dis¬ ease, neuropsychological dysfunction, or to medication-related factors. In sum, the

Insomnia in PD

causes of EDS in PD patients remain un¬ clear, but dopaminergic medications and

There are no good estimates of the num¬

anxiety levels are likely to be important

ber of PD patients who report insomnia.





Sleep in Patients with Parkinson’s Disease

Sleep Disorder Breathing and Sleep Apnea in PD

REM Sleep Behavior Disorder (RBD)

Apnea refers to episodes of cessation of

This is the disorder that may herald the

breathing during sleep. Central sleep apnea

onset of PD by as much as 10 to 15 years.

refers to a problem in the brain stem centers

RBD involves the loss of the normal motor

that control respiration. Obstructive sleep

inhibition associated with REM sleep so

apnea refers to blockage in the breathing

that patients literally begin to act out their

passages (nose, throat, etc.). When the pa¬

dreams. While estimates vary dramatically,

tient with sleep apnea attempts to enter

it appears that approximately 50 percent of

deep sleep, he stops breathing and then

PD patients have partial or complete loss of

this lack of oxygen prompts him to wake

muscle atonia during rapid eye movement

up briefly to get some air. The awakening

(REM) sleep. It is particularly interesting

may not be conscious as it is often very

that most of the dreams that RBD patients

brief, but it may happen dozens of times

act out and report upon awakening are

each night so that the person’s sleep is

filled with aggression. Common themes

fragmented and filled only with light rather

are that the patient or his wife or bed part¬

than deep restorative sleep. During the

ner is being attacked by intruders, etc.,

daytime, the individual feels overwhelm¬

and the patient physically, and sometimes

ing fatigue and a drive for sleep. Prelimi¬

violently, defends against the attack. One

nary studies of sleep disordered breathing

recent study of dream content in RBD pa¬

in PD populations suggests that more than

tients demonstrated that compared to con¬

half of PD patients suffer some degree of

trols, patients with RBD reported a very

apnea with obstructive sleep apnea being

high degree of aggression in their dreams.

the most commonly documented form.

Sixty-six percent of RBD dreams and only 15 percent of control dreams had at least

Periodic Limb Movement Disorder and Restless Legs Syndrome (RLS)

one episode of aggression. The percentage

Periodic limb movements during the night

that of controls (86% vs. 44%).

of aggressive episodes to friendly interac¬ tions in dreams of RBD patients was twice

are quite common in the elderly, including

The dream-enactment episodes are so

PD patients. RLS, which is frequently as¬

real for the patients that they often injure

sociated with periodic limb movements, is

themselves during an episode. Indeed, in¬

frequently seen in the middle-aged popu¬

juries are reported by more than 75 per¬

lation, in the elderly, and in PD patients.

cent of patients. Video-polysomnographic

In both disorders, there is a sensation in

monitoring reveals that hallucinatory epi¬

the legs that causes the patient to move his

sodes typically occur during REM sleep.

or her extremities and may contribute to

Interestingly, varying degrees of RBD

insomnia. The PD patient with RLS often

may be present for years before the motoric

feels an irresistible urge to move the legs

manifestations of PD develop. One study

around during the night to get comfortable.

of PD patients with RBD investigators

Sleep in Patients with Parkinson’s Disease


found that the nighttime dream-related en¬

matter how long one stays in bed or sleeps.

actment behaviors developed an average

Some of these same sleep-related phenom¬

of three years before the motoric disorder

ena occur in PD patients with depression,

(parkinsonism) in about half of those who

but there are few controlled studies that

had both conditions.

have identified special aspects of sleep dys¬ function in PD patients with depression.

Sleep and Hallucinations in PD Vivid dreams in PD patients often predict daytime hallucinations. Many PD patients without overt RBD report episodes of hal¬ lucinations. Hallucinations are thought to be experienced by as many as 33 percent of PD patients during the course of their illness. They are generally thought to be a complication of dopaminergic pharma¬ cotherapy and when present limit drug therapy for motor disability. They are, fur¬ thermore, a significant risk factor for nurs¬ ing home placement. Hallucinations in PD patients tend to occur in the visual rather than auditory modality and are frequently associated with vivid dreams. Interest¬ ingly, sleep disturbance is more common in hallucinators than in nonhallucinators, and therefore sleep problems rather than the medications per se may be potent con¬ tributors to hallucinosis in PD patients.

Sleep and Cognitive Disorders of PD It should be noted briefly that PD is also associated




especially in mid and later stages of the dis¬ ease. These deficits involve problems with memory, attention, and concentration. Be¬ cause sleep is known to be involved in consolidation of memory, it follows that disruption of sleep, as occurs in PD, may also contribute to cognitive disorders of PD—but this proposition has not been thoroughly tested as yet. In summary, disturbances in sleep, with its related consequences for mood and mind, obviously cause problems and re¬ duce the quality of life for both the patient and for the caregiver. Furthermore, an un¬ derstanding of the causal relationships be¬ tween sleep and PD symptoms may lead to better treatment and to better quality of

Sleep and Depression in PD Chronic depression is seen in approxi¬ mately 40 percent of PD patients but major depression in PD is unlike reactive forms of depression in that it is characterized by prominent anxiety and less proclivity to¬ ward self-punitive ideation. In other forms of major depression sleep dysfunction is a prominent and core symptom of the disease. Typically the problem is reduced REM latency and nonrestorative sleep no

life for PD patients and their caregivers. In particular, if sleep dysfunction contrib¬ utes to the development of cognitive (e.g., dementia) and affective (e.g., depression) dysfunction in PD patients, then early and aggressive therapies to treat sleep disor¬ ders could delay the development of cog¬ nitive, mood, and dementing illnesses in this population. Patrick McNamara See also: entries related to Sleep and the Brain




Sleep in Patients with Wilson’s Disease


WD patients and their physicians paying

Stacy, M. (2002). Sleep disorders in Par¬

no attention to them. The first to notice in¬

kinson’s disease: Epidemiology and man¬

creased sleep problems in a significant co¬

agement. Drugs Aging, 79(10), 733-739.

hort were Portala, Westermark, Ekselius, and Broman (2002). The authors examined a group of 24 WD patients in a question¬

Sleep in Patients with Wilson’s Disease

naire study, and found statistic differences from their reference group in quantitative sleep variables (difficulties falling asleep,

Wilson’s disease (WD) is an autosomal

greater number of awakenings per night,

recessive inherited disorder of copper me¬

sleepiness during the day), in daytime

tabolism resulting in pathological accumu¬

functions (fatigue, taking naps), and in

lation of copper in many organs and tissues.

REM-sleep disturbances (sleep paralysis,

The disease is caused by a deficiency of a

cataplexy). A total of 42 percent of treated

copper-transporting P-type ATPase (Bull,

WD patients had sleep problems. The con¬

Thomas, Rommens, Forbes, & Cox, 1993),

clusion was that the sleep complaints can

encoded by mutation of the ATP7B gene on

be explained by disturbances in monoami-

chromosome 13 (band ql4.3). More than

nergic neurons (REM-off neurons) at the

500 different forms of mutation have been

brain stem level resulting in altered REM-

identified up to now. Copper accumulation

sleep function. Enhancement by altered

results in a variety of symptoms ranging

circadian functions, localized in suprachi-

from neurological and/or psychiatric dis¬

asmatic nuclei, can be considered as well.

turbances to acute or chronic liver disease.

The high frequency of sleep comorbidity

Two main clinical forms—hepatic and

compared with the control group was cor¬

neurological—are usually distinguished.

roborated in another study (Nevsfmalova

The latter—present in about 40 percent of

et al., in press). Its authors examined 55

those affected—include dysarthria, dys¬

patients with WD in a questionnaire study,

praxia, ataxia, and extrapyramidal signs,

and the results correlated with age- and

mostly of the dystonic kind (Kitzberger,

sex-matched control subjects. The ques¬

Madl, & Ferenci, 2005). Neuropsychi¬

tions were centered on sleep habits and

atric features include a cognitive decline

sleep disorder comorbidities. The patients,

together with personality changes, mood

as well as the control group, were then

disorders; even schizophreniform disor¬

asked to fill in the Epworth sleepiness scale

ders can accompany the clinical symp¬

measuring chronic sleepiness and a screen¬

toms. Treatment with penicillamine, zinc,

ing questionnaire for REM sleep behavior

or trientine is lifelong (even in asymptom¬

disorder (RBD). Twenty-four patients un¬

atic cases) for a good response. Most WD

derwent a sleep study—nocturnal video¬

patients can resume a good quality of life.

polysomnography, followed by daytime

Sleep complaints, relatively frequently

multiple sleep latency testing (MSLT).

accompanying the clinical features of WD,

According to the results, the values

however, mostly go unrecognized with

of daytime napping, excessive daytime

Sleep, Inflammation, and Cardiovascular Disease


sleepiness, cataplexy-like episodes, and

of the sleep/wake symptoms also includes

poor nocturnal sleep were significantly

altered REM-sleep-dissociated symptoms.

higher. Elevated subjective sleepiness was

Sana Nevsimalova

found in almost one third of our WD ques¬ tionnaire respondents, and MSLT revealed

See also: entries related to Hormones in Sleep; entries related to Sleep and the Brain

borderline or shortened mean sleep latency again in one third of the cohort. Although


the changes were found more frequently

Barthel, H., Hermann, W., Kluge, R., Hesse, S., Collingridge, D. R., Wagner, A., & Sabri, O. (2003). Concordant pre- and postsynaptic deficits of dopaminergic neurotransmission in neurologic Wilson disease. American Journal of Neuroradiology, 24, 234-238.

in patients with the neurological than in the hepatic form, the difference was non¬ significant. There were also surprisingly many




toms occurring in narcolepsy, particularly cataplexy-like episodes and vivid dreams, but neither nocturnal polysomnography nor MSLT confirmed any sleep-onset REM periods in the patients’ records. Al¬ most half the WD patients responded posi¬ tively to five or more screening questions suggesting conceivable clinical symptoms of RBD, more frequently so patients treated with D-penicillamine. Horrible nightmares accompanied by screaming loud and even nocturnal injuries were among their com¬ plaints. However, signs of REM sleep without atonia, which is typical of RBD, appeared in several patients, but none

Bull, A. I., Thomas, G. R., Rommens, J. M., Forbes, J. R„ & Cox, D. W. (1993). The Wil¬ son disease gene is a putative copper trans¬ porting P-type ATPase similar to Menkes disease gene. Nature Genetics, 5, 327-337. Kitzberger, R., Madl, C., & Ferenci, P. (2005). Wilson disease. Metabolic Brain Disease, 20, 295-302. Nevsimalova, S., Buskova, J., Bruha, R., Kemlink, D., Sonka, K., Vitek, L., & Marecek, Z. (in press). Sleep disorders in Wilson’s dis¬ ease. European Journal Neurology. Portala, K., Westermark, K., Ekselius, L., & Broman, J.E. (2002). Sleep in patients with treated Wilson’s disease: A questionnaire study. Nordic Journal of Psychiatry, 56, 291-297.

reached the straightforward criteria of 20 percent of the REM record that is neces¬ sary for RBD diagnosis. WD is supposed to be associated with a

Sleep, Inflammation, and Cardiovascular Disease

dopaminergic deficit (Barthel et al., 2003), which can explain at least some of the clin¬

Although scientists noted a relationship

ical symptoms. Therefore, impairment of

between inflammation and cardiovascu¬

basal ganglia at the nigrostriatal dopami¬

lar disease (CVD) as early as the 1920s, it

nergic level, and dysfunction of monoami-

was not until decades later that research¬

nergic neurons at the brain stem level help

ers began to examine more direct linkages

to account for the clinical variety of sleep


disturbances. In conclusion, WD patients often suffer

and CVD. Within the past 10 years there has been burgeoning interest in under¬

from sleep disturbances, and the spectrum

standing the mechanistic processes of







Sleep, Inflammation, and Cardiovascular Disease

how inflammation mediates the relation¬

(Mills & Dimsdale, 2004). Circulating

ship between disturbed sleep and CVD.

levels of IL-6 and TNF-a are elevated in

Cytokines regulate and mediate immune

individuals with obstructive sleep apnea

and other inflammatory-related responses.

(OSA) and are correlated with carotid

The functions of proinflammatory cyto¬

intima-media thickness, suggesting that

kines are diverse, including developing and

apnea-related systemic inflammation is

proliferating immune cell subsets, activat¬

associated with progression of atheroscle¬

ing adhesion molecules and blood coagula¬

rosis and increased risk of cardiovascular

tion pathways, supporting atherosclerotic

morbidity. The circulating soluble receptor

processes, and altering neurochemical and

1 of TNF is also elevated in sleep apnea

neuroendocrine processes. While acutely

and associated with the number of arous-

heightened inflammation states are a natu¬

als during the night, as well as associated

ral and needed part of the body’s immune re¬

with CVD incidence. One of the reasons

sponse to infection and injury, such states can

that nighttime sleep disturbance may in¬

adversely affect sleep quality and duration.

crease CVD risk is that although inflam¬

For example, interluekin-6 (IL-6) and tumor

mation is increased throughout the night

necrosis factor-alpha (TNF-a) are acutely el¬

in response to apneic events, it can remain

evated in response to bacterial infection and

elevated throughout the next day (Mills,

are associated with sickness behaviors, in¬

Natarajan, von Kanel, Ancoli-Israel, &

cluding fatigue and increased sleep duration.

Dimsdale, 2009).When sleep apnea is suc¬

Low-grade, chronic inflammation also

cessfully treated with continuous positive

brings adverse consequences to sleep that are

airway pressure, the inflammation associ¬

unremitting and ultimately can further exac¬

ated with apneic events is reduced.

erbate disease. For example, heart failure is

In addition to cytokines and their recep¬

characterized by significant inflammation

tors, endothelin-1 (ET-1) has been associ¬

across an extensive spectrum of pathways,

ated with disturbed sleep and CVD. ET-1

including immune cells, endothelial cells,

is a potent vasoconstrictor and mediator of

cardiac cells, and the liver. Heart failure is

inflammation that is elicited from endothe¬

also characterized by disturbed sleep, in¬

lial cells. The increase in blood pressure

cluding sleep apnea. Currently investiga¬

that acutely accompanies apneic events

tors are examining the degree to which the

can also increase endothelial shear stress,

chronic inflammation in heart failure is as¬

which results in endothelial production of

sociated with ongoing sleep disturbances,

ET-1. In OSA patients, ET-1 is strongly

and the potential for feedback loops of in¬

related to degree of hypertension (Gjorup

flammatory processes that further exac¬

et ah, 2007). The elevation of ET-1 in sleep

erbate symptoms and functional capacity

apnea appears to be' related to hypoxia, a

(Khayat, Patt, & Hayes, 2009).

state of inadequate oxygen saturation that

Sleep apnea is a good example of how

results from repeated breath suspensions.

disturbed sleep can enhance inflamma¬

Elevated ET-1 levels have been associated

tory states and subsequently contribute to

with greater sleep latency, greater rapid

the development or exacerbation of CVD

eye movement (REM) latency, and more

Sleep, Inflammation, and Cardiovascular Disease


slow-wave sleep in sleep apneics. Elevated

In summary, inflammation may medi¬

levels of ET-1 may be a consequence rather

ate the relationship between inadequate

than a determinant of sleep quality.

sleep and CVD risk. Studies of diseased

Although disease states provide settings

populations generally demonstrate that el¬

where the association between inflamma¬

evated levels of inflammation are associ¬

tion and sleep can be more easily observed,

ated with more disturbed sleep, and worse

such relationships can also be found in

cardiac prognosis. Although the data are

healthy individuals. Within normal phys¬

less straightforward for healthy individu¬

iological ranges, elevated circulating lev¬

als, there is also evidence to suggest that

els of IL-6 have been associated with

over time insufficient sleep may contribute

decreased slow-wave sleep and increased

to low-grade inflammation and, ultimately,

REM sleep. Elevated levels of IL-6 appear

increase risk of cardiac events.

to be associated with poor sleep quality; however, there is still no formal consensus on the relationship of IL-6 or any other in¬

Jessica Ann Jimenez and Paul J. Mills See also: entries related to Sleep and Health; entries related to Sleep Disorders

flammatory biomarker on sleep architec¬ ture in healthy individuals. Sleep disruption in healthy individu¬ als provides another setting for examining sleep and inflammation. Total or partial sleep deprivation can lead to significant short-term increases of daytime levels of IL-6, C-reactive protein, and TNF re¬ ceptors. These findings beg the question of whether chronic insufficient sleep in healthy individuals contributes to lowgrade inflammation and increased CVD risk. There is evidence to support such a position. Caregivers of Alzheimer’s dis¬ ease patients, who are at increased risk of CVD, show disrupted sleep as a result of their caregiving role, including greater amounts of time spent awake after initial sleep onset and lower overall sleep effi¬ ciency. These sleep disturbances are asso¬ ciated with elevated levels of IL-6 as well as the coagulation marker D-dimer (von Kanel, Loredo, Ancoli-Israel, & Dimsdale, 2006), both important mediators of the in¬ flammatory processes of CVD and both predict CVD outcomes.

References Gjorup, P. H., Sadauskiene, L., Wessels, J., Nyvad, O., Strange, B., & Pedersen, E.B. (2007). Abnormally increased endothelin-1 in plasma during the night in obstructive sleep apnea: Relation to blood pressure and severity of disease. American Jounral of Hypertension, 20(1), 44-52. Khayat, R., Patt, B., & Hayes, D. (2009). Ob¬ structive sleep apnea: The new cardiovascu¬ lar disease. Part I: Obstructive sleep apnea and the pathogenesis of vascular disease. Heart Failure Reviews, 74(3), 143-153. Mills, P.J., & Dimsdale, J.E. (2004). Sleep apnea: A model for studying cytokines, sleep, and sleep disruption. Brain, Behav¬ ior, and Immunity, 7S(4), 298-303. Mills, P., Natarajan, L., von Kanel, R., Ancoli-Israel, S., & Dimsdale, J. (2009). Diurnal variability of C-reactive protein in obstructive sleep apnea. Sleep and Breath¬ ing, 75(4), 415-420. von Kanel, R., Loredo, J., Ancoli-Israel, S., & Dimsdale, J. (2006). Association between sleep apnea severity and blood coagulabil¬ ity: Treatment effects of nasal continuous positive airway pressure. Sleep and Breath¬ ing, 70(3), 139-146.




Sleep Intensity and the Homeostatic Regulation of Sleep

Sleep Intensity and the Homeostatic Regulation of Sleep

animals is not building up some chemical that is depleted during waking, such as ad¬ enosine build-up in mammals. Moreover, SWA does not appear to increase after

The importance of the intensity dimen¬

sleep deprivation. Unlike mammals, sleep

sion of sleep was first uncovered in exper¬

spindles are absent during NREM in birds.

iments on effects of sleep deprivation. The

As in aquatic mammals, unilateral eye clo¬

most dramatic effect of sleep deprivation

sure and unihemispheric slow-wave sleep

in every mammalian species studied thus

(SWS) also occur in birds. In both mam¬

far has been the phenomenon of compen¬

malian and in avian species compensatory

satory rebound, or the increase over base¬

rebound involves a change in sleep-cycle

line of sleep times and intensity, where


intensity is measured by higher arousal

Borbely (1982) first formalized the in¬

thresholds, enhanced slow-wave activity

sight that mammalian sleep involved a

(SWA; particularly enhanced delta power

balance between sleep amount and sleep

when spectral EEG analysis is used), en¬

intensity and that sleep was therefore under

hanced REM frequencies per unit time,

homeostatic control. In his two-process

and deeper and longer sleep cycles. After

model of sleep regulation a sleep need pro¬

sleep deprivation, mammalian animals

cess (Process S) increases during waking

attempt to make up for lost sleep by en¬

(or sleep deprivation) and decreases dur¬

hancing the intensity and duration of sub¬

ing sleep. This part of the model indexes

sequent sleep. During the wakefulness or

restorative aspects of sleep and explicitly

deprivation period, neurochemicals are

predicts that sleep is required for some re¬

thought to accumulate in proportion to the

storative process of the brain or the body or

length of the wake period. One such possi¬

both. Process S is proposed to interact with

ble chemical is adenosine, which acts in a

input from the light-regulated circadian

sleep center (possibly the basal forebrain)

system (Process C) that is independent of

to inhibit arousal/increase sleepiness and

sleep and wakefulness rhythms. SWA is

then dissipates at a rate depending on sleep

taken as an indicator of the time course of

intensity until it returns to baseline dur¬

Process S, because SWA is known to cor¬

ing sleep. Birds too demonstrate a com¬

relate with arousal thresholds and to mark¬

pensatory rebound after sleep deprivation,

edly increase during the previous waking

but the rebound involves increased over¬

period and during the rebound period after

all sleep times and cycles rather than en¬

sleep deprivation in all mammals stud¬

hancements in SWA. Birds also appear to

ied. Once a threshold value of Process S

exhibit a special form of SWA and very

is reached (i.e., once the appropriate

little REM-like sleep. SWA in birds, how¬

amount and intensity of SWS is reached),

ever, does not appear to be homeostatically

Process C will be activated. Simulations

regulated. SWA in NREM sleep in pi¬

using the model’s assumptions show that

geons does not decline in the course of the

the homeostatic component of sleep falls

dark period, suggesting that SWA in these

in a sigmoidal manner during waking and

Sleep, Memory, and Dreams


rises in a saturating exponential manner

values for sleep cycle were very low; and

during sleep.

(3) no concerted attempts were made to

The two-process model does not ad¬

collect new data that index intensity (e.g.,

dress homeostatic aspects of REM. REM,

SWA). Nor had previous analyses con¬

however, evidences rebound after sleep

trolled for variables that are now known

deprivation, but here the intensity com¬

to alter intensity measures (torpor or

ponent is likely to be some process asso¬


ciated with frequency (density) of REMs per unit time. In any case both REM and NREM are under homeostatic control

Patrick McNamara See also: entries related to Sleep Assessment

and enhancements of sleep intensity over


baseline addresses the homeostatic need

Borbely, A. A. (1982). A two process model of sleep regulation. Human Neurobiology, 1, 195-204.

for sleep. In short, these findings led to the assumption that sleep intensity indexes functional need. Researchers have used a variety of mea¬ sures to evaluate sleep intensity, includ¬ ing SWA, duration of Stages III and IV or SWS, sleep-cycle length, spindling activ¬

Sleep, Memory, and Dreams Memory

ity, REM densities, and arousal thresholds.


These measures of intensity, however,

whereby recently acquired information is

need to be evaluated (via both reliability

converted to a more permanent, long-term

analyses and via exhaustive review of the

state, less vulnerable to disruption or loss.

literature on each measure) for their power

This dynamic process takes place over a

to index sleep intensity (Are they all mea¬

period of days, weeks, months, and even

suring the same thing?) and then ranked in

years. There are now understood to be at

order of reliability. It may be that SWA and

least two different memory systems, de¬

sleep-cycle lengths will rank first and sec¬

clarative and nondeclarative, that are rela¬

ond, as these are the measures that to date

tively independent of each other.

appear to best linked to restorative aspects of sleep.





Declarative material is easily accessi¬ ble to verbal description. The individual

Past comparative analyses of functional

is aware of the information that is to be

correlates of sleep quotas did not look

learned and aware that it can be accessed

at correlated evolution of sleep intensity

from memory store when desired. Declar¬

with other ecological and life-history

ative memory is further divided into se¬

variables. Analyses using proxies for in¬

mantic and episodic categories. Semantic

tensity (e.g., SWA, SWS, or sleep-cycle

memories comprise our factual knowledge

length) were necessarily limited because

of the world. Thus most of us know that

(1) no compilations of mean duration of

Paris is the capital of France. However,

SWS (Stage II and III NREM) were at¬

memory of when we acquired this infor¬

tempted; (2) the number of species with

mation is likely not available. Episodic




Sleep, Memory, and Dreams

memories include the information of in¬

The third type of NREM sleep consists of

terest as well as the contextual location of

large amplitude delta waves (1 to 4 Hz).

acquisition in time and place. Being able

This type of sleep, often called slow-wave

to recall what you ate for lunch as well as

sleep (SWS), is most prominent in the first

the fine details of who you were with and

third of the night and is minimal or absent

where you ate, is an example of an episodic

in the last third of the night. There is re¬


duced muscle tension in the large skel¬

Nondeclarative memories are not easily

etal muscle groups during NREM sleep,

accessible to verbal description. Usually,

but some tension remains and movement

learning does not occur at the conscious

is possible. There are no eye movements



during NREM sleep. During REM sleep,

memories exist can best be done by ob¬

the EEG frequency is 7 to 10 Hz. There are

serving behavior. If someone says that they

phasic conjugate rapid movements of the

have learned to skate, the best indication

eyes while the large skeletal muscles are

that they have done so is to give a skating

completely immobilized and movement is

demonstration. There are several subtypes

not possible.



of nondeclarative memory. They include

Throughout the night of sleep there is

procedural memory (skills and habits),

a 90-minute ultradian rhythm. Healthy

priming, and simple classical conditioning

young individuals begin the night with a

(which include emotional responses and

few minutes of Stage 1, which then gives

skeletal musculature responses) (Maquet,

way to Stage 2, which is then followed by

Smith, & Stickgold, 2003).

SWS. SWS is followed by a return to Stage 2 sleep and then a period of REM sleep oc¬

Sleep States

curs. The time for this cycle to complete is approximately 90 minutes. The individual

The states of sleep in humans are conven¬

then repeats the cycle by going from REM

tionally divided into two separate catego¬

sleep to Stage 2, SWS, and then REM again.

ries, rapid eye movement sleep (REM) and

As the night continues, the amount of SWS

nonrapid eye movement sleep (NREM).

diminishes and the amount of REM sleep

NREM sleep is further subdivided into

increases. By the last third of the night,

three categories. Stage 1 is a light stage of

only Stage 2 and REM sleep occur.

sleep, typically seen at sleep onset with an electrical brain wave (EEG) frequency of 7 to 9 Hz. It typically does not last more than a few minutes before giving way to

Sleep States and Memory Consolidation

Stage 2 sleep. This stage has a slower EEG

Three main approaches have been used

frequency of 5 to 7 Hz (often called theta


waves), as well as special intermittent fea¬

sleep states and memory processes. One

tures including the spindle (12 to 16 Hz)

method involved observing the changes

and the K-complex. About 50 percent of

in sleep EEG following task acquisition

the night is spent in this stage of sleep.

compared with baseline and control values.





Sleep, Memory, and Dreams

More recently, brain-imaging techniques


Declarative Memory and Sleep

have been used to observe changes in neural activity during postlearning sleep.

Declarative memory consolidation has

A second approach has been to examine

been reportedly enhanced by SWS, partic¬

performance of participants exposed to

ularly episodic memory. Memory for such

postlearning sleep deprivation and com¬

tasks as paired associate words, prose pas¬

pare their performance with those allowed

sages, landscapes, object locations, faces,

normal postacquisition sleep. More re¬

and navigation within virtual or natural en¬

cently, a day-night design has been used

vironments was superior following SWS.

to avoid possible stress confounds. Partici¬

Several studies enhanced memory by ar¬

pants either learn a task in the morning and


are tested 12 hours later with no intervening

activity. Some studies have reported that

sleep or learn the task in the evening and

Stage 2 sleep is also important, with most

are tested 12 hours later in the morning.




observing a postlearning increase in Stage

For this group, a normal night of sleep is in¬

2 spindle activity. REM sleep was also re¬

cluded in the 12-hour time span. The third

portedly involved in a small number of

approach has been to present various kinds of sensory stimulation during postlearn¬ ing sleep to artificially enhance mem¬

declarative learning studies. An imaging study suggests that SWS aids consolida¬ tion of semantic memories as well.

ory consolidation. These methods have all provided evidence for a close relation¬ ship between sleep states and memory

Nondeclarative Memory and Sleep

consolidation (Maquet et al., 2003; Smith,

Skills and habits refer to learning that in¬


cludes such activities as novel perceptual, motor, and cognitive tasks. Acquisition

Emotional Memory

of a visual texture discrimination task re¬ quired both SWS and REM sleep. Efficient

Generally, emotionally charged memories

consolidation of motor tasks, such as the

are better consolidated after REM sleep

finger-tapping sequence task and visuo-

than after NREM sleep. However, while

motor tasks, like the rotary pursuit task,

emotionally positive material is vulnera¬

appear to involve Stage 2 sleep, although

ble to REM-sleep loss, emotionally nega¬

REM sleep has also been implicated. The

tive material is not. A brain-imaging study

type of sleep involved appears to depend

suggests that the negatively charged ma¬

on the initial skill level of the participant.

terial can be consolidated by an alternate

In the rotary pursuit task, participants with

neural route if necessary. The results in¬

low initial skill levels showed postlearn¬

dicate an alternate system for memorizing

ing increases in REM sleep, while partici¬

extremely important survival information

pants with high initial skill levels showed

in case sleep becomes impossible for the

postlearning increases in Stage 2 sleep pa¬

organism following a traumatic natural

rameters. It has been suggested that indi¬


viduals were using one of two overlapping




Sleep, Memory, and Dreams

consolidation systems. Those that found

declarative tasks appear to be enhanced by

the task to be novel and were required to

postlearning sleep, it does not seem as vital

come up with a new cognitive strategy

for procedural tasks.

showed increases in REM-sleep parame¬

The recall rate for children is much

ters (such as minutes of REM sleep, den¬

lower than for young adults. For example,

sity of actual REMs). Those that found the

children age 9 to 11 have a recall rate of

task to be similar to other activities that

20 to 30 percent from REM awakenings

they already had learned, showed increases

and only 6 percent from NREM awak¬

in Stage 2 sleep parameters (such as min¬

enings. Dream reports are less mature in

utes of Stage 2, density, and average size of

children and appear to mirror cognitive

sleep spindles). This idea is consistent with

development. No dreams have been col¬

the finding that cognitively more complex

lected in a formal experimental paradigm

tasks, novel to the learner, require REM

following successful acquisition of a task

sleep for most efficient memory consoli¬

in young children. However, given that the

dation (Smith, Aubrey, & Peters, 2004).

dreams are quite immature at young ages, while ability to learn many tasks is possi¬

Dreams and Sleep States

ble, it would seem unlikely that dreams are necessary for learning (Domhoff, 2010).

A dream can be defined as mental activity reported on awakening from a sleep state. Traditionally, dreams were considered to occur primarily during REM sleep. More

Dream Content Following Task Acquisition

recently, it has become clear that menta¬

There are not many studies that have ex¬

tion can be reported from NREM awaken¬

amined the dream content of post-training

ings as well, although the probability of

sleep. Most studies examined the dreams

obtaining a report (approximately 50%) is

in post-training REM sleep or looked at the

less likely than from REM sleep (80% to

mentation at sleep onset.

90%). REM reports may be more salient as

Several studies asked subjects to play the

well. It is generally agreed that sleep men¬

Tetris computer game, where shapes fall

tation reports reflect the ongoing life of the dreamer.

down the screen and must be manipulated

Since children are learning a multi¬

ened just after sleep onset reported seeing

tude of things from a very young age, it

the pieces falling. Similar results were ob¬

might be expected that their dreams would

tained using a downhill skiing simulator

reflect this activity during postlearning

(Alpine Racer). There was little evidence

sleep. However, the dreams of young chil¬

of episodic replay mentation from either

dren are less well developed than those of

task. Subjects did not recall the room, the

adults. Firstly, sleep states do not seem as

experimenter, or other facets of the lab.

closely related to memory consolidation in

Since one group in the first experiment was

young children compared to adults. While

amnesic (temporal lobe damage), yet still

to fit into a structure. Participants awak¬

Sleep, Memory, and Dreams


experienced postgame Tetris piece menta¬

task. In a second study, using the same

tion, it was concluded that the mentation

experimental paradigm, subjects were ex¬

was from a semantic rather than an epi¬

posed to another cognitive procedural task

sodic source. This idea was consistent with

(mirror trace). Participants had to draw

the results of another study reporting only

pencil lines inside the margins of complex

1 to 2 percent of dreams actually replayed

figures by watching their hand in the mir¬

waking experience.

ror. Dream length was found to be signifi¬

For REM-sleep mentation, one study ex¬

cantly longer for the test group compared

amined the dreams of individuals habitu¬

to control groups, although time spent in

ated to functioning with inverted prisms on.

REM sleep was equal for all groups. It was

While there were few direct incorporations

considered possible that the dreams were

of this experience there was indirect meta¬

more intense for the test group. The most

phorical content. For example, “I wanted to

popular dream metaphor was reference to

know what it was. Then I looked at a word,

driving cars and trying to stay on the road.

but it was upside down.” The dreams usu¬

Dreams generally reflected the problem of

ally reflected increases in visual and motor

staying on a road or path. There was virtu¬

difficulties. In another study, participants

ally no episodic replay observed (Smith,

were exposed to second language learning.


All students were in a French immersion

In summary, sleep mentation appears to

environment for several weeks. Learning

reflect memory consolidation activity in

progress was correlated with increased

certain situations. Present evidence does

time in REM sleep. For dream content, the

not provide support for the idea that sleep

more progress the student made, the shorter

mentation aids memory consolidation. Carlyle Smith

was the latency to French incorporations and communications.

Students making

minimal progress did not report any French incorporations in their dreams. In a memory-enhancement study, par¬ ticipants were trained in a cognitive pro¬ cedural task. A clicking sound was present in the background during acquisition and acted as the conditioned stimulus (CS). Dur¬ ing the postlearning sleep night, they were subjected to the CS via mini-earphone. The clicks were triggered by maximum deflec¬ tion of actual rapid eye movements during REM sleep. Test subjects were 23 percent better than controls. The clicks were be¬ lieved to have acted as reminders to re¬ member to process the recently acquired

See also: Sleep and Mild Cognitive Impairment References Domhoff, G. W. (2010). Dream content is con¬ tinuous with waking thought, based on pre¬ occupations, concerns, and interests. Sleep Medicine Clinics, 5, 203-215. Maquet, P., Smith, C., & Stickgold, R. (2003). Sleep and brain plasticity. Oxford: Oxford University Press. Smith, C.T. (2010). Sleep states, memory pro¬ cessing and dreams. Sleep Medicine Clinics, 5, 217-228. Smith, C.T., Aubrey, J.B., & Peters, K.R. (2004). Different roles for REM and Stage 2 sleep in motor learning: A proposed model. Psychologica Belgica, 44, 81-104.




Sleep, Nightmares, and Psychiatry

sleep time. More interestingly, reduced

Sleep, Nightmares, and Psychiatry

REM-sleep latency was identified as an objective indicator of depressive disorder and an inverse correlate of its severity. Re¬

Sleep and circadian rhythms are strongly

duced REM latency has proved to be one of

related to physical and mental health. Sleep

the specific features of sleep in depressed

disturbances and circadian changes affect

patients. Other reported abnormalities in

body functions as well as mood and cog¬

REM sleep include a prolonged duration of

nitions. Sleep abnormalities are very com¬

the first REM period, an increased density

mon in psychiatric disorders, in particular,

of eye movements, and an increased REM

in mood disorders and anxiety disorders.

percentage of total sleep time. Slow-wave

This is because hormonal changes in body

sleep time is also reduced in depressed pa¬

and monoaminergic dysregulations in the

tients than healthy subjects. Among en¬

central nervous system are described both

dogenous depressive symptoms, terminal

in sleep disorders and in mood/anxiety

insomnia, pervasive anhedonia, unreactive

disorders. Thus, sleep disturbances and

mood, and appetite loss are reported to be

dreaming disorders are one of the central

related to short REM latency in depressed

issues of depression and anxiety disorders.


Insomnia is common among typical de¬

Anxiety is commonly related to sleep

pressed patients. On the other hand, hyper¬






somnia often occurs in atypical depressive

frequent in patients with panic disorder.

patients, bipolar depressed patients, and

Approximately one third of patients with

adolescent depressives. Depressed patients

panic disorder reports recurrent sleep

often report difficulty in falling sleep,

panic. Interestingly, recurrent sleep panic

maintenance problems of sleep, and early

is correlated with suicidality and depres¬

awaking, named as initial, middle, and ter¬

sion among panic disordered patients.

minal insomnia, respectively. Sleep distur¬

Posttraumatic stress disorder and other

bances may have prognostic significance

anxiety disorders are also associated with

in predicting suicide among patients with

sleep-pattern changes.

mood disorders. Among objective mark¬

Nightmares are long frightening dreams

ers of sleep abnormalities in depression,

involving threats to survival or security,

reduced REM-sleep latency was identified

from which the sleeper awakens, and

as an objective indicator of depressive dis¬

should be distinguished from sleep terrors,

order and an inverse correlate of its sever¬

narcolepsy, sleep panic attacks, and other

ity. Reduced REM latency has proved to be

awakenings. Nightmares typically occur

one of the robust and specific features of

later in the night during REM sleep and

sleep in depressed patients. Other reported

produce vivid dream imagery, complete

abnormalities in REM sleep include a pro¬

awakenings, autonomic arousal, and de¬

longed duration of the first REM period,

tailed recall of the event and may cause

an increased density of eye movements,

psychological distress and social or occu¬

and an increased REM percentage of total

pational dysfunction.

Sleep Pattern and Its Determining Factors in University Students


Recurrent nightmares may be associated

self. Smoking, caffeine, and alcohol intake

with a high comorbidity of mood and anxi¬

increase it. Several disorders may be re¬

ety disorder, in particular in young adults

sponsible for causing nocturnal violence:

and adults. Frequent nightmares and termi¬

sleepwalking, sleep terrors, REM sleep

nal insomnia are common in melancholic

behavior disorder, nocturnal psychogenic


dissociative disorders, nocturnal seizures,

The association of dream disturbances with ?ashbacks related to the trauma sug¬ gests that nightmares appear to be an effec¬ tive coping mechanism in trauma victims. A relationship between dream anxiety and

obstructive sleep apnea, and periodic limb movement disorder. Mehmed Y. Agargun

See also: entries related to Sleep and Health

dissociative experiences and the causal role of childhood traumatic events may play a role in this relationship. Nightmare disorder seems to be associ¬ ated with self-mutilation, suicidal behav¬

Sleep Pattern and Its Determining Factors in University Students

ior, and borderline personality. It may be reasonable to attribute a role to nightmares

Sleep patterns of university students are

as an adaptive coping strategy in dissocia¬

likely to become delayed and irregular. A

tive disorders and borderline personality

considerable number of students meet the

disorder. The dreams reduce the inten¬

diagnostic criteria for delayed sleep-phase

sity of the emotional distress by juxtapos¬

syndrome (DSPS), which is characterized

ing the current trauma with various other

by delayed habitual sleep-wake time rela¬

events in the person’s life, making con¬

tive to desired and socially acceptable time

nections to other similar or not-so-similar

(Hazama, Inoue, Kojima, Ueta, & Naka-

events. When trauma is dreamt about, it is

gome, 2008). Because the sleep phase is

no longer uniquely distressing; it gradu¬

prone to delay with advancing age during

ally becomes part of a fabric or network.

adolescence, the remarkable phenomenon

Thus, dreaming has an adaptive function

of sleep-phase delay in university students

and nightmares are common following a

could reflect the maturational process

trauma. Thus, we suggest that nightmares

of biological rhythms. However, a lon¬

are useful dreams to cope with the conflicts

ger delay in the sleep pattern is observed

of traumatic events, if they are worked on

among university students than among

appropriately in therapy.

nonuniversity students of the same age,

Sleep-related violence is also a popular

such as workers. Since the sleep-wake

topic. It has forensic importance as well as

phase of students is dramatically delayed

clinical interest. Violent behavior during

shortly after they enter the university, we

sleep includes a broad range of behaviors:

believe that milder regulation of sched¬

self-mutilation, sexual assault, murder at¬

ules and restrictions by the university than

tempt, murder, and suicide and can be di¬

those by high school might contribute to

rected to other subjects, to objects, or to

the delayed sleep patterns.




Sleep Pattern and Its Determining Factors in University Students

Similar to other cohorts, the amount of

rather than the total sleep duration, has a

nocturnal sleep in university students has

stronger effect on their academic perfor¬

decreased by more than an hour in the last

mance. A delayed bed off time, in particular,

few decades. Steptoe, Peacey, and Wardle

showed a strong association with poor aca¬

(2006) surveyed the sleep pattern of uni¬

demic performance (Eliasson, Lettieri, &

versity students in 24 countries and showed

Eliasson, 2010), and therefore, low GPA

that 21 percent of the students were con¬

could be a result of absence from morning

sidered short sleepers with less than seven

classes, which is attributable to the delayed

hours of nocturnal sleep (Steptoe et al.,

sleep phase.

2006). They also suggested a relationship

Factors influencing the sleep pattern of

between short sleep and poor health. A

university students have been discussed in

survey conducted on a large population of

many studies. These studies showed that

university students revealed that more than

students’ sleep patterns vary depending

60 percent of the study population had poor

on their nationality, academic year, and

sleep quality, which was measured using

their resident status, that is, whether they

the Pittsburgh Sleep Quality Index (Lund,

lived with or without their family. Univer¬

Reider, Whiting, & Prichard, 2010). As ex¬

sity students in Asian countries (Steptoe

pected, the inadequate sleep time and ir¬

et al., 2006) and senior students (Asa-

regular/delayed sleep pattern was likely to

oka, Fukuda, & Yamazaki, 2004; Hazama

be related to poor sleep quality. In addition,

et al., 2008) have specifically been reported

their poor sleep quality also led to various

with poor sleep habits. A study using sleep

daytime malfunctions such as increased

logs showed that students who lived alone

depression-like symptoms and irritabil¬

had a more delayed sleep phase on week¬

ity, disturbed concentration, and daytime

days than those who lived with their fam¬

sleepiness, all of which possibly lead to

ilies (Asaoka et al., 2004). In this study,

students dozing off while attending classes

there was no difference between these two

or driving. The deterioration of academic

groups in terms of the sleep phase on week¬

performance, that is, low grade point aver¬

ends, and the students living with their

age (GPA), is also related to the students’

family had a longer commuting time than

poor sleep habits. Many studies have sug¬

those living alone. Thus, existence of fa¬

gested that inadequate sleep causes a de¬

milial time cue and longer commuting time

crease in cognitive performance such as

for the students who live with their fam¬

the learning-memory process, which is es¬

ily might be responsible for the early sleep

sential for maintaining good academic per¬

phase in this group of students.

formance (Curcio, Ferrara, & De Gennaro,

Daily activities such as watching televi¬

2006). It is speculated that the decrease

sion (TV), surfing the Internet, playing vid¬

in cognitive performance and the dozing

eogames, attending classes, and working

off during classes due to inadequate night

part-time are also known determinants of

sleep lead to a low GPA. Moreover, inter¬

sleep pattern. Many studies have suggested

estingly, some studies have suggested that

a relationship between the sleep pattern and

among university students, the sleep phase,

these activities, especially during the night.

Sleep Pattern and Its Determining Factors in University Students


However, the extent to which each activity

cross-sectional questionnaires. Therefore,

affects sleep patterns remains unknown. A

the causal relationships between the pre¬

study that investigated this issue in Japa¬

viously mentioned variables and students’

nese students through a time-use survey

sleep patterns are still unclear, despite the

(Asaoka et al., 2010) showed that the in¬

various studies. An intervention study was

fluence of the daily activities on the stu¬

recently carried out, in which the dura¬

dents’ sleep patterns differed between the

tion of watching TV was restricted to 30

students living alone and those living with

minutes or less per day for the univer¬

their families. Among the students living

sity students (Asaoka, Fukuda, Tsutsui, &

alone, inteipersonal communication late

Yamazaki, 2007). The results showed that

at night was most prominently associated

they went to bed 26 minutes earlier than

with delayed bedtime. In addition, their

their usual bedtime and increased their

sleep patterns seemed to change depending

total nocturnal sleep time by 69 minutes;

on the whether or not they had a class the

however, their morning physical activity

next morning. On the other hand, students

declined after the intervention. This find¬

who lived with their family did not show

ing suggests that watching TV may be one

change in their sleep patterns irrespective

of the important factors for delayed bed¬

of their class schedules, and their sleep pat¬

time, but it may also play a role as a so¬

tern was affected mainly by indoor activi¬

cial time cue for maintaining regular sleep

ties such as watching TV and surfing the

patterns, which help in maintaining their

Internet. Although the differences between

circadian rhythm. Future studies should be

the two groups might partially depend on

conducted to confirm whether restriction

the existence/absence of familial time cue,

of other nocturnal activities such as surf¬

further study is required to clarify the un¬

ing the Internet is helpful in both increas¬

derlying cause of this phenomenon.

ing students’ sleep duration and preventing

A good sleep pattern is an important

a delay in their bedtime.

factor for university students to maintain

Apart from the restrictions on nocturnal

not only good health but also a good aca¬

activities, education on good sleep habits

demic life, and hence, it is essential that

is also essential to improve students’ sleep

their bedtime is not delayed. Previous stud¬

habits. A previous study reported that a

ies have suggested that restricting the use

sleep education program that included

of visual media and socializing activities

sleep-hygiene guidelines, stimulus-control

at night could be effective in preventing

instructions, and information about caf¬

the sleep-phase delay. Moreover, a revi¬

feine products improved the sleep quality

sion of university schedules, such as the

of the study participants (Brown, Buboltz,

intensive morning schedules, may help

& Soper, 2006). Concurring with the phe¬

in maintaining early bedtime, especially

nomenon that sleep-deprived subjects can¬

for the students living alone. However,

not comprehend a decrease in the quality

most studies .exploring the relationship be¬

and quantity of their daily tasks, most uni¬

tween students’ sleep pattern and the de¬

versity students with poor sleep habits are

terminant factors were conducted by using

unaware of the fact that their poor academic




Sleep Patterns in Patients with Acute Coronary Syndromes

performance is a result of their disturbed

academic performance. Sleep Medicine Re¬

sleep patterns. In addition, a certain pro¬

views, 10, 323-337.

portion of university students adopt irra¬ tional countermeasures for their deficient nocturnal sleep. For example, students try to compensate their sleep deficit by tak¬ ing long daytime naps and/or prolonging their nocturnal sleep until the afternoon on weekends. Such behavior can disturb their sleep-wake rhythms, and possibly result in circadian-rhythm sleep disorders, especially DSPS. Therefore, sleep educa¬ tion that includes rational knowledge and the effects of sleep on the academic life and health of university students would be desirable. Shoichi Asaoka and Yuichi Inoue

See also: entries related to Sleep and Devel¬

Eliasson, A. H., Lettieri, C. J., & Eliasson, A. H. (2010). Early to bed, early to rise! Sleep habits and academic performance in college students. Sleep and Breathing, 14, 71-75. Hazama, G.I., Inoue, Y., Kojima, K., Ueta, T., & Nakagome, K. (2008). The prevalence of probable delayed-sleep-phase syndrome in students from junior high school to univer¬ sity in Tottori, Japan. The Tohoku Journal of Experimented Medicine, 216, 95-98. Lund, H.G., Reider, B.D., Whiting, A.B., & Prichard, J.R. (2010). Sleep patterns and predictors of disturbed sleep in a large pop¬ ulation of college students. Journal of Ado¬ lescent Health, 46, 124-132. Steptoe, A., Peacey, V., & Wardle, J. (2006). Sleep duration and health in young adults. Archives







References Asaoka, S., Fukuda, K., Tsutsui, Y., & Yamazaki, K. (2007). Does television viewing cause delayed and/or irregular sleep-wake patterns? Sleep and Biological Rhythms, 5, 23-27.

Sleep Patterns in Patients with Acute Coronary Syndromes

Asaoka, S., Fukuda, K., & Yamazaki, K. (2004). Effects of sleep-wake pattern and residential status on psychological distress in university students. Sleep and Biological Rhythms, 2, 192-198.

Sleep is essential for several restorative,

Asaoka, S., Komada, Y., Fukuda, K., Sugiura, T., Inoue, Y., & Yamazaki, K. (2010). Ex¬ ploring the daily activities associated with delayed bedtime of Japanese university stu¬ dents. The Tohoku Journal of Experimental Medicine, 221, 245-249.

metabolic, and immunologic functions. Restful sleep requires a normal sleep macro- and micro-architecture. There is plentiful scientific evidence to support the fact that sleep disruption leads to unde¬ sirable consequences (Banks & Dinger, 2007), especially for critically ill patients. Sleep disruption with acute quantitative or qualitative sleep deprivation, which has

Brown, F.C., Buboltz, W.C., Jr., & Soper, B. (2006). Development and evaluation of the Sleep Treatment and Education Program for Students (STEPS). The Journal of American College Health, 54, 231-237.

been studied mainly in healthy subjects,

Curcio, G., Ferrara, M., & De Gennaro, L. (2006). Sleep loss, learning capacity and

et al., 1999), endocrine and metabolic func¬

may impair physiological functions impor¬ tant for recovery, including tissue repair, overall cellular immune function (Oztiirk tions (Spiegel, Leproult, & Van Cauter,

Sleep Patterns in Patients with Acute Coronary Syndromes


1999), and energy balance (Scrimshaw

cycle. Methods used to assess sleep include

et al., 1966). In addition it can induce sym¬

bedside inspection, patient’s perception,

pathetic activation and elevation of blood


pressure (Leung & Bradley, 2001), which

phy. Attended overnight PSG remains the

may contribute to patient morbidity. It is

gold standard for sleep evaluation, but

not difficult to imagine that an individual

entails several technical difficulties and

who has already become ill and requires

limitations when performed in the ICU

hospitalization, such as a patient with acute

environment, especially in patients recov¬

coronary syndrome, should be more vul¬

ering from critical illness. There are a num¬

nerable to medical problems when sleep is

ber of studies evaluating sleep in critically

disrupted. Research into the role of sleep

ill patients, some involving polysomno-

and the effects of sleep deprivation in criti¬

graphic recordings over 24 hours (Cooper

cally ill patients has been limited by con¬

et al., 2000; Freedman et al., 2001; Gabor

founding factors that make it difficult to

et al., 2003), others with polysomnographic

quantify and isolate the effects of sleep on

recordings during nighttime alone (Aaron

clinical recovery.

et al., 1996; Broughton & Baron, 1978;




Sleep disruption in the intensive care

Richards, Anderson, Chesson, & Nagel,

unit (ICU), including the coronary care

2002), and studies without polysomno¬

unit (CCU), is a well-recognized phe¬

graphic recordings (Olson et al., 2001;

nomenon that can have important adverse

Nelson et al., 2001). Investigators differ in

consequences for the critically ill patient.

their conclusions as to whether critically ill

Patients experience severe alterations of

patients are sleep deprived, reporting large

sleep, with sleep loss, sleep fragmenta¬

variations in total sleep time among pa¬

tion, and sleep-wake cycle disorganiza¬

tients in the ICU. Some studies found that

tion. Many factors may contribute to these

critically ill patients have a normal or near



normal total sleep time (Cooper et al., 2000;

factors such as noise, patient care activi¬

Freedman et al., 2001), while other investi¬

ties, disturbed light-dark cycle, medica¬

gators found a decrease in total sleep time

tions (sedatives and inotropes), therapeutic

(Gabor et al., 2003). The different findings

and diagnostic procedures, and mechani¬

among these studies may be due to different

cal ventilation (Hardin, 2009); however,

populations with different underlying med¬

the contribution of each factor is not clear.

ical and surgical problems, small groups of

The severity of the underlying disease is

patients, or interference with the natural en¬

likely to be an important factor and needs

vironment or routine treatment in ICU.


The quality and distribution of sleep

to be determined. Sleep can be assessed in terms of quan¬

over 24 hours are also affected, even in

tity (total sleep time and time spent in each

ICU hospitalized patients who have nor¬

sleep stage), quality (fragmentation due

mal total sleep time. About half of total

to micro-arpusals,

sleep-stage changes,

sleep time occurs in the daytime and the

wake after sleep onset, EEG sleep pat¬

circadian rhythm is markedly impaired

terns), and distribution over the 24-hour

(Cooper et al., 2000; Gabor et al., 2003).




Sleep Patterns in Patients with Acute Coronary Syndromes

Critically ill patients exhibit more frequent

were no sudden changes in sleep archi¬

arousals and awakenings than normal. The

tecture after transfer to the general ward.

degree of sleep fragmentation is at least


equivalent to that seen in patients with ob¬

patient-care activities, and disturbances of

structive sleep apnea (Guilleminault et al.,

the light-dark exposure to sleep disruption

1988). Additionally, an impairment in the

in the CCU and general ward were not ad¬

distribution of sleep stages has been rec¬

dressed specifically. Sleep abnormalities

ognized. Critically ill patients spent less

improved gradually over time with trans¬

of their sleep time in rapid eye movement

fer to the hospital ward, even though nor¬

(REM) sleep or in Stages 3 and 4, known

mal sleep patterns were not restored in

as slow-wave (SWS) or deep sleep, which

patients with acute MI until nine days after

is considered the most restorative type

discharge from the ICU. The altered sleep

of sleep (Cooper et al., 2000; Freedman

patterns were largely attributed to the in¬

et al., 2001). Factors disturbing sleep,

farction itself. However, subsequent angi¬

such as noise, may result in electroen-

nal attacks peaked at day 4 to day 5 and

cephalographic arousals and awakenings,

occurred more often during REM sleep.

which may not only affect sleep micro¬

Similar results were obtained by Dohno

architecture but prevent the normal prog¬

et al. (1979), who observed sleep disrup¬

ress into deeper sleep stages (Carskadon &

tions regardless of type of unit, length

Dement, 2005). This disturbed sleep pat¬

of hospitalization, gender, or medica¬

tern may take several days to normalize

tions in coronary patients in an open-

after discharge from the ICU.

ward CCU and in a semiprivate telemetry



of noise,

There is little knowledge about sleep

unit (Dohno et al., 1979). Moreover, they

quality impairment in patients admitted to

found that patients in the greater severity-

the CCU with acute coronary syndromes

of-illness group, as judged by a cardiolo¬

(ACS). Early studies of patients in coro¬

gist, had more nocturnal awakenings and

nary care after acute myocardial infarction

more sleep-stage changes, consistent with

(MI), 30 years ago, had already recognized

greater sleep fragmentation, than a compa¬

disturbed sleep architecture but suggested

rable group with lesser severity of illness,

increased total sleep time (TST; Brough¬

indicating that severity of illness may turn

ton & Baron, 1978; Dohno et al., 1979).

out to be a very important cause of sleep

Broughton et al., reported findings in 12

disturbance in ICU patients.

patients after an acute MI who underwent

In a more recent study, Ahmed BaHam-

overnight PSGs in the ICU and thereafter

mam evaluated the sleep quality of 20 pa¬

in the ward, comparing them to matched

tients with acute MI within three days of

controls (Broughton & Baron, 1978). The

the acute event and six months later, in the

results were similar to other ICU patients,

sleep disorder center, outside the CCU en¬

with increased wakefulness, more arous¬

vironment (BaHammam, 2006). Despite

als and sleep-stage shifts, a low percentage

controlling for common sleep-disrupting

of REM sleep, and an absence of the usual

environmental factors, patients with AMI

circadian variation in heart rate. There

had altered sleep architecture. Arousal

Sleep Patterns in Patients with Acute Coronary Syndromes


index, spontaneous arousals, stage shifts,

The findings of the previously mentioned

REM latency, and wake time were signifi¬

studies highlight the major contribution of

cantly greater, while TST, sleep efficiency,

the illness severity and associated physi¬

and (REM) sleep were significantly less

ological and inflammatory changes to al¬

during the acute event compared with six

terations in sleep architecture and deserve

months later, findings that are in accor¬

further research. The expression of many

dance with previous studies. The authors

cytokines is unregulated in healing myo¬

concluded that factors other than the CCU

cardial infarcts (Frangogiannis & Entman,

environment, patient care activities, me¬

2005), with inflammatory cytokines hav¬

chanical ventilation, and medications are

ing both somnogenic and sleep-inhibitory

involved in sleep disruption, such as the

effects, and it has been reported to influ¬

underlying infarction itself. However, this

ence sleep and sleep depth (Krueger et al.,

study did not objectively assess the pos¬

1995). It is known that proinflammatory

sible influence of circadian-rhythm dis¬

cytokines, such as interleukin-1 (IL-1),

turbances, while the patients studied were

IL-6, and tumor necrosis factor-alpha, are

heterogeneous with respect to concomitant

released after MI (Deten & Zimmer, 2002;

sleep disorders, such as sleep-breathing

Francis et al., 2004). It is worth noting that

disorders, restless legs syndrome (RLS),

a recent study demonstrated that MI in

and periodic limb movement disorder

rats is associated with the release of fac¬

(PLMD). The most recent study from our

tors that provoke the inflammation of tis¬

group assessed 22 patients with first ever

sues, including the brain, and specifically

ACS, who were not on sedation or inotro-

the regions that control sleep, notably the

pes, with attended overnight PSG in the

REM-sleep phase (Bah et al., 2010). The

sleep disorders unit within three days of the

authors reported decreased REM-sleep

ACS and one and six months later (Schiza

time, comparable with what has been ob¬

et al., 2010). This was the first study ob¬

served in patients after MI (BaHammam,

jectively controlled for circadian-rhythm

2006; Dohno et al., 1979; Leung & Brad¬

disturbances and selected patients with¬

ley, 2001; Schiza et al., 2010), which could

out concomitant diseases that could affect

be associated with a reduced number of

sleep architecture, such as RLS, PLMD,

brain stem neurons. However, the mech¬

and current smoking. In accordance with

anisms by which brain stem neurons are

the BaHammam study, TST, sleep ef¬

lost after MI are unclear and need further

ficiency, SWS, and REM sleep were

investigation. One possibility is that pro-

significantly reduced and a significant im¬

inflammatory cytokines could be involved

pairment in sleep micro-architecture was

in the decreased post-MI duration of REM

noted due to an increased arousal index,

sleep reported here, through apoptosis in

during the acute event. Sleep architecture

the cholinergic neurons in the brain stem,

was improved one month later, while six

which control REM sleep. This study indi¬

months after,the acute event sleep duration

cates that the damaging effects of MI are

as well as sleep stages were within the nor¬

apparently not confined to the heart, but

mal ranges.

also affect the brain. Furthermore, it might




Sleep Patterns in Patients with Acute Coronary Syndromes

provide useful data related to the associa¬ tion between cardiac pathophysiology and sleep alterations in such patients. It seems likely that sleep is important to the recovery process as an integral homeo¬ static mechanism. Indeed, it is well known that sleep plays a crucial role in postinfarc¬ tion remission. Quality rather than quan¬ tity of sleep should be our primary target in the management of sleep disruption in ACS. Any preventive, pharmacological, or behavioral treatment is certainly a path¬ way that should be considered. However,

Bah, T. M., Laplante, F., Wann, B. P., Sullivan, R., et al. (2010). Paradoxical sleep insom¬ nia and decreased cholinergic neurons after myocardial infarction in rats. Sleep, 7(33), 1703-1710. BaHammam, A. (2006). Sleep quality of pa¬ tients with acute myocardial infarction outside the CCU environment: A prelimi¬ nary study. Medical Science Monitor, 12, 168-172. Banks, S., & Dinger, D.F. (2007). Behavioral and physiological consequences of sleep re¬ striction. Journal of Clinical Sleep Medi¬ cine, 3, 519-528.

enhance the quantity and quality of sleep

Broughton, R., & Baron, R. (1978). Sleep pat¬ terns in the intensive care unit and on the ward after acute myocardial infarction.

during recovery from critical illness or

Electroencephalography and Clinical Neu¬

injury are lacking. It remains to be deter¬

rophysiology, 45, 348-360.

research into the effects of protocols that

mined whether improving sleep will have an impact on ACS. In conclusion, sleep in patients with

Carskadon, M.A., & Dement, W.C. (2005). Normal human sleep: An overview. In M. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practice of sleep medicine

ACS poses unique challenges for patients,

(pp. 13-23). Philadelphia, PA: WB Saunders.

clinicians, and researchers. These patients

Cooper, A. B., Thornley, K. S., Young, G.B., Slutsky, A. S., et al. (2000). Sleep in criti¬ cally ill patients requiring mechanical ven¬ tilation. Chest, 117, 809-818.

experience severe sleep alterations, with reductions in several sleep stages, marked sleep fragmentation, and circadian-rhythm disorganization. The impact of these acute sleep alterations on the health of ICU pa¬ tients remains unknown. These effects may delay recovery and decrease the chances for a positive outcome, but it remains to be determined if improving sleep will have an impact on patients with ACS. Sophia E. Schiza

See also: entries related to Sleep Disorders References Aaron, J.N., Carlisle, C.C., Carskadon, M. A., Meyer, T.J., et al. (1996). Environmental noise as a cause of sleep disruption in an in¬ termediate respiratory care unit. Sleep, 19, 707-710.

Deten, A., & Zimmer, H.-G. (2002). Heart function and cytokine expression is similar in mice and rats after myocardial infarction but differences occur in TNFalpha expres¬ sion. Pflugers Archives, 445, 289-296. Dohno, S., Paskewitz, D. A., Fynch, J.J., Ken¬ neth, S., et al. (1979). Some aspects of sleep disturbance in coronary patients. Perceptual and Motor Skills, 48, 199-205. Francis, J., Chu, Y., Johnson, A. K., Weiss, R.M., et al. (2004). Acute myocardial in¬ farction induces hypothalamic cytokine synthesis. American Journal of Physiology Heart and Circulatory Physiology, 286,

H2264-H2271. Frangogiannis, N. G„ & Entman, M. F. (2005). Chemokines in myocardial ischemia. Trends in Cardiovascular Medicine, 15, 163-169.

Sleep, Plasticity, and Metaplasticity

Freedman, N.S., Gazendam, J., Levan, L., Pack, A. I., et al. (2001). Abnormal sleep/ wake cycles and the effect of environmen¬ tal noise on sleep disruption in the intensive care unit. American Journal of Respiratory and Critical Care Medicine, 163, 451-457. Gabor, J.Y., Cooper, A.B., Crombach, S.A., Lee, B., et al. (2003). Contribution of the intensive care unit environment to sleep dis¬ ruption in mechanically ventilated patients and healthy subjects. American Journal of Respiratory and Critical Care Medicine, 167, 708-715.

Guilleminault, C., Partinen, M., Quera-Salva, M. A., Hyes, B., et al. (1988). Determinants of daytime sleepiness in obstructive sleep apnea. Chest, 94, 32-37. Hardin, K. A. (2009). Sleep in the ICU: Poten¬ tial mechanisms and clinical implications. Chest, 136, 284-294. Krueger, J.M., Takahashi, S., Kapas, L., Bredow, S., et al. (1995). Cytokines in sleep regulation. Advances in Neuroimmunology, 5, 171-188. Leung, R. S., & Bradley, T.D. (2001). Sleep apnea and cardiovascular disease. American Journal of Respiratory and Critical Care Medicine, 164, 2147-2165.

Nelson, J. E., Meier, D. E., Oei, E. J., Nierman, D. M., et al. (2001). Self-reported symptoms experience of critically ill cancer patients re¬ ceiving intensive care. Critical Care Medi¬ cine, 29, 277-282. Olson, D. M., Borel, C.O., Laskowitz, D.T., Moore, D.T., et al. (2001). Quiet time: A nursing intervention to promote sleep in neurocritical care units. American Journal of Critical Care, 10, 74-78. Oztiirk, L., Pehn, Z., Karadeniz, D., Kaynak, H., et al. (1999). Effects of 48 hours sleep deprivation on human immune profile. Sleep Research Online, 2, 107-111. Richards, K.€., Anderson, W.M., Chesson, A.L., & Nagel, C.L. (2002). Sleep related breathing disorders in patients who are


critically ill. Journal of Cardiovascular Nursing, 17, 42-55.

Schiza, S.E., Simantirakis, E., Bouloukaki, I, Mermigkis, C., et al. (2010). Sleep patterns in patients with acute coronary syndromes. Sleep Medicine, 11, 149-153. Scrimshaw, N.S., Habicht, J.-P., Pellet, P., Piche, M.L., et al. (1966). Effects of sleep deprivation and reversal of diurnal activ¬ ity on protein metabolism of young men. American Journal of Clinical Nutrition, 19,

313-319. Spiegel, K., Leproult, R., & Van Cauter, D. (1999). Impact of sleep dept on meta¬ bolic and endocrine function. Lancet, 354, 1435-1439.

Sleep, Plasticity, and Metaplasticity Throughout a lifetime of experience, our knowledge base and skills continue to evolve in a dynamic and flexible way. Fun¬ damentally, such information storage and memory is represented in the brain by the strength of the connections, or synapses, between neurons within neuronal circuits. When synapses are strengthened, commu¬ nication is enhanced, and neural activity generates stronger responses in connected neurons; when synapses are weakened, the evoked responses in connected neu¬ rons are reduced. Plasticity is a term used to describe these changes in the strength of neural connections as a result of experi¬ ence. Metaplasticity reflects the regulation of plasticity, or a shift in the capacity for a synapse to undergo future plasticity based on its recent history (Abraham, 2008). A growing body of literature suggests that sleep may engage processes of plastic¬ ity. Plasticity is not a unitary phenomenon,




Sleep, Plasticity, and Metaplasticity

taking many different forms and reflect¬

signal-to-noise ratio can have a benefit on

ing diverse molecular and cellular mecha¬

memory recall. These models are not mu¬

nisms. Similarly, sleep is not a homogenous

tually exclusive, potentially reflecting si¬

state, encompassing distinct stages and a

multaneous and complementary processes.

variety of electrophysiological processes.

The relationship between metaplasticity

The complexity of these physiological

and sleep has not been well studied, with

processes suggest that there may be mul¬

only one recent study in humans (Cohen

tiple mechanisms linking sleep and plas¬

et al., 2010). That study used noninvasive

ticity, potentially explaining the difficulty

brain stimulation to induce plasticity in the

in establishing a unified conceptual frame¬

motor cortex, evidenced by the change in

work to reconcile conflicting findings in

the size of evoked motor responses mea¬

the sleep and memory literature (Rauchs,

sured in the hand. Each participant had

Desgranges, Foret, & Eustache, 2005). In

two plasticity-induction sessions spaced

recent years, two dominant models in the

12 hours apart, either over day or over¬

field have emerged. The first model in¬

night. This study demonstrated that a night

volves reactivation or replay during sleep

with sleep was associated with a twofold

of neuronal firing patterns experienced

increase in the magnitude of the evoked

during recent wakefulness. For example,

motor response in the second session com¬

sequences of neuronal activity patterns re¬

pared to the first. In contrast, in the over¬

corded from different brain areas of rats

day group, the degree of induced plasticity

while they are learning to navigate a maze

was the same for both sessions. In other

show coordinated replay during subsequent

words, a night with sleep enhanced the ca¬

slow-wave sleep (Ji & Wilson, 2007). Such

pacity for the brain to undergo subsequent

reactivation or replay can promote a use-

plasticity when the same environmental

dependent strengthening of synaptic con¬

exposure was repeated.





In conclusion, sleep appears to engage

memories for facts, events, and skills.

processes of plasticity to modify existing

The second model is known as the syn¬

knowledge and skills, either through neu¬

aptic homeostasis hypothesis (Tononi &

ronal replay, general synaptic downscaling,

Cirelli, 2003). This model suggests that

or perhaps other mechanisms. In addition,

wakefulness is associated with widespread

sleep may engage processes of metaplas¬

increases in synaptic strength, which taxes

ticity such that synapses may become more

finite space and energy resources in the

responsive to undergo future changes in

brain. Sleep, and in particular slow-wave

response to a given stimulus, perhaps one

sleep, is proposed to cause a general down-

mechanism in which sleep could promote

scaling, or weakening, of synaptic strength

the process of leamihg to learn. A greater

to restore synaptic balance while maintain¬

understanding of how sleep engages the

ing the relative connection strengths. In this

processes of plasticity and metaplasticity

model, the general weakening of connec¬

can have widespread applications from

tions during sleep reduces the background

education and training to rehabilitation of

noise in neural activity, and improved

patients after neurological injury. Future

Sleep Problems among Veterans of Foreign Wars


work should also target the role of the cir¬

impaired functioning of affected individ¬

cadian timekeeping system or its interac¬

uals. We now have a name for one form

tion with sleep state to modulate plasticity.

of the array of postcombat mental prob¬

Daniel Aaron Cohen

lems that affect our veterans. That name of

See also: Sleep, Memory, and Dreams

course is posttraumatic stress disorder, or PTSD. One of the core symptoms of PTSD

References Abraham, W. C. (2008). Metaplasticity: Tuning synapses and networks for plasticity. Nature Reviews Neuroscience, 9(5), 387-399. Cohen, D. A., Freitas, C., Tormos, J.M., Oberman, L., Eldaief, M., & Pascual-Leone, A. (2010). Enhancing plasticity through re¬ peated rTMS sessions: The benefits of a night of sleep. Clinical Neurophysiology, 727(12), 2159-2164. Ji, D., & Wilson, M.A. (2007). Coordinated memory replay in the visual cortex and hippocampus during sleep. Nature Neuro¬ science, 70(1), 100-107. Rauchs, G., Desgranges, B., Foret, J., & Eustache, F. (2005). The relationships between memory systems and sleep stages. Journal of Sleep Research, 74(2), 123-140. Tononi, G., & Cirelli, C. (2003). Sleep and syn¬ aptic homeostasis: A hypothesis. Brain Re¬ search Bulletin, 62(2), 143-150.

is sleep disturbance. PTSD is a major health concern for the Veterans Administration (VA) and the veterans it serves. A 2005 report from the VA’s Office of the Inspector General noted that the number of veterans receiv¬ ing compensation for PTSD between 1999 and 2004 grew to 215,871 cases (Depart¬ ment of Veterans Affairs [DVA], 2005). Review of state variances in VA disability compensation payments (DVA, 2005), and continued increases are likely to have oc¬ curred with the subsequent intensification of the wars in Iraq and Afghanistan. Rates of PTSD diagnoses are likely to dramati¬ cally increase due to the ongoing Iraq/Af¬ ghan wars and indeed due to wars around the world. Surveys show that at least 11 to 17 percent of combat veterans are at risk for mental disorders, including PTSD, in the three to four months after return from

Sleep Problems among Veterans of Foreign Wars

combat duty and probably for much longer periods of time after return. One such sur¬ vey assessed 16,318 Afghan veterans and

People who witness or participate in com¬

222,620 Iraq veterans and found that 19.1

bat are exposed to levels of violence and

percent returnees from Iraq compared with

trauma the rest of us can only imagine. In

11.3 percent returnees from Afghanistan

wars past, very little help was available for

screened positive for mental health prob¬

the veteran who experienced postcombat

lems, including PTSD. Thirty-five per¬

mental and sleep problems. From a policy

cent of Iraq war veterans accessed mental

point of view, this past neglect of postcom¬

health services in the year after returning

bat mental problems was unfortunate, as

home; 12 percent per year were diagnosed

these sorts of problems eventually extract

with a mental health problem. Roughly

a cost to both military effectiveness and

20 percent of active and 42.4 percent of re¬

civilian economic performance due to the

serve component soldiers required mental




Sleep, Psychiatric Disorders, and the Transdiagnostic Perspective

health treatment. Of 103,788 operation en¬

dream-related indicators in individuals at

during freedom veterans seen at VA health

risk for suicide, he or she could potentially

care facilities, 25,658 (25%) received

identify early warning signs of new ide¬

psychiatric diagnoses, including PTSD;

ation around suicide and could therefore

56 percent of whom had two or more dis¬

act to prevent a new suicide attempt. In¬

tinct mental health diagnoses. Overall,

dividuals who have served their country in

31 percent received mental health and/or

combat deserve to have their sleep prob¬

psychosocial diagnoses. In a later study,

lems seriously and conscientiously ad¬

Seal et al. (2007) found that among 750

dressed by the health care system whose

Iraq and Afghanistan veterans who were

mission it is to serve veterans.

referred to a VA medical center and five associated community clinics, 338 under¬ went postdeployment screening with 233

Patrick McNamara

See also: entries related to PTSD and Dreams/ Sleep

(69%) screening positive for mental health problems. New treatment approaches are desper¬ ately needed to meet the mental health needs of the veteran population. Studies of sleep contributions to PTSD symptoms hold promise for developing better diag¬ nostic techniques for PTSD and for devel¬ oping innovative treatment approaches to PTSD and other mental health disorders of returning vets. Identifying specific effects of sleep disturbance on PTSD symptoms in the home environment should be con¬ sidered as well since nightmares are more likely to occur in the home environment than in the sleep lab. Investigators should

References Department of Veterans Affairs (DVA). (2005) Report no. 05-00765-137. Washington, DC: VA Office of Inspector General. Seal, K. H., Bertenthal, D., Maguen, S., Gima, K., Chu, A., & Marmar, C.R. (2008). Ad¬ ministration postdeployment mental health screening of veterans returning from Iraq and Afghanistan. American Journal of Pub¬ lic Health, 705(4), 40-47. Seal, K. H., Bertenthal, D., Miner, C.R., Sen, S., & Marmar, C.R. (2007). Bringing the war back home: Mental health disorders among 103,788 US veterans returning from Iraq and Afghanistan seen at Department of Veterans Affair facilities. Archives of Inter¬ nal Medicine, 767(5), 476-482.

seek to clarify the role of sleep dysregulation in production of PTSD symptomology and thus allow for better and more targeted therapeutic interventions for PTSD. REM sleep-related measures such as REM-sleep

Sleep, Psychiatric Disorders, and the Transdiagnostic Perspective

density and REM-sleep dreams and night¬ mares are significant predictors of sui¬

It is unequivocally the case that sleep dis¬

cidal ideation in patients with trauma and

turbance commonly co-occurs with psy¬

in depressed individuals. Some individu¬

chiatric disorders. Insomnia, the most

als with sleep problems and with PTSD

common sleep disturbance, is an ongo¬

are at greater risk for suicidal ideation. If

ing difficulty initiating sleep, maintaining

a clinician monitored such REM sleep and

sleep, waking up too early, or experiencing

Sleep, Psychiatric Disorders, and the Transdiagnostic Perspective


chronically nonrestorative sleep. Insomnia

day interferes with nighttime sleep, which

is listed as a symptom in the current def¬

in turn contributes to mood regulation dif¬

inition of many psychiatric disorders and

ficulty and symptoms on the subsequent

there are many other disorders where in¬

day (Harvey, 2008).

somnia is not listed as a formal symptom but insomnia is a known common feature. The goal of this article is to address two

Is Insomnia Transdiagnostic?

questions that arise from recognizing the

There has been a resurgence of inter¬

comorbidity between insomnia and psy¬

est in explicitly identifying and studying

chiatric disorders: (1) is insomnia an epi-

the common, or transdiagnostic, processes

phenomenon or a mechanism and (2) is

across psychiatric disorders. This is in

insomnia transdiagnostic?

contrast to the disorder focused approach often taken in which classification systems

Is Insomnia an Epiphenomenon or a Mechanism?

and research programs tend to specialize

A widely held assumption is that insom¬

tenance, and treatment. We propose that

nia is secondary to, or an epiphenomenon

consideration be given to insomnia as a

of, the so-called primary psychiatric disor¬

transdiagnostic process on the basis of (1)

der. However, evidence has accumulated

the high rates of co-occurrence between in¬

to indicate that insomnia is not an epiphe¬

somnia and psychiatric disorders, (2) the

nomenon, but is often a key mechanism

evidence across a range of disorders that

contributing to the multi factorial causa¬

the insomnia is not an epiphenomenon but

tion of psychiatric disorders. Specifically,

contributes to onset, relapse, and mainte¬

insomnia is a risk factor for, and can con¬

nance, and (3) the transdiagnostic applica¬

tribute to, the development and/or main¬

bility of the bidirectional sleep and mood

tenance of psychiatric disorders. Second,


in one disorder, seeking to systematically illuminate that one disorder’s cause, main¬

there is substantial evidence that insom¬

The advantages of explicitly recogniz¬

nia impairs quality of life and incurs great

ing insomnia as a transdiagnostic process

personal costs due to economic and social

are threefold. First, the results of the Na¬

disability. Third, evidence from the sleep-

tional Comorbidity Survey make a strong

deprivation literature indicates that one of

case for the relative rarity of pure cases.

the strongest adverse effects of sleep de¬

The majority of the lifetime disorders

privation is increased negative mood. Fi¬

are comorbid disorders. A transdiagnos¬

nally, studies have shown adverse effects

tic perspective argues that perhaps disor¬

of sleep deprivation on cognitive function¬

ders co-occur because they share common

ing, which may impair problem-solving


ability. Moreover, it seems likely that there

if some psychiatric disorders are similar

is a bidirectional sleep and mood relation¬

with respect to the processes that maintain

ship whereby an escalating cycle of distur¬

them, then advances made in the context of

bance in mood and symptoms during the

one disorder will be more rapidly tested for







Sleep Quality: A Behavioral Genetic Perspective

their application to other disorders. Third,


a transdiagnostic approach might lead to

Harvey, A.G. (2008). Insomnia, psychiatric disorders, and the transdiagnostic perspec¬ tive. Current Directions in Psychological Science, 17, 299-303.

the specification of a single treatment or treatment components that are effective across a wide range of disorders (Harvey, 2008).

Treatment Implications Is it possible to develop one transdiag¬

Manber, R., Edinger, J., Gress J., San PeddroSalcedo, M., Kuo, T., & Kalista, T. (2008). Cognitive behavioral therapy for insomnia enhances depression outcome in patients with comorbid major depressive disorder and insomnia. Sleep, 31, 489^-95.

nostic treatment protocol that effectively treats insomnia in all psychiatric disor¬ ders? This is important, as developing and disseminating transdiagnostic treat¬

Sleep Quality: A Behavioral Genetic Perspective

ment protocols would have massive pub¬ lic health implications by reducing the heavy burden on clinicians, who must al¬ ready learn multiple treatment protocols that often share many common theoreti¬ cal underpinnings and interventions. Also, given the association between poor sleep and impaired quality of life, it is possible that improving sleep improves the func¬ tioning of individuals with a range of psychiatric disorders. Finally, if insomnia and the symptoms/processes of psychi¬

Sleep quality refers to a collection of mea¬ surements of sleep including sleep latency (the time in minutes taken to get to sleep), sleep duration, sleep efficiency (time in bed divided by total sleep time), number of disturbances from sleep such as awak¬ enings due to bad dreams or poor com¬ fort, and the daytime effects of a poor night’s sleep, among others. Subjective sleep quality is often assessed by selfreport questionnaires and has widely been

atric disorders are mutually maintaining,

assessed by the Pittsburgh Sleep Quality

then does a transdiagnostic treatment also

Index (PSQI: Buysse, Reynolds, Monk,

reduce symptoms and processes associ¬

Berman, & Kupfer, 1989). The PSQI taps

ated with the comorbid psychiatric dis¬

into seven components of sleep that can be

order? One landmark study suggests the

combined to yield an overall measure of

answer to the latter question is a resound¬

sleep quality. Sleep quality varies between

ing yes! Depression outcomes were sub¬

individuals and this variation is accounted

stantially improved by administering the

for by a combination of genetic and envi¬

frontline treatment for insomnia, namely

ronmental influences. Behavioral genetic

cognitive-behavioral therapy for insomnia

studies using twins'provide a useful tool

(Manber et al., 2008).

for assessing the relative contribution of

Jennifer C. Kanady and

genes and environments to any trait under

Allison G. Harvey

study. By comparing the similarity within monozygotic twins (who share

See also: entries related to Sleep Disorders


of their genes) to the similarity within

Sleep Quality: A Behavioral Genetic Perspective


dizygotic twins (who share on average

that sleep patterns are significantly under

50% of their segregating genes) on a trait,

genetic control, and that regularity in sleep

twin studies allow us to determine the rel¬

stages may be important for good sleep

ative contribution of additive genetic (the


extent to which genes add up to influence

Recent work has aimed to further under¬

behavior), shared environmental (envi¬

stand the individual components of sleep

ronments that act to make twins within a

quality. Barclay and colleagues (2010)

pair similar), and nonshared environmen¬

examined the extent to which genes and

tal (environments that contribute to twin

environments account for the individual

dissimilarity) influences on a trait. Using

components of sleep quality, the pheno¬

this technique, genetic influences have

typic associations between them, and the

been found to account for around 33 to

overlap in the genetic and environmental

44 percent of the variance in subjective

influences accounting for the associations.

sleep quality (Heath, Kendler, Eaves, &

Genetic influences accounted for between

Martin, 1990; Partinen, Kaprio, Kosken-

30 and 47 percent of variance in the indi¬

vuo, Putoken, & Langinvainio, 1983).

vidual components, although there was no

These heritability estimates can be di¬

evidence for genetic effects on sleep dura¬

rectly compared to those of other phe¬

tion. It is likely that since sleep length is

notypes such as IQ—the heritability of

largely under voluntary control, environ¬

which has been estimated to be between

mental influences contribute a greater ex¬

50 and 90 percent. The remaining source

tent. Consequently the effect of genes is

of variance in sleep quality is largely ac¬

attenuated by social pressures to stay out

counted for by the nonshared environ¬

late at night coupled with the need to arise

ment. Such environmental influences may

early in the morning—thus reducing one’s

include negative life events, family con¬

sleep length. The individual components

flict, relationship issues, ill health, or un¬

of sleep quality were largely correlated,

employment—all of which are known to

which demonstrates that each of these as¬

be associated with poor sleep quality.

pects of sleep contribute to an underlying

Objective measures of sleep quality can

construct. Furthermore, genetic overlap

also be obtained using polysomnography.

between the components was substantial,

The latency, duration, and nightly patterns

which suggests that similar genes may be

of the four sleep stages, as well as rapid

responsible for different aspects of sleep

eye movement sleep (REM), may give an

quality. Behavioral genetic studies assess¬

indication of sleep quality. Using a twin

ing the genetic overlap between traits may

design, Linkowski (1999) observed that

help to guide molecular genetics. Knowl¬

genetic influences accounted for around

edge of the genes influencing one aspect

50 percent of the variation in Stages 2, 4,

of sleep may be useful for identifying

and delta sleep, although evidence for ge¬

genes associated with correlated symp¬

netic effects on REM sleep was inconclu¬

toms. Future studies aimed at identifying

sive. While this does not directly inform

specific gene variants implicated in differ¬

us about quality of sleep, it demonstrates

ent aspects of sleep are necessary to further




Sleep-Related Hallucinations and Ghost Tales

understand the complex processes under¬

into the Taxi” in Japan (Furuya et al., 2009;

lying sleep quality.

Kon-no, 1975). Recently, we suggested the Nicola L. Barclay

See also: entries related to Genetics of Sleep

possibility that the vivid visual hallucina¬ tions seen in progressive posterior cortical atrophy (PCA) share a similar mechanism


with some of the ghost tales experienced

Barclay, N.L., Eley, T.C., Buysse, D.J., Rijsdijk, F. V., & Gregory, A.M. (2010). Ge¬ netic and environmental influences on different components of the “Pittsburgh Sleep Quality Index” and their overlap. Sleep, 33, 659-668.

by normal people (Furuya, Ikezoe, Ohyagi,

Buysse, D.J., Reynolds, C.F., Monk, T. H., Berman, S.R., & Kupfer, D.J. (1989). The Pittsburgh Sleep Quality Index: A new in¬ strument for psychiatric practice and re¬ search. Psychiatry Research, 28, 192-213. Heath, A. C., Kendler, K. S., Eaves, E.J., & Martin, N.G. (1990). Evidence for genetic influences on sleep disturbance and sleep pattern in twins. Sleep, 13, 318-335. Linkowski, O. (1999). EEG sleep patterns in twins. Journal of Sleep Research, 8, 11-13. Partinen, M., Kaprio, J., Koskenvuo, M., Putoken, P., & Langinvainio, H. (1983). Genetic and environmental determination of human sleep. Sleep, 6, 179-185.

Miyoshi, & Fujii, 2006). Furthermore, re¬ ports of REM sleep behavior disorder or somnambulism



are becoming

more common


2007). Based on several review papers (Fuyuya et al., 2006; Stores, 2007), we developed diagnostic criteria consisting of central and core features to classify the ghost tales as far as possible into the four types described in Table 8.

Classification of Four Types of Hallucination Hypnagogic Hallucination-Like Ghost Tales (HyH) This type of hallucination is in principle the hypnagogic hallucination that occurs

Sleep-Related Hallucinations and Ghost Tales Though there are many ghost stories in various cultures around the world, the pathogenesis of a few types remains to be figured out. One is the hypnagogic hallu¬ cination, usually observed in narcolepsy,

in narcolepsy patients. The ghost image is not vivid but often rather vague, and it is sometimes accompanied by a cenesthopathy such as an incubus/succubus, a sense of being touched. The ghost sometimes speaks, makes a noise, or shakes the bed or room, and on rare occasions, converses with the sleeper.

when experienced by normal people with¬ out other diagnostic criteria. The other is

Highway Hypnosis-Like Ghost

highway hypnosis, in which fear is a com¬

Tales (HHy)

ponent. Highway hypnosis is illustrated by

Highway hypnosis (white-line fever or the

tales such as “The Vanishing Hitchhiker”

vanishing hitchhiker) has been defined as a

in the United States and “The Ghost Getting

tendency to become drowsy and suddenly

Sleep-Related Hallucinations and Ghost Tales


Table 8: Major Criteria for Classification of Ghost Tales of Normal People. (Three core features are sufficient for a definite diagnosis, two for a probable diagnosis, and one for a possible diagnosis.) 1. Hypnagogic hallucination-like ghost tales (HyH) Central features (essential for a diagnosis of HyH): HyH appears while the experiencer is sleeping or when they are waking from sleep. Core features: a. The image of the ghost is clear or vague but not very vivid. b. It sometimes accompanied by cenesthopathy such as an incubus/succubus, a feeling of being touched or a feeling of breathed on. c. The ghost sometimes speaks, makes a noise, or converses with the experiencer. Differential diagnosis: narcolepsy, schizophrenia 2. Highway hypnosis-like ghost tales (HHy) Central features (essential for a diagnosis of HHy): HHy is a tendency to become drowsy and suddenly fall asleep, sometimes into the REM stage, when driving an automobile. In HHy, the conscious and subconscious minds appear to concentrate on different things. Thus, this hallucination appears while the experiencer does not recognize the change of consciousness level. Core features: a. The sleep- or trance-like state can occur with the driver (experiencer) sitting in an upright position and staring ahead. b. The image of ghost is usually clear but sometimes vague. c. The ghost sometimes speaks or has a conversation with the experiencer. Differential diagnosis: complex partial seizure, temporal lobe epilepsy 3. REM sleep behavior disorder or somnambulism-like ghost tales (RBDS) Central features (essential for a diagnosis of RBDS): In REM sleep behavior disorder, the loss of motor inhibition leads to a wide spectrum of behaviors during sleep. In the case of somnambulism, it is usually defined by or involves the person performing normal actions as if awake. Thus, RBDS is closely related to sleep. Core features : a. The experiencer of RBD often has a dream at the same time, which convinces him/her that the events were real. b. The experiencer notices an abnormality in the bedroom or the experiencer himself or a bed partner after awakening, when the RBD is accompanied by somnambulism. c. The image of ghost is not as clear as it is in HHy because it is a part of dream. Differential diagnosis: early stage of dementia with Lewy bodies (DLB, parkinsonism), drug abuse (including alcoholism), malingering disorder 4. Vivid hallucination-like ghost tales (VH) Central features (essential for a diagnosis of VH): VH is similar to the hallucination occurred in a patient with DLB or Charles-Bonnet syndrome (CBD). The ghost appears without any relation to sleep.





Sleep-Related Hallucinations and Ghost Tales

Table 8: Major Criteria for Classification of Ghost Tales of Normal People. (Three core features are sufficient for a definite diagnosis, two for a probable diagnosis, and one for a possible diagnosis.) (Continued) Core features: a. The image of the ghost is clear or vivid. b. Hallucinations are purely visual (i.e., the ghost never talks or tries to touch the experiencer.) c. The ghost vanishes into air when the experiencer tries to touch it or throw something at the ghost. Differential diagnosis: early stage DLB (parkinsonism), CBD, drug abuser (including alcoholism), schizophrenia

fall asleep, sometimes into the REM stage,

like a ghost or monstrous creature has en¬

while driving an automobile (Furuya et al.,

tered in the bedroom and done something.

2009). Theoretically, highway hypnosis is

Thus, RBDS is closely related to sleep.

a kind of mental state that also occurs when a person concentrates on a simple mechan¬ ical task, so it may happen relatively fre¬ quently and in common situations; for example, workers performing simple re¬ petitive tasks while deprived of sleep and walkers concentrating on the road at night using the faint light of a lantern may expe¬ rience highway hypnosis. Thus, this type of hallucination seems to be unrelated to sleep at first, and the hallucinator does not

Vivid Hallucination-Like Ghost Tales (VH) Vivid hallucination is similar to the hal¬ lucinations that occur in patients with de¬ mentia with Lewy bodies, some types of PCA, and Charles-Bonnet syndrome (Fu¬ ruya et al., 2006; Stores, 2007). The ghost appears without any relationship to sleep at first and is a purely visual hallucination.

recognize the change in his or her con¬ sciousness level. The image of the ghost is usually clear but sometimes vague.

Classification and Analysis of Ghost Tales

REM Sleep Behavior Disorder or Somnambulism-Like Ghost Tales (RBDS)

We analyzed 183 reliable ghost tales col¬

In REM sleep behavior disorder, the loss of

to 1970 (Kon-no, 1975; Yanagita, 2006)

motor inhibition leads to a wide spectrum

and found that 66.1 percent of the tales

of behaviors during sleep. Somnambulism

of ghosts could be classified into the four

is usually defined by or involves the per¬

types listed (see Table 8) (Furuya et al.,

son performing normal actions as if awake

2009); 32.2 percent were sleep related

(walking, opening/closing a door or win¬

(HyH and RBDS), and 35.0 percent were

dow, and other acts) (Stores, 2007). The

not sleep related (HHy and VH) (Furuya et al., 2009).

sleeper thinks that someone or something

lected by Japanese folklorists from 1900

Sleep-Related Mental Activities in Insomnia: Role and Assessment


Conclusion We propose the possibility that almost two thirds of ghost tales may be classified into one of four types of hallucinations expe¬ rienced by normal people, which means that most of them are attributable to the same mechanisms as neurophysiological and neurodegenerative or psychological disorders. Akihiro Watanabe and Hirokazu Furuya See also: entries related to Sleep Disorders References Furuya, H., Ikezoe, K., Ohyagi, Y., Miyoshi, T., & Fujii, N. (2006). A case of progressive posterior cortical atrophy (PCA) with vivid hallucination: Are some ghost tales vivid hallucinations in normal people? Journal of Neurology, Neurosurgery, and Psychiatry, 77, 424-425. Furuya, H., Ikezoe, K., Shigeto, H., et al. (2009). Sleep- and non-sleep-related hal¬ lucinations—Relationship to ghost tales and their classifications. Dreaming, 19, 232-238. Kon-no, E. (1975). Nihon Kaidan Syu [Ghosts tales in Japan] (1st ed.). Tokyo, Japan: Syakaishisou-sya (in Japanese). Stores, G. (2007). Clinical diagnosis and misdi¬ agnosis of sleep disorders. Journal of Neu¬ rology, Neurosurgery, and Psychiatry, 78, 1293-1297. Yanagita, K. (2006). Toh-no Monogatari [The “Toh-no” Folktales] (8th ed.). Tokyo, Japan: Kadokawa-Shoten (in Japanese). Ghost of Oyuki (artist unknown, but presented as a work of Maruyama Ckyo, 1733-1795; Japa¬ nese artist) (Hanging scroll picture: ink and colors on paper). Note the vague image of the lower part of the body, corresponding to the hypnagogic hallucination-like ghost (HyH; Table). (Extended loan to the University of California, Berkeley Art Museum from a private collection)

Sleep-Related Mental Activities in Insomnia: Role and Assessment Insomnia is a widespread complaint af¬ fecting about 10 percent of the general




Sleep-Related Mental Activities in Insomnia: Role and Assessment

population on a chronic basis. Insomnia

A growing number of researchers and

is commonly explained by a hyperarousal

clinicians are recognizing the potential

state, present at bedtime, which could be

role of sleep-disruptive cognitions in in¬

cognitive as well as physiological, that

somnia and are thus incorporating cogni¬

interferes with normal sleep. Frequently,

tive therapy as a therapeutic component of

sleep habits and mental activities are

psychological interventions for insomnia.

modified following a night where insom¬

Some clinical trials have shown that these

nia is experienced to try to cope with the

therapeutic targets, including faulty be¬

situation. Therefore, as time passes, sleep

liefs and attitudes about sleep, are respon¬

habits, environment (such as a bedroom

sive to treatment and may actually play

or bedtime), and even mental activities

an important mediating role in reducing

become, by association, stimuli related to

insomnia symptoms and in maintaining

sleep disturbance and produce an insom¬

sleep improvements over time (Edinger,

nia state via a learning process (Morin,

Wohlgemuth, Radtke, Marsh, & Quillian,


Sleep-related mental activities

2001). To be able to assess these thoughts

such as faulty beliefs, worry, attribution,

and beliefs related to insomnia, specific

attentional bias, sleep perception, and

inventories or questionnaires are needed.

expectation play an important mediat¬

Such inventories will help in evaluating

ing role in perpetuating and exacerbating

patients’ responses to insomnia treatment,

insomnia (Harvey, Tang, & Browning,

which is of great clinical value. One of the

2005; Morin, 1993). To date, it is ac¬

first questionnaires related to thoughts in

knowledged that mental activities might

the context of insomnia was developed in

contribute to cognitive arousal at bedtime

1993 and is called Dysfunctional Beliefs

(Harvey et al., 2005). For instance, some

and Attitudes about Sleep questionnaire

insomnia sufferers tend to have unrealis¬

(Morin, 1993). It comprises 36 items eval¬

tic expectations about their sleep require¬

uating five dimensions of beliefs. Later,

ments and worry excessively when such

several shorter versions of this question¬

requirements are not met. Others fear

naire were developed, the most recent

the potential consequences of insomnia

being the DBAS-16 (Morin, Vallieres, &

on their daytime functioning and tend

Ivers, 2007). The DBAS-30 is also trans¬

to selectively channel their attention to¬

lated into several languages and is widely

ward any evidence of such consequences.

used around the world. This question¬

Some also evaluate quality of their sleep

naire, which possesses adequate psycho¬

upon awakening in the morning and will

metric properties, is an essential tool in

modify their daily functioning according

evaluating beliefs and thoughts pertaining

to their first sleep perception. However,

to insomnia. Other questionnaires target¬

such faulty expectations, perceptions,

ing cognitive process at bedtime or cogni¬

and excessive worry are producing emo¬

tive arousal have also been developed. To

tional distress and heightening arousal,

name only a couple there are the presleep

and will in turn feed the vicious cycle of

arousal scale (Nicassio, Mendlowitz, Fus¬


sed, & Petras, 1985) and Glasgow Content

Sleep Spindles

of Thoughts Inventory (Harvey & Espie, 2004). In summary, the role mental activities play in insomnia is well acknowledged al¬


Nicassio, P.M., Mendlowitz, D. R., Fussell, J. J., & Petras, L. (1985). The phenomenol¬ ogy of the pre-sleep state: The development of the pre-sleep arousal scale. Behaviour Research and Therapy, 23, 263-271.

though not yet clearly understood and dem¬ onstrated. Sleep-related mental activities include cognitions such as sleep percep¬

Sleep Spindles

tion, attentional bias, worry, and specific faulty beliefs about sleep. Moreover, given

Sleep stages are defined according to arbi¬

the importance attributed to cognitive pro¬

trary criteria based on the occurrence and

cess, it would be warranted to evaluate the

amount of specific phasic activities. Dur¬

unique contribution of cognitive interven¬

ing NREM sleep, brain activity is orga¬

tion alone to insomnia as it has not yet been

nized by spontaneous coalescent cerebral

assessed. Finally, a theoretical model that

rhythms: spindles, delta, and slow oscilla¬

includes the full range of potentially in¬

tions. On EEG recordings, spindles appear

volved cognitive processes is warranted to

as waxing-and-waning oscillations at a fre¬

provide a global view of mental activities

quency of about 11 to 15 Hz and a duration

in insomnia.

of more than 500 milliseconds. Spindles Annie Vallieres

are prominent during N2 sleep and are pro¬ gressively replaced during deeper stages

See also: entries related to Sleep Disorders

by low-frequency high-amplitude (slow


and delta) waves. Besides, spindles are

Edinger, J.D., Wohlgemuth, W. K., Radtke, R.A., Marsh, G. R., & Quillian, R.E. (2001). Does cognitive-behavioral insom¬ nia therapy alter dysfunctional beliefs about sleep? Sleep, 24, 591-599.

grouped by the slow oscillation. Spindles

Harvey, A. G., Tang, N.K., & Browning, L. (2005). Cognitive approaches to insomnia. Clinical Psychology Review, 25, 593-611.

The thalamus is a central structure for the

Harvey, K.J., & Espie, C.A. (2004). Devel¬ opment and preliminary validation of the Glasgow Content of Thoughts Inventory (GCTI): A new measure for the assessment of pre-sleep cognitive activity. British Jour¬ nal of Clinical Psychology, 43, 409-420. Morin, C.M. (1993). Insomnia: Psychological assessment and management. New York: The Guilford Press. Morin, C. M., Vallieres, A., & Ivers, H. (2007). Dysfunctional beliefs and attitudes about sleep (DBAS): Validation of a brief version (DBAS-16). Sleep, 30, 1547-1554.

are suppressed during surface negative half-waves of the slow oscillation (down state), but increased during positive half¬ waves (up state). generation of spindles. Within the thala¬ mus, pacemakers of spindle oscillations are located in thalamic reticular neurons. This assumption is supported by the finding that spindles are preserved within the reticular thalamus disconnected from the remaining thalamus and cerebral cortex. Although spindles can be generated within the thala¬ mus in the absence of the cerebral cortex, the neocortex is essential for the induction, synchronization, and termination of spin¬ dles. In the intact brain, spindles are pro¬ duced through thalamo-cortico-thalamic




Sleep Spindles

loops (cf. Steriade & McCarley, 2005). In

in rats, hippocampal ripples were found

humans, EEG recordings have character¬

to occur in temporal proximity to corti¬

ized spindle oscillations in terms of scalp

cal sleep spindles, indicating an informa¬

topography. Although they are detectable

tion transfer between the hippocampus and

on all EEG scalp derivations, spindles are

neocortex (Siapas & Wilson, 1998). This

most prominent over centro-parietal areas

neuronal replay in turn has been suggested

with a frequency above 13 Hz (De Genn-

as the basis for reorganization and consoli¬

aro & Ferrara, 2003). A second cluster of

dation of memories (Buzsaki, 1996; Steri¬

spindles is visible over frontal areas, with

ade, 1999). Gais and colleagues were then

a frequency of about 12 Hz. From this

the first to demonstrate that sleep spindle

topographical segregation the hypothesis

density is also related to declarative learn¬

emerged that two types of spindles are pro¬

ing in humans (Gais, Molle, Helms, &

duced by distinct biological mechanisms.

Bom, 2002). Interestingly, it has also been

In addition this is in line with the finding

postulated that an individual’s learning

that both spindle subtypes are differentially

potential might be well reflected in sleep

modulated by age, circadian and homeo¬

spindle activity (cf. Schabus et al., 2006).

static factors, menstrual cycle, pregnancy,

Manuel Schabus

and drugs (De Gennaro & Ferrara, 2003). EEG/fMRI studies of human sleep also support the existence of two spindle types (Schabus et al., 2007). In particu¬ lar these data revealed that—besides in¬ creased brain responses in the lateral and

posterior aspects of the thalamus, as well as in paralimbic (anterior cingulate cor¬ tex, insula) and neocortical areas—the fast spindle type is associated with increased hemodynamic activity in hippocampal and sensorimotor regions. This finding also in¬ dicated a possible differential functional significance of these two spindle types, with the fast spindle being more closely as¬ sociated with cognitive functioning (e.g., Morin et al., 2008). Yet more research is needed to unravel the functional signifi¬ cance of these two spindle types. In general spindles are of interest for cognition research as they have been di¬ rectly related to the repeated activation of thalamo-cortical or hippocampo-cortical networks after learning. Specifically,

See also: entries related to Sleep Assessment References Buzsaki, G. (1996). The hippocampo-neocortical dialogue. Cerebral Cortex, 6(2), 81-92. De Gennaro, L., & Ferrara, M. (2003). Sleep spindles: An overview. Sleep Medicine Re¬ views, 7(5), 423-440. Gais, S., Molle, M., Helms, K., & Born, J. (2002). Learning-dependent increases in sleep spindle density. Journal of Neurosci¬ ence, 22(15), 6830-6834. Morin, A., Doyon, J., Dostie, V., Barakat, M., Hadj Tahar, A., Korman, M., et al. (2008). Motor sequence learning increases sleep spindles and fast frequencies in post¬ training sleep. Sleep, 31(8), 1149-1156. Schabus, M., Dang-Vu, T.T., Albouy, G., Balteau, E., Boly, M., Carrier, J., et al. (2007). Hemodynamic cerebral correlates of sleep spindles during human non-rapid eye movement sleep. Proceedings of the National Academy of Sciences USA, 104 (32), 13164-13169. Schabus, M., Hodlmoser, K., Gruber, G., Sauter, C., Anderer, P., Klosch, G., et al. (2006).

Sleep Talking

Sleep spindle-related activity in the human EEG and its relation to general cognitive and learning abilities. European Journal of Neuroscience, 23(1), 1738-1746. Siapas, A.G., & Wilson, M. A. (1998). Coor¬ dinated interactions between hippocampal ripples and cortical spindles during slowwave sleep. Neuron, 21(5), 1123-1128. Steriade, M. (1999). Coherent oscillations and short-term plasticity in corticothalamic net¬ works. Trends in Neurosciences, 22(8), 337-345. Steriade, M. & McCarley, R. W. (2005). Brain control of wakefidness and sleep. New York: Springer.


There are three patterns in occurrence. The first and largest subgroup (about two thirds of childhood sleep talkers) is formed by real childhood sleep talkers; that is, those who do so as adults quite rarely or not at all. In the second subgroup are those that talked in their sleep frequently as children and continued to do so quite frequently as adults. These persons can be called persis¬ tent sleep talkers, and this subgroup forms about one fifth of those who talked in their sleep as children. The third and the small¬ est group (less than one tenth of adult sleep talkers) is formed by those adults who started to talk in their sleep as adults; that

Sleep Talking

is, adult-onset sleep talking (Hublin et al., 1998).

In sleep talking (somniloquy), the essen¬

Genetic effects play a role in sleep talk¬

tial feature is talking, with varying degrees

ing (Hublin & Kaprio, 2003). In a twin

of comprehensibility, during sleep (Inter¬

study, the proband-wise concordance rate

national Classification of Sleep Disorders

for childhood sleep talking was 0.53 in the

[ICSD-2], 2005). It can occur in both REM

monozygotic (MZ) pairs, and 0.36 in the

and non-REM sleep at any time during the

dizygotic (DZ) pairs. For adults, the pro-



band-wise concordance rate was 0.23 for

Shapiro, 1962). Sleep talking is highly

the MZ pairs and 0.14 for the DZ pairs. The

prevalent, occurring in childhood always

proportion of total phenotypic variance in

or often in 4 to 14 percent and now and

liability to sleep talking attributed to ge¬

then in 22 to 60 percent, and as adults in 1

netic influences in childhood sleep talking

to 5 percent and in 20 to 45 percent, respec¬

was 54 percent in males and 51 percent in

tively (Hublin & Kaprio, 2003). The true

females, and for adults it was 37 percent

prevalence is not easy to estimate because

among males and 48 percent among fe¬

subjects as a rule do not remember or are

males (Hublin et al., 1998).



not aware of their sleep talking. There is no

Traditionally sleep talking has been

clear gender difference in childhood sleep

classified as one of the parasomnias,

talking, but in adults it may be more com¬

which are undesirable physical events or

mon in males (Hublin, Kaprio, Partinen, &

experiences during the entry to sleep,

Koskenvuo, 1998). The occurrence of childhood and adult

within sleep, or during arousals from

sleep talking are highly correlated: about

tem activation (ICSD-2, 2005). Now it

80 percent of adults with sleep talking have

is considered more as a sleep-related

done so as a child (Hublin et al., 1998).

symptom that lies on the border between

sleep, reflecting central nervous





Sleep Variables and Handedness

normal and abnormal sleep. It is com¬ mon that parasomnias co-occur (Hublin, Kaprio, Partinen, & Koskenvuo, 2001). In childhood, the correlations were high¬ est in sleep talking for co-occurrence with sleepwalking (r = 0.73), nightmares (0.50), and bruxism (0.43). The results are similar in co-occurrence as adults,

Hublin, C., Kaprio, J., Partinen, M„ & Kosken¬ vuo, M. (1998). Sleeptalking in twins: Epi¬ demiology and psychiatric co-morbidity. Behavior Genetics, 28, 289-298. Hublin, C., Kaprio, J., Partinen, M., & Ko¬ skenvuo, M. (2001). Parasomnias: Co¬ occurrence and genetics. Psychiatric Genet¬ ics, 11, 65-70. International


of Sleep


although the correlations are somewhat

orders: Diagnostic and Coding Manual

lower (0.56, 0.43, and 0.39, respec¬

(ICSD-2) (2nd ed.). (2005). Chicago: Amer¬ ican Academy of Sleep Medicine.

tively). In MZ twins the co-occurrence of sleepwalking and sleep talking is clearly higher (0.31) compared to DZ twins (0.05).

Rechtschaffen, A., Goodenough, D. R., & Sha¬ piro, A. (1962). Patterns of sleeptalking. Ar¬ chives of General Psychiatry, 7, 418-426.

The correlations are substantial (>0.15 in MZ pairs) in three combinations: sleep talking-sleepwalking,



bruxism, and sleep talking-nightmares. Sleep talking is usually benign but

Sleep Variables and Handedness: Methodological Issues and State of the Field

chronic cases in adults may relate to psy¬ chopathology (Rechtschaffen et al., 1962).

There are several issues that make it dif¬

In adults, psychiatric comorbidity is about twice as common in those with frequent

ficult to determine if sleep variables might

sleep talking (highest in those with adult-

(handedness). Nevertheless, because indi¬

onset sleep talking, odds ratio 3.8), com¬

vidual variations in handedness may re¬

pared to those with infrequent or no sleep

flect individual variations in functional

talking, but most cases of sleep talking are

and structural brain organization, it is

not associated with serious psychopathol¬

worthwhile to examine the sleep of differ¬

ogy (Hublin et al., 1998).

ent handedness groups. Ultimately, such

vary as a function of hand use preference

In conclusion, sleep talking is common

investigations could help to shed light on

but little studied, reflecting the fact that it is

neurophysiological processes that occur

usually a harmless phenomenon. However, if it is frequent or loud it can be disturbing,

during sleep, as well as on the functions of sleep in general.

and sometimes the content can cause prob¬

One issue that makes it difficult to deter¬

lems in intimate relationships. Christer Hublin See also: entries related to Parasomnias

mine handedness-sleep relationships in¬ volves the very definition of handedness. Traditionally, handedness has been divided into left- versus right-handers, with perfor¬


mance on one (e.g., writing hand) or multi¬

Hublin, C., & Kaprio, J. (2003). Genetic as¬ pects and genetic epidemiology of parasom¬ nias. Sleep Medicine Reviews, 7, 413—421.

ple test items (e.g., drawing, using a knife, etc.) indicating handedness. Thus, the di¬ rection of hand preference—right versus

Sleep Variables and Handedness


left (regardless of whether one strongly

sleep length, while others focused on is¬

prefers to use one vs. the other hand)—

sues of sleep quality, such as insomnia-

is the important measure. However, other

related measures. Some work objectively

work suggests that how strongly one pre¬

recorded sleep, while some focused on

fers to use one hand (e.g., always one vs.

self-reported, subjective measures of sleep

the other hand, sometimes one vs. the

variables. Any attempt at synthesis of the

other, or no preference) across a variety of

literature must take this methodological

test items is also, or in some cases more,

variation into account; as will be seen,

important to investigate. Thus, in these

methodology can interact with both the



measure examined and with the handed¬

preference—consistent versus inconsistent

ness groups tested, resulting in complex

(e.g., regardless of direction; that is, regard¬

relationships between these variables.




less of left vs. right hand)—is the means

Given the methodological challenges

by which handedness is categorized. Still

outlined earlier, why would one bother to

other studies examine handedness by cat¬

suspect that individual differences in hand

egorizing across both degree and direction,

preference might indicate individual dif¬

comparing consistently left, consistently

ferences in sleep measures? First, NRH

right, and inconsistent-handers.

versus RH differ neuroanatomically. For

Unfortunately, investigations of hand¬

example, NRH compared to RH have a

edness-sleep relationships have not been

larger corpus callosum, that part of the brain

consistent in their division of the hand¬

responsible for connecting the two cerebral

edness groups; it is therefore difficult to

hemispheres (e.g., Denenberg, Kertesz, &

synthesize the body of literature into a co¬

Cowell, 1991; Witelson & Goldsmith,

herent whole. Given the inconsistent clas¬

1991). NRH also have decreased neuro-

sification of the handedness groups across

anatomical asymmetries; for example, in

studies, in the present article consistent-

language-related areas (e.g., Propper et ah,

left-handers and inconsistent-handers are

2010). In addition to differences in struc¬

collapsed into a non-right-handed (NRH)

tural organization, NRH versus RH differ

group that is compared to right-handers

in the functional organization of the brain,

(RH). It is hoped that what may be lost

with reversed or bilateral lateralization of

in lack of precision will be gained in

cerebral functions in NRH (Hellige, 1993).


For example, NRH is associated with in¬

A second issue that makes it difficult

creased incidence of right hemisphere or

to determine handedness-sleep relation¬

bilateral language processing (e.g., Knecht

ships involves the methodology used to

et al., 2000), as well as with atypical neu-

collect and define sleep variables. For ex¬

roanatomic asymmetries in language areas

ample, while some studies examined the

(e.g., Propper et al., 2010). To the extent

sleep of different handedness groups in a

sleep recruits the same neuroanatomi-

sleep laboratory, others examined equally

cal substrates that differ between NRH

important home sleep. Some studies fo¬

and RH, the handedness groups will dif¬

cused on sleep-quantity measures, such as

fer in their sleep. Comparisons between




Sleep Variables and Handedness

handedness groups can therefore inform

issue, several other investigations have re¬

us about the neuroanatomical structures

ported no handedness differences in sleep

involved in, and functional organization

quality (e.g., Porac & Searleman, 2006;

of the brain during, sleep.

Violani, De Gennaro, & Solano, 1988).

In fact, despite the infancy of the field,

Other measures of sleep also demon¬

there are demonstrated differences in sleep

strate handedness effects, although again,

variables between


these effects vary as a function of method¬

For example, sleep quality may differ as

ology. For example, self-reports indicate

a function of handedness, especially in

decreased sleep, and possibly decreased

studies examining self-report measures, or

sleep needs, in NRH compared to RH

that look at pathologies associated with

(Hicks, Pellegrini, & Hawkins, 1979; Prop¬



per, 2000). At least partly consistent with

greater symptoms of insomnia (Coren &

the self-report literature, Kilgore, Lipizzi,

Searlman, 1987; Hicks, DeHaro, Inman, &

Grugle, Killgore, and Balkin (2009) re¬

Hicks, 1999), including greater difficulty

ported increased sleep duration, and better

falling asleep, more middle-of-the-night

sleep, in RH compared to NRH, in a sleep

awakenings, and greater difficulty falling

laboratory, but not in at-home measures.

back to sleep, compared to RH. In labora¬

However, Lehnkering Strauss, Wegner,

tory examinations, NRH also suffer from

and Siegmund (2006) reported actigraph-

more severe sleep apnea compared to RH (Hoffstein, Chan, & Slutsky, 1993). The

measured sleep-duration differences be¬

NRH have a higher incidence of enuresis

having a longer sleep duration compared

(Ferrara et al., 2001) as well. However,

to RH. Finally, sleep diary (Violani et al.,

in the only studies explicitly attempting

1988) and home monitoring (Propper et al.,

to disentangle the contribution of direc¬

2004, 2007) showed no handedness differ¬

tion versus degree of hand preference to

ences in sleep length.


For example,


tween the handedness groups, with NRH

sleep using objective at-home sleep moni¬

Differences between handedness groups

toring, RH and left-handers, compared to


inconsistent-handers, demonstrated longer

sured by sleep-duration deviation from a

time to fall asleep and an increased amount

standard norm have also been reported,

of time spent awake during the night

although again the direction of this dif¬

(Propper, Christman, & Olejarz, 2007;

ference has been conflicting. Hicks and

Propper, Lawton, Przyborski, & Christ¬

colleagues (1979), using a questionnaire,

man, 2004), the opposite of what would

reported greater deviation from a standard

have been expected based on the self-report

norm in the inconsistent-handers versus

literature, suggesting an effect of methods

consistent-handers, while Violani and col¬

of sleep assessment on sleep variables,

leagues (1988), using a sleep diary, re¬

and the possibility that degree, rather than

ported the opposite. Propper and colleagues

direction, of hand preference may be an

(2004) found no handedness effects on this

important mediator of handedness-sleep

measure examining objectively recorded home sleep.

relationships. To further confound the





Sleep Variables and Handedness


Very few other studies have gone be¬

with NRH demonstrating no change in am¬

yond description of sleep duration or qual¬

plitude as a function of sleep time, and RH

ity as a function of handedness. Those that

demonstrating decreased amplitude during

have, have found a relationship between

the last four hours of sleep in both the left

handedness and sleep architecture, or be¬

and right hemisphere.

tween handedness and other physiological

There are several points to be taken from

components of sleep. For example, Prop-

the previously mentioned review. First, the

per et al. (2004, 2007) found differences

method of sleep monitoring is an impor¬

in sleep architecture among consistently

tant variable to consider in examinations

left-, consistently right-, and inconsis¬

of handedness-sleep relationships. For ex¬

tently handed individuals in objective

ample, self-report measures may not actu¬

home sleep. Left-handers spent the most

ally measure sleep, but rather some other

time (M = 76%) in nonrapid eye move¬

cognitive process involved in the percep¬

ment (NREM) sleep, inconsistent-handers

tion of sleep. The bulk of the literature in¬

spent the second most time (M = 72%) in

dicates that it is in the self-perception of

NREM, and RH the least amount of time

sleep in which the handedness groups dif¬

in NREM (M = 62%). The opposite pat¬

fer. Specifically, it is interesting to note

tern was obtained for rapid eye movement

that the perception of sleep quality and

(REM) sleep: left-handers spent the least

duration, measured via self-report, does

amount of time in REM (M = 20%), incon¬

vary as a function of hand preference, with

sistent-handers the second most amount of

NRH believing they need less, receive

time in REM (M - 24%), and right-handers

less, and have poorer, sleep. It is not clear,

the most (M = 31%). The number of dis¬

on the other hand, if objective measures

crete REM episodes, however, showed a

of sleep quality (other than examination

different story, with inconsistent-handers

of sleep-associated pathological condi¬

having the most REM episodes (M = 4.7),

tions) or sleep duration show differences

left-handers the second most (M= 3.8), and

between handedness groups. Second, al¬

right-handers the least (M = 3.2).


The handedness groups also differ in




are conflicting, and vary as a function of


methodology, laboratory measures clearly

Nielsen, Abel, Lorrain, and Montplaisir

indicate differences between the handed¬

(1990) reported increased electroenceph-

ness groups in sleep architecture and neu¬

alographic coherence in NRE1 versus RH

rophysiology. The results of these studies

during wake, Stage 2, and REM sleep.

suggest that during sleep, patterns of in-

Murri and colleagues (1984) found dif¬

terhemispheric communication vary as a

ferences between NRH and RH in REM-

function of hand preference. It is likely that

sleep EEG asymmetry as measured by

these individual differences in handedness

EEG power. Finally, Serafetinides (1991)

effects reflect the differences in brain or¬

reported differences in EEG amplitude as a

ganization between NRH and RH; specifi¬

function of both handedness and sleep time

cally, larger corpus callosum in the NRH

(first four hours vs. last four hours of sleep),

may result in increased interhemispheric






Sleep Variables and Handedness

communication during sleep. Such find¬ ings suggest that sleep itself involves alter¬ ations in interhemispheric communication, possibly as a function of sleep stage. Third, given the overall paucity of studies ex¬ amining sleep-handedness relationships, clearly more research is needed to disen¬ tangle the effects of the latter variable on the former. Ruth E. Propper See also: entries related to Sleep and the Brain

Knecht, S., Drager, B., Deppe, M., Bobe, F., Fohmann, H., Floel, A.R.,. . . Henningsen, H. (2000). Handedness and hemispheric language dominance in healthy humans. Brain, 123, 2512-2518. Fehnkering, H., Strauss, A., Wegner, B., & Siegmund, R. (2006). Actigraphic inves¬ tigations on the activity-rest behavior of right- and left-handed students. Interna¬ tional Chronobiology, 23, 593-605. Murri, F., Stefanini, A., Bonanni, E., Cei, G., Navona, C., & Denoth, F. (1984). Hemi¬ spheric EEG differences during REM sleep in dextrals and sinistrals. Research Com¬


munications in Psychology: Psychiatric Be¬

Coren, S., & Searleman, A. (1987). Left sid¬ edness and sleep difficulty: The Abnor¬ mal Syndrome. Brain and Cognition, 6, 184-192.

havior, 9, 109-120.

Denenberg, V. H., Kertesz, A., & Cowell, P. E. (1991). A factor analysis of the human’s corpus callosum. Brain Research, 548, 126-132. Ferrara, P., Ruggiero, A., Diocialuti, L., Paolini Paoletti, F., Chiozza, M.L., & Calone, P. (2001). Primary Nocturnal Enuresis and left-handedness. Scandinavian Journal of Urology and Nephrology, 35, 184-185. Hellige, J. B. (1993). Hemispheric asymmetry: What’s right and what’s left. Cambridge, MA: Harvard University Press. Hicks, R. A., DeHaro, D., Inman, G., & Hicks, G.J. (1999). Consistency of hand use and sleep problems. Perceptual and Motor Skills, 89, 49-56. Hicks, R.A., Pellegrini, R.J., & Hawkins, J. (1979). Handedness and sleep. Cortex, 15, 327-229. Hoffstein, V., Chan, C. K., & Slutsky, A.S. (1993). Handedness and sleep apnea. Chest, 103, 1860-1862. Kilgore, W.D., Lipizzi, E.L., Grugle, N.F., Killgore, D.B., & Balkin, T.J. (2009). Handedness correlates with actigraphically measured sleep in a controlled environment. Perceptual and Motor Skills, 109, 395-400.

Nielsen, T., Abel, A., Forrain, D., & Montplaisir, J. (1990). Interhemispheric EEG coherence during sleep and wakefulness in left-and right-handed subjects. Brain and Cognition, 14, 113-125. Porac, C., & Searleman, A. (2006). The rela¬ tionship between hand consistency, health, and accidents in a sample of adults over the age of 65 years. Laterality, 11, 405^-14. Propper, R.E. (2000, June). Perceived sleep needs and feelings of alertness: Handedness and familial sinistrality effects. Poster pre¬

sented at the American Psychological Soci¬ ety, Miami, Florida. Propper, R.E. (2004). Handedness differences in self-assessment of sleep quantity: Non¬ right versus strong-right-handers. Sleep and Biological Rhythms, 2, 99-101 Propper, R.E., Christman, S.D., & Olejarz, S. (2007). Home-recorded sleep architecture as a function of handedness II: Consistent right-versus consistent left-handers. Jour¬ nal of Nervous and Mental Disease, 195,

689-692. Propper, R.E., Lawton, N„ Przyborski, M., & Christman, S.D. (2004). An assessment of sleep architecture as a function of degree of handedness in college women using a home sleep monitor. Brain and Cognition, 54, 186-197.

Sleepiness and Driving


Propper, R.E., O’Donnell, L.E., Whalen, W., Tie, Y., Norton, I.H., Suarez, R.O., . . . & Golby, A.J. (2010). A combined fMRI and DTI examination of functional language lat¬ eralization and arcuate fasciculus structure: Effects of degree versus direction of hand preference. Brain and Cognition, 73, 85-92.

drugs that act on the central nervous system

Serafetinides, E. A. (1991). Cerebral domi¬ nance and sleep: A comparison according to handedness and time of sleep. Interna¬ tional Journal of Neuroscience, 61, 91-92.

sive sleepiness (Drake et al., 2010).

Violani, C., De Gennaro, L., & Solano, L. (1988). Hemispheric differentiation and dream recall: Subjective estimates of sleep and dreams in different handedness groups.

(CNS), and diseases that affect the CNS (Roehrs, Carskadon, Dement, & Roth, 2005). In the general population, insuffi¬ cient sleep due to reduced time in bed at night is the most common cause of exces¬ The proportion of accidents related to specific sleep disorders is not known. One study indicates an accident rate of 13 per million kilometers for those with a sleep disorder, compared to 0.8 for a control group (Horstmann et al., 2000). There is

International Journal of Neuroscience, 39,

evidence that those with obstructive sleep


apnoea hypopnea syndrome

Witelson, S.F., & Goldsmith, C.H. (1991). The relationship of hand preference to anatomy of the corpus callosum in men. Brain Re¬ search, 545, 175-182.


have up to seven times greater risk of crashes compared to those without OSA (Teran-Santos, Jimenez-Gomez, & Cordero-Guevara, 1999). The majority of sleep-related crashes are not in people with predisposing condi¬

Sleepiness and Driving

tions but in drivers, largely young males, who are sleep deprived and who fall asleep

Anecdotally, motor vehicle accidents due

while driving at night. There are clear ef¬

to sleepiness have been reported since

fects of time of day on motor vehicle acci¬

1929 (Kennedy, 1929). Epidemiological

dents, with peaks in the early morning and

studies indicate that sleep-related crashes

midafternoon (Akerstedt et al., 1994b; Lan¬

represent up to 20 percent of all traffic ac¬

glois et al., 1986). Research has shown that

cidents in industrial societies (Connor et

sleep restriction for 24 hours impairs driver

al., 2002). In the United States, Israel, Ger¬

performance to the same extent as alcohol

many, and Sweden, sleep-related vehicle

intoxication (Dawson & Reid, 1997).

accidents account for many accidents on

Estimates of the proportion of accidents

nonurban roads and cause greater driver

attributable to sleep vary widely: 1 to 3 per¬

mortality and morbidity than other types of

cent in the United States and 10 percent in

accidents because of the greater speed on

France. In the United Kingdom, approxi¬

impact (Akerstedt et al., 1994a; Langlois,

mately 300 people are killed on the roads

Smolensky, His, & Weir, 1986).

per year due to a driver falling asleep at the

Numerous studies have demonstrated

wheel. In the United States, an estimated

that the underlying causes of excessive

1,202 people were killed annually as a re¬

sleepiness include reduced or fragmented

sult of sleepiness, drowsiness, and fatigue

sleep, circadian variations in alertness,

driving in 2009.




Sleepiness and Driving

Many sleep-related vehicle accidents

than their employees, and can be crimi¬

occur while drivers are at work (Leger,

nally liable for breaching the legislation.

1988)—for example, driving company

Additionally, organizations may be pros¬

cars or lorries (Maycock, 1996). The De¬

ecuted under the Corporate Manslaughter

partment of Motor Transportation in the

and Corporate Homicide Act 2007 in the

United States now considers that there

event of a fatality due to a gross failing

is a high likelihood that every lorry will

in their management of health and safety.

be involved in at least one sleep-related

It is therefore important for employers to

crash during the lifetime of the vehicle

meet their legal duties to the public, while

(Knipling &Wang, 1994). Around 40 per¬

protecting the health and safety of its driv¬

cent of sleep-related crashes involve com¬

ers and ensuring the need to improve pub¬

mercial vehicles. This type of accident is

lic safety.

most frequent on highways/motorways






and similar roads. In the United Kingdom,

national database for road accidents, does

fatal road accidents involving lorries, per

not normally record causal factors. Even

100 million vehicle kilometers, is almost

when these (or contributory) factors are as¬

double that for cars (averaging 2.1 vs. 1.1

signed, they are often assigned incorrectly

over the past five years). A survey in the

(Horne & Reyner, 1999). For example, many

United Kingdom found that 29 percent of

sleep-related vehicle accidents, whether

4,600 respondents admitted to having felt

these involve cars, lorries, or other vehicles,

close to falling asleep at the wheel in the

are simply attributed to driver inattention.

previous year, and 17.9 percent had acci¬

This general situation regarding unreliable

dents during the previous three years. Of

national statistics on sleep-related vehicle

these, and for those accidents on motor¬

accidents is typical for most other Western

ways, 15 percent were sleep-related vehi¬

countries (Akerstedt et al., 1994a,b).

cle accidents (Knipling & Wang, 1994).

Another reason for drivers to deny hav¬

Most drivers causing sleep-related ve¬

ing fallen asleep may be that the driver

hicle accidents usually deny having fallen

genuinely had no recollection of actually

asleep. The evidence pointing to the ac¬

having fallen asleep. Sleep laboratory stud¬

cident being related to sleep has to come

ies show that people who fall asleep typi¬

from other sources. There are different pos¬

cally deny having been asleep if awoken

sible reasons for this denial—such as loss

within a minute or two (Bonnet & Moore,

of insurance indemnity and fear of prosecu¬

1982). It has been shown that two to four

tion. The law puts the responsibility on the

minutes of sleep had to elapse before >50

driver not to drive if sleepy. The U.K. Road

percent of people acknowledged that they

Traffic Act 1988 (as amended) states that

were asleep (Gastaut & Broughton, 1965).

a driver must not drive without due care

Drivers may be aware of precursory feel¬

and attention. Section 3(1) of the Health

ings of sleepiness, although they may not

and Safety at Work etc Act 1974 (HSW

acknowledge having fallen asleep and may

Act) makes clear that employers (and self-

not even remember this after the accident

employed people) have duties to those other

(Horne & Reyner, 1999).

Sleepiness and Driving


OSAHS is the best studied cause of

subsequent risk of a motor vehicle acci¬

sleepiness and its effects on driving perfor¬

dent is necessary, matched by an increase

mance. One study estimated that up to 15

in public awareness of the risks of driving

percent of lorry drivers may have sleep ap-

while sleepy.

noea and sleepiness (Howard et ah, 2004).

Sopna Choudhury, Ajit Thomas, Shahrad

In the United Kingdom, there are approx¬

Taheri, and Dev Banerjee

imately 500,000 drivers and that would equate to around 75,000 with OSAHS. U.K. Driver and Vehicle Licensing

See also: Primary Disorders of Hypersom¬ nolence and Dreams; entries related to Sleep Disorders

Agency (DVLA) guidelines recommend that, for group-2 LGV/PCV license hold¬ ers: For patients diagnosed with OSAHS “Driving must cease until satisfactory con¬ trol of symptoms has been attained with ongoing compliance with treatment, con¬ firmed by consultant/specialist opinion (i.e., can restart driving commercial vehi¬ cles). Regular, normally annual, licensing review [is] required.” This means that the DVLA does permit drivers with OSA to get back to driving once their symptoms

Note Both Dr. Shahrad Taheri and Dr. Sopna Choud¬ hury are funded by the National Institute for Health Research (NIHR) through the Collabo¬ rations for Leadership in Applied Health Re¬ search and Care for Birmingham and Black Country (CLAHRC-BBC) programme. The views expressed in this publication are not nec¬ essarily those of the NIHR, the Department of Health, NHS South Birmingham, University of Birmingham, or the CLAHRC-BBC Theme 8 Management/Steering Group.

are controlled. Across the United King¬ dom, this is commonly within 14 days of starting continuous positive airway pres¬ sure (CPAP) therapy (CPAP delivers air to the airways to keep them open). There¬ fore, commercial drivers should neither fear the necessary tests for OSAHS, nor that the DVLA will revoke their licenses, provided they are compliant with the effec¬ tive therapy (Banerjee, 2011). Sleep-related motor vehicle accidents can be reduced through a greater aware¬ ness by drivers and employers of the dan¬ ger of driving while sleepy, and that such driving behavior is unacceptable. The risk of motor vehicle accidents among people with OSA can be reduced by its clinical diagnosis and treatment with CPAP. More research into the aware¬ ness of sleepiness among drivers and the

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Sleeping and Dreaming Patterns in the Context of Attachment Relationships

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Office of Crash Avoidance Research, U.S. Department of Transportation.

are more likely to be classified as inse¬

Langlois, P. H., Smolensky, M. H., His, B. P., & Weir, F.W. (1986). Temporal patterns of reported single-vehicle car and truck ac¬ cidents in Texas USA during 1980-1983. Chronobiology International, 2, 131-146. Leger, D. (1988). The cost of sleep-related acci¬ dents: A report for the National Commission

curely attached, and insecure infants ex¬ perience more night awakenings and sleep disorders. McNamara (2004) proposed that REM sleep is a viable candidate for a physiological mechanism through which humans can consolidate and integrate at¬ tachment experiences. Recent research on

Sleeping and Dreaming Patterns in the Context of Attachment Relationships


adult attachment has shown that anxious attachment contributes to decreased Stages 3^1 sleep in depressed women (Troxel, Cyranowski, Hall, Frank, & Buysse, 2007) and poorer sleep quality in the elderly (Verdecias et ah, 2009). Anxious attachment is also associated with a-EEG anomalies (Sloan, Maunder, Hunter, & Moldofsky, 2007). Extending this work into the realm of dream research, McNamara, Andresen, Clark, Zborowski, and Duffy (2001) found that anxious-attached individuals recalled more dreams than their secure counter¬ parts. In addition, their dreams were longer and contained more high-intensity central

Secure base support for exploration. (Photo pro¬ vided by Dylan Selterman)

images. The authors proposed that dream¬ ing exists in part to promote relational strategies and processes, and therefore anxious-attached individuals would dream

Selterman and Drigotas (2009) exam¬

more frequently due to their hyperactivat¬

ined the dreams of individuals in com¬

ing attachment patterns.

mitted dating relationships. Anxious- and

Avihou (2006; unpublished dissertation)

avoidant-attachment scores both uniquely

documented associations between dream

predicted stress, conflict, and anxiety

content and attachment styles. Anxious-

levels in dreams that contained roman¬

attached individuals dreamt of themselves

tic partners. The effects were stronger for



avoidant attachment. Anxious attachment

avoidant-attached individuals dreamt of

also correlated with feelings of jealousy,

themselves as distant, uncooperative, emo¬

and avoidant attachment correlated with

tionally unexpressive, or angry. Mikulincer,

anger and less affection in dreams contain¬

Shaver, Sapir-Lavid, and Avihou-Kanza

ing romantic partners.



or unloved,

(2009) separately reported findings from

An important point to note is that

the same sample, coding a subset of distress

(nearly) all the effects listed earlier re¬

dreams using three attachment-specific be¬

mained significant when statistically con¬

havioral tendencies: (1) support seeking,

trolling for general, nonattachment distress

(2) support availability, and (3) distress re¬

(anxiety, depression), as well as other so¬

lief. Anxious-attachment scores correlated

cial/emotional/personality variables. This

negatively with support availability and

demonstrates the unique contribution of

distress relipf, while avoidant-attachment

attachment to sleeping and dreaming pro¬

scores correlated negatively with support

cesses over and above other psychologi¬

seeking and support availability.

cal variables. Another consistent trend in




Social Network Analysis of Dream Content

this literature is the strong association be¬ tween anxious attachment and sleep pat¬ terns, while avoidant attachment appears largely absent. However, effects between avoidant attachment and dream content are just as strong as effects for anxious at¬ tachment (if not more so). Future research should probe deeper into this discrep¬ ancy. Researchers should also examine how sleep and dream patterns impact re¬ lationship functioning and maintenance. Perhaps dream sharing/disclosure with at¬ tachment figures exists as a form of secure base support seeking, or as an intimacy¬ building activity.

Veredecias, N. R., Jean-Louis, G., Zizi, F., Casimir, G. J., & Browne, R. C. (2009). Attachment styles and sleep measures in a community-based sample of older adults. Sleep Medicine, 10, 664-667. Troxel, W.M., Cyranowski, J.M., Hall, M., Frank, E., & Buysse, D.J. (2007). Attach¬ ment anxiety, relationship context, and sleep in women with recurrent major depression. Psychosomatic Medicine, 69(1), 692-699. Zborowski, M.J., & McNamara, P. (1998). Attachment hypothesis of REM sleep: To¬ ward an integration of psychoanalysis, neu¬ roscience, and evolutionary psychology and the implications for psychopathology re¬ search. Psychoanalytic Psychology, 75(1), 115-140.

Dylan Selterman

References McNamara, P. (1996). REM sleep: A social bonding mechanism. New Ideas in Psychol¬ ogy, 74(1), 35^16. McNamara, P. (2004). An evolutionary psy¬ chology of sleep and dreams. Westport, CT: Praeger. McNamara, P., Andresen, J., Clark, J., Zborowski, M., & Duffy, C.A. (2001). Im¬ pact of attachment styles on dream recall and dream content: A test of the attachment hypothesis of REM sleep. Journal of Sleep Research, 70(2), 117-127. Mikulincer, M., Shaver, P. R., Sapir-Lavid, Y., & Avihou-Kanza, N. (2009). What’s inside the minds of securely and insecurely at¬ tached people? The secure-base script and its associations with attachment-style di¬ mensions. Journal of Personality and So¬ cial Psychology, 97(4), 615-633. Selterman, D., & Drigotas, S. (2009). Attach¬ ment styles and emotional content, stress, and conflict in dreams of romantic partners. Dreaming, 19(3), 135-151. Sloan, E.P., Maunder, R.G., Hunter, J.J., & Moldofsky, H. (2007). Insecure attachment is associated with the a-EEG anomaly during sleep. BioPsychoSocialMedicine, 7(20), 1-6.

Social Network Analysis of Dream Content In a social network, people are represented by points, and if two people have a cer¬ tain relationship, for example, are friends, their corresponding points are connected by a line. Although social networks have complex and individualistic structures, they tend to have some simple properties in common, such as short paths between points. In a dream social network, points represent characters in the dreams of an in¬ dividual and a line connecting two points indicates that the corresponding characters were in a dream together. A dream social network shows how the dreamer’s mem¬ ory for people is organized in the dream¬ ing brain. Social interactions are a large part of the contents of dreams. During rapid eye movement (REM) sleep, when most dreams occur, a component of the brain involved in processing social interactions, the amygdala, is more active than during

Social Network Analysis of Dream Content


waking life. More social interactions occur

Van de Castle, 1966). The system gives

during an interval of REM sleep than in

simple rules for determining when to code

an equal interval of waking life (McNa¬

a character of a dream. For example, the

mara, McLaren, Smith, Brown, & Stick-

first rule that leads to a character being

gold, 2005). In any one, dream characters

coded is “The character is described as

may seem to appear in a haphazard way,

being physically present in the dream.”

but over many dreams a systematic struc¬ ture emerges.

With the system, a character need not be present in the dream to be coded. For ex¬

The dream social network for Arlie,

ample, if a belonging of a person is pres¬

a middle-aged woman, is shown in the

ent in the dream, the person is coded as

dream social network image. An isolated

a character of the dream. The system was

point corresponds to a character in a dream

modified for the purpose of constructing

with no other character present except the

networks, so a character is coded as pres¬

dreamer. Islands of points connected to

ent in a dream if the character interacted, or

each other but not connected to the rest of

could have interacted, with another char¬

the network represent characters appear¬

acter or with the dreamer (Schweickert,

ing in a dream with each other, but not

2007). Characters include people and per-

appearing in any other dream. A network

son-like entities such as mythological fig¬

constructed from the first few dreams of

ures and talking animals.

a series would consist mostly of islands.

Social networks of characters in dreams

After many dreams, most points become

have some of the same properties as social

connected in a large subnetwork, called the

networks of people in waking life. A well-

giant component. Because the dreamer is

known property of a friendship network

in every dream, illustrating her would clut¬

is a short average path length, sometimes

ter the network, so she is not represented.

dubbed six degrees of separation: Between

An exception is made when the dreamer is

two arbitrarily chosen people one can usu¬

present in a metamorphosed form, as in a

ally find a short path of friends and acquain¬

dream in which a woman dreamt she was

tances. A network formed by connecting

a little boy. Metamorphosed forms of the

points together at random also tends to

dreamer are represented by points.

have short average path length. Perhaps

Dream reports of Arlie and many other

surprisingly, the average path length in a

people are available on the DreamBank

typical waking-life social network is ap¬

Web site (Schneider & Domhoff, 2011).

proximately the same as that of a random

To construct the network one needs a re¬

network with the same number of points

liable way to determine who is present in

and lines. Another property of waking-life

a dream. There is no way to learn who a

social networks is high clustering: If A is

dreamer is dreaming about by examining

a friend of B and B is a friend of C, then A

brain waves or other external measures;

and C tend to be friends of each other. In a

one must consider what the dreamer says.

random network, clustering is low; A and C

In a classic work, Calvin S. Hall and Rob¬

are joined by a line with the same probabil¬

ert Van De Castle developed a system for

ity whether or not A and C are both joined

coding contents of dream reports (Hall &

to B by lines. The two properties of short




Social Network Analysis of Dream Content

average path length and high clustering do

to other points. One consequence is that a

not ordinarily occur in the same network.

short path between two points can usually

Networks with both properties are special,

be formed by starting at one point, going

and are called small world networks.

to a hub, and then proceeding to the other

Many, but not all, dream social networks

point. Degrees in both waking life and

are small world networks. For the net¬

dream social networks typically have Zipf

work in the dream social network image,

degree distributions.

the average path length is short, near that

One might think that a dream social net¬

of a comparable random network. But its

work is simply a copy of the dreamer’s

clustering is high, far greater than that of

waking-life social network, and thus they

a comparable random network. This net¬

have properties in common. But this can¬

work is a small world network.

not be the explanation. Characters in dream

A dream social network that is not a

social networks include celebrities and car¬

small world network is that of the engine

toon characters, not people the dreamer in¬

man, given this name because of the prev¬

teracts with while awake. Sometimes one

alence of locomotives in his dreams. The

character metamorphoses into another, not

network has many sequences where A is in

an event of waking life. A poignant demon¬

a dream with B, and B is in a dream with C,

stration that dream- and waking-life social

but A and C are not in a dream together.

networks differ is that the person occurring

Triangles tend not to be completed and the

most often in the dreams of Merri is her sis¬

clustering is near that of a comparable ran¬

ter, but her sister was killed in an accident

dom network. The average path length is

three years before Merri began her dream

short, a little larger than that of a compa¬


rable random network.

A more likely explanation of the com¬

Another property of social networks has

mon properties of dream- and waking-life

to do with the number of points a given

social networks is that the dreamer’s as¬

point is connected to. The number of points

sociative memory has the properties of

connected by a line to a given point is the

short pathways, high clustering, and a

degree of the given point. Many quantities

Zipf degree distribution. Human semantic

in nature follow a normal distribution, with

networks, such as a network made from

middle values the most common and high


and low values uncommon. Degrees in so¬

(Steyvers & Tenenbaum, 2005). Charac¬

cial networks do not follow a normal dis¬

ters in dreams correspond to concepts of

tribution. The lowest values are the most

people and the concepts include mytho¬

common and the highest values the least

logical figures, talking animals, cartoon

common. The probability distribution of

characters, and so on. Characters occur in

degrees is a Zipf distribution, sometimes

a dream together when they are associated

called a power law. The higher a degree

somehow in the dreamer’s memory. One

the less likely it is to occur; the probability

piece of evidence for this is that when an

a degree is k is inversely proportional to k.

entity metamorphoses into another entity,

A few points, hubs, are highly connected

the entities tend to be conceptually close.





Sound-Work: The Neglected Sense in Working with Dream Images

People metamorphose into other people more often than into animals, and more often into animals than into objects (Schweickert & Xi, 2009). Deceased people and those who have moved away continue to appear if they are associated with peo¬ ple currently in the dreamer’s waking-life social network. In REM sleep the dreamer follows associative pathways, and the


Schweickert, R., & Xi, Z. (2009). Metamor¬ phosed characters in dreams: Constraints of conceptual structure and amount of theory of mind. Cognitive Science, 34, 665-684. Steyvers, M., & Tenenbaum, J.B. (2005). The large-scale structure of semantic networks: Statistical analysis and a model of semantic growth. Cognitive Science, 29, 41-78. Watts, D. J. (2003). Six degrees: The science of a connected age. New York: W.W. Norton.

structure of these pathways becomes vis¬ ible in the dream social network. One of many open questions is why some dream social networks have high clustering and some do not. To answer such questions we will need more infor¬ mation about the daily lives of dreamers, to compare dream- and waking-life so¬

Sound-Work: The Neglected Sense in Working with Dream Images Sound Awareness

cial networks. Sleep is known to be im¬

Sound is the most direct, immediate, ef¬

portant for memory consolidation, and

ficient, and effective way to perceive and

it is likely that the contents of dreams

transform that which vibrates with, with¬

are manifestations of some kind of mem¬

out, and within us. The word sound, let us

ory processing during sleep. Observing

recall, also means healthy, well, whole¬

how dream social networks change over

some, robust, and is often used to imply

periods of time may shed light on this

vigor, strength, sensitivity, energy, sturdy,


intact, whole. Richard Schweickert

References Hall, C.S., & Van de Castle, R. (1966). The content analysis of dreams. New York: Appleton-Century-Crofts. McNamara, P., McLaren, D., Smith, D., Brown, A., & Stickgold, R. (2005). A “Jekyll and Hyde” within: Aggressive versus friendly interactions in REM and non-REM dreams. Psychological Science, 16, 130-136. Schneider, A., & Domhoff, G.W. (2011). DreamBank. Retrieved from http://www. dreambank.net/ Schweickert, R. (2007). Properties of the organizatiorf of memory for people: Evidence from dream reports. Psychonomic Bulletin & Review, 14, 270-276.

While sound—the audible aspect of vi¬ bration—accompanies all movement and serves to orient us, and much more, we tend to take it for granted in our lives, and certainly in our dreamwork. We generally take image as primary—but, let us not over¬ look that as vibration, sound is there from the beginning (notice the role of sound in creation myths from around the globe), and comes with each and every encounter. All meetings involve, reflect, and pro¬ duce new sounds. At the most basic physi¬ cal level, sound travels in waves that affect and have an effect on the bodies they touch, generating further vibrations. We respond when touched.




Sound-Work: The Neglected Sense in Working with Dream Images

Sound has a double effect, literally it dis¬

Automatic aspects of our being ap¬

solves (releases, breaks, cleanses, opens)

pear in the sounds that we unexpectedly

and it coagulates (shapes, limits, orga¬

and involuntarily find ourselves emitting,

nizes, creates)—structuring new and con¬

often revealing something essential to

stantly changing forms. Brought into being

the emotional—inner—sense of what we

by movement, sound also brings forth new

are saying. For those interested in uncon¬


scious manifestations and synchronicities,

While much therapeutic and spiritual

our voice offers vast and multifaced mir¬

work is being done with sound (music, ton¬

rors to help us recognize all sorts of uncon¬

ing, singing), surprisingly little attention

scious phenomena. Becoming sensitive to

has been given to linking sound-work to

the sounds in our voice can guide us in re¬

images from our dreams (and lives). Here,

fining how we perceive and react reflex-

a case is made for developing an awareness

ively, in how we think, feel, see, and take

founded on hearing, emitting, and listening

ourselves into the world.

experiences. Whether or not we are aware

All the more influential when unnoticed,

of sound—or participate consciously in it

sounds can dominate our relationships with

as a specific sense—it is constantly giving

others. We have only to note carefully what

form to invisible and unknown aspects of our lives.

we communicate and convey with the tone, speed, volume, intention, attitude, energy,

The potential of this proposal is revealed

sense, and direction of what we say. In¬

in what happens to the life of a person that

dependently of the meanings we attach to

explores and discovers him—or herself by

words, sounds touch us directly and often

working with vocal awareness, mindful¬

more deeply. How something is said usu¬

ness, and practice. This proposal wants to

ally carries much more meaning than what

incite interest and practice with the outer

is actually said. And it seems evident that

and inner sounds that come along with the

we frequently react and respond more to

images in our dreams (and lives).

the tone and rhythm of what is said than to the content itself. The challenge is to develop a heightened

Vocal Sound Awareness

awareness of the medium we call sound: It is not difficult to hide from our sounds.

around (outside) us, and within us.

Actually hearing the sounds we emit tends to be disconcerting; it makes ev¬ ident the scopes and limitations of our

Sound-Work and Dreams

defense mechanisms. Listening to the

Outer and inner happenings meet in our

sounds that we emit frequently has the

dream images, triggering vibrations at all

effect of deconstructing the mind’s be¬

levels of our being. This proposal involves

lief systems,


resonating with the images that affect, as

conscious) somatic, emotional, mental,

much as reflect, our different realities. The

and spiritual phenomena instantly more

notion of resonance implies that vibrat¬


ing with something triggers movements to

making automatic

Sound-Work: The Neglected Sense in Working with Dream Images


differentiate, and invites us to enter a met¬

generating images. New images inevitably

aphorical experience, relevant to multiple

appear and transform with sound, reveal¬

levels of our inner and outer reality.

ing the primary, intimate, dynamic, and

Like life itself, dreams present us with scenarios, which at any given moment con¬

transformative relationship between sound and image.

ceal as much as they reveal. A dream scene is a place in which something is constel¬ lated; different aspects are highlighted as

Sound-Work and Imagination

they come together to form a momentary

Neither images, nor our phenomenologi¬

whole. Scenes in dreams offer specifically

cal experience of them are in themselves

different perspectives that somehow draw

perceptions. Rather, they are the result of

our attention to at least one nodal moment

an imaginal activity that affects and chal¬

in the dream sequence, in which a cer¬

lenges us to question our perceptions. In

tain tension—or dissonance—signals that

the first paragraph of his book Air and

something vital is at stake.

Dreams, Gaston Bachelard writes: “The

Dreams can be imagined as invitations

imagination ... deforms what we perceive;

to discover perspectives that may be new

it is, above all, the faculty that frees us from

and different, and even alien to those of the

immediate images and changes them. If

ego; this is why our approach to dreams

there is no change . . . there is no imagina¬

should not be ego-syntonic. My proposal is

tion; there is no imaginative act.”

to use sound as a means to access, reveal,

Dream images are not meant to be

and connect with the dream experience

taken literally, concretely, objectively,

beyond the ego’s control. Sound-work im¬

nor to be translated into the language of

plies nurturing a palpable relationship with

the ego’s well-rehearsed day-world per¬

the invisible.

spectives (usually designed, as we know,

Describing a sound without having

to avoid fears of some kind of pain or

heard it is like describing an image with¬

discomfort)—nor to be converted, through

out having seen it. We must literally emit


a sound to actually hear and listen to it. Let

than what they simply are—very precise

us give importance to the sounds that come


to being through our mouths.




While taking the literalness away from

That the sounds in a dream image are

words and content both awakens and weak¬

sometimes not easily recognized does not

ens our defenses, it also allows the person

mean that they are not present in the telling

to focus with increasing concentration on

(and reliving) of the dramatic scenes in the

listening for the intention and emotional

image, and in the experience of the tension

tone and sense of what is being expressed

within the images themselves. This tension

through the sound.

is made palpable and brought even more into life with sound awareness.

In themselves, images manifest, involve, express, and contain sound. Particular

Most significant is that sound is a sim¬

scenes are breeding grounds for new im¬

ple, basic, obvious, and immediate way for

ages to gestate and take form. Sound-work




Sound-Work: The Neglected Sense in Working with Dream Images

activates and releases this inherent poten¬

most of us only sporadically notice sound

tial in dreams.

in our dreams. (2) Recognizing and explor¬

As living metaphors, dream scenarios

ing the sounds that correspond with spe¬

are a medium for presenting the dreamer

cific actions in our dream image sequences,

with what is called for to bring new move¬

and the resonance of this in our present-

ment to his or her life. Sound-work facili¬

day lives. (3) Working with how we tell the

tates this; certain moments in some images

dream to others. (4) Giving vocal form to

are setups for sound experiences.

the emotions awakened by our attending to

Sound-work frees us of literal perspec¬

the images presented by the dream.

tives and personal needs for concluding

In addition, it is critically important to

and resolving things; it opens new ways of

work consistently to recognize and put all

imagining, and allows the dream images to

sorts of judgments and prejudices to one

reveal aspects and perspectives alien to the

side, and to remember that the goal is not a

ego’s natural tendencies and inclinations.

cathartic experience. Instead, this proposal

The sounds implicit to particular scenes in

aims at connecting and relating ever more

the dream—and the sounds we emit while

deeply to the issues that call attention to

resonating with its images—are our prima

themselves in and through our dreams.


Through sound-work, the inner sense

More than wanting to be understood,

of things becomes more palpable and con¬

images that come back in dreams—and

sciously experienced, allowing the person

stay with us—beg to be reexperienced.

to be constructively transformed by taking

Sound-work inevitably makes this happen,

into account concerns that go beyond his

consistently dissolving our identifications,

or her ego’s reach. Emitting sound gener¬

attachments, and interpretations, which

ates different kinds of inner movements.

usually translate into the meanings that

Sound forces us to breath, to take in, and

we give to our dreams. At the same time,

to release—it involves our physical, emo¬

vital issues take on new forms: something

tional, mental, and spiritual bodies in a

unexpected coagulates. As the alchemists

wide range of dynamics and processes.

practiced and proclaimed for centuries:

While we may not notice the sounds that

dissolve that which is coagulated and co¬

invariably accompany our dreams, it is vir¬

agulate that which is dissolved.

tually impossible to listen to the sounds we

Experiencing dream images through

emit without indelibly altering our experi¬

sound-work leaves multiple impressions

ence of the initial images, and generating

in its wake, making it very difficult for all

new images. Trying to emit the sounds that

those involved to find themselves in a situ¬

we hear in our dreams—or in our working

ation similar to the sound experience with

with them—inevitably makes us experi¬

the dream without reacting and respond¬

ence something essential to the sound, and to our lives.

ing in surprisingly creative and construc¬ tive ways.






This particular sound-work proposal en¬

sciously emitting the sounds that appear

compasses: (1) Going beyond the literal, as

in (and with) the images in their dreams.

Sound-Work: The Neglected Sense in Working with Dream Images


As if there were a kind of knowing that to

led him to allow the sounds that he could

emit the sound is to experience it. Not al¬

not stop from hearing inside himself to

lowing the sound to take actual form is to

emerge from the depths of his being and

somehow deny a highly dynamic aspect of

take form as sound.

it. The more willing a person is to allow the

The exercise took him beyond the reach

sounds that emerge from deeply within to

of his ego’s limits and control, and through

appear and take form, the deeper the trans¬

a series of vivid experiences of sensations,

formative experience.

emotions, feelings, thoughts, memories, associations, and unexpected new images, which in the end freed him of his inner

The Imagination Is Vivified by Sound-Work


The call is to allow dream images to be¬

Wolfsohn had discovered that sustaining a

come deeply rich day-world experiences.

focused vocal sound long enough, led be¬

More than an idea about something, sound-

yond cathartic moments—and beyond all

work is in itself an experience.

that we think and feel that we know of our





This proposal, therefore, is an invitation

cry (be it one of joy, of lament, of com¬

to allow sound-work to convert certain sce¬

plaint, of desire)—brings more than relief

narios in our dreams into present-day lived

to a condition: it actually transforms it.

experiences: relevant to ongoing cycles of

Alfred Wolfsohn was transformed, and

transformation, to our creativity, and to

discovered the power that comes with al¬

fundamental well-being in our everyday

lowing the dissonant, uncomfortable, pos¬


sibly horrible sounds that unexpectedly emerge from the depths of our souls to

Source of Inspiration: Alfred Wolfsohn (1896-1962)

guide us into fundamental shifts in our relationship with ourselves and with the world around us.

A medic during the World War I, Alfred

This vocal sound-work proposal honors

Wolfsohn was a man haunted by night¬

Alfred Wolfsohn and attempts to further

mares and auditory hallucinations, cer¬

his insights with practice. Sven Doehner

tainly influenced by his terrible memories of carrying wounded men, howling with pain, away from combat zones on his stretcher. With no anesthesia to diminish their suf¬ fering, we can only imagine the sounds that emerged from the agony of those desper¬ ate men. Long after the war, these primi¬ tive piercing sounds continued to haunt Wolfsohn, not letting him be. Until the day when what we could only call desperation,

See also: entries related to Dream Content

References Bachelard, G. (1999). Water and dreams: An essay on the imagination of matter (3rd ed.) (Trans. E. R. Farrell). Bachelard Translation Series. Dallas, TX: The Dallas Institute of Humanities and Culture. Hillman, J. (1979). The dream and the under¬ world. New York: HarperPerennial.




Space in Dreams

Ihde, D. (2007). Listening and voice, phenomenologies of sound. Albany: State University of New York Press.

During any stage of sleep, activation of the parietal lobe might indicate the pres¬ ence of spatial experience. In a study of several hundred neurological and neuro¬

Space in Dreams

surgical patients, Solms (1995) observed that patients experiencing disturbances in

Space is generally regarded as an expanse

waking visual-spatial abilities as well as a

measurable in terms of known dimensions:

complete loss of dreaming had brain dam¬

height, width, depth, and time, absolutely

age located in the parietal region. During

or relatively. While dreaming, the dreamer

REM sleep, positron emission tomography

produces visual abstractions in space. Pri¬

(PET) and statistical parametric mapping

marily thought-like, experiences in dreams

indicated activation of the right inferior pa¬

might be accompanied by visual abstrac¬

rietal lobe (Maquet et al., 1996). A PET

tions in space, of which the dreamer might

scan study indicated some activation in the

or might not be aware; there might be an

parietal cortex during REM sleep (Maquet,

imaginary sphere of the body that provides

2000). Based on the presence of positive

an orientation to space; the symmetry of

electroencephalograph (EEG) brain poten¬

spatial experiences while awake might

tials, the brain’s parietal-occipital area be¬

be contracted, expanded, or transformed

came active immediately following REM

while dreaming.

sleep (Ogawa, Nittono, & Hori, 2002).

From the theoretical perspective of quan¬

Brenneis (1970), Foulkes, Pivik, Stead¬

tum physics, Bohm (Briggs & Peat, 1987)

man, Spear, and Symonds (1967), and

proposed that space, time, and matter are

Trosman, Rechtschaffen, Offenkrantz, and

abstractions that unfold from the implicate

Wolpert (1960) have all researched the

order—a vast, boundless energy space—

subject of spatial experiences in dreams.

and surface, become explicit, in the ex¬

Brenneis (1970) studied the dreams of

plicate order. In accordance with Bohm,

183 male and female college students.

Ullman (1987) suggested that dreams vac¬

From a spatial perspective, he concluded

illate between the two orders and therefore

that males had a tendency to structure the

might present spatial and temporal content

space in their dreams in terms of extension

regarded as unusual to the dreamer.

and separateness from others and females

Snyder and Gackenbach (1991) dis¬

in terms of closeness and intimacy. Erik-

cussed spatially oriented body movement,

son (1954) believed there were aspects of

a function of the vestibular system and the

dreams that could be arranged in a con¬

essential role of space in dreams. They re¬

figuration and manifest in one dream or a

ferred to the intense activation of vestib¬

series of dreams. He' identified spatial as

ular nuclei in the brain stem during rapid

one of seven possible manifest configura¬

eye movement (REM) dreaming as well

tions, along with verbal, sensory, tempo¬

as the likelihood of the predominance of

ral, somatic, interpersonal, and affective.

vestibular-bound imagery and movement

Erikson characterized the spatial aspect

patterns during dreaming.

of dreams according to spatial extension

Space in Dreams


and motion. When analyzing Freud’s Irma

Brenneis (1970), Foulkes et al. (1967),

dream, Erikson interpreted festivity in the

and Trosman et al. (1960) have all re¬

dream as a reflection of affect, and he asso¬

searched the subject of spatial experiences

ciated festivity affect with spaciousness, a

in dreams and have reported that dreamers

spatial variable. He interpreted urgency in

experience space, although the researchers

a dream as a reflection of affect, and he as¬

themselves, not the dreamers, made this de¬

sociated urgency affect with constriction, a

termination and described the experiences.

spatial variable.

Tyburczy (2008) requested 28 dreamers

Foulkes et al. (1967) categorized spa¬

to recall and describe spatial experiences in

tial and temporal experience together as

their dreams in their own words as well as

a dimension of dreams. After independent

by selecting and using spatial terms from

raters reviewed the dreams of 32 boys,

22 spatial parameter, spatial experiential,

the researchers reported that the spatial

and spatial view descriptor categories con¬

and temporal dimension was identified in

tained in a content validated instrument,

76 percent of dreams. Trosman et al. (1960)

Spatial Questionnaire Selections 2 (see

considered spatiality in dreams in terms of

Table 9).

spatial expanse. The researchers assessed

The dreamers were also requested to

the dreams of two participants over a pe¬

select terms from emotions categories

riod of 34 nights in a sleep lab after record¬

contained in Emotions Questionnaire Se¬

ing an average of four or five dreams per

lections that was adapted from Goleman’s

night from each participant. Each dream

(1995, p. 289) research on emotions to re¬

was assessed on the basis of 12 dimen¬

call and describe emotional experiences

sions: spatial expanse, hedonic tone, ex¬

in their dreams. Spatial parameter catego¬


ries include density, depth, dimension in



interpersonal involvement,



space, direction, distance, energy, height,

matic coherence, plausibility, elaboration,

position in space, shape, spatially unusual

resolution, and success (p. 603). Defined

or bizarre, time, and width. Spatial expe¬

in terms of geographical space, spatial ex¬

riential categories include controlled in

panse was rated as low when the space was

space, supported in space, contained in

considered constricted and as high when

space, free of gravity in space, grounded

the space was considered expansive. Tros¬

in space, motion in space, and precarious

man et al. (1960) reported a high positive

position in space. Emotions categories in¬

correlation between spatial expanse and

clude anger, sadness, fear, enjoyment, love,

the dimensions of excitation, referring to

surprise, and disgust. Response percent¬

degree or charge of emotional expression;

ages for all research questions indicated

activity, referring to amount of kinetic ac¬

that participants described experiences in

tivity; interpersonal involvement, referring

dreams in terms of the spatial parameter

to degree of emotionally charged interac¬

categories of density (48.5%),, distance

tion; clarity & referring to vividness and lack

(48%), and position in space (48%), and in

of ambiguity; and elaboration, referring to

terms of enjoyment (46.4%) from the emo¬

the quality and diversity of dream content.

tions categories. Significant relationships


Table 9: Spatial Questionnaire Selections 2 Area: spatial parameters Spatial parameter categories (bold); terms (not bold) Density: cramped; cluttered; compacted; compressed; crowded; crushed; dense; full; heavy; open; packed; spacious; thick; uncluttered; vacant; voluminous Depth: abyss; bottomless; deep; downward; fathom; shallow; steep Dimension in space: inner space; outer space Direction: across; backward; down; east; forward; north; northeast; northwest; parallel; perpendicular; sideways; south; southeast; southwest; up; upward; west Distance: away; close; distant; extension; far; gap; long; near; nearby; space; span Energy: electrical; gaseous; solid Height: apex; ceiling; elevation; heavenward; high; lifted; lofty; low; peak; pinnacle; short; summit; tall; top; upward; vast; vertical; zenith Position in space: above; adjacent; behind; below; beneath; beside; extended; in; in front of; in the back; in the front; laterally; level with; location; lower; out; over; parallel with; point; positioned; prone; traversal; under; underneath Shape: circle; crescent; ellipse; parallelogram; polygon; quadrilateral; rectangle; rhombus; sphere; spiral; square; star; trapezoid; triangle Size: big; breadth; huge; immense; large; microscopic; minute; small; vast; voluminous Spatially unusual or bizarre: channels switching; metamorphosis; superimposition; transfiguration; transformation Time: accelerated; back; delayed; eternal; fast forward; forward; future; infinity; interval; past; present; rewind; timeless Width: expanse; horizontal; narrow; wide

Area: spatial/experiential Spatial/experiential categories (bold); terms (not bold) Controlled in space: confined; constricted; harnessed; held down; impacted; manipulated; pinned down; pressured; smothered; suffocated; surrounded; trapped Supported in space: boosted; carried; elevated; extended; held up; hovering; lifted Contained in space: bound; closed-in; cramped; crowded; embodied; enclosed; entombed; encapsulated; immersed; in; sheltered Free of gravity in space: boundless; floating; flying; weightless Grounded in space: grounded; rooted; secured Motion in space: ascend; bouncing; bounding; descend; elevated; falling; flung; glide; out of control; plummeted; propelled; pulled; pushed; raised; released; rising; rotating; sinking; soaring; spinning; spiraling; swaying; swinging; swooping; thrown; thrust; transported; trapped; turning; unleashed; wedged Precarious position in space: bottomless; claustrophobic; cornered; dangled; frozen; hanging; paralyzed; perched; plummeted; suspended; tottering; unbalanced

Area: spatial view descriptors Spatial view categories (bold); terms (not bold) Obstructed/unobstructed: close; clear; cluttered; constricted; crowded; endless; expansive; far; horizon; near; opaque Illumination: bright; dark; dim; light; well lit Note: Developed by Susan M. Tyburczy, 2007-2008.

Space in Dreams


at the .01 level occurred between terms in

Sixteen participants reported observ¬

categories reported in dreams, such as di¬

ing themselves as observers in their own

rection and time, dimension in space and

dreams from 33 different positions in

spatially unusual or bizarre, size and time,

space grouped by the researcher into posi¬

supported in space and contained in space,

tion headings, including above, adjacent,

energy and precarious position in space,

below, level with, and multipositions.

and depth and sadness.





In response to specific interview ques¬

human experiences with space in dreams

tions, 27 of 28 dreamers reported experi¬

might include spatial experiences in pre-

encing space on their own, 21 with other

cognitive, lucid, or telepathic dreams or

people, 8 with living things, 20 with ob¬

nightmares, spatially bizarre aspects of

jects, and 18 with a visual-perceptual

dreams, or the phenomenon of dream¬

view. While experiencing space on their

ers observing themselves as observers

own, participants most frequently reported

from spatial perspectives. The relationship

density (82.1%) and position in space

between space and time in dreams is also a

(82.1%) from the spatial parameters cat¬

potential research topic. The roles that spa¬

egory, motion in space (71.4%) from the

tial experiences in dreams play in problem

spatial/experiential category, and enjoy¬

solving or memory-consolidation processes

ment (75%) and fear (75%) from the emo¬

might be explored.

tions category. While sharing space with

cal studies concerning the dreaming brain

other people in recalled dreams, partici¬

while experiencing space in specific situa¬

pants most frequently reported distance

tions are also suggested for future research.

(75%) from spatial parameters, contained

Susan M. Tyburczy

Further neurologi¬

in space (46.4%), controlled in space (46.4%), and motion in space (46.4%) from spatial/experiential, and fear (60.7%) and love (60.7%) from emotions. While sharing space with living things other than people in their dreams, participants most frequently recalled and reported experi¬ encing distance (75%) from spatial pa¬ rameters, controlled in space (17.9%), and contained in space (17.9%) from spatial/ experiential, and surprise (21.4%) from emotions in recalled dreams. While shar¬ ing space with objects in their recalled dreams, participants most frequently re¬ called density (64.3%) from spatial pa¬ rameters, contained in space (39.3%) from spatial/experiential, and enjoyment (53.6%) from emotions.

References Brenneis, C.B. (1970). Male and female ego modalities in manifest dream content. Jour¬ nal Abnormal Psychology, 76, 434-442. Briggs, J., & Peat, F. D. (1987). Interview, David Bohm. Omni, 9, 68-76. Erikson, E. (1954). The dream specimen of psy¬ choanalysis. J Am Psychoanal Assoc, 2-5. Erikson, E. (1979). The dream specimen of psychoanalysis. In R. P. Knight & C.R. Friedman (Eds.), Psychoanalytic psychia¬ try and psychology: Clinical and theoretical papers (pp. 131-173). New York: Interna¬

tional University Press. Foulkes, D., Pivik, T., Steadman, H.S., Spear, P. S., & Symonds, J.D. (1967). Dreams of the male child: An EEG study. Journal of Abnormal Psychology, 72, 457-467.




Sports and Dreaming

Goleman, D. (1995). Emotional intelligence. New York: Bantam Books.

One study, for example, demonstrated that

Maquet, P. (2000). Functional neuroimaging of normal human sleep by positron emission tomography. Journal of Sleep Research, 9, 207-231.

ing activities (e.g., car driving) is related

Maquet, P., Peters, J.M., Aerts, J., Delfiore, G., DeGueldre, C., Luxen, A., & Franck, G. (1996). Functional neuroanatomy of human rapid-eye-movement sleep and dreaming. Nature, 383, 163-166. Ogawa, K., Nittono, H., & Hori, T. (2002). Brain potentials associated with the onset and offset of rapid eye movement (REM) during REM sleep. Psychiatry and Clinical Neurosciences, 56, 259-260. Snyder, T. J., & Gackenbach, J. (1991). Vestibu¬ lar involvement in the neurocognition of lucid dreaming. In J. Gackenbach & A. Sheikh (Eds.), Dream images: A call to mental arms (pp. 55-78). Amityville, NY: Baywood. Solms, M. (1995). New findings on the neu¬ rological organization of dreaming: Impli¬ cations for psychoanalysis. Psychoanalytic Quarterly, 64, 43-67. Trosman, H., Rechtschaffen, A., Offenkrantz, W., & Wolpert, E. (1960). Studies in psy¬ chophysiology of dreams. Archives of Gen¬ eral Psychiatry, 55, 602-607. Tyburczy, S.M. (2008). Recall of space in dream reports and exploring dreaming from a spatial perspective. PhD diss., Saybrook

Graduate School and Research Center, ProQuest (AAT 3379048).

the amount of time spent in different wak¬ to the occurrence of the corresponding activity in dreams; that is, the continuity hypothesis is largely supported by studies investigating different types of waking-life experiences, for example, divorce, stress, life events, on dream content (for an over¬ view see Schredl, 2003). For the topic of sports, several pilot studies (for an over¬ view see Erlacher & Schredl, 2004) and single case studies (e.g., Domhoff, 1996) in athletes indicate that the continuity is also present for athletic activities—that is that frequent practicing during the day is reflected in the heightened occurrence of sport dreams. Up to now, only three studies (Erlacher & Schredl, 2004, 2010a; Schredl & Erlacher, 2008) investigated the relationship between daytime sport activi¬ ties and dreams in a systematic way. In the first study, Erlacher and Schredl (2004) demonstrated in a dream-diary study that sport students dream more often about sports (active participation and gen¬ eral sport themes) than do psychology students, reflecting sport students’ engage¬ ment in sport activities and sport theory. In the second study, Schredl and Erlacher (2008) showed that the percentage of sport

Ullman, M. (1987). Wholeness and dreaming. In B.J. Hiley & F. D Peat (Eds.), Quan¬

dreams for sport students was directly re¬

tum implications: Essays in honor of David

lated to the amount of time spent with wak¬

Bohm (pp. 386-395). New York: Routledge

ing sport activities. As the group factor was

& Kegan Paul.

still significant after controlling for amount of practicing sport, it was hypothesized

Sports and Dreaming

that sport students talk and think about sports more often and may be more emo¬

The continuity hypothesis in dream re¬

tionally involved in sports than psychol¬

search suggests that the dream content re¬

ogy students. In a large sample of German

flects waking experiences (Schredl, 2003).

athletes (N = 632; study 3), the frequency

Stage behind the Eyes—Theater and Dreams

of sports dreams was very high, almost 90 percent of the athletes reported this kind of dream (Erlacher & Schredl, 2010a). Within the athletes the frequency of sport dreams was associated with dream-recall frequency (entered as a control variable into the analysis), the number of practice hours per week, and the number of competitions/ games during the last 12 months. This find¬ ing indicates that the continuity not only reflects the amount of time spent with the particular activity during the day but also


Erlacher, D., & Schredl, M. (2010b). Practicing a motor task in a lucid dream enhances sub¬ sequent performance: A pilot study. Sport Psychologist, 24, 157-167. Schredl, M. (2003). Continuity between wak¬ ing and dreaming: A proposal for a math¬ ematical model. Sleep and Hypnosis, 5, 38-52. Schredl, M., & Erlacher, D. (2008). Rela¬ tionship between waking sport activities, reading and dream content in sport and psy¬ chology students. Journal of Psychology, 142, 267-275.

might reflect worries and stress about per¬ forming experienced by the athletes. To summarize, sport is reflected in the

Stage behind the Eyes— Theater and Dreams

dreams of persons actively engaged in this waking-life activity. In the context of

Since the dawn of the Western drama in

completion, it would be very interesting to

ancient Greece, dreams have featured fre¬

study whether dreams reflect worries or

quently in and been used as inspiration

even sport-related nightmares might have

for plays and other dramatic performance

an effect on the athletes’ performance. As

pieces. In this entry, I will touch on some

there is evidence from case reports and a

examples and discuss why the relationship

pilot study that athletes can train their sport

between dreams and theater seems so natu¬

within lucid dreams (Erlacher & Schredl,

ral. I will end with a suggestion for further

2010b), it would be very promising to train

exploration of dream material in dramatic

athletes using lucid-dreaming techniques

writing and performance.

to increase their performance.

Dreams have found their way into sto¬

Michael Schredl and

rytelling from earliest times. From Gil-

Daniel Erlacher

gamesh’s dream of a great axe to Jacob’s stairway to heaven dream in the Bible and


the dreams of Agamemnon and Penelope

Domhoff, G.W.

in Homer’s Iliad and Odyssey, dreams

(1996). Finding meaning in dreams: A quantitative approach. New York: Plenum Press.

Erlacher, D., & Schredl, M. (2004). Dreams reflecting waking sport activities: A com¬ parison of sport and psychology students. International Journal of Sport Psychology, 35, 301-308.

Erlacher, D., & Schredl, M. (2010a). Frequency of sport dreams in athletes. International Journal of Dream Research, 3, 91-94.

have always served to highlight important moments in narratives—the prophetic, the fantastic, the seemingly prosaic. The first clear instance of a dream ap¬ pearing in a theater piece is Atossa’s dream in Aeschylus’ The Persians (first performed in 472 BCE). Since that time theatrical storytellers have frequently used dreams as plot points, framing devices, and




Stage behind the Eyes—Theater and Dreams

stylistic models. Dreams and dream refer¬

In Richard III (the play in which the word

ences appear more than 200 times in works

dream appears most often—26 times),

by Shakespeare, most significantly perhaps

Clarence recounts a harrowing dream of

in Richard III and A Midsummer Night’s

drowning, which becomes a metaphor for

Dream. They appear in the works of other

his guilt and a premonition of his actual

dramatists as various as Calderon (Life Is

fate. Brakenbury, listening to the descrip¬

a Dream), Strindberg (A Dream Play), and

tion, is terrified, as Shakespeare means

J.B. Priestley (the “Time Plays”).

us to be as we empathize with Clarence’s

One reason for the connection between

dire and emotion-filled predicament. Other

dreams and theater is that in both we read¬

dreams are woven contrapuntally through

ily accept that anything is possible. In

the drama as enticements to action or in¬

dreams as in plays the prophetic and the

action, as punishments and rewards, re¬

magical, no matter how outlandish or ab¬

minding us of the ever-present interplay of

surd, can seem true and real, and the com¬

opposites and contradictions in our lives.

monplace significant.

In A Midsummer Night’s Dream, the

Another reason for the connection is

emphasis is on the comical, sexual, and

that in both the theater of sleep (Almansi

transformative qualities of dreams and the

& Beguin, 2009) and the playhouse we can

emotions they provoke. The play can be

experience an intensity of emotion that in

seen as a series of dreams within dreams,

our waking lives we would try to avoid as

into which we are invited to enter willingly

embarrassing or outrageous. No performer

and from which, having learned something

wants to portray a character who is slightly

about ourselves, we awaken changed. Bot¬

homicidal, a tiny bit in love; dramatic char¬

tom’s famous dream of becoming a donkey

acters tend to feel strongly and behave

turns out to be partly real, as does Hermia’s

boldly, often irrationally. Hence powerful

about a serpent, with its implications of

dream stories can serve as excellent mod¬

sexuality, temptation, and danger. In fact

els for drama. As Jon Lipsky (2009) writes

all the lovers’ actions are laced with im¬

in his wonderful book on group dream en¬

ages of good and bad dreams which un¬

actment, Dreaming Together, “We experi¬

leash emotions and behavior that would

ence in sleep the passions of a Cyrano, of

otherwise be prohibited. Even Titania,

a Hedda Gabler, of a Richard III. We be¬

Queen of the Fairies, is herself bewitched

come a thief, a movie star, a randy lover”

by the dream image of falling in love with

(p. 14). The continuing success of the the¬

an ass (Bottom as donkey). The play’s end¬

ater confirms our urgent desire to experi¬

ing leaves the characters finally awake and

ence the full range of emotions that life has

the audience with the wistful feeling of loss

to offer, and dream material can give us the

that so often follows a wonderful dream.

dramatic license to incarnate those emo¬ tions on stage and examine them.

Playwrights have often appropriated the elasticity of time and space that we

As in so many areas of dramaturgy,

feel in dreams. J.B. Priestley (1937) wrote

Shakespeare realized the usefulness of

his Time and the Conways to explore the

dreams as drama more fully than anyone.

ideas of circular or serial time as put forth

Stage behind the Eyes—Theater and Dreams


by amateur dream researcher J. W. Dunne

can help break through barriers of per¬

(1927) in his essay An Experiment with

formance anxiety to enhance the truth¬

Time, which argues that precognitive im¬

ful enactment of strong emotional states.

ages in dreams suggest that time is not

Performers can consciously draw on and

linear. Priestley believed in Dunne’s con¬

effectively embody the vivid scenes and

clusions and saw great dramatic possi¬

feelings revealed in dreams, combining

bilities in them. Presenting the Conway

them with other story elements to great

family, happy and unified after World War


I but tom apart on the eve of World War II,

It is important to touch on the question

Priestley manages to combine with great

of how to distinguish between dramati¬

force and emotion the family’s story, the

cally useful dream material and that which

politics and social milieu of England be¬

seems only the meaningless flotsam and

tween the wars, and his ideas about time.

jetsam of our ever-crowded minds. The an¬

As in dreams, images in his drama both

swers are certainly as varied and layered

embody meaning and obscure it, causing

as the people and dramatic pieces that at¬

us to consider the more closely what we

tempt to incorporate dream imagery, and it

have seen.

would be useless to try to lay down strict

August Strindberg’s (1919) theatrical explorations are described in his preface

rules. However, there are solid principles that can act as guides.

to A Dream Play, where he writes that he

In my own work as a theater direc¬

“sought to imitate the disjointed yet seem¬

tor, I have often used dream material in

ingly logical shape of a dream. Everything

company-devised work. In doing so I have

can happen, everything is possible and

been careful first to define a clear theme

probable. Time and space do not exist; the

for the piece and then to choose or reject

imagination spins, weaving.. .a mixture of

dream images or sequences based on how

memories, experiences, free associations,

well they develop that theme. In What

absurdities and improvisations. The char¬

Dreams May Come, a piece inspired by

acters split, double, multiply, evaporate,

the book Nightmares by neuropsycholo¬

condense, dissolve and merge. But one

gist Patrick McNamara (2008), a company

consciousness rules them all: the dream¬

of 10 university acting students were asked

er’s; for him there are no secrets, no incon¬

to do dream journaling over the course of

sistencies, no scruples and no laws.”

several weeks and were then taken through

The dreamlike weaving together of dis¬

a series of exercises designed to capture

parate images that Strindberg mentions can

nightmare images, narrative sequences,

be a source of inspiration to the performer

and dialogue generated by their own sub¬

working to build authentic character and

conscious minds on the theme “Face Your

narrative. Theater artists know that, like

Fears.” Young actors usually respond im¬

dreams, the best dramatic creations affect

mediately to the idea of dream enactment

the viewer on many levels, as much intui¬

because it gives them license to explore

tively as consciously. And using strong im¬

and to play. In this case, scores of dream

ages mined from one’s own subconscious

fragments were written down, recorded,




Stages of Sleep and Associated Waveforms

or worked out in movement. Many of these, however, were ultimately rejected as being either too obscure or too obvious. The weaving together of the remaining ele¬ ments with video, sound, and group move¬ ment resulted in sequences that brought to coherent life on stage the universal and

McNamara, P. (2008). Nightmares: The sci¬ ence and solution of those frightening vi¬ sions during sleep. Westport, CT: Praeger

Perspectives. Priestley, J.B. (1937). Time and the Conways. New York: Harper Brothers. Strindberg, A. (1919). A dream play. University of California Press.

often enigmatic qualities of nightmares and powerfully illustrated the theme. There are other examples too numer¬

Stages of Sleep and Associated Waveforms

ous to mention here, but before closing I can suggest an area of potential study that

We are living in a rhythmic environment.

might combine scientific and performance

Temperature and daylight vary with the

research. Brain-imaging techniques such as

seasons and with it vegetation and nature

functional magnetic resonance imaging have

changes, as does the behavior of animals,

advanced in recent years to allow research¬

humans, yet all living organisms. In short,

ers to see emotional responses in the brain.

to be successful in the course of evolution

Perhaps it will be possible in the future to

and everyday-life behavior of any crea¬

observe more closely a dreamer’s emotional

ture must oscillate with the cadences of its

responses during sleep and to compare them

environment. The most striking and obvi¬

with the subject’s memories of the dream.

ous periodic behavior is the alternation be¬

The conjunctions and disjunctions in these

tween waking and sleeping behavior. The

two narratives could be put into theatrical

electrical rhythms generated by the massed

form to explore the relation of truth and fic¬

firing of neuronal tissue in the brain char¬

tion or the idea of multiple realities.

acterize these two distinct states and are

Given the variety of the treatment of

recorded by EEG, first described in 1929

dreams in the history of theater, it is safe

by the Austrian psychiatrist Hans Berger.

to say that we have not yet exhausted the

In general, high-frequency, low-amplitude

fruitfulness of studying the interrelation of

rhythms are associated with alertness and

these two modes of self-knowledge.

waking or the dreaming stages of sleep.

Robert Shampain

Low-frequency, high-amplitude oscilla¬ tions on the other hand are associated with


nondreaming sleep stages and with the

Almansi, G., & Beguin, C. (2009). Theatre of sleep (online Creative Commons Copyright). Retrieved from http://www. archive.org/stream/TheatreOfSleep/theatre_ of_sleep_01.txt

pathological state of coma.

Dunne, J.W. (1927). An experiment with time. London: Faber & Faber.

is not logical and can only be understood in

Lipsky, J. (2009). Dreaming together. Burdett, NY: Larson Publications.

tentials recorded from the scalp of normal

The rhythms are categorized by their frequency range each named after a Greek letter. The sequence of these Greek letters historical terms. The frequencies of the po¬ humans typically vary from 0.5 to 50 Hz,

Stages of Sleep and Associated Waveforms


and the amplitudes typically lie between 10

is normally not prevalent in the awake

and 50 pV.

adult, but is a prominent feature of sleep

Since even the earliest empirical find¬

and becomes increasingly dominant dur¬

ings in EEG research the alpha (a) rhythm

ing the progress from light to deep stages.

(8-13 Hz) has presented itself as the most

Delta waves have the largest amplitudes,

dominant brain oscillations in the human

normally between 20 and 200 pV. Electro-

EEG. The a-rhythm does tend to increase

encephalographic activity between 4 and

in amplitude during rest and relaxation

7 Hz or theta (0) activity is seen in normal

and is relatively absent during intellec¬

drowsiness and sleep, and during wakeful¬

tual functioning (for review see Klimesch,

ness in young children. Theta is also pres¬

1999). Thus, a strong a-rhythm can gen¬

ent in normal waking adults and has been

erally be observed in relaxed individu¬

related to the encoding of new information

als who are awake with their eyes closed.

(cf. Klimesch, 1999).

Sensory stimulation or strain during the re¬ cording usually causes significant reduc¬ tion of the a-rhythm and replacement with lower voltage, faster frequencies. The find¬ ing that alpha desynchronizes or becomes suppressed during mental activity was al¬ ready described in the late 1920s by Berger (1929). Alpha often has a mean frequency cen¬ tering around 10 Hz with the maximum voltage over the parieto-occipital elec¬ trodes. However, evidence provided by Klimesch (1999) indicates that within the 8- to 13-Hz alpha range, different fre¬ quency bands should be differenced; lower alpha (6-10 Hz) reflecting attentional pro¬ cesses and upper alpha (10-12 Hz) reflect¬ ing the processing of sensory-semantic information. The a-rhythm is thought to be generated in thalamo-cortical feedback loops as discussed in detail by Lopes da Silva (1999). Beta (P) waves (>14 Hz) occur in all in¬ dividuals, are usually of low amplitude, and are normally distributed maximally over frontal and central regions. Gener¬

Stages of Sleep According to the new sleep classification from the American Academy of Sleep Medicine (AASM) (Iber, Ancoli-Israel, Chesson, & Quan, 2007) waking (W) is associated with trains of sinusoidal 8 to 13 Hz activity (predominantly over occip¬ ital brain areas). Light sleep (Nl) is asso¬ ciated with low amplitude, predominantly 4 to 7 Hz activity and sharply contoured vertex waves (with duration 0.5 seconds in du¬ ration) and sleep spindles (12-15 Hz wax¬ ing and waning oscillatory bursts). Last but not least, rapid eye movement sleep (R) is reflected by low-amplitude, mixedfrequency EEG, sawtooth waves (trains of sharply contoured 2-6 Hz waves), low chin EMG, and rapid eye movements in the electrooculogram. Manuel Schabus

ally spoken, beta rhythms signal an acti¬ vated cortex. Delta () activity (0.5-4 Hz)

See also: entries related to Sleep Assessment




Structural Analysis

Dream Narratives


similar temporal-linear, organized, struc¬

Berger, H. (1929). Uber das Elektroenkephalogramm des Menschen. Archives Psychiatriaca Nervenkraus, 87, 527-570.

tural schema to that of narratives of every¬

Iber, C., Ancoli-Israel, S., Chesson, A., & Quan, S.F. (2007). The AASM manual for

is based on five narrative units, includ¬

the scoring of sleep and associated events: Rules terminology and technical specifica¬ tions. Westchester, IL: American Academy

of Sleep Medicine. Klimesch, W. (1999). EEG alpha and theta oscillations reflect cognitive and memory performance: A review and analysis. Brain Research Reviews, 29, 169-195.

day personal events (Cariola, 2008). The temporal sequence of dream narratives ing (1) topic introduction, (2) orientation, (3) complication, (4) evaluation, and (5) coda. The topic introduction unit represents a conversation turn sequence in which the topic of dreams may be introduced through sharing one’s own dream memory in a so¬ cial situation or in the form of a question

Lopes da Silva, F.H. (1999). Dynamics of EEGs as signals of neuronal populations: Models and theoretical considerations. In E. Niedermeyer & F. Lopes da Silva (Eds.),

The topic introduction is also often reintro¬

Electroencephalography: Basic principles,

duced at the beginning of the orientation

clinical applications,

and related fields

unit; for example, in my dream. Orienta¬

(pp. 149-173). Baltimore, MD: Williams & Wilkins.

tion units can be differentiated between

directed at the conversational partner; for example, “What did you dream last night?”

real-life orientations and dream content orientations. Real-life orientations assume

Structural Analysis of Dream Narratives

a causal and temporal boundary function with the narrator typically disclosing a per¬ sonal event that is associated as a possible

A structural and functional approach to

trigger for the dream event; for example,

the analysis of everyday personal narra¬

“One day I think. . .it leads from. . .1 let

tives was first proposed by Labov and

my dog out in the garden once when she

Waletzky (1967). They defined narratives

was younger. She was a rescue dog and I

as “one method of recapitulating past ex¬

had to have a lot of control over her be¬

perience by matching a verbal sequence of

cause she was very scared of people and

clauses to the sequence of events that actu¬

she’d bite them.” Real-life orientations

ally occurred” (Labov & Waletzky, 1967,

also represent a bridge between an actual

p. 20). They also suggested that narratives

self-awareness of a waking conscious state

follow a distinctive sequencing schema,

and a self-awareness of a narrative con¬

resulting in a fixed temporal order of six

scious state. Dream content orientations

narrative units: (1) abstract, (2) orientation,

introduce the dream event in the form of

(3) complication, (4) evaluation, (5) reso¬

spatial contextual information, thus creat¬

lution, and (6) coda.

ing a virtual spatiotemporal frame in which

Dream narratives are a type of per¬

the actions of the characters are situated;

sonal narrative, and it has been shown

for example, “But that same night when I

that orally elicited dream recall follows a

went to sleep I had a dream about me and

Structural Analysis of Dream Narratives


my dog... uh.. .taking my dog to an island

unit, whereas positive dreams may or may

very strange on a boat.”

not imply a conflict, arousing positive emo¬

The complication unit communicates the

tions and therefore not calling for a resolu¬

actions and encountered problems of the vir¬

tion unit” (Cariola, 2008, p. 17). Habermas,

tual protagonist. It can also be differentiated

Meier, and Mukhtar (2009) have, however,

between simple and developing complica¬

identified linguistic and structural differ¬

tions. Simple complications draw on a soli¬

ences in adults’ and children’s emotionally

tary complication event; for example, “I was

positive and negative personal narratives;

at my parents’ house and my teeth started

for example, fear narratives reflected the

crumbling. And then they just stalled falling

lowest frequency of complication units as

out and crumbling. Then I remember look¬

compared with other types of negative nar¬

ing into the mirror and trying to smile and

ratives, whereas happy and sad narratives

seeing lots of gaps,” whereas a developing

reflected a sudden closing sequence in the

complication conveys a complication that

form of a complication unit without the use

develops throughout the narrative in the¬

of a following successive resolution unit.

matically and causally linked event.

Consequently, future research might in¬

The complication unit is followed by the

vestigate qualitatively and quantitatively

evaluation unit that conveys, implicitly or

the structural and functional framework of

explicitly, the narrator’s personal attitude,

pleasant dreams and nightmares and thus

feelings, and phenomenological point of

establish a comprehensive linguistic and

view about the dream event; for example,

structural model of dream narratives.

“It was a bit weird.” The evaluation unit

Laura Annamaria Cariola

may also function as a preclosing sequence that coincides with the coda unit; for ex¬

See also: entries related to Dream Content

ample, “That is sort of the dream I can only remember. It seems quite short although in your mind you.. .it felt for ages. But that’s pretty much the dream I had.” The coda unit represents the closing se¬ quence of the narrative, most typically in the form of a closing statement of the mo¬ ment of awakening “and then I woke up” or the recall of the dream; for example, “I cannot remember anything more.” The coda unit may also coincide with the reso¬ lution unit (Labov, 1997). Empirical research has not yet assessed the structural and functional framework of pleasant dreams and nightmares, for which “nightmares laden with tension and con¬ flicts may or may not propose a resolution

References Cariola, L.A. (2008). A structural and func¬ tional analysis of dream narratives. Dream¬ ing, 18, 16-26. Habermas, T., Meier, M., & Mukhtar, B. (2009). Are specific emotions narrated dif¬ ferently? Emotion, 9, 751-762. Labov, W. (1997). Some further steps in narra¬ tive analysis. Journal of Narrative and Life History, 7, 395—415. Labov, W., & Waletzky, J. (1967). Narrative analysis: Oral versions of personal experi¬ ence: Essays on the verbal and visual arts. In June Helm (Ed.), American Ethnological Society (pp. 12-44). Seattle: University of Washington Press. Toolan, M. (2005). Narrative: A critical lin¬ guistic introduction. New York: Routledge.




Subjective Experience across States of Sleep and Wakefulness

Subjective Experience across States of Sleep and Wakefulness

experiences often occur outside of REM

Historically, dreaming has been viewed

rates of dream recall (with participants re¬

as a state of consciousness largely dispa¬

calling dreaming about 80% of the time

rate from that of waking cognition. Due

when awakened from REM sleep), and

to their apparently bizarre nature, dreams

dreams during REM tend to be particularly

were once ascribed to external origins, as

complex and emotional. However, dream¬

supernatural omens or messages from the

ing is reported approximately 50 percent

gods. In the early 1900s, Freud translated

of the time from non-REM sleep as well,

this otherworldly view of dreams as mes¬

and cognition during these sleep stages can

sages into psychological terms, populariz¬

at times be as bizarre, vivid, and story-like

ing the notion that dreams originate from

as REM dreaming, particularly late in the

repressed wishes in an unconscious por¬

night. These observations suggest that the

tion of the mind that is inaccessible to our

generation of hallucinatory imagery and

waking thoughts. As this specific view of

thought during sleep in general must be ex¬

dreaming fell out of favor, more modern

plained by mechanisms that are common to

neuroscience-based approaches continued

all stages of sleep.

(Foulkes, 1967), including during the deep¬ est stages of slow-wave sleep. The REM state is consistently associated with high

to emphasize dreaming as a neurophysio¬

In fact, recent evidence suggests that

logical state best viewed as distinct from

dreaming is best viewed as a part of a con¬

all other forms of cognition. Following the

tinuum of spontaneously generated cogni¬

first all-night electrophysiological stud¬

tion that occurs in all states of sleep, and

ies of the sleeping brain in the 1950s, the

which shares meaningful features with

discovery of rapid eye movement sleep

waking thought and imagery during peri¬

(REM) provided an attractive candidate

ods of rest, when attention to sensory input

for a brain-state correlate of dream experi¬

is reduced. Research on the default mode of

ence. At the time, dreams were thought to

cognition during resting wakefulness has

be confined exclusively to REM sleep (De¬

been particularly helpful in understand¬

ment & Kleitman, 1957). The activation-

ing the neural basis of daydreaming (An-

synthesis hypothesis of Hobson and Mc-

drews-Hanna, Reidler, Huang, & Buckner,

Carley (1977) built on this notion of REM

2010), and how the study of waking cog¬

as the neural substrate for dreaming, link¬

nition may inform our understanding of

ing proposed features of dreaming (such

sleep and dreaming states (Wamsley &

as bizarreness, intense emotionality, and

Stickgold, 2010). The term default net¬

hallucination) to the elevated acetylcho¬

work refers to a collection of brain regions

line levels, brain stem activity, and de¬

that are particularly active during resting



wakefulness (including medial temporal,

the REM state. However, subsequent re¬

medial prefrontal, midline, and parietal

search revealed that to the contrary, dream

regions). This rest-activity network has



Subjective Experience across States of Sleep and Wakefulness


been linked to the processing of memory,

understand dreaming, we must first under¬

theory of mind, and preparation for fu¬

stand the general mechanisms that produce

ture experience, reminding the neurosci¬

spontaneous mental imagery in any state

ence community that in rest, as in sleep,

of consciousness. To date, a strong focus

the brain continues to process information

on interstate variations in cognition may

and to generate conscious experience. This

have hindered progress in understanding

network pattern during quiet wakefulness

these more basic neural correlates of off¬

may provide a partial explanation for the

line cognition. Following recent work on

construction of daydreaming, with one re¬

the default mode of brain function, future

cent study reporting that individuals who

research could profitably explore neural

experience more daydream-like thoughts

mechanisms of off-line cognition common

of the past and future during a resting con¬

to REM sleep, NREM sleep, and wake¬

dition exhibit increased functional connec¬

fulness. In particular, the engagement of

tivity between components of the default

memory systems during quiet resting and

network (Andrews-Hanna et al., 2010).

during sleep states, both of which are asso¬

Thus, this activity pattern appears to sup¬

ciated with the reactivation of recent mem¬

port the generation of spontaneous thought

ory traces, suggests a common function

and imagery during wakefulness. Tell¬

for dream experience and waking cogni¬

ingly, similar patterns of brain activity are

tion in the processing of new memories

present throughout sleep, as medial tempo¬

(Wamsley & Stickgold, 2010). Erin J. Wamsley

ral and midline frontal regions remain rela¬ tively active during both REM and NREM

See also: Sleep and Mild Cognitive Impairment

stages. As sleep and default-mode cogni¬ tion also share electrophysiological and


neurochemical features thought to sup¬

Andrews-Hanna, J.R., Reidler, J.S., Huang, C., & Buckner, R.L. (2010). Evidence for the default network’s role in spontaneous cognition. Journal of Neurophysiology, 104(1), 322-335.

port the generation of mental imagery, this thriving line of research in the cognitive neurosciences provides a promising win¬ dow into mechanisms that may support dream experience. Certainly, there are meaningful distinc¬ tions to be made between various states of sleep and wakefulness in terms of the form that subjective experience takes. That dreaming is more prevalent and more emotional in REM than in NREM sleep, for example, may yet prove to be instruc¬ tive in linking particular qualities of dream experience to patterns of neural activity in the REM state. Yet at the same time, to

Dement, W., & Kleitman, N. (1957). The re¬ lation of eye movements during sleep to dream activity: An objective method for the study of dreaming. Journal of Experimental Psychology, 55(5), 339-346. Foulkes, D. (1967). Nonrapid eye movement mentation. Experimental Neurology (Suppl. 4), 28-38. Hobson, J. A., & McCarley, R. W. (1977). The brain as a dream state generator: An acti¬ vation-synthesis hypothesis of the dream process. American Journal of Psychiatry, 134(12), 1335-1348.




Sumerian Dream Beliefs

Wamsley, E. J„ & Stickgold, R. (2010). Dream¬ ing and offline memory processing. Current Biology, 20(23), R1010-R1013.

very limited in Sumer; only a special class of scribes drawn mostly from the upper classes received training in the difficult cuneiform script. In later times, a special class of specialist priests and priestesses

Sumerian Dream Beliefs

called shailu, or questioners, were called on to interpret dreams by asking specific

Sumerian civilization was the first to de¬

questions of the dreamer from long lists of

velop writing and the first from which lit¬

dream symbols and their correspondences

erary texts remain, dating back to the late

provided on archival tablets. The corre¬

third millennium BCE. Some of these texts

spondences included many mechanisms

contain accounts of dreams, especially of

for dream insight on which we still rely

royal figures. The Sumerians made a dis¬

today: analogy, punning references, free

tinction between clear dreams, which come

association, and inversion. Their goal was

only to people who have observed the

to solve the dream, image by image, almost

proper ritual preparations, and obscure or

as if it were a cryptic equation with but a

symbolic dreams, which come to everyone

single solution, and Noegel (2001, p. 53)

else and require professional interpreta¬

comments that “in this sense dream inter¬

tion. A ruler who wished to obtain guidance

pretation in Mesopotamia represents less a

from dreams would go to a special incuba¬

preoccupation with ambiguity than an at¬

tion hut made of reeds to sleep. The walls

tempt at rendering ambiguity into a pro¬

of the hut were permeable, so as to receive

jected and authoritative reality.”

dream messages from the gods. The earli¬

The earliest of the Sumerian dream texts,

est Sumerian flood hero, Ziusudra, enters

and evidently the earliest recorded dream

such a reed hut for incubation. Ziusudra is

in history, is the dream of Dumuzi of Elruk.

a model of piety: “humbly obedient, rev¬

Not only is the dream text itself included

erent, attending daily, constantly, bringing

but also its interpretation, by Dumuzi’s sis¬

forth all kinds of dreams, uttering the name

ter Geshtin-anna. Her role as a professional

of heaven and earth” (Kramer, 1958, p. 29).

dream interpreter indicates that as early as

His reward is a dream from his god, Enki,

the middle of the third millennium BCE

warning him of the coming flood. Similarly,

dreams—especially those of monarchs—

in the Epic of Gilgamesh, the bull-man En-

were taken seriously and acted on. She in¬

kidu has a pair of dreams that clearly fore¬

terprets the symbols in Dumuzi’s dream,

tell his death, and no further interpretation

on a one-for-one basis, as representing a

is necessary (Speiser, 1958, pp. 58-59).

danger to her brother, and urges him to

The second type of dream is described

flee. Bendt Alster (1972, p. 43), who pub¬

in a text as “a closed archive basket of the

lished the first critical edition of this text,

gods” (Noegel, 2001, p. 47). This links the

has provided ample evidence that the text

idea of interpretation with the act of read¬

of Dumuzi’s dream has a formulaic quality

ing a cuneiform tablet, as archival docu¬

that derives from poetic rather than oneirocritic demands.

ments were stored in baskets. Literacy was

Survivors of the Holocaust and Rwandan Genocide: Dream Accounts

Such one-for-one interpretations are common in later dream-interpretation texts. In the Babylonian Epic ofGilgamesh, there is another example of dream interpretation by a female figure. Gilgamesh, the young king of Uruk, has angered the elders of the town. They complain to the gods, who create Enkidu, a wild man who combines human and bull characteristics. As Enkidu


pp. 28-30). Princeton, NJ: Princeton Uni¬ versity Press. Kramer, S.N. (1963). The Sumerians: Their history, culture, and character. Chicago: University of Chicago Press. Noegel, S. (2001). Dreams and dream inter¬ preters in Mesopotamia and in the Hebrew bible (Old Testament). In K. Bulkeley (Ed.), Dreams (pp. 45-72). New York: Palgrave.

approaches Uruk, Gilgamesh has two sig¬

Speiser, E. A. (1958). Akkadian myths and epics. In J.B. Pritchard (Ed.), The ancient

nificant dreams that he brings to his mother,

Near East: An anthology of texts and pic¬

the goddess Nin-sun, Lady Wild-Cow, for

tures (Vol. 1, pp. 31-86). Princeton, NJ:

interpretation. She interprets the symbols

Princeton University Press.

of the dream on a one-for-one basis, indi¬ cating the coming of a companion (Speiser, 1958, p. 46). Similarly when the historical gover¬ nor of the city of Lagash, Gudea, was

Survivors of the Holocaust and Rwandan Genocide: Dream Accounts

perplexed by a dream, he brought it to a priestess of the goddess Nanshe, a daugh¬

Trauma experienced by genocide survi¬

ter of Enki. Speaking as the goddess, the

vors is extreme to a level almost beyond

priestess interpreted the dream, using the

comprehension. Many survivors witnessed

same image-for-image method, indicating

the brutal murders of family and friends.

that Gudea should build a temple to his god

Often their communities have been de¬

Ningishzida, the consort of Geshtin-anna

stroyed, and many have suffered physi¬

(Kramer, 1963, p. 138). Gudea’s statues

cally from their ordeals. They are left with

commemorate both the dream and the re¬

the feeling that the world failed them. Life

sulting construction project.

for them will never again be the same.

Curtiss R. Hoffman

The dreams of genocide survivors provide a glimpse into significant posttraumatic

See also: entries related to History of Dreams/

stress disorder. These dreams frequently


include seeing or receiving messages from deceased family members or reliving the

References Alster, B. (1972). Dumuzi’s dream: Aspects of oral poetry in a Sumerian myth. In Meso¬ potamia: Copenhagen studies in Assyriology, 1. Copenhagen, Denmark: Akademisk

Forlag. Kramer, S. N..5,(1958). A Sumerian myth. In J. B. Pritchard (Ed.), The ancient Near East: An anthology of texts and pictures (Vol. 1,

horror through nightmares. During the Holocaust, dreams of food were quite common. As prisoners were given barely enough food to survive, their bodies diseased and emaciated, food often became the main theme of their dreams. While some might consider these to be wish-fulfillment dreams, perhaps another




Survivors of the Holocaust and Rwandan Genocide: Dream Accounts

purpose of these dreams was the mind’s

brothers were also killed, leaving him as

final attempt to fool the body a short while

the only surviving member of his family.

longer as a means of survival. Some Ho¬

He survived alone in the wilderness for 103

locaust survivors described dreams that

days at the age of 10 before being found

helped them to survive. In one example, a

by Rwandan Patriotic Front soldiers. He

survivor heard his deceased father telling

told of one of his post-genocide dreams in

him to run. He awoke from his dream and

which he was standing in the halls of the

escaped from the concentration camp with

United Nations, pleading for someone to

other boys after the watchman had fallen

listen and come save his people. No one

asleep, thereby avoiding the gas chamber.

would listen. His dream was quite literal in

Another man who had decided to commit

his desire to share his story with the world.

suicide dreamed of his mother telling him

One of the themes of some dreams of geno¬

that he must live because there was no one

cide survivors is their desire to try and tell

else left in the family to tell their story.

the world, or to make the world a better

In the years following the Holocaust,


guilt became a common theme among

Many people who were not targeted in

survivors. In order to avoid death in the

genocides, but who were witnesses in some

camps, one often had to choose his or her

regard, also experience nightmares. A re¬

own best interests over that of fellow pris¬

porter during the genocide in Rwanda has

oners. Stealing bread or taking someone

since spoken of dreams of corpses and road

else’s shoes was often a necessity to avoid

blocks, which go along with his feelings

death, the cost of which was looking back

of failure to be able to help the people at

years later with painful regret. After lib¬

the time. Similar dreams have been experi¬

eration, the minds of survivors were free

enced by people who were not targeted by

to begin contemplating the events they had

the Nazis during the Holocaust. Fear pre¬

lived through and all that they had lost.

vented people from intervention, and that

Nightmares of being back in the camps

fear combined with guilt manifested itself

were very common among survivors in

in the dreams of these people.

the years and decades following liberation.

The magnitude of genocide is such that

The 1994 genocide against Tutsi in

the effects of it are multigenerational. It

Rwanda was much different than the Ho¬

may take several more years to understand

locaust as the killings took place over a pe¬

the extent of this fact with the Rwandan

riod of only about 100 days. Survivors did

genocide as most of the survivors are still

not live in concentration camps for weeks

young adults. The Holocaust provides

or months on end as they did in the Holo¬

more historical evidence of the effects of

caust. However, most of them personally

it on second-generation and even third-

witnessed the gruesome deaths of their

generation survivors. The children of Ho¬

families. Jean Nepomuscene Sibomana

locaust survivors grew up often knowing

lost his family in the genocide. He watched

little about their parents’ ordeals and fam¬

as his mother and sister were hacked to

ily history, leaving many with unanswered

death with machetes. His father and three






also dealt with feelings of shame over their

such that a person might see pain or taste a

parents’ lack of social and language skills

sound. Intrigued by the not possible nature

in their adopted countries. Dream reports

of it, also characteristic of many dreams,

from second-generation survivors often

an independent dream researcher collected

include Nazis, swastikas, cattle cars, and

reports of synesthetes’ dreams and dream¬

other symbols commonly associated with

ers’ experiences of synesthesia. She sug¬

the Holocaust.

gests the two fields of study might have David L. Kahn

insights to offer each other, particularly about metaphor and psi.

References Frankl, V.E. (1984). Man's search for mean¬ ing: An introduction to logotherapy (3rd ed.). New York: Simon & Schuster. Ilani, O. (2008, January 5). What did con¬ centration camp inmates dream about?

Retrieved from http://www.haaretz.com/ hasen/spages/97981 l.html Ilani, O. (2008, May 2). My mother came to

In synesthesia, when a person perceives a stimulus, another specific sensation oc¬ curs at the same time. The musical note B might come with a taste like almonds. Or temperature may come with sound. Or pain with color. Or (in the standard notation for connecting an inducer with its synesthetic correlate), emotion -A smell.

tell me I had to remain among the living.

At least 63 such combinations have

Retrieved from http://www.haaretz.com/ hasen/spages/979526.html

been observed (Day, 2010). Color is by

Ilibagiza, I. (2007). Left to tell: Discovering God amidst the Rwandan Holocaust. New York: Hay House.

mates of synesthesia’s prevalence vary

Papirblat, S. (2006, April 25). Holocaust ef¬ fects: Son of Holocaust survivor still car¬ ries scars; will next generation be different?

Retrieved from ynetnews.com

far the most common correlate. Esti¬ widely, but some researchers speculate that basic forms of syn, too, might be universal. Some forms are intramodal (e.g., a vi¬ sual inducer linked with a visual correlate),

Rusesabagina, P., & Zoellner, T. (2006). An ordinary man. New York: Penguin Group.

some are intermodal or cross-dimensional

Sebarenzi, J. (2009). God sleeps in Rwanda. New York: Atria Books, a Division of Simon & Shuster.

touch —»taste), and some are conceptual—

Weiss, I., & Kosino, B. (1998). Czechoslova¬ kia, 1923. In A. Brostoff & S. Chamovitz (Eds.), Flares of memory: Stories of child¬ hood during the Holocaust (pp. 198-224). New York: Oxford University Press.

(two different sensory channels, such as one of the most common being a sense that days of the week or months of the year are arrayed spatially around the person. Com¬ binations can be more complex, such as [pain -a color, motion, location], and many synesthetes have more than one type. All combinations are one-way streets from in¬ ducer to correlate.


Synesthesia is instantaneous, an insepa¬ rable part of the experiencer’s reality, al¬

Synesthesia is a neurological blending

though it can fade if a person stops paying

of sensory experiences in unusual ways.

attention to it. Most synesthesia has its





such as those of Des Hegarty. In a post to The Synesthesia List (May 18,2004), a pri¬ vate e-mail community, he said, “As I relax in meditation or about to drop into sleep, if I am disturbed by a noise, it stimulates my visual senses and produces a short burst of what could best be described as TV snow.” At the other end are the long, elabo¬ rate experiences of the late Shawn Allen O’Neal, an artist, musician, and sound de¬ signer. His synesthesia was strongest in the hypnogogic state and did not require an ex¬ ternal stimulus (personal communication, June 8, 2003): A typical specific instance might in¬ volve a self-generating saxophone solo, In Zig Zag, Carol Steen has realistically depicted

which appears as a silvery, mercurial,

her synesthetic experience of color and form

highly reflective, morphing and vibrat¬

constants that coupled with the sensations of an

ing orb which may leave an intermittent

acupuncture session, she writes. “I watched the

“trail” of its various forms as it (and I

visions come once all the needles were in place. I

with it) accelerates, swooping and zoom¬

saw swirling greens, and this amazing zig zag ... What I paint is realistic. It’s considered abstract by those who cannot see what I see, and ac¬ curate in feeling and gesture by those who [have similar synesthetic correlates].” (Carol Steen)

ing forward in space. “Chords” of neon “worms” may chase and writhe around this form. “Beneath” this might be a rhythm section of percussion, marimbas, basses, etc., where each note “appears” in space as part of a “geodesic series” or fabric of spinning, multi-colored tri¬

origins in early childhood, but it can also

angular panels, flocking, re-arranging

result from brain injury, the use of halluci¬

and bursting forward like a scintillating

nogenic drugs, or epileptic seizure. Studies have established that syn is not just vivid imagination or learned associations. Brain imaging shows perception activates more

reptilian skin, the faceted note-shapes with the most emphasis always glinting perfectly with the most light. (And yes, this is all without the aid of psychedelic drugs.)

areas in synesthetes than nonsynesthetes, and psychological tests find that individ¬

Experiences can differ between waking

ual synesthetes’ responses to a stimulus are

and dreaming. For O’Neal (who went by

consistent over long periods, unlike those

his initials, Sao, in some online forums),

of nonsynesthetes.

the synesthesia so abundant as he fell

Yet syn experiences are highly individu¬

asleep nearly disappeared in his dreams.

alistic. Responses can be brief and simple,

On a few occasions, the syn in author Pat



Duffy ’ s (2001) dreams has been of a differ¬

music professor. In it, the motion of trees

ent type than the grapheme -» color corre¬

is music:

spondences in her waking life. In a Biology 202 paper online, Bryn Mawr College stu¬

The trees were all blowing. The wind was blowing, and some were blowing

dent Sadie White (2002), a nonsynesthete, wrote:

that way and some were blowing this

I was staring, entranced, at a delicate

. . . Then gradually they all started to

white flower. It was like nothing I had

line up toward this climax, and I real¬

way. And it was a counterpoint of trees

seen or experienced in my waking life,

ized then in that dream how to write a

because the pristine, thinly-veined petals

climax in music. . . .

were such an exquisite color that it mani¬ fested itself upon my dreaming brain as a color and a sound. The white song was

Unlike the musical compositions and other expressions it may inspire, though,

a single note—like a distant choir lifting

synesthesia does not generate integrated

its voice in concerted wonder.

perceptions. In that sense, it is also unlike

Wide-ranging individuality is something synesthesia and dreams have in common. So is the strong sense that the experience is real; is full of nuance and often difficult to describe; and has strong emotional in¬ volvement. (“Synesthetes often gush over trivial tasks such as remembering a name or phone number, calling it ‘gorgeous’ or ‘delightful,’ whereas mismatched per¬ ceptions—such as seeing a letter printed in the wrong color ink—can be like fin¬ gernails on a blackboard,” say neurolo¬ gist Richard Cytowic and neuroscientist David Eagleman [2009, p. 54].) For these reasons, perhaps, both dreams and syn are sources of creative material for much artis¬

dreams, many of which are full of distinct characters, landscapes, and objects (all considered to be imagery) and extensive narratives. Instead, syn generates generic tastes, sounds, and shapes—blobs, trian¬ gles, lines, spirals, and other geometric form constants.

Yet there is some overlap here with dream studies. In the hypnopompic state between dreaming and awakening, George Gillespie (1997) observes lattices. Ed Kel¬ logg (1999) perceives basic forms in lucid dreams when he resists the human ten¬ dency to identify things. Dale Graff (2004) has found form constants to be integral to dreams:

tic expression (e.g., by synesthetes Vladi¬

In the mid-1970s, I began incubating

mir Nabokov, Wassily Kandinsky, David

dreams that hopefully would reveal

Hockney, and Alexander Scriabin), or sim¬ ply interesting enough to inspire great ef¬ forts at precise expression.

something basic about the nature of dream imagery and how [dreams] were constructed.

The creativity of syn and dreams over¬

In time, the dreams presented only hon¬

lapped in a life-guiding way for G. Roger

eycombs, grids, lines (vertical, angled,

Davis. A dream recounted in the jour¬

horizontal), spirals and whirling white area

nal Dreaming (Knudson, 2001) inspired

globs! . . .At. . . times the dynamic forms

Davis in his career as a composer and

merge to create recognizable shapes, as if





a subconscious process was occurring that

missing, and that synesthesia involves un¬

selected, fragment by fragment, what was

usual feedback or feed-forward along the

required to build up the image.

brain’s nerve pathways. As a group, syn

Graff is a physicist and former director

investigators acknowledge that their re¬

of the federal government’s remote view¬

search has focused almost exclusively on

ing research, Project Stargate. He says


remote viewing perceptions, too, come

the grapheme —» color type, and that their

through as form constants.

theories cannot yet account for learning

Cytowic and Eagleman (2009) have



(of, e.g., the days of the week).

noted that unusual experiences such as deja

Given the importance of metaphor to

vu, clairvoyance, and a sense of porten¬

dream interpretation, one of the most in¬

tousness seem somewhat common among

triguing ideas about synesthesia is that it

synesthetes, and at least seven synesthetes

has played a role in binding meanings as

among the small sample Sturzenacker con¬

well—that it, is the source of metaphor,

tacted reported psi experiences—several

and from that, language. Eric Odgaard and

of them attesting they have them often.

Lawrence Marks (2004) say it is important

If researchers can discover how percep¬

to distinguish between the vivid concur¬

tions are tied together in synesthesia, they

rents of strong synesthesia, which is rare,

will have contributed to solving the larger

and the everyday weak synesthesia that

binding problem. Very small regions of the

they liken to metaphor. A 1929 experiment

brain specialize in analyzing different as¬

asked people to match each of two made-

pects of an object or scene, from the shape

up words, bouba and kiki, with one of two

of a pen to its color to its orientation to how

pictures. Across cultures, they overwhelm¬

light changes at its edges. The question is

ingly matched the first to an amoeba-like

how the brain puts all that data together

shape and the second to a jagged, pointy

into an integrated perception so a person

one. Cytowic and Eagleman (2009) extend

can accurately reach for the pen and pick it

the case that metaphor arises from physi¬

up without a moment’s hesitation.

cal experience rather than being derived

Several theories exist (Ramachandran &

from abstract language. They propose a

Hubbard, 2003). From prenatal develop¬

cognitive continuum: perceptual similari¬

ment into early childhood, humans have

ties —» synesthetic equivalences —> meta¬

an overabundance of connections among

phoric identities —> abstract language.

various brain regions. Around age three,

Shawn O’Neal (2003) posted this de¬

the number becomes drastically reduced,

scription of what happens once he tunes

or pruned. A dominant theory is that syn¬

into the flow of synesthetic sensations in

esthesia is a greater-than-usual cross-ac¬

the hypnogogic state. Could it be an actual

tivation of different regions that results

experience of moving along the continuum

from an absence or inadequacy of prun¬

from synesthesia to metaphor?

ing. A variation is that neurotransmitters

I am able to look back and see that not

do the cross-activating. Another theory is

only have larger patterns been created by

that some inhibitory mechanism might be

whatever I am watching and listening to


close up—but these larger patterns con¬ tinue to evolve, or branch off and recon¬ nect, so that the whole composition may fill enormous panoramic volumes of space, sometimes creating landscapes or archi¬ tecture and sometimes simply accelerating nonobjectively into a void. Complete, co¬ herent scenes may form and break up again in perfect synchronicity to the sounds, and often these scenes will suddenly, momen¬ tarily, poignantly reflect the sort of actual, natural scenes one might be reminded of by ordinary listening (such as “this reminds me of being on the ocean” or “in a valley of aspen trees at twilight” or “in a particular room”). Here too, the lapse of being aware that I am reminded of something and per¬ ceiving the manifestation of the thing I am reminded of is startlingly instantaneous. What might researchers in the two fields, dreaming and synesthesia, be able to learn from focusing closely on how the abun¬ dant, mostly visual metaphors observed in dreaming are created? Gloria Sturzenacker

References Cytowic, R.E., & Eagleman, D. M. (2009). Wednesday is indigo blue: Discovering the brain of synesthesia. Cambridge, MA: The MIT Press.


Day, S. (2010). Types of synesthesia. Synes¬ thesia. Retrieved from http://home.Comcast. net/~sean.day/html/types.html Duffy, P. L. (2001). Blue cats and chartreuse kittens: How synesthetes color their worlds. New York: Times Books. Gillespie, G. (1997). Hypnopompic imagery and visual dream experience. Dreaming, 7(3). Kellogg III, E.W. (1999, October 7-9). Lucid dreaming and the phenomeno¬ logical epoche. Presented at the Society for Phenomenology and the Human Sci¬ ences Conference, Eugene, Oregon. (Ab¬ stract available at http://dreamtalk.hy permart.net/2001 /abstracts/2001 _kellogg_ 01.htm) Knudson, R. (2001). Significant dreams: Bi¬ zarre or beautiful? Dreaming, 11(4). Odgaard, E.C., & Marks, L.E. (2004). Devel¬ opmental constraints on theories of synes¬ thesia. In L.C. Robertson & N. Sagiv (Eds.), Synesthesia: Perspectives from cognitive neuroscience. New York: Oxford Univer¬ sity Press. Ramachandran, V. S., & Hubbard, E. M. (2003, May). Hearing colors, tasting shapes. Scien¬ tific American, 288(5), 52-59. White, S. (2002). Synesthesia, report for Biology 202 course at Bryn Mawr Col¬ lege. Retrieved from http://serendip.bryn mawr.edu/bb/neuro/neuro01/webl/White. html


T Tarotpy Method

unconscious material and intuition to flow between client and therapist.

Pioneered during the early 1980s by Lau¬

While Tarotpy functions as a projec¬

ren Z. Schneider, MA, MFT, Tarotpy® is

tive tool for assessment and exploration,

an innovative approach to dreamwork and

a wealth of documented cases offers em¬

depth psychotherapy. Evolved over 25

pirical evidence of an unconscious mas¬

years, Tarotpy combines psychotherapeu¬

termind at play in the random selection

tic methods, dreamwork, hypnotherapy,

of cards and images. The process appears

family systems, semiotics, and Eye Move¬

more intentional than random in bringing

ment Desensitization and Reprocessing

information vital to emotional, physical,

(EMDR) with metaphysical tools.

and spiritual growth into consciousness.

Tarotpy uses the rich symbolic imagery of tarot, dream cards, and other image sys¬

First Case

tems to actively engage unconscious and intuitive processes. These archetypal im¬

Sue was a young 21 year old, struggling

ages arise from the same psychic pool as

to take her first steps toward financial

dreams. Tarotpy enhances dreamwork by

and emotional independence. After two

bringing further insight to a specific night

Tarotpy sessions, she shared a nightmare:

dream or stimulating imagination oth¬

“I’m in my room and there are ghosts. I

erwise blocked in some clients. Often, a

crawl terrified to my parents’ room. I have

Tarotpy session is followed by reports of

no voice to call out. I’m scared to enter,

more vivid dreaming.

but break through the fear and go in. They

As with dreamwork, the core principle

wonder what’s wrong with me. Finally I

of Tarotpy is profound respect for the in¬

cry out. There are ghosts in my room!’

herent wisdom, creativity, and wholeness

Then I’m holding a large cell phone with

of the psyche.

letters on the screen that spell ‘Tarotpy’.”

The client is instructed to select the

The phone image suggested that Tarotpy

deck, number of cards, formation, and

might offer further guidance into the

name of each placement, creating a lay¬

dream. I invited Sue to turn her attention

out. The client thus lays the unconscious

inward and ask her unconscious: “How

on the table, participating in a dreamlike

many cards do I need to see?” The num¬

consciousness with eyes wide open. Ap¬

ber four came immediately into her mind.

proached without preconceived ideas and

She selected a deck from the 30 plus decks

with a respectful desire to discover their

in my office and randomly chose four

intelligence, the images create a bridge for

cards, assigning each placement a special




Tarotpy Method





courage, and strength. Sue stared at the first card: The image

voice. The phrase letting go and the image of water dropping from a leaf prompted a visceral sense of peace and calmness.

of the dark-haired woman closely resem¬

Tarotpy opens a door beyond our per¬

bled Sue, and the ghostlike hands pulling

sonal, material, or rationalistic orientation

the woman’s hair matched the ghost image

and enters the realm of the dream where

in her dream.

events are not linear and causal, but rather

I asked about the card’s explicit label,

multilayered and simultaneous, where the

guilt; Sue said she felt guilty all the time.

ordinary and extraordinary merge. The

I reflected that children often take on the

meaningful connection between the card

guilt of their parents’ unresolved issues. As

images and the client’s dream has a pow¬

the child of an alcoholic, Sue was trying to

erful impact, spontaneously evoking new

directly voice these family ghosts.

perceptions on emotional cognitive and

The second card, entitled reception,

embodied levels.

is the archetype of the mother; the third, creative, that of the father. The images in Sue’s layout constellated the images in her dream. She was powerfully affected.

Second Case Mary came in greatly depleted and desper¬

“Amazing,” Sue responded. “Tarotpy is

ate. She explained that she took care of her

helping me communicate with my intuitive

mother, who was in her early 90s. Mary felt

self.” As the dream phone indicated, Tarotpy

that since childhood she had had to parent

tapped into her cellular connection.

her mother. She was also taking care of her

Sue next focused on the placement she

husband, who had become ill three years

had named strength. Reflecting on the

ago. Mary was the sole bread winner. I sug¬

dream, Sue recognized two acts of strength:

gested that Tarotpy might offer insight into

going into her parents’ room and finding her

what she deemed a hopeless trap.

OSHOZen Tarot: The Transcendental Game of Zen, (c) OSHO International Foundation, www.osho.

com/copyright / Tao Oracle: An Illuminated New Approach to the I Ching, Ma Deva Padma (c) 2002, www.thetaooracle. com, www. embraceart. com)

Tau Protein and Sleep-Wake Cycle

Even the first step of choosing from a variety of decks proved significant: Mary was exercising choice at a time when she felt she had none. Contemplating the random selection of cards, Mary focused on a card depicting a dragon.


“You dreamed of a dragon?” I asked as we both stared awestruck at the card. The dragon symbol is rarely found in tarot; against the odds Mary selected the image from her dream. I inquired how she might feed her inner dragon.

When asked what the dragon image evoked, Mary softened and said: “My animals.” “What do you get from your relationship with your animals?” I asked.

“With my creativity,” she responded. I pointed out that dragon is a symbol for creativity throughout Eastern culture. The synchronicity between her dream and the dragon image dramatically shifted her per¬

“Unconditional love,” she said.

spective; she accessed that unconditionally

She relaxed and became fully present.

loving and creative part in herself and felt

I was impressed by this significant shift.

renewed optimism.

“Oh,” she suddenly remembered, “I had

Tarotpy’s integrative method can accel¬

a dream last night. In my backyard, there

erate the course of discovery, awareness,

was a green creature. It was part snake, part

and transformation, reducing what may

alligator—Oh! It was a dragon and I was

take months or years of treatment to a few

feeding it.”

sessions. Through actively engaging with imagery, a client can transform entrenched unconscious patterns and have more con¬ scious choice over attitudes and behavior. The synchronicity between dreams and images creates awe-inspiring moments that prompt healing of the mind, body, and spirit and reconnect us with our inner ca¬ pacity for self-awareness and wholeness. Lauren Schneider

References Padma, D. (1994) Osho zen tarot. New York: St. Martin’s Press. Waldherr, K. (1997). Lover’s path tarot. Stam¬ ford, CT: U.S. Games Systems.

Tau Protein and Sleep-Wake Cycle SE^EN OF STAVES (Kris Waldherr)

Tau is a neuronal microtubule-associated protein







Tau Protein and Sleep-Wake Cycle

stabilization, axonal establishment, and

bouts. Altered sleep structure in tau knock¬

elongation during neuronal morphogenesis

out mice is accompanied by a decline in

(Avila, Lucas, Perez, & Hernandez, 2004).

delta power together with an enhanced

Tau knockout animals, although pheno-

spectral density of sleep spindles during

typically normal, have shown a significant

NREM sleep. REM sleep, however, seems

delay in the axonal extension of hippocam¬

to be unaltered by the lack of tau.

pal neurons and lag in stage development

The mechanistic role of tau protein in

(Dawson et al., 2001), which may affect

the sleep-wake cycle is supported by dif¬

both neural coordination and synaptic ef¬

ferent lines of evidence. Tau interacts

ficiency in local- and long-range circuits.

with the neural membrane through its

This hypothesis has been recently sup¬

amino-terminal projection domain. And

ported by in vivo electrophysiological stud¬

slow-wave activity (1 Hz) and excitatory effects when pre¬

memory task (thus, approximately 60 to 90

sented at high frequencies (>5 Hz).

minutes poststimulation). In another well-

Although TMS studies have not yet di¬

controlled study, Nitsche et al. (2010) in¬

rectly examined dreaming, some have in¬

vestigated the effects of tDCs applied to

vestigated hallucinations, sleep states, and

the prefrontal cortex during REM sleep

consciousness. For instance, the results of

on the consolidation of a motor sequence

a recent meta-analysis have supported the

learnt before sleeping. It was found that

conclusion that low-frequency rTMS over

anodal tDCs stimulation of the prefrontal

the temporoparietal junction is effective in




Use of Noninvasive Techniques in the Study of Dreaming

reducing auditory hallucinations in schizo¬

that cognitive effects may be observed

phrenia (see George et al., 2009). In regard

when such stimulation is directed at brain

to sleep, Massimini et al. (2010) found that

regions implicated in the dream report pro¬

from TMS of the right premotor cortex dur¬

cess. The most suitable cortical targets for

ing short-wave sleep SWS produced very

tDCs would therefore be the prefrontal and

focal high-density multisite EEG activa¬

the PTO association cortex due to: (1) its

tion patterns localized at the site of TMS

accessibility with tDCs (compared to the

stimulation. However, TMS applied dur¬

brain stem, thalamus and anterior cingulate

ing REM sleep triggered more widespread

gyrus), and (2) the fact that these regions

and differentiated cortical EEG activation

are implicated as key cortical regions in

patterns, similar to that found during wake¬

dream reporting as evidenced by neuroim¬

fulness. Consistent with this result, Ferra-

aging and lesion studies.

relli et al. (2010) administered TMS to a

Antonia J. Jakobson, Paul B.

group of healthy individuals during wake¬

Fitzgerald, and Russell Conduit

fulness as well as during pharmacologi¬ cally induced loss of consciousness. They

See also: entries related to Sleep and the Brain;

found that compared to wakefulness, TMS

entries related to Sleep Assessment

applied during a loss of consciousness was characterized by short-lasting local activity


that failed to propagate beyond the site of

Antal, A., & Paulus, W. (2008). Transcranial direct current stimulation and visual percep¬ tion. Perception, 37, 367-374.

stimulation. Thus, such authors have con¬ cluded that the EEG responses observed during SWS and loss of consciousness reflect a breakdown in cortical effective

Ferrarelli, F., et al. (2010). Breakdown in cortical effective connectivity during midazolam-induced loss of consciousness.

connectivity and that the spread of cortical

Proceedings of the National Academy of

activity observed during REM sleep repre¬

Science U.S.A., 107, 2681-2686.

sents intact consciousness, possibly dream consciousness, which is disconnected from the outside world. No study to date has in¬ vestigated the relationship between such cortical interconnectivity and dreaming.

Conclusions Currently, no study has examined the ef¬ fect of TMS or tDCs during sleep related to subsequent dream reporting. If TMS and tDCs can affect cognitive functioning in both waking and sleeping participants, as demonstrated by several previous stud¬ ies, then it is not unreasonable to propose

Fregni, F., et al. (2005). Anodal transcranial di¬ rect current stimulation of prefrontal cortex enhances working memory. Experimental Brain Research, 166, 23-30. George, M.S., et al. (2009). Controversy: Re¬ petitive transcranial magnetic stimulation or transcranial direct current stimulation shows efficacy in treating psychiatric dis¬ eases (depression, mania, schizophrenia, obsessive-compulsive disorder, panic, posttraumatic stress disorder). Brain Stimula¬ tion, 2, 14-21. Marshall, L., Molle, M., Hallschmid, M., & Born, J. (2004). Transcranial direct current stimulation during sleep improves declara¬ tive memory. The Journal of Neuroscience, 24, 9985-9992.

Using Dreams in Cognitive-Behavioral Therapy

Massimini, M., et al. (2010). Cortical reactiv¬ ity and effective connectivity during REM sleep in humans. Cognitive Neuroscience, 1, 176-183. Nitsche, M.A., et al. (2008). Transcranial di¬ rect current stimulation: State of the art 2008. Brain Stimulation, 1, 206-223. Nitsche, M. A., et al. (2010). Contribution of the premotor cortex to consolidation of motor sequence learning in humans dur¬ ing sleep. Journal of Neurophysiology, 104, 2603-2614. Zaghi, S., et al. (2010). Noninvasive brain stimulation with low-intensity electrical currents: Putative mechanisms of action for direct and alternating current stimulation. The Neuroscientist, 16, 285-307.


example, Arthur Freeman has been doing so and found that dream content can be subject to the same cognitive restructuring (change of viewpoint) as waking thoughts, and Barry Krakow has developed an effi¬ cient treatment for recurrent nightmares. The use of dreams in CBT can be gener¬ alized if therapists adopt a conception of dreaming radically different from those of psychoanalysts and an interpretation method compatible with the methodology and principles of CBT. As far as the con¬ ception of dreaming is concerned, Beck already stressed the continuity between dream content and mental representations in the waking. Montangero (2009) pre¬ sented a cognitive conception in which

Using Dreams in CognitiveBehavioral Therapy

dreams are the extreme form of thinking with relaxed control, on a continuum start¬ ing with spontaneous remembrances and

Working with dreams is very unusual

anticipations. He explained the specifics

among psychotherapists practicing cogni¬

of dream content by the deactivation of

tive-behavioral therapy (CBT). Yet Aaron

certain cognitive abilities (executive func¬

Beck, one of the main founders of cogni¬

tions) and by the necessity of representing

tive therapy, advocated the use of dreams

ideas in a concrete, at least partly visual,

in a 1971 paper, asserting that the cli¬

and economic way. According to him,

ents’ idiosyncratic way of conceptualizing

dreams can express any topic of interest

themselves and the outside world greatly

or concern for the dreamer, usually when

influenced dream content. However, any

it has been insufficiently processed in the

reference to dreams disappeared from the


subsequent writings of Beck and of his

As far as dream interpretation is con¬

main followers. The reasons were, first,

cerned, Montangero proposes a method

that dreams were closely associated with

according to which the therapist has no

psychoanalysis, second that their experi¬

preconceived idea as to what the dream is

mental study was difficult and, third, that

about. The meaning of the dream (i.e., the

behavioral therapists, with whom Beck

relationship between the dream and con¬

started a close relationship, were not inter¬

cerns, topics of interest, and life episodes

ested in such material.

of the dreamer) is discovered thanks to

Only a very limited number of CBT

the descriptions, memories, and personal

therapists have been using dreams (see

ideas of the client related to the dream con¬

Rosner, Lyddon, & Freeman, 2004). For

tent. The work with the dream comprises




Using Dreams in Cognitive-Behavioral Therapy

three steps before the client finds an inter¬

Once these topics are discovered, the

pretation (which is the fourth step). First,

therapist can use them in various ways, for

the complete description of the dream im¬


merses the client in the memory of the dream experience. Everything that was vi¬ sualized and everything that was present

client’s life. •

without being visualized has to be men¬

Draw the client’s attention on the biased way of representing the topic, which is often par¬

tioned, concerning the events or actions, the setting, the characters, and possible

Discuss the importance of this topic in the

ticularly apparent in the dream representation. •

Ask the client whether there would be a

objects. The client is also asked whether

more realistic and pleasant way to deal with

s/he felt an emotion during the dream scene.

the same situation.

The second step is the systematic search for memory sources. The client is asked what memory comes to his/her mind about each main element of the dream report. For in¬ stance, “What memory comes to your mind about elephants?” and not “about the small brown elephant of your dream.” For each retrieved memory source, the client spec¬ ifies its subjective meaning; that is, the ideas and emotions linked to that episode. Third, the client is asked to reformulate the

Underline any representation in the dream of the client’s resources.

This kind of dreamwork yields comple¬ mentary information about the client and provides concrete and metaphorical repre¬ sentations of his/her problems and strate¬ gies. Research on the impact of dreamwork in CBT is needed, and will be possible when a sufficient number of therapists use a similar method. Jacques Montangero

dream report by replacing the words of the initial report by a personal definition of the element, or by its function, its encom¬ passing category, or the subjective mean¬ ing of the memory source related to that content. This reformulation in general terms usually permits the client to discover relationships between the dream report and concerns, topics of interest, or life episodes.

See also: Cognitive Approach to Dreaming

References Montangero, J. (2009). Using dreams in cognitive-behavioral therapy: Theory, method and examples. Dreaming, 19, 239-254. Rosner, R. I., Lyddon, W.J., & Freeman, A. (Eds). (2004). Cognitive therapy and dreams. New York: Springer.

V Video Game Play and Dreams

that while nonplayers trained with up to 1,000 hours of play improved their perfor¬

It is important to consider why video game

mance, they did not reach the skill levels

play is relevant for understanding dreams.

on the cognitive/perceptual tasks as expert

Several points can be made. First, Revon-

players. Boot et al. (2011) estimated ex¬

suo (2009) argues that dreams are useful

pert players came into the laboratory con¬

for understanding the binding problem in

dition with tens of thousands of hours of

consciousness. He defines consciousness-

video game play. One can make the case

related binding as the connection between

that high-end gamers bring to research a

our personal sense that our conscious¬

lifetime of neuronal network effects that

ness is unified and the underlying biologi¬

may depart from ordinary conscious expe¬

cal mechanisms. This is illustrated in the

riences including dreams.

dream state with its inherent bizarre nature.

The second reason why inquiry into

While during waking these semantic neu¬

video games is important for dream re¬

ral networks are hidden, due to the dom¬

searchers deals with one potential evo¬

ination of sensory stimuli, dream study

lutionary function of dreaming, threat

allows for their unfettered examination.


In other words, bizarreness in dreams illu¬

dealing with threats in dreams has evolu¬

minates semantic neuronal networks. One

tionary functionality in that it would re¬

type of bizarreness happens due to a skip

sult in better performance in subsequent

in the track of the semantic network but it

waking. Video gaming may reduce this

does not go too far afield. Other types of

dream function because this need is being

bizarreness indicate major departures from

addressed in another imaginal realm (i.e.,

a given network.

during a video game). Thus, video gaming




Thus, having a waking situation, namely

offers the potential to investigate this evo¬

video game play, where subjects are ex¬

lutionary function of dreams. Relatedly,

posed for long periods of time to unusual

threats in dreams are often nightmarish.

or bizarre experiences, can help to fur¬

Thus, the rehearsal of nightmares while

ther illuminate the nature of bizarreness

awake as a technique to decrease their in¬

in dreams. Such a situation is not easily

tensity and persistence can be argued is the

created in a laboratory with a few hours

essence of some video games.

of viewing or interacting with media. In

The third reason that studying video

fact, in a study of video game effects on

gaming informs dream studies is the po¬

various cognitive and perceptual tasks,

tential of video gaming to act as prepara¬

Boot, Blakely, and Simons (2011) found

tion or training for dreaming lucidly and




Video Game Play and Dreams

commanding some control over the dream

exposure on dreams is important in and

as it progresses. Practice in this technolog¬

of itself. Although video games are escap¬

ically generated imaginal realm seems to

able, and dreams typically less so (an ex¬

be associated with consciousness emerg¬

ception being lucid-control dreams), there

ing in dreams. Thus such inquiries inform

are many parallels between them in the

not only the question of how to have a lucid

sense that video games offer experience

dream but also the broader question of the

in an alternative reality that is accessible

nature of consciousness when it emerges in

by most people. Other alternative reali¬

sleep. Likewise, gamers are well practiced

ties, such as those created in hypnosis, are

and expect to be in command of threaten¬

less widely accessible. Video gaming pro¬

ing enemies in virtual worlds so that in the

vides experiences in deep absoiption not

biologically virtual world of the dream this

normally available to those without access

skill is quickly utilized. In other words,

to experiences that can result in alternative

gamers show more dream control.

realities. Supporting this conjecture is a re¬

Finally, on a pragmatic level, video

cent study in our laboratory. We found that

games offer an opportunity for sleep and

the degree of self-reported presence, sense

dream researchers to manipulate presleep

of being there, in dreams versus in a video

stimuli within closely controlled condi¬

game was not different, belying the oft-

tions. An easily controlled and impactful

cited assumption that dreams are the gold

presleep event is the use of a film to in¬

standard of presence.

vestigate the nature of dream incorpora¬

As communication studies history has

tion. Films have been used to investigate

taught, the typical introduction of new

stress. The advantage of a film is it allows

media is accompanied by fearful reactions

presleep controlled manipulation to inves¬

from the public and existing media. Thus

tigate incorporation questions.

negative findings such as modeling of ag¬

However, as our media landscape is

gression, the potential for addiction, and

changing, so too are our opportunities to

lack of physical activity are most often

use media to investigate issues of dream

discussed. However, numerous positive

incorporation. The problem with film, tele¬

consequences of video game play have

vision, or radio is that they are all unidirec-

also been found from practice in social

tionally presented, or pushed at the passive

realms to various improvements in cog¬

viewer. In our waking lives we are not pas¬

nitive skills. Our research effort has been

sive viewers, but active participants. This

the impact of video game play on night¬

active participatory element is captured in

time dreams. That impact could have been

computer use and, especially, video game

positive or negative, but it appears to be


associated with largely positive dream out¬

It is important to keep in mind that due

comes. Video game play may act as a type

to the increasing gaming pervasiveness

of meditative experience to the extent that

in North American society, 67 percent

it requires similar levels of attentional ab¬

of homes report video game play (ESA,

sorption. Video gaming enhances the expe¬

2011), and the effects of such VR-type

rience of dream lucidity along the lines of

Video Game Play and Dreams


meditators’ experiences of lucidity. These

2009) was for data from subjects who re¬

findings can be interpreted equally in terms

ported normal sleep length where they felt

of a psychology of imaginative absorption.

rested. Of the 800 plus college student re¬

The question posed in our laboratory

spondents, only 152 fit these criteria. In a

is what are the effects on the biologically

factor analysis of these dreams with dream

constructed alternative realities of dreams

type, media use, and gamer-history infor¬

by immersion in the technologically con¬

mation, lucid and control dreaming were as¬

structed worlds experienced during video

sociated with high-end gamer history and

game play? Throughout these studies we

heavier media use the day before the dream.

generally defined the hard-core gamer as

While video game play was the marker on

someone who:

this factor, all media use was associated

1. Plays video games on average several times a week, 2. Has a typical playing session of more than 2 hours; 3. Played 50 or more video games over their lifetime; and 4. Has been playing video games since grade three or earlier.

with lucid and control dreams. This is im¬ portant to note as while not everyone may be gaming, just about everyone is using var¬ ious electronic media and thus engaged to some extent in virtual worlds. However, the lucid-dream-gaming asso¬ ciation is less robust than the control-dream¬ gaming link. When asked to provide lucid dreams there was no difference between

The dream dimensions that we have

high- and low-end gamers in their self-

examined thus far include lucid dreams,

reported incidence. But control of dreams

dreams where you know you are dream¬

seems to emerge as superior in high-end

ing while the dream is ongoing; control

gamers across data-collection methods. This

dreams, where the dreamer has control over

difference was most recently illuminated in

some aspects of the dream; bizarreness,

a study where gamers were compared to two

the degree to which dreams are unusual or

other groups frequently engaging in absorb¬

odd; and nightmares, dreams that are so

ing activities, for example, prayer/medita-

frightening that they wake the sleeper.

tion and control group. Those who pray/ meditate a lot had the highest levels of lu¬

Lucid and Control Dreams

cidity but gamers were significantly higher on lucidity than any other absorbing activ¬

In several studies we were able to show

ity group. However, when it came to dream

that high-end gamers had more lucid and

control, it was gamers who reported signifi¬

control dreams than those who rarely game

cantly more than both of the other absorb¬

(Gackenbach & Kuruvilla, 2008). This

ing groups.

dream information was initially based on

Why might we expect this parallel be¬

retrospective reflections on dream history

tween video game play and lucid-control

and more recently on dream reports from

dreaming? There are several reasons.

the previous night’s sleep. The first of

Video games are technologically con¬

these last night dream studies (Gackenbach,

structed alternative realities while dream




Video Game Play and Dreams

worlds are biologically constructed alter¬

groups. In addition to the online dream-

native realities. One could argue that there

diary study we also asked the research par¬

is simply a practice effect. If you are in an

ticipants about features that were bizarre

artificial reality for hours a day, is it any

for the subjects themselves, as well as vari¬

surprise that you recognize something sim¬

ous media-use information. For those who

ilar when you are in another one at night?

fulfilled the criteria for the dream-diary

Video gaming has been associated with

component of the research project, we ad¬

improved spatial skills as has lucid dream¬

ministered a verbal and figural creativity

ing. A lack of proneness to motion sick¬

test. It was found that high-end gamers had

ness is needed to play a lot of these games

more bizarre than nonbizarre dreams than

and lucid dreamers have better vestibular

low-end gamers of both the self-reported

systems; thus, they are not susceptible to

and judges’-reported types, while the op¬

motion sickness. Finally, the high attention

posite was the case for nonbizarre dream

and absorption reported by players and in

elements. It is important to point out that

research on gaming is reminiscent of the

media use the day before was controlled,

same qualities associated with meditation,

and therefore a straight incorporation of

a group that has been found to have very

bizarre game or other media elements into

high levels of lucidity in sleep.

the dream does not account for this find¬ ing. In terms of the creativity assessment, no significant difference for verbal test re¬

Dream Bizarreness

sulted but significant differences for the fig¬

Based on dreams collected and analyzed in

ural test favoring the high-end gamer group

hour-long interviews with hard-core gam¬

were identified. We concluded that bizarre¬

ers, higher imaginal and dead characters

ness in gamers’ dreams is at least associated

were found in gamers’ dreams than in the

with their creativity and with their history

norms (Gackenbach et al., 2009). We pur¬

of media use in the form of gaming, but not

sued this bizarreness finding in gamers’

associated with the day before media use.

dreams in two additional studies (Gack¬ enbach, Kuruvilla, & Dopko, 2009). In the first of these two studies (Gackenbach


et al., 2009) recent dreams were collected

Due to our findings in an interview study

in an online questionnaire from college

of high-end gamers (Gackenbach et al.,



2009), we became curious about night¬

tion was also gathered. It was found that

mares. Less misfortune and more intense

high-end gamers evidenced more bizarre

aggression, when it happened but occur¬

dreams than low-end gamers in two of the

ring less often, was found among these

three types of bizarreness categories.

hard-core gamers. This combination of



In the second study a two-week online

findings led us to wonder about gamers’

dream diary was gathered from preselected

nightmares. We explored this question

research participants who varied on the

with additional content analysis on larger

four game-play criteria mentioned earlier.

samples of gamers’ dreams (Gackenbach &

This resulted in high- and low-end gamer





Video Game Play and Dreams


aggression and misfortune findings. Thus

When we examined the dreamers self-

three studies were undertaken to further

reported emotions during these two types of

examine these results. In all three studies

negative dreams, negative emotions (anxi¬

threat simulation, as an explanation for the

ety, frustration, and fear) were found to be

aggression and misfortune findings, was

higher in bad dreams for high-end gamers,

explored (Gackenbach & Kuruvilla, 2008).

while positive emotions (sexual arousal

Revonsuo (2009) argues that dreaming

and happiness) were found to be greater

is an adaptive process with an evolution¬

in nightmares for high-end gamers. When

ary foundation. It allows us to simulate

these same dreams were analyzed for threat

threatening situations in the safety of a

simulation as a function of gamer history,

virtual environment of dreams. This con¬

there was an interaction between dream

tinued practice during dreaming would

type (nightmare x bad dream) and gamer

allow an individual to better prepare for

group (high vs. low). The high-end gamers

these possibly dangerous instances, were

showed the expected less threat in night¬

they to arise in the waking world. Gack¬

mares but more in bad dreams while the

enbach and Kuruvilla (2008b) asked the

low-end gamers evidenced less of a differ¬

question, might gamers’ dreams be lower

ence in threat between the two dream types.

in threat simulation because they have al¬

This study was followed by one examin¬

ready practiced these responses in their

ing soldiers who play video games. In this

game play during the day? Revonsuo

case they were asked for a recent dream

(2000) method of dream content analysis

and a military dream. Information was also

for threat simulation was used on these

gathered on these military gamers’ emo¬

dreams experienced the night before filling

tional reactivity and history of trauma, in¬

out the questionnaire. In a factor analysis

cluding military, which has been shown to

of media use (including gaming history),

be predictive of nightmares. When these

threat simulation content variables, and

predictive factors were controlled, fre¬

various self-report variables of dream con¬

quent gaming was associated with signifi¬

tent, we found that when high-end gam¬

cantly less threat in military dreams. Thus

ers reported playing a lot of games the

it may be that high-end gaming may act

day prior to a reported dream, there was

as an inoculation against the nightmare at

no association to threat in their dreams nor

least in situations where there is real-world

were these dreams seen as nightmarish or

threat, such as being deployed for war.

scary by the gamers despite reporting that the dreams were violent. In contrast, the low-end gamers did not play games the

Conclusions and Implications

day before the dream but did watch vio¬

Three general dream types have been

lent television shows or movies and had

examined in our program looking at the

dreams that were not only high in threat

relationship between video game play and

simulation, but also in violence, nightmar-

dreams. A participant-observer gamer in

ishness, and scariness. Thus we concluded

our research program illuminates our major

that gaming might be viewed as a protec¬

findings. When asked, he responded that

tion against threat simulation in dreams.

yes his dreams were lucid and bizarre, and




Visual Art and Dreams

he sometimes has aggression in his dreams but rarely nightmares. Rather he pointed out that he was in the third person in his dreams: I’ve just noticed that sometimes I’m just there as a hovering spirit watching things go on and I don’t really have a role . . . I don’t even pop up in my dreams, it’s just like I’m watching a movie ... I feel emotion definitely regardless of whether or not I’m the person involved. (Jordan Olischefski; Gackenbach et ah, 2009)

In this entry, we reviewed three major areas of inquiry into dreams of gamers: lucid/control dreams, bizarre dreams, and nightmares. We have found higher lucid/ control dreams in gamers and wonder if this is indicative of improved metacogni¬ tion in dreams. Increased bizarreness in gamers might imply that gamers are capa¬ ble of improved novel adaptive responses as per the global workspace theory of con¬ sciousness or creativity. Finally, in terms of aggression/misfortune in dreams we found some association between gaming serving a threat simulation function in waking and potentially a protective function regarding nightmares, if not bad dreams. While not entirely clear, taken together it seems that

ESA (2011). http://www.theesa.com/Entertain merit Software Association. Gackenbach, J.I. (2008). Video game play and consciousness development: A transper¬ sonal perspective. Journal of Transpersonal Psychology, 40(1), 60-87. Gackenbach, J.I. (2009). Electronic media and lucid-control dreams: Morning after reports. Dreaming, 19(1), 1-6. Gackenbach, J.I., Ellerman, E., & Hall, C. (2011). Video game play as nightmare pro¬ tection: A preliminary inquiry on military gamers. Dreaming: APA ’s Online First (August 22, 2011). Gackenbach, J.I., & Kuruvilla, B. (2008). The relationship between video game play and threat simulation dreams. Dreaming, 18(4), 236-256. Gackenbach, J.I., Kuruvilla, B., & Dopko, R. (2009). Video game play and dream bizarre¬ ness. Dreaming, 19(4), 218-231. Gackenbach, J.I., Matty, I., Kuruvilla, B., Samaha, A.N., Zederayko, A., Olischefski, J., & Von Stackelberg, H. (2009). Video game play: Waking and dreaming consciousness. In S. Krippner (Ed.), Perchance to dream (pp. 239-253). Hauppauge, NY: Nova Sci¬ ence Publishers. Gackenbach, J. I., Rosie, M., Bown, J., & Sam¬ ple, T. (2011). Dream incorporation of video game play as a function of interactivity and fidelity. Dreaming, 21(1), 32-50.

while awake may make positive contribu¬

Revonsuo, A. (2000). Behavioral and Brain Sciences, 23(6), 887-901; discussion 904— 1121. Review.

tions to dreaming and is reminiscent of

Revonsuo, A. (2009). Inner presence: Con¬

a case can be made that video game play

sciousness as a biological phenomenon.

meditators’ dreams.

Cambridge, MA: MIT Press. Jayne Gackenbach

See also: entries related to Dream Content

References Boot, W.R., Blakely, D.P., & Simons, D.J. (2011). Do action video games improve per¬ ception and cognition? Frontiers in Psychol¬ ogy, 2, 226.

Visual Art and Dreams Historically widespread concepts of the dream as sometimes prophetic and su¬ pernatural in origin lie behind the most

Visual Art and Dreams


obviously dream-related visual art, which

The 19th and 20th centuries opened up a

depicts specific dreams of important spiri¬

broader set of options for the visual arts to

tual and historic figures, often representing

engage dreaming. Changes in the role of the

both dreamer and dream. Such artworks

artist and art patronage, associated with the

were initially generated and viewed in a

rise of individualism and the bourgeoisie,

context of understanding shared by patron,

enabled artists to explore dream experience

artist, and audience. In European Chris¬

from more personal and introspective per¬

tian art, especially in medieval illuminated

spectives. Romanticism, with its valoriza¬

manuscripts and church sculpture, the Bib¬

tion of subjective experience; symbolism,

lical dreams of Jacob, the Pharaoh, and the

with its interest in hidden meaning; modem

Three Magi are the most frequently repre¬

abstraction, with its disorienting approaches

sented, with some attention to dreams of

to the material world; and especially surre¬

saints in Renaissance paintings. Through¬

alism, with its explicit focus on the dream,

out the Buddhist diaspora, the dream of

offered fertile ground for dream content. In

Maya, mother-to-be of the Buddha, has

recent years, a number of survey exhibi¬

been the basic dream subject. In Islamic

tions with substantial catalogues in North

manuscript illuminations, the night visions

America and Europe have mapped the terri¬

of the Prophet epitomize the divine dream.

tory, though further dream-specific studies

South Asian art, especially in illustrated

would be helpful for every artist, move¬

manuscript books, draws on the Hindu

ment, and period involved. Lynn Gamwell’s

Puranas for dream stories. In Egyptian and

landmark exhibition assembled a particu¬

Greco-Roman antiquity, iconic sculptural

larly comprehensive look at 20th-century

figures of gods and goddesses associated

art of the dream; her essay in the catalogue

with dream incubation (such as Asklepios,

Dreams 1900-2000: Science, Art, and the

Amphiarion, Isis, and Serapis) were in¬

Unconscious Mind (2000) addresses the in¬

stalled at incubation sites.

fluence of Freud on art, proposing that two

Many tribal and indigenous cultures

major streams of 20-century art-making, the

create visual mappings and artifacts refer¬

unconscious mind and art-about-art, would

ring to shamanic and initiatory journeys

have been inconceivable without Freud’s

in dream and to dreams of special signifi¬

theories of the dream and the unconscious.

cance to the community or an individual.

Neuroscientist J. Allan Hobson and art his¬

A useful gathering of such work, with

torian Hellmut Wohl detail correlations be¬

brief commentary, is provided by David

tween late 20th-century neuroscience of the

Coxhead and Susan Hiller in their gen¬

dreaming brain and Western art 1780-1950

eral survey Dreams: Visions of the Night

in From Angels to Neurones: Art and the

(1976), including examples from Iroquois,

New Science of Dreaming (2005). An ex¬

Chumash, Chippewa, and Navajo Native

emplary in-depth study of a single work is

American tribes, shamanic traditions of

Norman Gee’s Ernst: Pieta or Revolution

northern Europe and Asia, aboriginals in

by Night (1986), which traces Max Ernst’s

Central Australia, and the Saora in Orissa,

deployment of Freud’s dream theory both in


process and in content.




Visual Art and Dreams

Dream of the Magi, stone capital, Cathedrale Saint-Lazare, Autun, by Gislebertus (French, 12th cen¬ tury). (GiraudonFThe Bridgeman Art Library International)

The later 20th century and early 21st

to visual art. In The Committee of Sleep:

century have again expanded the range of

How Artists, Scientists, and Athletes Use

dream-related visual art. New art media and

Dreams for Creative Problem-Solving—

formats such as video and the artist book

and How You Can Too (2001), Deirdre

have proven especially receptive to dream

Barrett opens with a chapter on painting

content. In contemporary performance and

and sculpture which interrogates with nu-

installation art, the public or documented

anced understanding a few dozen histori¬

act of dreaming may be itself the artwork.

cal and contemporary examples, including

Art-making practices such as collage have

Salvador Dali, Frida Kahlo, and Jasper

been developed as dreamwork methods,


shifting perceptions of dream art from pro¬

With the possible exception of medieval

fessional artists and passive viewers to a

European work, which has been well stud¬

participatory workshop context with aims

ied, the entire field is still wide open for

beyond the boundaries of traditional art

dream-focused studies that integrate con¬


cepts of the dream, the science of dream¬

Studies of the functions of dreaming

ing, and dreamwork practices with visual

in creativity have particular relevance

art perspectives. Asian, Middle Eastern,

Visual Art and Dreams


and indigenous contexts especially need

for creative problem-solving—and how you

far more attention. Studies that include

can too.

New York: Crown Publishers.

and process in contemporary work could

Coxhead, D., & Hiller, S. (1976). Dreams: Vi¬ sions of the night. New York: Crossroad.

be facilitated by the backlog of artist inter¬

Gamwell, L. (Ed.). (2000). Dreams 1900-

the voice of the artist on issues of origin

views and statements gathered in periodi¬ cals such as Dreamworks in the 1980s and DreamTime since the 1990s. Betsy Davids

2000: Science, art, and the unconscious mind.

Ithaca, NY: Cornell University

Press. Gee, N. (1986). Ernst: Pieta or revolution by night. London: The Tate Gallery. Hobson, A., & Wohl, H. (2005). From an¬


gels to neurones: Art and the new science

Barrett, D. (2001). The committee of sleep: How

of dreaming.

artists, scientists, and athletes use dreams

Fidenza: Mattioli. (Originally published in 1885.)





w White Noise and Sleep

who reported waking more than once per night or taking longer than 30 minutes to

College students require between eight

fall asleep to participate in a study examin¬

and nine hours of sleep every night for

ing the efficacy of continuous white noise

peak performance during the day; how¬

for reducing sleep difficulties in college

ever, research indicates that most only

students. These students were provided

receive between seven and eight hours

with a Tranquil Moments Plus white noise

each night (Carskadon, 2002). In addition,

generator. Participants were instructed to

Forquer and colleagues (2008) found that

use the white noise setting between 60

33 percent of college students at North Cen¬

and 75 decibels and set to play continu¬

tral University, in Minneapolis, reported

ously from bedtime to wake time. Partic¬

sleep latencies of more than 30 minutes and

ipants kept sleep diaries throughout the

43 percent reported waking more than once

course of the experiment in which they

each night. Finally, a survey by the Amer¬

recorded their bedtime, sleep latency,

ican College Health Association (2005)

number and length of night-wakings, and

reported that college students rated sleep

rise times. White noise generators were

difficulties as the third-largest impediment

implemented according to a nonconcur¬

to academic performance, behind stress and

rent multiple baseline across subjects de¬

illness. Therefore, it was hypothesized that

sign, which involved baselines of varying

improving sleep in college students may be

lengths and introduction of white noise

associated with complementary improve¬

at different points in time for each par¬

ments in academic performance.

ticipant. All four participants reported de¬

Several strategies have been shown to

creases in both frequency of night-waking

help college students sleep better at night,

and sleep latency while using the white

including maintaining a consistent sleep

noise; however, some of their sleep diffi¬

schedule, improving sleep hygiene, and

culties returned to baseline levels follow¬

the use of continuous white noise. Con¬

ing discontinuation of the sound. Attempts

tinuous white noise, sound that covers

to link improved sleep using white noise

the entire range of human hearing from

to improved academic performance were

20 to 20,000 Hz, has been shown to im¬

largely unsuccessful due to the types of

prove sleep in adults and small children,

cognitive measures being utilized. The

but had never been systematically exam¬

free association task employed was too

ined in college, students. Forquer and John¬

easy, leading to potential ceiling effects.

son (2007) recruited four college students

Finally, students reported that they were




Women’s Dreams across the Life Cycle

comfortable using white noise and would recommend it to other students experienc¬

and night waking in college students. Sleep and Hypnosis, 9, 60-66.

ing sleep problems. There are several possible explanations for the effectiveness of continuous white noise for reducing sleep difficulties, includ¬

Women’s Dreams across the Life Cycle

ing decreased arousal through the process of habituation, masking extraneous noises

The notion that dreams reflect the concep¬

that may interfere with sleep, the resetting

tion of the self, of its relation with others,

of the biological clock so that it does not in¬

and with the environment is well suited to

clude frequent night-waking or long sleep

explore changes in women’s dreams par¬

latencies, and stimulus control. Stimulus

allel to developmental changes in waking

control is the process by which white noise

life (Hall, 1953). While content analysis

may come to act as a discriminative stim¬

of long dream series suggests that few

ulus in the presence of which decreased

changes take place in a person’s dreams

arousal is reinforced by sleep causing sleep

throughout adulthood (Domhoff, 2003),

to occur more frequently in its presence.

cross-sectional studies of home-collected

Additional research is needed with larger

dreams found changes, starting in early

samples, possible group designs, and the


use cognitive tasks that more closely re¬ semble actual academic performance. LeAnne M. Forquer

A study by Brenneis (1975), taking into account psychosocial changes from early adulthood to the 70s, led me to explore dreams of different age groups. While no

See also: Increasing Sleep Complaints

evidence of drastic changes was found in the dreams of women from their mid¬


dle 20s to the 40s, the impact of develop¬

American College Health Association. (2005). The American College Health Associa¬ tion National College Health Assessment (ACHA-NCHA), Spring 2003 reference group report. Journal of American College Health, 53, 199-210.

mental changes became noticeable by the

Carskadon, M. A. (2002). Adolescent sleep pat¬ terns: Biological, social, and psychological influences. New York: Cambridge Univer¬ sity Press. Forquer, L. M., Camden, A. E., Gabriau, K. M., & Johnson, C.M. (2008). Sleep patterns of college students at a public university. Journal of American College Health, 56, 563-565. Forquer, L.M., & Johnson, C.M. (2007). Con¬ tinuous white noise to reduce sleep latency

middle 50s (Cote, Lortie-Lussier, Roy, & De Koninck, 1996). Inconsistent or mar¬ ginally significant results of other studies, resulting from small samples or from dif¬ ferences in data collection, limit the gener¬ alization of their findings. More systematic and inclusive studies were in order to trace the ontogenetic evolution of dreams from adolescence up to old age. A large study of the dreams of Canadian women and men, Francophone and Anglophone, ranging in age from 12 to 80 years, was initiated in 2005 at the University of Ottawa by Joseph De Koninck.

Women’s Dreams across the Life Cycle

Home dream reports have been collected since then in Ottawa, the National Capital


finding meaningful relationships find their way in dreams.

of Canada. Participants were contacted in

The dreams of the 25 to 39 group are

high schools, universities, workplaces, and

as lengthy as those of the younger adults,

community centers. The present sample in¬

with a marked decrease in the number of

cludes 412 women, distributed in five age

characters, male and female, and in the fre¬

groups: 88 from 12 to 17, 81 from 18 to

quency of aggressions. Dreamers entertain

24, 80 from 25 to 39, 82 from 40 to 64, 81

more friendly interactions with familiar

from 65 up. One or two dreams from dif¬

characters than any other group, suggest¬

ferent nights were collected with instruc¬

ing intimacy, accentuated by interior set¬

tions to report as many details as possible.

tings. Emotions are similar to the younger

Two independent judges scored them with

women’s. The high incidence of failure is a

the Hall and Van De Castle categories.

unique characteristic, while success is only

Data were submitted to statistical analy¬

occasional. Continuity with waking is re¬

ses, after controlling for length. Reporting

flected in concerns central to that period,

of the results takes into account psycho¬

including marriage or partnership, work

social changes characteristic of successive

and children. The conception of the self is

life stages.

one of inward reflection.

Findings relative to adolescence support

In the middle adulthood group, aged

those of previous studies. Teenagers chat

40 to 64, dreams are shorter than the

in their dreams. Highlights of their reports

younger groups’, contain fewer characters

are activities and friendly interactions,

of either sex and less friendly and aggres¬

generally in the company of girls. But the

sive interactions, consistent with previous

reporting is factual and lacks emotion. Of

studies. Three components emerge: the

all age groups they are the most successful.

dreamers are significantly more often ag¬

They portray themselves as victims of ag¬

gressors, more successful, and angrier than

gressions, physical or verbal. Their dreams

any other group. It could reflect the inde¬

reveal little about the age-related task of

pendence and assertiveness women gain as

finding one’s self through relationships

they reach middle adulthood, in line with

with parents and other adults.

theories of female aging. It could refer to

Young adults (18 to 24), mostly uni¬

decreasing happiness, due to unmet expec¬

versity students, have longer dreams than

tations during this period, which coincides

adolescents, with characters most often

with pre- and post-menopause.

females. Friendly and aggressive interac¬

Findings about the oldest group are con¬

tions are more frequent than in the older

sistent with most studies devoted to this pe¬

groups. They are both aggressors and vic¬

riod. This is valid for the length of dreams,

tims of aggressions. Sadness and anger are

decreased number of characters, familiar

distinctive dream features. Success and

and females, friendly and aggressive inter¬

failure are less frequent than in the other

actions, and total of emotions. Two results

adult groups. Overall dreams reflect tense

stand out: the sharp increase in outdoor

relationships with friends. Concerns about

settings and the prevalence of sadness, at




Women’s Dreams across the Life Cycle

variance with other studies. The salience of sadness may reflect a sense of loss, an interpretation that theories about old age would support. This overview of age-related changes in dreams is but a summary of the issues re¬ lating to the inner life of women, during transitions from the security of one period to the unknown perspectives of the follow¬ ing one. Completing the normative study should provide answers. Monique Lortie-Lussier

References Brenneis, C.B. (1975). Developmental as¬ pects of aging. A comparative study of

dreams. Archives of General Psychiatry, 32, 429-434. Cote, L., Lortie-Lussier, M., Roy, M.J., & De Koninck, J. (1996). Continuity and change: The dreams of women throughout adult¬ hood. Dreaming, 6, 187-192. Domhoff, G. W. (2003). The scientific study of dreams: Neural networks, cognitive de¬ velopment, and content analysis. Wash¬ ington, DC: American Psychological Association. Hall, C.S. (1953). A cognitive theory of dreams. Journal of General Psychology, 49, 273-283. Neugarten, B. J. (1979). Time, age and the life cycle. American Journal of Psychiatry, 136, 887-894.

Y Yawning

periods (e.g., predatory carnivores and primates) yawn much more frequently

The yawn is a stereotyped and often re¬

(following a circadian rhythm) than herbi¬

petitive motor act characterized by gaping

vores. In humans, daily frequency of yawn¬

of the mouth accompanied by a long in¬

ing varies between 5 and 15 times per day.

spiration of breath, a brief acme, and then

The diurnal distribution of yawning fre¬

a short expiration of breath. Stretching

quency is illustrated by higher frequency

and yawning simultaneously is known as

upon waking and before sleep.

pandiculation. It is not merely a simple

A good number of clinical and pharma¬

opening of the mouth but a complex co¬

cological data indicate that yawning in¬

ordinated movement bringing together a

volves a group of oxytocinergic neurons

flexion followed by an extension of the

originating in the paraventricular nucleus

neck, a wide dilatation of the pharyngo-

of the hypothalamus (PVN), and project¬

larynx with strong stretching of the dia¬

ing to extrahypothalamic brain areas (e.g.,

phragm and anti gravity muscles.

hippocampus, medulla oblongata, and spi¬

Ethologists agree that almost all ver¬

nal cord). The PVN is an integration center

tebrates yawn. Yawning is morphologi¬

between the central and peripheral auto¬

cally similar in reptiles, birds, mammals,

nomic nervous systems. It is involved in a

and fish. These behaviors may be ances¬

number of functions ranging from feeding

tral vestiges maintained throughout evolu¬

and metabolic balance to sexual behavior

tion, with little variation (phylogenetic old

and yawning. Activation of these neurons

origins). Correlatively, yawning can be vi¬

by dopamine and its agonists, excitatory

sualized as early as 12 weeks during the

amino acids (N-methyl-D-aspartic acid),

period of fetal development.

oxytocin itself, or by electrical stimulation

Systematic and coordinated pandicula-

leads to yawning; conversely their inhibi¬

tions occur in a similar pattern and form

tion by gamma-aminobutyric acid and its

across all animals, and consistently occur

agonists or by opioid peptides and opiate¬

during behaviors associated with cyclic

like drugs inhibit both yawning and sex¬

life rhythms: sleep arousal, feeding, and

ual response. Other compounds modulate

reproduction. Yawning appears as one un¬

yawning by activating central oxytociner¬

directed response to an inner stimulation,

gic neurons: sexual hormones, serotonin,

underlying the homeostasis of these three

hypocretin, and endogenous peptides (ad-


renocorticotropin-melanocyte-stimulating 'If

hormone). Oxytocin activates choliner¬

Species that sleep 8 to 12 hours and alternate




gic neurotransmission in the hippocampus






and the reticular formation of the brain¬

pathology (serotoninergic agents, apo-

stem. Acetylcholine induces yawning via

morphine, acetylcholinesterase inhibitors,

the muscarinic receptors of effectors from

opiate withdrawal) is the most frequent

which the respiratory neurons in the me¬

explanation of pathologic cases.

dulla; the motor nuclei of the 5th,7th, 9th,

Yawning does not accelerate blood

10th, and 12th cranial nerves; the phrenic

flow. This blood-flow theory argued that

nerves (C1-C4); and the motor supply to

yawning improved the oxygenation of the

the intercostal muscles.

brain, in response to cerebral anemia. The inaccuracy of this hypothesis was for¬

Contagiousness of Yawning

mally invalidated by Provine, Tate, and Geldmacher (1987). In his studies, he has

It seems that hominids have the unique ca¬

demonstrated that breathing neither pure

pacity to be receptive to the contagious¬

02 nor gases high in C02 had any signifi¬

ness of yawning. In humans, echokinesis

cant effect on yawning, although both in¬

only occurs in situations of minimal men¬

creased breathing rate. In a second study,

tal stimulation (public transport, waiting);

he has found that exercise sufficient to

people are not susceptible to this phenom¬

double breathing rate had no effect on

enon during prolonged intellectual effort.


Yawning appears to trigger a sort of so¬

Although the available data are far from

cial coordination function and reflects the

providing a complete and generally ac¬

capacity to unconsciously and automati¬

cepted account of the physiological func¬

cally be influenced by the behavior of

tion of yawning, progress has been made

others. Autistic individuals who are char¬

in ruling out previously held hypotheses.

acterized by impaired mental state attri¬ bution do not show contagious yawning. All these data support the hypothesis that


contagious yawning shares the neural net¬

Yawning and pandiculation are transi¬

works implicated in self-recognition and

tional behaviors, universal among verte¬

mental state attribution; it may therefore

brates, closer to an emotional stereotypy

be that yawning is involved in empathy.

than a reflex. Phylogenetically ancient and

Excessive yawning is a source of embar¬

ontogenetically primitive, they may pro¬

rassment in social circles. There are mul¬

vide some evolutionary advantage. They

tiple causes of excessive yawning, that is, a

seem to exteriorize homeostatic processes

cluster of 10 to 50 yawns, many times a day.

of systems controlling wakefulness, sati¬

Of short duration, they may predict a vaso¬

ety, and sexuality in the diencephalon.

vagal reaction or neurovegetative disorders

'Olivier Nils Walusinski

(dyspepsia, migraine-like syndromes). All insults to the intracranial central nervous system or the hypothalamo-hypophyseal region may be involved: tumors with intra¬ cranial hypertension, infections, temporal epilepsy, strokes, etc. Actually, iatrogenic

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Sleep Spindles Berner, I., Schabus, M., Wienerroither, T., & Klimesch, W. (2006). The significance of sigma neurofeedback training on sleep spin¬ dles and aspects of declarative memory. Ap¬ plied Psychophysiology and Biofeedback, 31(2), 97-114.

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Goley, P. D. (1999). Behavioral aspects of sleep in Pacific white-sided dolphins (Lageno-

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Sleep in an Amazonian manatee, Trichechus inunguis. Experientia, 48(4), 417-419. Mukhametov, L. M., Lyamin, O. I., & Polya¬ kova, I.G. (1984). [Sleep and wakefulness in northern fur seals (Callorhinus ursinus)] (in Russian). Zh Vyssh Nerv Deiat lm 1 P Pavlova, 34(3), 465-471. Mukhametov, L.M., Supin, A., & Poliakova, I. G. (1984). [The sleep in Caspian seals (Phoca caspica)] (in Russian). Zh Vyssh Nerv Deiat ImlP Pavlova, 34(2), 259-264. Ridgway, S.H., Harrison, R.J., & Joyce, P. L. (1975). Sleep and cardiac rhythm in the gray seal. Science, 187(4116), 553-555.

Papers with Adult Sea Mammal Data Lyamin, O.I. (1987). [The ontogenetic devel¬ opment of the interhemispheric asymmetry of the EEG during slow-wave sleep in north¬ ern fur seals] (in Russian). Zh Vyssh Nerv Deiat lm 1P Pavlova, 57(1), 157-159. Lyamin, O.I., & Chetyrbok, I.S. (1992). Uni¬ lateral EEG activation during sleep in the Cape fur seal, Arctocephalus pusillus. Neu¬ roscience Letters, 143(1-2), 263-266. Lyamin, O.I., Mukhametov, L. M., & Polyakova, I.G. (1986). [Peculiarities of sleep in water in northern fur seals] (in Rus¬ sian). Zh Vyssh Nerv Deiat lm I P Pavlova, 36(6), 1039-1044. Lyamin, O.I., Mukhametov, L.M., & Siegel, J. M. (2004). Relationship between sleep and eye state in cetaceans and pinnipeds. Archives of Italian Biology, 142, 557-568.

in northern fur seals (Callorhinus ursinus)] (in Russian). Zh Vyssh Nerv Deiat lm 1 P Pavlova, 34(3), 465-471. Mukhametov, L.M., Lyamin, O.I., & Poly¬ akova, I.G. (1985). Interhemispheric asyn¬ chrony of the sleep EEG in northern fur seals. Experientia, 47(8), 1034-1035. Mukhametov, L. M., & Polyakova, I.G. (1981). [EEG investigation of the sleep in porpoises (Phocoena phocoena)] (in Rus¬ sian). Zh Vyssh Nerv Deiat lm 1P Pavlova, 31(2), 333-339. Mukhametov, L. M., & Supin, A. (1975). [EEG study of different behavioral states of freely moving dolphin (Tursiops truncates)] (in Russian). Zh Vyssh Nerv Deiat lm I P Pav¬ lova, 25(2), 396-401. Mukhametov, L. M., Supin, A. Y., & Polyakova, I.G. (1977). Interhemispheric asymmetry of the electroencephalographic sleep pat¬ terns in dolphins. Brain Research, 134(3), 581-584. Mukhametov, L.M., Supin, A., & Poliakova, I.G. (1984). [The sleep in Caspian seals (Phoca caspica)] (in Russian). Zh Vyssh Nerv Deiat lm 1P Pavlova, 34(2), 259-264. Pilleri, G. (1979). The blind Indus dolphin (Plantanista indi). Endeavour, 3, 48-56. Shurley, J.T., Serafetinides, E. A., Brooks, R.E., Eisner, R., & Kenney, D. W. (1969). Sleep in Cetaceans: I. The pilot whale, Globicephala scammoni [Abstract], Psycho¬ physiology, 6, 230.

Lyamin, O.I., Shpak, O. V., Nazarenko, E. A., & Mukhametov, L. M. (2002). Muscle jerks during behavioral sleep in a beluga whale (Delphinapterus leucas L.). Physiology & Behavior, 76(2), 265-270.

Avian Sleep Reference List

Mukhametov, L.M., & Lyamin, O.I. (1994). Rest and active states in bottlenose dolphins (Tursiops truncates) [Abstract], Journal of Sleep Research, 3, 174.

Amlaner, C.J., & Ball, N.J. (1987). A synthe¬ sis of sleep in wild birds. Behaviours, 87, 85-119.

Mukhametov, L.M., Lyamin, O.I., & Poly¬ akova, I.G. (1984). [Sleep and wakefulness

Ainley, D.G. (1978). Activity patterns and so¬ cial behavior of on-breeding Adelie pen¬ guins. Condor, 80, 138-146.

Amlaner, C.J., & McFarland, D.J. (1981). Sleep in herring gulls (Larus argentatus). Animal Behaviour, 29(2), 551-556.

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Ayala-Guerrero, F., & Vasconcelos-Duenas, I. (1988). Sleep in the dove Zenaida asiatica. Behavioral and Neurological Biology, 49(2), 133-138. Baida, R.P., Morrison, M.L., & Bement, T.R. (1977). Roosting behavior of the pinon jay in autumn and winter. Auk, 94, 494-504. Ball, N.J., Amlaner, C.J., Shaffery, J.P., & Opp, M.R. (1988). Asynchronus eyeclosure and unihemispheric quiet sleep of birds. In W.P. Koella, F. Obal, H. Schulz, & P. Visser (Eds.), Sleep ’86 (pp. 151-153). New York: Gustav Fischer. Ball, N.J., Shaffery, J.P., Opp, M.R., Carter, R.L., & Amlaner, C.J. (1985). Asynchro¬ nous eye-closure of birds [Abstract], Sleep Research, 15, 87.

Ball, N.J., Weaver, G.E., & Amlaner, C.J. (1986). The incidence of hemispheric sleep in birds [Abstract], Sleep Research, 15, 58.

Bartholomew, G. A., & Dawson, W. R. (1979). Thermoregulatory behavior during incuba¬ tion in Heermann’s gulls. Physiological Zo¬ ology, 52, 422-437.


Berger, R. J., & Phillips, N. H. (1994). Constant light suppresses sleep and circadian rhythms in pigeons without consequent sleep re¬ bound in darkness. American Journal of Physiology—Regulatory, Integrative and Comparative Physiology, 267, 945-952. Berger, R.J., Walker, J.M., & Scott, T. D. (1970). Characteristics of sleep in the bur¬ rowing owl and tree shrew [Abstract], Psy¬ chophysiology, 7, 303. Berger, R. J., Walker, J.M., & Scott, T. D. (1972). Sleep in the burrowing owl (Speotyto cunicularia hypugaea). Behavioral Bi¬ ology, 7(2), 183-194. Boerema, A. S, Riedstra, B., & Strijkstra, A. M. (2003). Decrease in monocular sleep after sleep deprivation in the domestic chicken. Behaviour, 140, 1415-1420. Brown, C. R. (1980). Sleeping behavior of pur¬ ple martins. Condor, 82(2), 170-175. Buchet, C., Dewasmes, G., & Le Maho, Y. (1986). An electrophysiological and behav¬ ioral study of sleep in emperor penguins under natural ambient conditions. Physiol¬ ogy & Behavior, 38(3), 331-335. Burish, M.J., Kueh, H.Y., & Wang, S.S.-H. (2004). Brain architecture and social com¬ plexity in modern and ancient birds. Brain, Behavior, & Evolution, 63, 107-124. Calder, W. A. (1975). Daylength and the hum¬ mingbirds use of time. Auk, 92, 81-97. Campbell, S.S. & Tobler, I. (1984). Animal sleep: A review of sleep duration across phylogeny. Neuroscience & Biobehavioral Reviews, 8, 269-300. Carpenter, F.L. (1974). Torpor in an Andean hummingbird: Its ecological significance. Science, 183(4124), 545-547. Catling, P.M. (1972). A behavioral attitude of saw-wheat and boreal owls. Auk, 89, 194-196. Corner, M. A. (1977). Sleep and the beginnings of behavior in the animal kingdom—Studies of ultradian motility cycles in early life. Progress in Neurobiology, 8(4), 279-295.




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Corner, M. A., van Wingerden, C., & Bakhuis, W.L. (1973). Spontaneous motility bursts during sleep in the chick, as related to pha¬ sic “paradoxical” cerebral bioelectric activ¬ ity. Brain Research, 50, 200-204. Dario, A., Lopes, P., Freitas, G.C., Paschoalini, M.A., & Neto, J. M. (1996). Electro¬ graphic patters of postprandial sleep after food deprivation or intraventricular adrena¬ line injections in pigeons. Brain Research Bulletin, 39, 249-254. Derksen, D.V. (1977). A quantitative analy¬ sis of the incubation behavior of the Adelie penguin. Auk, 94, 552-566. Dewasmes, G., Buchet, C., Geloen, A., & Le Maho, Y. (1989). Sleep changes in emperor penguins during fasting. American Jour¬ nal of Physiology—Regulatory, Integrative and Comparative Physiology, 256(2 Pt 2), 476-180. Dewasmes, G., Cohen-Adad, F., Koubi, H., & Le Maho, Y. (1984). Sleep changes in long¬ term fasting geese in relation to lipid and protein metabolism. American Journal of Physiology, 247(4 Pt 2), R663-R671. Dewasmes, G., Cohen-Ada, F., Koubi, H., & Le Maho, Y. (1985). Polygraphic and be¬ havioral study of sleep in geese: Existence of nuchal atonia during paradoxical sleep. Physiology & Behavior, 35(1), 67-73. Dewasmes, G., Cote, S. D., Le Maho, Y., Groscolas, R., Robin, J. P., Vardon, G., et al., (2001). Effects of weather on activity and sleep in brooding king penguins (Aptenodytes patagoincus). Polar Biology, 24(1), 508-511. Dewasmes, G., & Loos, N. (2002). Diurnal sleep depth changes in the king penguin (Aptenodytes patagoincus). Polar Biology, 25(11), 865-867.

Fetterolf, P. M. (1979). Nocturnal behavior of ring-billed gulls during the early incubation period. Canadian Journal of Zoology, 57, 1190-1195. Fuchs, T., Haney, A., Jechura, T.J., Moore, F. R., & Bingman, V.P. (in press). Daytime naps in night-migrating birds: Behavioural adaptation to seasonal sleep deprivation in the Swainson’s thrush, Catharus ustulatus. Animal Behaviour.

Fuchs, T., Siegel, J.J., Burgdorf, J., & Bing¬ man, V.P. (2006). A selective serotonin reuptake inhibitor reduces REM sleep in the homing pigeon. Physiology & Behavior, 87, 575-581. Graf, R., Heller, H. C., Sakaguchi, S., & Krishna, S. (1987). Influence of spinal and hypothalamic warming on metabolism and sleep in pigeons. American Journal of Physiology—Regulatory, Integrative and Comparative Physiology, 225, 661-667. Greenberg, R., Kelty, M., & Dewan, E. (1969). Sleep patterns in the newly hatched chick [Abstract]. Psychophysiology, 6, 226-227. Hamerstrom, F., & Janick, K. (1973). Diurnal sleep rhythm of a young barred owl. Auk, 90, 899-900. Hayward, J. L., Jr., Gillett, W. H., Amlaner, C.J., Jr., & Stout, J.F. (1977). Predation on gulls by bald eagles in Washington. Auk, 94, 375. Hecht, J. (2004). Amazing talent of the bird that doesn’t sleep. New Scientist, 183(1), 10. Hishikawa, Y., Cramer, H., & Kuhlo, W. (1969). Natural and melatonin-induced sleep in young chickens—A behavioral and behavioral and electrographic study. Exper¬ imental Brain Research, 7(1), 84-94.

Dewasmes, G., & Telliez, F. (2000). Tactile arousal threshold of sleeping king penguins in a breeding colony. Journal of Sleep Re¬ search, 9(3), 255-259.

Iwaniuk, A.N., Dean, K.M., & Nelson, J.E. (2005). Interspecific allometry of the brain and brain regions in parrots (Psittaciformes): Comparisons with other birds and primates. Brain, Behavior and Evolution, 65, 40-59.

Dominguez, J. (2003). Sleeping and vigilance in black-tailed godwit. Journal of Ethology, 21, 57-60.

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Guitterres-Rivas, E. (1980). El ciclo vigiliasueno del gato I. Estudio con diferentes condiciones de experiementacion. Arch Neurobiol (Madr), 43, 185-200. Hartmann, E., Bernstein, J., & Wilson, C. (1968). Sleep and dreaming in the elephant [Abstract], Psychophysiology, 4, 389. Haskell, E. H., Walker, J. M., & Berger, R.J. (1979). Effects of cold stress on sleep of an hibernator, the golden-mantled ground squirrel (C. lateralis). Physiology & Behav¬ ior 23(6), 1119-1121.

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745-752. Sazonov, V. S. (1981). Influence of the low environmental temperatures on wakeful¬ ness-sleep periodicity in the lemming. Journal of Evolutionary Biochemistry and Physiology, 17(4), 259-262.

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Strijkstra, A.M., & Daan, S. (1997). Ambient temperature during torpor affects NREM sleep EEG during arousal episodes in hiber¬ nating European ground squirrels. Neuro¬ science Letters, 221(2-3), 177-180.

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Sunquist, M., & Montgomery, G. (1973). Ac¬ tivity patterns and rates of movement of two-toed and three-toed sloths, Choloepus hoffmani and Bradypus infuscatus. Journal of Mammalogy, 54, 946-954. Susie, V., & Masirevic, G. (1986). Sleep pat¬ terns in the Mongolian gerbil (Meriones unguilculatus). Physiology & Behavior, 37, 257-261. Swett, C. (1969). Daytime sleep patterns in free-ranging Rhesus Monkeys [Abstract]. Psychophysiology, 6, 227. Takahashi, Y., Hoinhara, S., Nakamura, Y., & Takahashi, K. (1981). A model of human sleep-related growth hormone secretion in dogs: Effects of 3, 6, and 12 hours of wake¬ fulness on plasma growth hormone, cortisol, and sleep stages. Endocrinology, 109(1), 262-272. Tang, X., & Sanford, L.D. (2002). Telemetric recording of sleep and home cage activity in mice. Sleep, 25(6), 691-699.

Tobler, I., & Schwierin, B. (1996). Behavioural sleep in the giraffe (Giraffa Camelopardalis) in a zoological garden. Journal of Sleep Re¬ search, 5(1), 21-32. Toutain, P. L., & Ruckebusch, Y. (1975). Arousal as a cyclic phenomenon during sleep and hibernation in the hedgehog (Erinaceus europaeus). Experientia, 31, 312-314. Ursin, R. (1968). The 2 stages of slow-wave sleep in the cat and their relation to REM sleep. Brain Research, 11, 347-356. Valatx, J. L., & Bugat, R. (1974). [Genetic fac¬ tors as determinants of the waking-sleep cycle in the mouse (author’s transl)]. Brain Research, 69(2), 315-330. Van Twyver, H. (1969). Sleep patterns in five rodent species. Physiology & Behavior, 4, 901-905. Van Twyver, H., & Allison, T. (1970). Sleep in the opossum Didelphis marsupialis. Elec¬ troencephalography and Clinical Neuro¬ physiology, 29(2), 181-189.

Tauber, E. S., Michel, F., & Roffwarg, H.P. (1968). Preliminary note on the sleep and waking cycle in the desert hedgehog (Paraechinus hypomalas) [Abstract]. Psycho¬ physiology, 5, 201.

Van Twyver, H., & Allison, T. (1974). Sleep in the armadillo Dasypus novemcinctus at moderate and low ambient tempera¬ tures. Brain, Behavior and Evolution, 9(2), 107-120.

Tenaza, R., Ross, B.A., Tanticharoenyos, P., & Berkson, G. (1969). Individual behaviour and activity rhythms of captive slow lorises (Nycticebus coucang). Animal Behavior, 17, 664-669.

Walker, J. M., Glotzbach, S. F., Berger, R. J., & Heller, H.C. (1977). Sleep and hibernation in ground squirrels (Citellus spp): Electrophysiological observations. American Jour¬ nal of Physiology—Regulatory, Integrative

Tobler, I. (1992). Behavioral sleep in the Asian elephant in captivity. Sleep, 15(1), 1-12. Tobler, I., & Deboer, T. (2001). Sleep in the blind mole rat Spalax ehrenbergi. Sleep, 24(2), 147-154. Tobler, I., Franken, P., & Scherschlicht, R. (1990). Sleep and EEG spectra in the rab¬ bit under baseline conditions and following sleep deprivation. Physiology & Behavior, 48, 121-129. Tobler, I., & Jaggi, K. (1987). Sleep and EEG spectra in the Syrian hamster (Mesocricetus auratus) under baseline conditions and fol¬ lowing sleep deprivation. Journal of Com¬ parative Physiology A, 161(3), 449-459.





R213-R221. Walker, J.M., Walker, L. E., Harris, D. V., & Berger, R.J. (1983). Cessation of thermo¬ regulation during REM sleep in the pocket mouse. American Journal of Physiology, 244(\), R114-R118. Wauquier, A., Verheyen, J. L., van den Broeck, W.A., & Janssen, P. A. (1979). Visual and computer-based analysis of 24 h sleep¬ waking patterns in the dog. Electroenceph¬ alography and Clinical Neurophysiology, 46(1), 33-48.

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Appendix: Additional Resources on Sleep

sleep of Macaca mulatto.. Archives of Neu¬ rology, 12, 463^467. Wexler, D.B., & Moore-Ede, M.C. (1985). Circadian sleep-wake cycle organization in squirrel monkeys. American Journal of Physiology—Regulatory, Integrative and Comparative Physiology, 248, R353-R362. Zepelin, H. (1970). Sleep of the jaguar and the tapir: A prey-predator contrast [Abstract], Psychophysiology, 7, 305-306. Zepelin, H. (1989). Mammalian sleep. In M. H. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practices of sleep medicine

(pp. 81-92). Philadelphia: Saunders. Zepelin, H., & Rechtschaffen, A. (1974). Mam¬ malian sleep, longevity, and energy metabo¬ lism. Brain, Behavior and Evolution, 70(6), 425-470. Zolovick, A., Stern, W., Jalowiec, J., Panksepp, J., &Morgane, P. (1973). Sleep-waking pat¬ terns in cats: Effects of 6-hydroxy dopamine given into the dorso-lateral pontine tegmen¬ tum [Abstract], Sleep Research, 2, 74.

Mammal Articles with REM Density Data Balzamo, E., Bradley, R.J., & Rhodes, J.M. (1972). Sleep ontogeny in the chimpan¬ zee: From two months to forty-one months. Electroencephalography and Clinical Neu¬ rophysiology, 33, 47-60.

Bert, J., & Collomb, H. (1966). L’electroencephalogramme du sommeil nocturne chez le babouin. Etude par telemetrie. J Physiol (Parris), 58, 285-301.

Mammal Papers with Arousal Activity Data Affanni, J.M., Cervino, C.O., & Marcos, H.J.A. (2001). Absence of penile erections during paradoxical sleep: Peculiar penile events during wakefulness and slow wave sleep in the armadillo. Journal of Sleep Re¬ search, 10, 219-228.


Allison, T., Van Twyver, H., & Goff, W.R. (1972). Electrophysiological studies of the echidna, Tachyglossus aculeatus, I: Wak¬ ing and sleep. Comparative Biochemistry and Physiology Part A: Molecular & Inte¬ grative Physiology, 110, 145-184.

Berger, R.J., & Walker, J.M. (1972). A poly¬ graphic study of sleep in the tree shrew (Tupaia glis). Brain, Behavior and Evolution, 5(1), 54-69. Carskadon, M.A., & Dement, W.C. (2006). Normal human sleep: An overview. In M. H. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practice of sleep medicine

(4th ed„ pp. 13-23). Philadelphia: WB Saunders. Dallaire, A., & Ruckebusch, Y. (1974). Sleep and wakefulness in the housed pony under different dietary conditions. Canadian Jour¬ nal of Comparative Medicine, 38, 65-71. Hunter, J. D., & Milson, W. K. (1998). Corti¬ cal activation states in sleep and anesthesia. I: Cardio-respiratory effects. Respiratory Physiology, 772(1), 71-81. Immelman, K., & Gebbing, H. (1962). Schlaf bei Giraffiden. Z Tierpsychol, 19, 84-92. Kaemingk, K., & Reite, M. (1987). Social en¬ vironment and nocturnal sleep: Studies in peer-reared monkeys. Sleep, 10, 542-550. Ridgway, S.H., Harrison, R.J., & Joyce, P. L. (1975). Sleep and cardiac rhythm in the gray seal. Science, 187(4116), 553-555. Ruckebusch, Y. (1972). The relevance of drowsiness in the circadian cycle of farm animals. Animal Behavior, 20(4), 637-643. Sazonov, V. S. (1981). Influence of the low en¬ vironmental temperatures on wakefulnesssleep periodicity in the lemming. Journal of Evolutionary Biochemistry and Physiology,

77(4), 259-262. Strijkstra, A.M., & Daan, S. (1997). Ambient temperature during torpor affects NREM sleep EEG during arousal episodes in hiber¬ nating European ground squirrels. Neuro¬ science Letters, 227(2-3), 177-180. Tenaza, R., Ross, B.A., Tanticharoenyos, P., & Berkson, G. (1969). Individual behaviour




Appendix: Additional Resources on Sleep

and activity rhythms of captive slow lorises (Nycticebus coucang). Animal Behavior, 17, 664-669. Van Twyver, H., & Allison, T. (1970). Sleep in the opossum Didelphis marsupialis. Elec¬ troencephalography and Clinical Neuro¬ physiology, 29(2), 181-189.

Walker, J.M., Glotzbach, S.F., Berger, R.J., & Heller, H.C. (1977). Sleep and hiber¬ nation in ground squirrels (Citellus spp): Electrophysiological observations. Ameri¬ can Journal of Physiology—Regulatory, Integrative and Comparative Physiology, 233(5), R213-R221.

Mammal Sleep Papers with Spindling Data Adams, P., & Barratt, E. (1974). Nocturnal sleep in squirrel monkeys. Electroencepha¬ lography & Clinical Neurophysiology, 36,

201-204. Affani, J. (1972). Observations on the sleep of some South American marsupials and edenates. Persped Brain Sci, 1, 21-23. Affanni, J.M., Cervino, C.O., & Marcos, H.J.A. (2001). Absence of penile erections during paradoxical sleep. Peculiar Journal of Sleep Research. Penile events during wakefulness and slow wave sleep in the ar¬ madillo, 10, 219-228. Allison, T., Gerber, S.D., Breedlove, S.M., & Dryden, G.L. (1977). A behavioral and polygraphic study of sleep in the shrews Suncus murinus, Blarina brevicauda, and Cryptotis parva. Behavioral Biology, 20(3), 354-366.

Ambrosini, M. V., Gambelunghe, C., Mariucci, G., Bruschelli, G., Adami, M., & Guiditta, A. (1994). Sleep-wake variables and EEG power spectra in Mongolian gerbils and Wistar rats. Physiology & Behavior, 56(5), 963-968. Ayala-Guerrero, F., Vargas-Reyna, L., Ramos, J.F, & Mexicano, G. (1998). Sleep patterns of the volcano mouse (Neotomodon alstoni alstoni). Physiology & Behavior, 64(A), 577-580. Balzamo, E. (1973). Etude des etats de vigi¬ lance chez Papio cynocephalus adulte. C R Seances Soc Biol, 167, 1168-1172. Balzamo, E., & Bert, J. (1975). Sleep in Papio anubis: Its organization and lateral genicu¬ late spikes [Abstract]. Sleep Research, 4, 138. Balzamo, E., Bradley, R.J., & Rhodes, J.M. (1972). Sleep ontogeny in the chimpan¬ zee: From two months to forty-one months. Electroencephalography and Clinical Neu¬ rophysiology, 33, 47-60.

Balzamo, E., Vuillon-Cacciuttolo, G., & Bert, J. (1978). Cercopithecus aethiops: EEG et organization des etats de vigiliance. Wake Sleep, 2, 223-230. Balzamo, E., Vuillon-Cacciuttolo, G., Petter, J., & Bert, J. (1978). Etats de vigiliance chez deux Lemuridae: Rhythmes EEG et organi¬ zation obtenus par telemesure. Wake Sleep, 2, 237-245. Barre, V., & Petter-Rousseaux, A. (1988). Seasonal variations in sleep-wake cycle in Microcebus murinus. Primates, 19(2), 53-64.

Allison, T., & Van Twyver, H. (1970). Sleep in the moles, Scalopus aquaticus and Condylura cristata. Experimental Neurology, 27(3), 564-578.

Batini, C., Radulovacki, M., Kado, R.T., & Adey, W.R. (1967). Effect of interhemispheric transection on the EEG patterns in sleep and wakefulness in monkeys. Electro¬

Allison, T., Van Twyver, H., & Goff, W. R. (1972). Electrophysiological studies of the echidna, Tachyglossus aculeatus, I: Wak¬ ing and sleep. Comparative Biochemistry

encephalography and Clinical Neurophysi¬

and Physiology Part A: Molecular & Inte¬ grative Physiology, 110, 145-184.

ology, 22, 101-112.

Bell, F. R., & Itabisashi, T. (1973). The elec¬ troencephalogram of sheep and goats with special reference to rumination. Physiology & Behavior, 11, 503-514.

Appendix: Additional Resources on Sleep

Berger, R.J., & Walker, J.M. (1972). A poly¬ graphic study of sleep in the tree shrew (Tupaia glis). Brain, Behavior and Evolution, 5(1), 54-69. Bert, J., Balzamo, E., Chase, M., & Pegram, V. (1975). The sleep of the baboon, Papio papio, under natural conditions and in the laboratory. Electroencephalography and Clinical Neurophysiology, 39, 657-662.


Crowley, T.J., Kripke, D.F., Halberg, F., Pe¬ gram, G. V., & Schildkraut, J. J. (1972). Cir¬ cadian rhythms of Macaca mulatto: Sleep, EEG, body and eye movement, and temper¬ ature. Primates, 13, 149-168. Dallaire, A., & Ruckebusch, Y. (1974). Restactivity cycle and sleep patterns in captive foxes (Vulpes Vulpes). Experientia, 30, 59-60.

Bert, J., Collomb, H., & Martino, A. (1967). L’electroencephalogramme du sommeil d’un prosimien. Sa place dans V organisation du sommeil chez les primates. Electroen¬

Dallaire, A., & Ruckebusch, Y. (1974). Sleep and wakefulness in the housed pony under different dietary conditions. Canadian Jour¬ nal of Comparative Medicine, 38, 65-71.

cephalography and Clinical Neurophysiol¬

Deboer, T., & Tobler, I. (1996). Shortening of the photoperiod affects sleep distribution, EEG and cortical temperature in the Djungarian hamster. Journal of Comparative Physiology A, 179(4), 483-492.

ogy, 23, 342-350.

Bert, J., Kripke, D. F., & Rhodes, J. (1970). Elec¬ troencephalogram of the mature chimpanzee: Twenty-four hour recordings. Electroen¬ cephalography and Clinical Neurophysiol¬ ogy, 28, 32-40.

Bert, J., & Pegram, V. (1969). L’electroence¬ phalogramme du sommeil chez les Cercopithecinae: Erythrocebus patas et Cerpothiecus aethiops





151-159. Bert, J., Pegram, V., Rhodes, J. M., et al. (1970). A comparative sleep study of two cercopithecinae. Electroencephalography and Clini¬ cal Neurophysiology, 28(1), 32^40.

Galvao de Moura Filho, A. G., Huggins, S.E., & Lines, S.G. (1983). Sleep and waking in the three-toed sloth, Bradypus tridactylus. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiol¬ ogy, 76(2), 345-355.

Gonzalez, F. F., Zaplana, J., Ruiz de Elvira, C., & Delgado, J.M. (1979). Nocturnal and diurnal sleep in Macaca sylvana. Electro¬ encephalography and Clinical Neurophysi¬ ology, 46(1), 13-28.

Breton, P., Gourmelon, P., & Court, L. (1986). New findings on sleep stage organization in squirrel monkeys. Electroencephalogra¬

Leinonen, L., & Stenberg, D. (1986). Sleep in Macaca arctoides and the effects of prazosin. Physiology & Behavior, 37(2), 199-202.

phy and Clinical Neurophysiology, 40(6),

Lucas, E.A. (1979). Effects of a short lightdark cycle on the sleep-wake patterns of the cat. Sleep, 7(3), 299-317.

563-567. Carskadon, M.A., & Dement, W.C. (2006). Normal human sleep: An overview. In M. H. Kryger, T. Roth, & W.C. Dement (Eds.), Principles and practice of sleep medicine

(4th ed., pp. 13-23). Philadelphia: WB Saunders. Crofts, H. S., Wilson, S.,Muggleton,N. G.,Nutt, D. J., Scott, E. A., & Pearce, P.C. (2001). In¬ vestigation of the sleep electrocorticogram of the common marmoset (Callithrix jacchus) using radiotelemetry. Clinical Neuro¬ physiology, 772(12), 2265-2213.

Lucas, E. A., Powell, E. W., & Murphree, O. D. (1977). Baseline sleep-wake patterns in the pointer dog. Physiology & Behavior, 19, 285-291. Lucas, E.A., & Sterman, M.B. (1974). The polycyclic sleep-wake cycle in the cat: Ef¬ fects produced by sensorimotor rhythm conditioning. Experimental Neurology, 42, 347-368. Lyamin, O.I., & Chetyrbok, I.S. (1992). Uni¬ lateral EEG activation during sleep in the




Appendix: Additional Resources on Sleep

Cape fur seal, Arctocephalus pusillus. Neu¬ roscience Letters, 143(1-2), 263-266.

correlates. Physiology & Behavior, 245-251.


Lyamin, O. I., Mukhametov, L. M., Chetyrbok, I. S., & Vassiliev, A.V. (2002C). Sleep and wakefulness in the southern sea lion. Behav¬ ioural Brain Research, 128, 129-138.

Ruckebusch, Y„ & Bell, F.R. (1970). Etude polygraphique et comportementale es etats dev veille et de sommeil chez la vache (Bos taurus). Ann Rech Vet, 1, 41-62.

Marks, G. A., & Shaffery, J.P. (1996). A pre¬ liminary study of sleep in the ferret, Mustela putorius furo: A carnivore with an extremely high proportion of REM sleep. Sleep, 19(2), 83-93.

Sterman, M.B., Knauss, T., Lehmann, D., & Clemente, C. D. (1965). Circadian sleep and waking patterns in the laboratory cat. Elec¬

McNew, J.J., Howe, R.C., & Adey, W.R. (1971). The sleep cycle and subcorticalcortical EEG relations to the unrestrained chimpanzee. Electroencephalography and Clinical Neurophysiology, 30(6), 489-503.

Sunquist, M., & Montgomery, G. (1973). Ac¬ tivity patterns and rates of movement of two-toed and three-toed sloths, Choloepus hoffmani and Bradypus infuscatus. Journal of Mammalogy, 54, 946-954.

Nicol, S. C., Andersen, N. A., Phillips, N. H., & Berger, R. J. (2000). The echidna manifests typical characteristics of rapid eye move¬ ment sleep. Neuroscience Letters, 283(1), 49-52.

Susie, V., & Masirevic, G. (1986). Sleep pat¬ terns in the Mongolian gerbil (Meriones unguilculatus). Physiology & Behavior, 37, 257-261.

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275-282. Reite, M. L., Rhodes, J. M., Kavan, E., & Adey, W.R. (1965). Normal sleep patterns in Ma¬ caque monkey. Archives of Neurology, 12, 133-144. Reite, M., & Short, R. (1985). Behavior and physiology in young bonnet monkeys. Developmental



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troencephalography & Clinical Neurophys¬ iology, 19, 509-517.

Tobler, I., & Deboer, T. (2001). Sleep in the blind mole rat Spalax ehrenbergi. Sleep, 24(2), 147-154. Toutain, P. L., & Ruckebusch, Y. (1975). Arousal as a cyclic phenomenon during sleep and hibernation in the hedgehog (Erinaceus europaeus). Experientia, 31, 312-314. Ursin, R. (1968). The 2 stages of slow-wave sleep in the cat and their relation to REM sleep. Brain Research, 11, 347-356. Valatx, J.L., & Bugat, R. (1974). [Genetic fac¬ tors as determinants of the waking-sleep cycle in the mouse]. Brain Research, 69(2), 315-330. Van Twyver, H., & Allison, T. (1970). Sleep in the opossum Didelphis marsupialis. Elec¬ troencephalography and Clinical Neuro¬ physiology, 29(2), 181-189.

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Appendix: Additional Resources on Sleep

Electrophysiological observations. Ameri¬ can Journal of Physiology—Regulatory, Integrative and Comparative Physiology, 233(5), R213-R221.

Wauquier, A., Verheyen, J. L., van den Broeck, W. A., & Janssen, P. A. (1979). Visual and computer-based analysis of 24 h sleep¬ waking patterns in the dog. Electroenceph¬ alography and Clinical Neurophysiology,

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Mammal Papers with Duration of Stages 3 and 4 of NREM or SlowWave Activity Adams, P., & Barratt, E. (1974). Nocturnal sleep in squirrel monkeys. Electroencepha¬ lography & Clinical Neurophysiology, 36,

201-204. Balzamo, E. (1973). Etude des etats de vigi¬ lance chez Papio cynocephalus adulte. C R Seances Soc Biol, 167, 1168-1172. Balzamo, E., & Bert, J. (1975). Sleep in Papio anubis: Its organization and lateral genicu¬ late spikes [Abstract], Sleep Research, 4, 138. Balzamo, E., Bradley, R. J., & Rhodes, J.M. (1972). Sleep ontogeny in the chimpan¬ zee: From two months to forty-one months. Electroencephalography and Clinical Neu¬ rophysiology, 33, 47-60.

Balzamo, E., Vuillon-Cacciuttolo, G., & Bert, J. (1978). Cercopithecus aethiops: EEG et organization des etats de vigiliance. Wake Sleep, 2, 223^230.

Balzamo, E., Vuillon-Cacciuttolo, G., Petter, J., & Bert, J. (1978). Etats de vigiliance chez


deux Lemuridae: Rhythmes EEG et organi¬ zation obtenus par telemesure. Wake Sleep, 2, 237-245. Batini, C., Radulovacki, M., Kado, R.T., & Adey, W. R. (1967). Effect of interhemispheric transection on the EEG patterns in sleep and wakefulness in monkeys. Electro¬ encephalography and Clinical Neurophysi¬ ology, 22, 101-112.

Berger, R.J., & Walker, J.M. (1972). A poly¬ graphic study of sleep in the tree shrew (Tupaia glis). Brain, Behavior and Evolution, 5(1), 54-69. Bert, J. (1970). Adaptation du sommeil aux conditions experimentales d’enregistrement chez deux Cercopithecinae (Papio papio et Macaca radiata). Proceeding of the 3rd Inter¬ national Congress in Primatology, 2, 49-53. Bert, J. (1973). Similitudes et differences du sommeil chez deux babouins, Papio hamadryas et Papio papio. Electroencephalogra¬ phy and Clinical Neurophysiology, 35(2),

209-212. Bert, J., Balzamo, E., Chase, M., & Pegram, V. (1975). The sleep of the baboon, Papio papio, under natural conditions and in the laboratory. Electroencephalography and Clinical Neurophysiology, 39, 657-662. Bert, J., Collomb, H., & Martino, A. (1967). L’electroencephalogramme du sommeil d’un prosimien. Sa place dans l’organisation du sommeil chez les primates. Electroen¬ cephalography and Clinical Neurophysiol¬ ogy, 23, 342-350.

Bert, J., Kripke, D.F., & Rhodes, J. (1970). Elec¬ troencephalogram of the mature chimpanzee: Twenty-four hour recordings. Electroen¬ cephalography and Clinical Neurophysiol¬ ogy, 28, 32—40.

Bert, J., & Pegram, V. (1969). L’electroencep¬ halogramme du sommeil chez les Cercopith¬ ecinae: Erythrocebus patas et Cerpothiecus aethiops





151-159. Bert, J., Pegram, V., & Balzano, E. (1972). Comparison du sommeil de deux macaques




Appendix: Additional Resources on Sleep

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Bert, J., Pegram, V., Rhodes, J.M., Balzano, E. , & Naquet, R. (1970). A comparative sleep study of two cercopithecinae. Electro¬ encephalography and Clinical Neurophysi¬ ology, 28(1), 32^40.

Breton, P., Gourmelon, P., & Court, L. (1986). New findings on sleep stage organization in squirrel monkeys. Electroencephalogra¬ phy and Clinical Neurophysiology, 40(6),

563-567. Crofts, H.S., Wilson, S., Muggleton, N. G., Nutt, D.J., Scott, E.A., & Pearce, P.C. (2001). Investigation of the sleep electrocorticogram of the common marmoset (Callithrix jacchus) using radiotelemetry. Clinical Neurophysiology, 112(12), 2265-2213.

Crowley, T.J., Kripke, D. F., Halberg, F., Pe¬ gram, G. V., & Schildkraut, J. J. (1972). Cir¬ cadian rhythms of Macaca mulatta: Sleep, EEG, body and eye movement, and temper¬ ature. Primates, 13, 149-168. Freemon, F. R., McNew, J.J., & Adey, W.R. (1971). Chimpanzee sleep stages. Electro¬ encephalography and Clinical Neurophysi¬ ology, 31, 485-489.

Galvao de Moura Filho, A.G., Huggins, S.E., & Fines, S.G. (1983). Sleep and waking in the three-toed sloth, Bradypus tridactylus. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiol¬ ogy, 76(2), 345-355.

Hunter, J.D., & Milson, W.K. (1998). Corti¬ cal activation states in sleep and anesthesia. I: Cardio-respiratory effects. Respiratory Physiology, 772(1), 71-81. Immelman, K., & Gebbing, H. (1962). Schlaf bei Giraffiden. Z Tierpsychol, 19, 84-92. Kaemingk, K., & Reite, M. (1987). Social environment and nocturnal sleep: Stud¬ ies in peer-reared monkeys. Sleep, 10, 542-550. Karmanova, I. G., Maksimuk, F. M., Murav’ eva, F. N., Pastukhov, Y.F., & Sazonov, V.S. (1979). [Specific features of the cycle “wakefulness-sleep” in the arctic lemming

Dicrostonyx torquats] (in Russian). Zh Evol Biokim Fiziol, 15, 190-195. Feinonen, F., & Stenberg, D. (1986). Sleep in Macaca arctoides and the effects of prazosin. Physiology & Behavior, 37(2), 199-202. Fyamin, O.I., & Chetyrbok, I. S. (1992). Uni¬ lateral EEG activation during sleep in the Cape fur seal, Arctocephalus pusillus. Neu¬ roscience Letters, 143(1-2), 263-266. Fyamin, O. I., Mukhametov, F. M., Chetyrbok, I.S., & Vassiliev, A.V. (1994). Sleep and wakefulness in southern sea lions (Otari byronia). Journal of Sleep Research, 3(Suppl. 1), 152. Fyamin, O. I., Mukhametov, F. M., Chetyrbok, I.S., & Vassiliev, A.V. (2002). Sleep and wakefulness in the southern sea lion. Behav¬ ioural Brain Research, 128, 129-138. Fyamin, O.I., Oleksenko, A. I., & Sevostiyanov, V.F. (2000). Behavioral sleep in captive sea otters. Aquatic Mammals, 26, 132-136. McNew, J.J., Howe, R.C., & Adey, W.R. (1971). The sleep cycle and subcorticalcortical EEG relations to the unrestrained chimpanzee. Electroencephalography and Clinical Neurophysiology, 30(6), 489-503. Miller, V.M., & South, F.E. (1981). Entry into hibernation in M. flaviventris: Sleep and behavioral thermoregulation. Physiology & Behavior, 27(6), 989-993. Mukhametov, F.M., Fyamin, O.I., & Polyakova, I.G. (1985). Interhemispheric asynchrony of the sleep EEG in northern fur seals. Experientia, 47(8), 1034—1035. Mukhametov, L. M., Supin, A. Y., & Polyakova, I.G. (1977). Interhemispheric asymmetry of the electroencephalographic sleep pat¬ terns in dolphins. Brain Research, 134(3), 581-584. Nicol, S.C., Andersen, N.A., Phillips, N.H., & Berger, R.J. (2000). The echidna manifests typical characteristics of rapid eye movement sleep. Neuroscience Letters, 283(1), 49-52. Nishino, S., Riehl, J., Hong, J., Kwan, M., Reid, M., & Mignot, E. (2000). Is narcolepsy a REM sleep disorder? Analysis of sleep

Appendix: Additional Resources on Sleep

abnormalities in narcoleptic dobermans. Neuroscience Research, 38, 437-446. Palchykova, S., Deboer, T., & Tobler, I. (2002). Selective sleep deprivation after daily torpor in the Djungarian hamster. Journal of Sleep Research, 11, 313-319. Pivik, R.T., Bylsma, F.W., & Cooper, P. (1986). Sleep-wakefulness rhythms in the rabbit. Behavioral and Neural Biology, 45(3), 275-286. Reite, M. L., Rhodes, J. M., Kavan, E., & Adey, W. R. (1965). Normal sleep patterns in Ma¬ caque monkey. Archives of Neurology, 12, 133-144. Reite, M., Stynes, A.J., Vaughn, L., Pauley, J. D., & Short, R.A. (1976). Sleep in in¬ fant monkeys: Normal values and behav¬ ioral correlates. Physiology & Behavior, 16, 245-251. Robinson, E. L., Hsieh, J. K., & Fuller, C.A. (2003). A primate model of sleep regulation [Abstract], Sleep, 2 The Bible and dreams: Church dream groups, 123-24; Luther and Calvin, 78-80; Middle Ages and dreams, 423; poetry and dreams, 508; stories about dreams, 123; theater and dreams, 739


Bidart, Frank, 510

Born, J., 791

The Big Dream Interpretation Book (Taf-

Bosnak, Robert, 244, 393

seer Al-ahlam Al-kabir) (Ibn Sirin), 75

Big dreams, 81-82, 344, 374, 378, 390, 392-93. See also Little dreams Bion, Wilfred, 314


Botz-Borstein, 197 Boulware, L. E., 201 Boundary Questionnaire, 133 Boys: animal figures in dreams, 37;

Birds: NREM sleep patterns, 498

dream content compared with girls, 14,

Bird sleep studies, 153, 154, 169-71,

115; themes of dreams, 115


Brain, sleep, and dreams: adult new nerve

Bird songs, and sleep, 596-97

cell generation, 627-29; basis of dream

Bishop, Bridget, 353

consciousness, 159-60; and basis of

Bizarre imagery and thought in sleep and

dream consciousness, 159-60; blind¬

waking (IT), 82-84 Bizarreness of dreams, for video game players, 795, 798

ness effects on sleep and dreams, 239; and blindness effects on sleep and dreams, 239; circadian rhythmicity,

Black Dog (De Vere), 39-40

131-32; and circadian rhythmicity,

Blagrove, M., 233, 234

131-32; colors in dreams, 144-45; and

Blake, H„ 154, 209

colors in dreams, 144-45; and comics

Blake, William, 182, 196, 390

reading, 311; default mode network,

Bless me, Ultima (Anaya), 391

598-602; and detailed focal vision,

Blindness, effects on dream content of

615-17; disconnection from external

deafness and, 238-40

environment during dreaming, 206-7;

Bly, Robert, 509-10

dream-lag/day-residue effects, 228;

BMI (body mass index): and sleep dura¬

fetal development and yawning, 282;

tion studies, 619-20, 631; and sleepi¬

and handedness, 320-22; hypnago¬

ness in teens, 644. See also Obesity,

gic dream state, 328; and hypnagogic

and sleep

dream state, 328; illusory content in

Body dreamwork, 84-89; dream story/

dreams, 342-43; and illusory content

continuation, 89; new energy require¬

in dreams, 342-43; neuropsychology

ments, 86; obtaining help from the

of lost dream recall, 458; noninvasive

dream, 86-87; sources of questions,

research techniques, 790; olfactory

86; working with dream characters,

stimuli and dreams, 471-73; PGO cor¬


tical spikes of REM sleep, 83; poste¬

Bokert, E., 66

rior cingulate cortex, 294, 452, 559,

Book of the Duchess (Chaucer), 508

598-99; prefrontal cortex in dream¬

Boot, W. R„ 795

ing, 91-92, 446-47, 513-17; regula¬

Borbeley, Alexander, 154

tion of sleep, 45; research of Antrobus,

Borderline personality disorder (BPD),

52; role of subcortical structures in

607, 693

dreaming, 562-63; and SWS genera¬

Borg, Isak, 128

tion, 212-13; yawning mechanisms,

Borges, Jorge Luis, 279, 390

809-10. See also Acetylcholine;





EEG measures; Neural metaphor and

Brink, T. L., 284

dreams; Neuroanatomical correlates

Brinton, Howard, 528

of dream censorship; Neuroanatomi¬

Bronte, Emily, 390

cal correlates of dreamwork; Neuro¬

Broughton, James, 130

anatomy of REM sleep and depression;

Brown, Michael, 191

Neurobiology of psychoanalysis in

Brunt, L„ 188-89

wake and REM sleep; NREM (non¬

Bruvel, Gil, 182

rapid eye movement) sleep; Phasic

Buchignani, C., 164

ponto-geniculo-occipital/pontine wave;

Buddhism: Buddhist-oriented dreams,

REM (rapid eye movement) sleep;

801; dream groups, 123-24

Sleep, dreams, and personality; Sleep

Bunuel, Luis, 129, 130, 197

and the generation of new nerve cells

Burne-Jones, Edward, 182

in the adult brain

Burton, Tim, 39

Brain correlates to lucidity, 90-92, 398

Burwell, C. S„ 101

Brain damage, effects on dreams, 93-95 Brain energy, metabolism, and sleep, 95-97 Brain imaging techniques: as comple¬

Caffeine: and adolescent consumption, 660; benefits and use of, 11; and de¬ creased sleep, 96; and sleep interfer¬

mentary assessment method, 72; de¬

ence, 347; and university students

velopment of, 8; for lucid dreaming

usage, 695; vs. prophylactic naps, 10

assessment, 91; by positron emission

Calder, Alexander, 197

tomography (PET), 96. See also Com¬

Callen, F„ 234

puted tomography; Functional mag¬

Calvin, John, 78-80; attitude towards

netic resonance imaging; Functional

dreams, 79-80; theological points of,

neuroimaging during human sleep;

79-80. See also The Bible and dreams

Positron emission tomography; Single¬

Cancer patients and dreamwork, 105-9;

photon emission computed tomography

dream reentry technique, 107-8; ef¬

Brain-injured patients (BIPs), 670-71

fects of healing dreams, 108-9; goals/

Brain mechanisms of vision in dreams,

projective approach, 107; healing


dreams, 106-7; healing imagery, 107,

Brain networks and sleep, 597-602

325; integrative approach, 105-6; out¬

Brain tumors, 667, 669

comes, 108; and Qi Gong, 105; use of

Brakhage, Stan, 125, 130

guided imagery CDs, 107-8

Brandt, Bill, 494 Brazilian dream reports, 186, 348

The Canterbury Tales (Chaucer), 391,


Brazilian studies, 348

Cardiometabolic risk, and sleep, 602-3

Breastfeeding (effects on infant sleep),

Cardiometabolic risk and sleep, 602-3

174-78, 354-55 Brenneis, C. B., 806

Cardiorespiratory polysomnography, 71-72

Brilmayer, H., 209

Cardiovascular disease (CVD), 201; and

Brine, Katherine, 96

depression, 201; and effects of work



on sleep, 241; inflammation, and sleep,

nightmare analysis, 462; self-

683-85; and napping relationship, 434;

assessment tools of Circadian typology,

and OS A, 167-68; and sleep apnea,

572-73; sleep and nap patterns, 46;

529, 638, 684-85; and sleep defi¬

television viewing, 411

ciencies, 602-3. See also Metabolic syndrome

Children’s dreams and nightmares, 114-19; common themes, 115-16;

Carroll, Lewis, 279

dream development, 134; Dream¬

Carroll, Noel, 126

ing publication, 226; effect of divorce

Carta, Stefano, 431

on, 116-17; and illusory contents in

Cash, Johnny, 431

dreams, 343-44; imaginary rescript¬

Casto Spirituality Scoring System, 187

ing method, 118; night terrors, 117;

The Catalogue of Phenomenon of

posttraumatic nightmares, 117-18; and

Dreams, as Connecting Sleeping and

Sigmund Freud’s work, 291; studies of

Waking (Shelley, P. B.), 183

dreams, 139

Caton, R., 100

Children with cancer and sleep, 666-69

Cats: and brain lesions, 101; dream con¬

China: dream beliefs, 55; hallucinations

tent studies, 213; in metabolic tests,

in sleep paralysis, 64; polyphasic sleep

96; phasic twitching, 170; REM sleep

culture in, 189

research on, 209; in subject’s dreams,

Chinese sex symbols in dreams, 119-21


Chouinard, S., 607

Cats, research on REM sleep, 209

Christianity/Christian Church: dream

The Cat with Hands (Morgan), 40

groups, 123-24; and erotic dreams,

Cayce, Edgar, 350

352; European art representations, 801;

Cell phone use: adolescents and sleep,

Luther, Calvin, the Bible and dreams,

12-13; and sleep, 411-12 Central image (Cl) of the dream, 109-10, 161-62 Central sleep apnea (CSA), 636, 649 Chaos in dreams, self-organization from, 577-78 Characters in dreams, 110-13

78-80 Christman, S. D., 321, 322 A Christmas Carol, 128

Chronic kidney disease and sleep disor¬ ders, 201-2, 528-30, 647-48 Chronic renal failure, insomnia in, 357-58

Chaucer, Geoffrey, 391, 508

Chronotype, 121-22, 573

Chenier, V., 322

Church dream groups, 123-24

Cheyne, Allan, 367

Cinema and dreams, 124-31; dream-film

Child, Charles, 185

analogy theory, 125-26; dream inter¬

Children and sleep: ADHD and dreaming,

pretation plots, 130; dream journey

62-63; and bedtime, 15-16; cell phone

plots, 128-29; film as dream represen¬

use, 411-12; and co-sleeping, 174-78;

tations, 124-25; horror and nightmare

importance oj7 sleep health for, 346-47;

plots, 129-30; metaphysical fantasy

melatonin therapy for sleep disor¬

plots, 129; surrealist films, 130. See

ders, 416-18; napping frequency, 434;

also individual films





Circadian rhythms, 131-32; actigraphic measurements, 4; in adolescent sleep cycles, 15, 642-43, 660-61; and chro-

Cohen, D. B., 321, 322 Coleridge, Samuel Taylor, and dreaming, 142-43, 390, 509

notype, 121; in consciousness disorders,

College students and sleep, 805

670; and dream-lag effect, 228; and

Color in dreams, 144-45, 164-65, 370

gene modification, 303; and hibernators,

Color psychology studies, 144

635; in honeybees, 672; and hormonal

Colvin, Shawn, 431

secretions, 624-25; influence of mela¬

Comics and dreams, 146-47

tonin, 5; and mouse studies, 306-7; and

The Committee of Sleep: How Artists, Sci¬

napping, 434, 436; PSG measurements,

entists, and Athletes Use Dreams for

72; role in sleepiness, 10; and shift work

Creative Problem-Solving-and How

effects on, 621-22; and short sleep,

You Can Too (Barrett), 802

589; and university students, 695-96; and work schedule effect on, 241; and yawning, 809. See also Self-assessment

Comorbidity between epilepsy and sleep disorders, 147-49 Comparative sleep databases, 149-52;

tools of Circadian typology in children,

data obtained in laboratories vs. in the

adolescents, and adults

wild, 151-52; data quality, 150-51; of

Circadian rhythm sleep disorders (CRSD), 417-18, 696

dream colors, 145; of dream journaling, 373, 375; historical development, 50;

“The Circular Ruins” (short story), 279

phylogeny of sleep database, 504-6;

Cirelli, C., 307

sleep expression comparative statistical

Cl score sheet, 109-10

analysis, 152-53; sleep quotas, 149-50

City of Women (film), 128

Comparative sleep regulation, 153-54

Clairvoyance, 256-57

Complaints, increasing sleep, 347-49

Clark, J„ 322

Computed tomography (CT), 258

Classifications of dreams, 195-95

Conceptions of dreaming in the Western

Climatic factors of sleep, 45-46

Desert of Australia, 155-56

Clinical aspects of nightmares, 132-33

Confessions (Augustine), 423

Cockburn, Bruce, 431

Confusional arousals, 481

Cocteau, Jean, 131

Connection between dreams and mood,

Cognitive approach to dreaming, 133-35, 364


Cognitive-behavior therapy (CBT): imag¬

Consciousness disorders and sleep, 670-71

ery-rehearsal treatment, 133, 216, 401;

Consciousness in dreams, 159-60,

for nightmares and insomnia, 217, 401; for reducing cognitive hyperarousal,


655; for reducing depression, 706;

Consistent right-handedness (CRH), 320-22

using dreams in, 793-94

Contemporary theory of dreaming,

Cognitive expertise and dreams, 135-38 Cognitive theory of dream meaning, 139-41

161-62 Content analysis of dreams: basic princi¬ ples, 162-63


Continuity hypothesis and colors in dreams, 164-65 Continuity hypothesis of dreaming, 156-57,165-67, 199, 302 Convergent evolution of REM sleep in mammals and birds, 169-71 Cortical EEG oscillations, local sleep, and dream recall, 172-73 Corticotropin-releasing hormone CRH, 330-33 Cortisol, 249-51, 330-34, 337, 339,


Crick, Francis, 299, 561-62 Crime and Punishment (Dostoevsky),

390 Crispe, Thomas, 527 Critically ill patients and REM (rapid eye movement) sleep, 533-36 Cross-cultural approaches to dreams, 186-88 CST. See Costly signaling theory (CST) Cultural dimensions of sleep, 188-89 Cultural diversity and dreaming, 190-92

455, 469, 578.625-26, 631, 651, 669;

Culture and sleep, 604-5

and diabetes, 631; in endocrinology

Cushing’s disease, 333

of sleep, 249-51, 625-26; and growth

CVD. See Cardiovascular disease (CVD)

hormone releasing hormone, 337, 339;

Cytokines, 201, 594-95, 684, 699

and HPA system, 330-34; and PTSD, 651; and sleep loss/fragmentation, 469 Co-sleeping, 47-48, 174-78; cultural

Dali, Salvador, 130, 182, 197, 235, 328 Damasio, Antonio, 579-80

differences, 175, 177-78, 189, 605;

Dangarembga, Tsitsi, 391

mother-infant sleep proximity, 174; re¬

Daniel (Old Testament), 79

lationship with breastfeeding, 174-78;

Daniel (Old Testament), 79

and risk factors, 177-78; vs. solitary

Darwin, Erasmus, 143

sleeping infants, 175

Databases of comparative sleep, 149-52

Costly signaling theory (CST), 178-81;

Davis, F. C., 280

and emotions, 180; examples in ani¬

Davis, Lucy, 182

mals, 179-80; relationship to dreams,

Dayak people, 190

180-81 Counterfactuals in dreams (imaginative scenarios), 181-82 Coxhead, David, 801 CPAP (continuous positive airway pres¬

A Daydream (poem), 143

Daydreaming, 13, 143, 159, 161,746-47 Day-residue effect, 227-28 Daytime sleepiness. See Excessive day¬ time sleepiness (EDS)

sure) treatment: adherence challenges,

Dead of Night (film), 128

168-69; advances in technology, 169;

Deafness, effects on dream content of

and Alzheimer’s disease, 168; and heart

blindness and, 238-40

failure patients with OS A, 636; for

Death themes in dreams, 199

hypertension and cardiac conditions,

DeCicco, T., 341

167-68; for OSA, 148, 167-69,469

Declarative memory: and dream recall,

Creative problem solving in dreams, 182-85 Creativity: art therapy and dreams, 52-54; dreams as inspiration for, 235

173; neurofeedback effects on, 457; and spindles, 293; in transcranial direct current stimulation studies, 791. See also Sleep, memory, and dreams





De Continentia (On Continence) (Augus¬

tine), 423

Developmental psychology research, 13 Development and initial validation of

“Deep Image” poets, 509

Iowa Sleep Disturbances Inventory

Default mode network (DMN), 598-602

(ISDI), 204-5

De Gennaro, L., 26, 321

De Vere, Alison, 39-40

De Koninck, J., 607

Devereux, G., 190

Delaney, G., 350

The Devil in dreams, 353

Delaney, Gayle, 350, 393

Diabetes: and alexithymia, 29; and

Delayed sleep-phase syndrome (DSPS), 132, 693,696

chronic kidney disease, 529; and chronic renal failure, 358; and napping,

Delirium tremens, 212

434; and OSA, 468-70; and risks from

Delta (stage 4) sleep, 203

short sleep, 590; and sleep shortages,

Deluge, Yves, 275 Delusions and the classification of typical dreams, 194-95 De Manaceine, M., 208-9

45 Diabetes and obstructive sleep apnea, 468-69 Diagnostic and Statistical Manual of

Dement, W„ 209, 297-98, 656

Mental Disorders: assessment of de¬

Dement, W., 83, 100

pression, 202; classification system

Dement, William, 185

comparison, 524; illustration of grandi¬

Dementia with Lewy bodies, 101

ose delusions, 194; nightmare disorder

Demographic factors of sleep, 45-46

inclusion, 248, 463; nightmares inclu¬

Demon dreams, 403

sion, 401, 650; psychiatric disorders,

Demonic dream dictionary (Ancient

definition, 606; PTSD inclusion, 606;

Egypt), 34 Depictions of dreams, 195-98 Depression: and alexithymia, 26-28; as

seasonal affective disorder description, 570 Diagnostic and Statistical Manual of

cause of sleep shortages, 45; connec¬

Mental Disorders (DSM), 194, 202,

tion to dream imagery, 157; in dream


analysis, 162; and dreaming, 199-200;

Dickens, Charles, 128

in patients with kidney disease, 201-2;

Diet: in Bedouin tradition, 73-74; Kel¬

and reduced dream recall, 199-200.

logg’s dream recommendations, 375

See also Major depressive disorder

Disconnection from the external environ¬

Deprivation of sleep: for long periods, 45

ment during dreaming, 206-7

Depth of sleep, 202-4

Discovery of REM sleep, 208-9

Derbyshire, A. J., 209

The Discreet Charm of the Bourgeoisie

Deren, Maya, 125, 130, 197, 198 De Saint Denys, Hervey, 208 De Santo, R. M., 29

(film), 129 Disguise-censorship paradigm (Freud), 9, 445-46

A Descent into the Maelstrom (Poe), 278

Distinctive dream content associated with

Detailed focal vision, sleep and evolution

REM sleep behavior disorder (RBD),

of, 615-17




Disturbed sleep and posttraumatic stress disorder (PTSD), 215-17

Dream-film analogy (academic film the¬

Divination During Sleep (Aristotle), 613

Dream groups: leadership of, 387-89;

ory), 126

Divorce and children’s dreams, 116-17

safety factors, 565-66; in varying reli¬

Dizygotic (MZ) twins, 303

gions, 123-24

Djonlagic, Ina, 185 DMN (default mode network). See Brain networks and sleep

Dream imagery, 134, 218; ancient Greek, 32; cancer patient dream work, 105-8; healing using, 108; and mood, 157-58;

Doll, E„ 163

pain-dream connection in endometrio¬

Domhoff, Bill, 393-94

sis patients, 255-56; usage in dream art

Don Quixote (Cervantes), 390

therapy, 54

Doucet, Julie, 147 Dr. Jekyll and Mr. Hyde (Stevenson),


The Dream in Clinical Practice (ed. Nat-

terson), 524 Dream incubation: Islamic dream incuba¬

Draper, P., 266

tion, 370-71; school of metaphysics

“Dream, Caused by the Flight of a Bum¬

approaches to, 566-69

blebee around a Pomegranate a Second

Dreaming, functional theories of, 297-99;

Before Awakening” (painting) (Dali),

an alternative theory, 299; critique of


evidence in favor of dream function,

A Dream (poem), 196

298; evidence against the dream-func¬

“The Dream Approaches” (painting)

tion hypothesis, 298-99; philosophical

(Dali), 182 Dream art therapy, 54 “Dreamatarian Diet,” 375 DreamBank.net: an online archive for studying dream content, 141, 223-25, 727 Dream cachet (protection amulet), 75 Dream censorship, neuroanatomical cor¬ relates of, 445-47 Dream characters, 110-13; gender differ¬

issues, 297-98 Dreaming: The Journal of the Association

for the Study of Dreams, 226, 360 Dreaming and sleep disorders, 645-46 Dream interpretation, and meaning of dreams, 407-8 Dream interview: a client-defined, meta¬ phor-based interpretation, 217-19 Dream Interview Method (Delaney), 393 Dream journaling, 105,373-77

ences, 301; gender distribution of, 115,

Dream journals, 141, 223-24, 257

491; and handedness, 322; and phi¬

Dream-lag effect, 227-28

losophy of mind, 490-93; use in child

Dream narratives, structural analysis of,

therapy, 118


Dream consciousness, 159-60

Dream News (e-newsletter of IASD), 360

Dream-content analysis, 8-9, 223-25,

“Dream of a Girl Chased by a Nightin¬

301 Dream content analysis: basic principles, 162-63 “The Dream” (painting) (Dali), 182

gale” (painting) (Ernst), 182 Dream of Scipio (Cicero), 508 Dream of the Rarebit Fiend (comic strip),

127, 146





Dream of the Red Chamber (China), 390 Dream phenomenology, 135 Dream recall, 537-38; age and frequency

Dream sharing as social interaction,

219-22 DreamShift process, 362-63

of, 21-22; in alexithymia, 26; in Bed¬

Dreamside (Joyce), 279

ouin culture, 74; and brain damaged

Dreams of the Rarebit Fiend serial news¬

patients, 94-95; in children, 62, 115;

paper comic, 146

and cognitive approach to dreaming,

“Dreams of Venus” (painting) (Dali), 197

134-35, 137; cortical EEG oscillations,

Dreams That Money Can Buy (film), 197

local sleep, and, 172-73; declines in

Dream Telepathy (Ullman, Krippner, &

elderly, 638; and depression, 199-200; effects of medication, 237; frequency discrepancies, 298, 421, 512, 521;

Vaughan), 257 Dream theory (Jung), 314, 324, 341, 361, 377-78,380-81

gender differences, 301; and handed¬

Dream Threat Scale, 18

ness, 320-22, 320-22; and local sleep,

Dream Time (magazine of IASD), 360

172-73; memory challenges, 94; neu¬

DreamTime periodical, 803

rophysiology of lost dream recall,

Dreamtoons graphic novel (Reklaw), 311,

457-59; predictors of, 419; and sleep


disorders, 645-46; value of, 299; and

Dreamt songs, 2

waking life effects, 235

“A Dream within a Dream” (poem), 278

Dream reporting, 133, 135, 162-63, 186-88, 219, 223-24; and cognitive

Dreamwork in counseling, 229-30, 308-10, 325-27

approach to dreaming, 133, 135; and

Dreamworks periodical, 803

content analysis of dreams, 162-63;

Driving and sleepiness, 721-23

cross cultural approaches, 186-88;

Drosophila (fruit fly) studies, 154, 306,

DreamBank.net, 223-24 Dream Research Program, 239 “The Dream” (painting) (Rousseau), 197

672-74 DSM. See Diagnostic and Statistical Manual of Mental Disorders (DSM)

Dreams (film), 197

Duchamp, Marcel, 197

Dreams, logical structure of, and their re¬

Duration of sleep and mortality, 460-61

lation to reality, 394-96

Durer, Albrecht, 182

Dreams, memory, and sleep, 687-91

Duval, M„ 209

Dreams: Visions of the Night (Coxhead

Dynamic structure of reptilian EEG ver¬

and Hiller), 801 Dreams 1900-2000: Science, Art, and the Unconscious Mind (Gamwell), 197

sus mammalian sleep EEG, 231 Dysfunctional Beliefs and Attitudes about Sleep questionnaire, 712

Dreams as inspiration for artists, 182-85 DreamSat (software), 141, 318

Eberwein, Robert, 126

Dreamscape (film), 129

Ecology of sleep, 45-46

Dream self, 110-13

Ecstasy (MDMA) use and sleep prob¬

Dream series collections (of Domhoff, Hall, Van de Castle), 393-94

lems, 233-34 The Edge of Dreaming (film), 325

Index Edison, Thomas, 362

Embodied imagination (El), 244-46

EEG (electroencephalography) measures:

Emecheta, Buchi, 391

and adolescent brain development,


EMF. See Electromagnetic fields of mo¬

15-16, 657-58; and alcohol use, 23;

bile telephones and sleep parameters

basics of sleep recordings, 69-71; in

EMG (electromyography) measures: ab¬

bird sleep studies, 170-71; and bizarre

normalities/increases with RBD, 214,

imagery and though, 82-83; cortical

216; cardiorespiratory polysomnogra¬

oscillations, local sleep, and dream re¬

phy, 71-72; common artifacts, 72

call, 172-73; delta activity measure¬

Emotionally intense dreams, 25-26

ments, 96; and depth of sleep, 203;

Emotions Questionnaire Selections, 735

and disconnection from external en¬

Endocrine system and sleep, 624-27

vironment during dreaming, 206-7;

Endocrinology of sleep, 249-54; galanin,

dynamic structure of reptilian versus

251; gonadal hormones, 252; hypocre-

mammalian sleep EEG, 231; and Ec¬

tins/orexins, 251-52; hypothalamo-

stasy users, 233; features of NREM

pituitary-thyroid system, 250-51;

sleep, 100, 153-54; and HPA system,

neuroactive steroids, 252, 254; Prolac¬

331-34; low-voltage activity, 193, 206,

tin, vasoactive intestinale polypeptide,

208-9; in mammalian sleep cycle stud¬


ies, 150-51; and mouse studies, 307;

Endometriosis and dreams, 255-56

and neuroimaging research, 293, 598;

End-stage renal disease (ESRD), 201-2,

polysomnography (sleep EEG), 249;


in REM research on cats, 209; reptil¬

Energy level assessment, 95-97

ian versus mammalian sleep EEG, 231;

Engelhardt, H., 62

role in discovery of REM sleep, 208-9;

English Romanticism, 142

seep and brain networks, 597-602;

EOG (electrooculogram) measures,

slow-wave activity in NREM sleep,


153-54; spindles, 253-54, 456-57,

The Epic of Gilgamesh, 278

657, 689, 713-14. See also Neuroana-

Epilepsy: CPAP treatment for, 148; noc¬

tomical correlates of dream censorship;

turnal frontal lobe type, 147-48; and

Neuroanatomical correlates of dream-

obstructive sleep apnea (OSA) corre¬

work; Neuroanatomy of dreams; Neu¬

lation, 147-48; seizures, 147-48; and

rofeedback for sleep problems

sleep disorders, 147-49

“The Effect of Dream Deprivation” (ar¬ ticle), 297-98 Egypt. See Ancient Egypt dream beliefs 8V2

(film), 128, 196

Episodic memory, 95 Erections (penile): and flying dreams, 284; and REM sleep, 151, 208-9, 284 Ermacora, G., 479

Elderly persons: REM sleep, vs. adoles¬

Ernst, Max, 182, 197

cents, 21 Electromagnetic fields of mobile tele¬

Ernst: Pieta or Revolution by Night

phones and sleep parameters, 243-44 Elias, M. F., 176

(Gee), 801 ESP (extrasensory perception) in dreams,

256-58, 277





ESRD. See End-stage renal disease

Female genitals in dreams (China), 120

Eternal Sunshine of the Spotless Mind

Fetal sleep, 279-81

(film), 129 Evolutionary approaches to sleep,

Fetal yawning, 281-83 Fine, G„ 219-20

262-67; attachment theory, 266-67;

Finland sleep surveys, 348

behavioral ecology and life history,

Fireworks (film), 130

262- 63; parent-offspring conflict,

Fisher, C., 656

265-66; pregnancy and genetic con¬

Fisher, Farry, 191

flict, 264-65; sex-ratio determination,

Five Fectures on Psycho-Analysis

263- 64; sleep as a scarce resource, 263 Evolutionary psychology theories of

(Freud), 292-93 The 5000 Fingers of Dr. T. (film), 128

dreams: costly signaling theory, 268;

Flanagan, Owen, 299

dreaming as psychotherapy, 268; sen¬

Fleming, Victor, 197

tinel theory, 267; simulation theories,

“Flight through the Tunnel” (painting)

268; threat-simulation theory, 268-69 Excessive daytime sleepiness (EDS), 101, 667-69, 679

(Bosch), 196 Flying dreams, 283-85 Flying in dreams: the power of the image,

Existential dreams, 269-71, 345

285-88; air-robics: the phenomenon of

Experimental dream psychology, 133

dream flying, 285-86; intention flying

Extended overgeneral memories, 473

and guided imaging, 287, 289; styles of

External sensory stimulation as a tech¬

dream flying, 287

nique to study dreaming, 271-74; PGO

fMRI (functional magnetic resonance

wave and dream theories, 271-72;

imaging): alexithymia and dreams,

PGO waves, eye movements, and ex¬

97; and comic book readers, 311; and

ternal stimuli, 273-74; problems of

neuroimaging research, 293, 598; and

testing a PGO model, 272

sleep spindles, 714; studies of REM

Eyes Wide Shut (film), 129

sleep, 162; vision in dreams studies, 97-99. See also Functional neuroimag¬

Fabiao, Solange, 182

ing during human sleep

Fairbairn, W.R.D., 579-80

Foer, Safran, 392

Faith, L., 186

Forbes, A., 209

False-awakening dreams, 403

Forced sleep, short-term, 461

False awakenings, 275-76

The Forgotten Ones (film), 197

Family unconscious in dreams, 276-78

Fomari, Franco, 288-89

Fantasy literature and dreams, 278-79 Faraday, Ann, 393

Foulkes, D., 114-15, 134, 139, 141, 289, 343, 480

Fatal familial insomnia (FFI), 212, 303

Fox, George, 527-28

Fechner, Gustav, 574

Fragmentation of sleep, 658-59; and al¬

Federn, Paul, 284

cohol intake, 23; in Alzheimer’s, 675;

Feeling and Form (Langer), 125

and arthritis, 593-94; in conscious¬

Fellini, Federico, 128, 183, 196

ness disorders, 670; in critically ill



patients, 533-36, 697-98, 700; and

studies, 385; and lesion studies in

mild cognitive impairment, 618; in

humans animals, 789, 792; of lucid

narcolepsy, 329, 441; and nightmares,

dreaming, 90-91; measures of shar¬

464; and obesity, 468; in obstructive

ing in waking and dreaming, 97-99;

sleep apnea, 148, 303, 468-70; in older

and neurological damage, 450; of OSA

women, 638; in Parkinson’s disease,

patients, 148; and personality studies,

678-79; and suicide, 624

653; and PGO testing limitations, 272;

Fragrance and dreams. See Olfactory stimuli and dreams Frank, M. G„ 280

and prefrontal cortex studies, 515-16; sleep compared to waking studies, 513 Fuseli, Henry, 196

Frankenstein (Shelley), 183

Freeman, Arthur, 793

Gackenbach, Jayne, 226, 799

Freud, Sigmund: approach to dreams,

Gaiman, Neil, 147, 279, 311

218, 276, 291-93, 437, 447-48, 454,

Galanin, 251

574; condensation concept, 448-49;

Galen, 341, 361

disguise-censorship paradigm, 9,

Gamers. See Video game play and

445-46; distinctions of dream the¬


ory, 388; flying in dreams, 284; influ¬

Gamwell, Lynn, 197, 801

ence on art, 801; opinion of Jung, 377;

The Garden of Boccaccio (poem), 143

pre-Freud unconscious and dreams,

Garfield, Patricia, 324

787-88; sexuality in dreams, 89; tages-

Gee, Norman, 801

reste (day residue) usage, 165; talking

Geldmacher, L. L., 810

cure use of dreams, 523. See also The

Gender differences in dreams, 301-2

Interpretation of Dreams

Gendlin, Eugene, 85

From Angels to Neurones: Art and the New Science of Dreaming (Hobson and

Wohl), 801 Functional magnetic resonance imag¬

Generalized anxiety disorder (GAD), 463, 606 Genesis (Old Testament), 78-80 Gene therapy, 328-29

ing (fMRI): alexithymia and dreams,

Genetics and epigenetics of sleep, 302-4

97; and comic book readers, 311; and

Gene transfer, hypocretin in mice models

neuroimaging research, 293; studies of

of narcolepsy, 328-29 Genital symbolism in dreams (China),

REM sleep, 162; vision in dreams stud¬ ies, 97-99 Functional neuroimaging during human

119-20 Genomic imprinting, 304

sleep, 293-95; alexithymia measure¬

Gerard, R. W„ 154

ment, 25, 97; and brain-activation lev¬

Gestalt dreamwork, 308-10, 326

els of REM sleep, 181, 453, 454-55;

GH (growth hormone), 249, 250, 330,

and discovery of REM sleep, 208; dreams, personality and, 653; and external extrasensory stimulation, 273-74; and Kleine-Levin syndrome

332, 334, 625-26 Ghost tales. See Sleep-related hallucina¬ tions and ghost tales Ghouls, in Bedouin tradition, 76





Ghrelin, 336, 339-40, 590, 603, 625-26, 631, See also leptin GHRH (growth hormone releasing hor¬ mone), 336-38 Gibson, Ralph, 494 Gilgamesh (poem), 389, 508

Hagiography (medieval) and dreams,

415-16 Haig, D., 264-65 Hallam, F. M., 208 Hall and Van De Castle scoring system, 807

Gilliam, Terry, 39

Hallowed, A. I., 190

Ginsberg, Allen, 509

Hallschmid, M., 791

Girls: animal figures in dreams, 37;

Hallucinations: hypnagogic hallucina¬

dream content compared with boys, 14,

tions, 100, 211, 303, 351, 354, 368,

115 Globalization and culture change, 48

438-40; hypnopompic hallucinations, 132, 327, 438-40; sexual, 64, 366,

Globus, G., 480

368; in sleep paralysis, 64, 366; sleep-

Gluck, Louise, 510

related, and ghost tales, 708-11

Glucocorticoid, synthetic, 333

Hall-Van de Castle coding system for the

Godbout, R., 607

study of dream content, 140-41, 186,

The Golden Ass (Apuleius), 278

187, 214, 223, 317-19, 373-74, 491,

Gomez, E., 238


Gonadal hormones, 252

Hamid, Alexander, 197, 198

Gondry, Michael, 131

Handedness: effects of dream recall and

Grade point average (GPA) and sleep is¬ sues, 694

content, 320-22; sleep variables and,


Graff, Dale, 257

Hardie, Amy, 325

Grandner, M. A., 348

Harmala plant (Bedouin psychoactive

Granger causality, 207

plant), 74

Graphic novels and dreams, 310-14

Harry Potter (Rowling), 279

“The Great Red Dragon and the Woman

Hartley, David, 143, 299

Clothed with the Sun” (painting) (Blake), 196

Hartmann, Earnest, 106, 109, 161-62, 226, 322

Gregor, T., 186

Harvard University, 185

Gross, Anthony, 40

Harvey, E. N., 209

Group work with dreams, 314-16; and

Hauri, P., 200

Buddhism, 315; and Islam, 315; and

Hayano, J., 29

Judaism, 315; and Presbyterians, 315.

Head, Bessie, 391

See also Ullman method of group

Healing and dreams, 323-25


Healing Dreams (Barasch), 324

Growth hormone release, 617 Gujar, N., 25

The Healing Power of Dreams (Garfield),

324 Healing Power of Dreams project, 105

I Had the Craziest Dream Last Night

(Rabinowe), 53

Healing Sounds from the Malaysian Rain¬ forest (Roseman), 430


Heart failure patients and sleep disorders,


Hufford, David, 351, 367 Hiillstrung, H., 209

Hecht, Ben, 130

Humanistic Movement, 308, 395

Hellenistic Greek cultures, 61

Hurovitz, C. S., 238, 239

Heller, H. C„ 96, 280

Huxster, J. K., 233, 234

Hemodialysis (HD), 29, 201, 529, 647-48

HVS (high-voltage spike), 260-61

Hemo-dialysis (HD), 201-2

Hypermotor seizures, 482

Herbed pillows of Bedouins, as sleep aid,

Hypersomnia: effects of medication


on, 236-37; idiopathic hypersomnia,

Herodotus, 51

520-21, 645-46; Kleine-Levin syn¬

Hibernation: and seasonal affective dis¬

drome, 385-86; and psychiatric dis¬

order, 571; and thermoregulation,

orders, 692; and seasonal affective


disorder symptoms, 570; and suicide,

Hill dream model, 325-27 Hiller, Susan, 801

623; vs. narcolepsy, 645-46 Hypersomnolence. See Idiopathic hyper¬

Hinduism, 541

somnia; Primary disorders of hyper¬

Hippocrates, 22, 323-25, 341, 350, 361,

somnolence and dreams; Recurrent

422 Historical background of sleep medicine,

101-2 History (Herodotus), 51


hypersomnias Hypnagogic hallucination-like ghost tales (HyH), 708 Hypnagogic hallucinations, 438-40,450;

Hitchcock, Alfred, 130, 197

and Agrypnia Excitata, 211; and hyper¬

Hobart, G. A., 209

somnolence, 520; and isolated sleep pa¬

Hobson, J. Allan, 7, 187, 269, 272, 284,

ralysis, 351, 354, 368; and narcolepsy,

656, 801 Hoffman, V. J., 365-66 Holocaust and Rwandan genocide survi¬ vors, dream accounts, 749-51 Homeostatic regulation of sleep, and sleep intensity, 121-22, 686-87 Homer, 35, 49, 278 Hoppin, Hector, 40 Horowitz, Paul, 184 Hoss, Robert, 144, 257, 309-10 HPA (hypothalamo-pituitary-adreno-

303, 441, 521; and REM sleep, 100, 553 Hypnagogic hypnosis-like ghost tales (HHy), 708, 710 Hypnagogic imagery, 100, 132, 136, 245, 303, 327-28 Hypnopompic hallucinations, 132, 327,

438-40 Hypocretin deficiency, and narcolepsy symptoms, 440-42 Hypocretin/orexins, and narcolepsy, 100,


cortical) system and sleep, 249, 250,

330-34 HPS (hypothalamo-pituitary-somatotrophic) system and sleep, 249, 330, 334,

336-40 Huang, Alan, 184

IASD Ethical Guidelines (IASD), 387

ICSD (International Classification of Sleep Disorders), 63 Idiopathic hypersomnia (IH), 520-21, 643, 645-46





idiopathic REM Behavior Disorder (iRBD), 554-56

(RLS), 358; and suicide, 622-23; and video/computer game playing, 411. See

Iliad (Homer), 35, 49, 57, 278

also Sleep, psychiatric disorders, and

Illness and dreams, 341-42

the transdiagnostic perspective; Sleep

Illusory contents in dreams, 342-44

disorders and dreaming; Sleep-related

Imagery rehearsal therapy (IRT), 133,

mental activities in insomnia: role and

401-2, 606 Imaginary rescripting method, for chil¬ dren, 118 Imaginative scenarios (counterfactuals), 181-82 Impactful dreams, 344-45 “In a Dream” (drawing) (Kubin), 197 Inception (film), 129

Inconsistent handedness (IH), 320-22

assessment Insulin: and CPAP therapy, 168; and level variance in sleep, 626; obesity and insulin resistance, 630; and OSA, 468-69, 468-70; and short sleep, 590, 631; and sleep loss, 603 Interictal EEG epileptiform abnormalities (IEAs), 148 International Association for the Study of

Incubation of dreams, 349-50

Dreams (IASD), 359-60; cancer pa¬

Incubus/succubus, 351-54

tient dreamwork program, 105; Dream¬

In Dreams (film), 129

ing journal creation, 226; and dream

Infancy and early childhood, sleep devel¬

journaling, 374; dreamwork ethics

opment, 639-41 Infant sleep and parenting, 354-55 Infant sleep interventions, 356-57

statement, 387, 565; educational offer¬ ings, 765; origins of, 314 International Association for the Study

Inland Empire (film), 129

of Dreams (IASD), 105-9, 226, 314,

Insects and sleep, 671-74


De Insominiis (On Dreams) (Synesius of

Cyrene), 390

International Classification of Sleep Dis¬ orders: and adult nightmare content,

Insomnia: actigraphic evaluation, 4-5;

385; Kleine-Levin syndrome diagnostic

alexithymia and, 26-27; Brazilian

criteria, 385; paradoxical insomnia cri¬

study, 348; and causal medications,

teria, 655; REM sleep behavior disor¬

638; in chronic renal failure, 357-58;

der criteria, 550; on sleep paralysis, 63;

drug therapy for, 358; fatal familial in¬

sleep talking criteria, 715

somnia, 212, 303; female prevalence of, 348; genetic influences, 303; hy¬ pothyroidism association, 250; im¬

International Diabetes Foundation (IDF), 630, 632 International Statistical Classification of

mune function and, 30; influence of

Diseases and Related Health Problems

alcohol, 23-24; Iowa Sleep Distur¬

(WHO), 524

bances Inventory study, 204-5; life

Interpersonal Reactivity Index, 653

course symptoms, 47-48; medication

The Interpretation of Dreams (Freud), 17,

influence, 236-37, 414; physiological

229, 235, 291-92, 298, 377, 454, 509,

changes, 339; and psychiatric disor¬


ders, 692; and restless legs syndrome

Intersubjective dreams, 361

Index Intuition in dreams. See ESP (extrasen¬ sory perception) in dreams “Invasion of the Night” (painting) (Matta), 197

Joel, Billy, 183-84, 431 Johns, Jasper, 183 La Joie de Vivrer (Hoppin and Gross), 40

Jones, Ernest, 351, 367

Involuntary nature of dreams, 363-64

Jones, K. A., 233, 234

Iowa Gambling Task, 92

Joseph (Old Testament), 79

Iowa Sleep Disturbances Inventory

Journaling of dreams, 105, 373-77

(ISDI), development and initial valida¬

Jouvet, Michel, 228

tion of, 204-5

Joyce, Graham, 279

iRBD (idiopathic REM Behavior Disor¬ der), 554-56


Judaism: dream groups, 123-24; and the Hebrew Bible, 541; Israeli’s writings

Iroquois dream practices, 192

on dream imagery, 423; Kabbalistic

Islam and dreams, 364-66; Bedouin

dream interpretation, 423-24

dream traditions, 73-76; bizarre and

Juliet of the Spirits (film), 128

jumbled dreams subtype, 365; dream

Jung, Carl: archetypal dream symbols de¬

groups, 123-24; Ru’ya subtype,

velopment, 116, 378; distinctions of

364-65; self-talk subtype, 365; Tabir

dream theory, 388; dream journaling

dream interpretation science, 365

of, 373; dream theory, 314, 324, 341,

Islamic dream incubation (Istikhara),

361, 377-78, 380-81; on four orient¬

370-71 Isolated sleep paralysis (ISP), 366-69;

ing functions of consciousness, 145; in the function of dreams, 80; “On the Na¬

and Hmong refugees, 369; and hypo-

ture of Dreams” (essay), 81; opinion of

cretin deficiency, abnormal REM sleep,

Freud, 377; on sexuality, 89; subjective

440-42; and narcolepsy, 438-40;

dream distinction, 467; synchronicity

physical correlates, 367-68; psycho¬

definition, 375; transcendent function:

logical and co-creation, 366; role in

neurological support, 380-82; under¬

history and myth, 368-69

standing of dream images, 394. See

Isola Tiberi healing shrine, 57

also The Red Book

Israeli, Isaac, 423

Jtirgenssen, Birgit, 196

Italian Psychoanalytic Society, 288

Juvenile idiopathic arthritis (JIA), 593-94

Jackson, John Hughlings, 208

Kabbalistic dream interpretation, 423-24

James, William, 574-75

Kafka, Franz, 390

Japan: dream beliefs, 55; increased life

Kahlo, Frida, 182, 197, 235

expectancy, 460; polyphasic sleep cul¬

Kalapalo people, 190

ture in, 189; recognition of hypersom¬

Kant, Immanuel, 208

nia, 520

Kapukurri (dream), in Kukatja language, 1

Japanese dream reports, 187

Kaufman, Charlie, 131

Jeremiah (Old Testament), 79

Keaton, Buster, 128

Jeunet, Jean-Pierre, 39

Kerouac, Jack, 183, 509

Joel (Old Testament), 79

Kerr, N. H„ 238





The Key of Dreams (Artemidoris of Ephe¬

sus), 611

Langer, Susanne, 125, 126 The Lathe of Heaven (LeGuin), 279

Kidney disease. See Renal disease

Leading dream groups, 387-89

King, Stephen, 183, 390

Leger, Fernand, 197

King Lear (Shakespeare), 584

LeGuin, Ursula K., 279

Klein, Melanie, 288, 314

Leighton, L., 219-20

Kleine-Levin Syndrome, 385-86

Leptin, 468, 590, 603, 619, 626, 631, See

Kleitman, Nathaniel, 7, 22, 100, 208, 209, 297-98, 656

also ghrelin Let Me Dream Again (film), 127

Koffel, Erin, 205

Levertov, Denise, 510

Kohlschutter, Ernst Otto Heinrich, 202-3

Lewin, Bertram, 126

Kohut, Heinz, 579-80

Lewis, Jacquie, 38

Kojima, M., 29

Liddon, Sim, 351

Kooiman, C. G., 26

Life cycle, and women’s dreams, 806-8

Korean culture: dream beliefs, 55; tradi¬

Light phase response curve (PRC), 121

tional dreams, 774-75

Lilith (Babylonian demonness), 352, 368

Krakow, Arthur, 793

Linklater, Richard, 40, 131

Kramer, Milton, 200, 523

Literature and dreams, 389-92

Krims, Les, 495

Little dreams, 392-94. See also Big

Krippner, Stanley, 186, 187, 480 Kroeber, Alfred, 192 Kronholm, E., 348

dreams Little Nemo in Slumberland (comic strip),


Kubin, Alfred, 197

Living in Oblivion (film), 129

“Kubla Khan” poem (Coleridge), 143,

Locke, John, 143


Loewi, Otto, 184, 298

Kubrick, Stanley, 129

Loewy, R., 209

Kuiken, Don, 226, 235

Logical structure of dreams, and their re¬

Kumin, Maxine, 510

lation to reality, 394-96

Kunzendorf, Robert, 197-98

Long sleep duration, 460-61

Kupka, Frantisek, 196-97

Long-term (dream) journal keeping

Kurnai people (of Gippsland), 1

(LTJK), 374-76

Kurosawa, Akira, 131, 183, 197

Loomis, A. L., 100, 209

LaBerge, Stephen, 325, 656

Lost dream recall, neuropsychology of, 457-59

Labrador, sleep paralysis beliefs, 64

Lovecraft, H. P., 278-79

Lacan, Jacques, 126

Lucid dreaming therapy for nightmares,

Ladysmith Black Mambazo, 431 Laertius, Diogenes, 60 “Landscape from a Dream” (painting) (Nash), 182 Langer, Susanne, 314

401-2 Lucid dreams and dreaming, 397-98; and Agrypnia Excitata, 211; brain corre¬

lates to lucidity, 90-92, 398; definition, 397-98; experiences of shamans, 129,


191; false awakenings and, 275-76;

Massine, Leonide, 197

genital arousal association, 353; global

Mathematical modeling of sleep, wake

definitions of, 187; and handedness,

rhythms, 122

321; and healing processes, 325; and

Matta, Roberto, 197

impactful dreams, 344; and isolated

Maury, Alfred, 208, 327-28, 655

sleep paralysis, 369; in literature, 279;

McCarley, Robert, 7, 272, 284

mechanics of, 275, 325; in reports of

McCartney, Paul, 184, 235, 431

Bedouins, 74; and sleep paralysis, 369;

McCay, Winsor, 127, 146-47

in sports, 400-401; and states of being,

McGinn, Colin, 126

211; and time sense, 656; video gaming

McNamara, Patrick, 111, 129-30, 268,

association, 796-98 Lucid nightmares, 403-6 Lucretius, 169, 208 Lumiere, Auguste and Louis, 124, 128 Luminet, O., 25


322, 724-25 MDD (major depressive disorder), 451-52, 474, 606-7 MDMA (Ecstasy) use and sleep prob¬ lems, 233-34

Lumley, M. L., 26

Meatyard, Ralph Eugene, 495

Lundh, L.-G., 26-27

Media use: and nightmares, 409-10; and

Luther, Martin, 78-80. See also The

sleep in children, adolescents, 410-13;

Bible and dreams

television consumption and dreaming,

Lynch, David, 39, 129

767-68; video game play and dreams, 795-800

Lyons, Tallulah, 105, 325

Medications, effects of on sleep and Mack, John E., 129

dreaming, 235-38, 413-14, 413-14

Mack, Phyllis, 527

Medicine dreams of Native Americans,

Mackiewicz, M., 307 Mahowald, Mark, 7, 211 Maimonides Hospital (Brooklyn) ESP study, 257 Major depressive disorder (MDD),

442-43 Medieval hagiography and dreams,

415- 16 Mehinaku tribe (Amazonian), 186, 190 Meier, Carl Alfred, 59

451-52, 474, 606-7. See also

Melatonin, 131


Melatonin therapy: efficacy studies,

Malay people, 190

5; mechanism of release in body,

Male genitals in dreams (China), 119-20

412; role in circadian rhythms, 131;

Maleus Maleficarum (witch-hunting man¬

for sleep disorders of children, 347,

ual), 353 Malinowski, Bronislaw, 190

416- 18

Mardu people (of Australia), 1 Martin, Susanna, 353

Melies, Georges, 127-28, 196 Melville, Herman, 63 Memory. See Autobiographical memory;

Maslow, Abmham, 314

Declarative memory; Dreams, memory,

Massey, Irving, 431

and sleep; Nondeclarative memory

Massimini, M., 792

Mendeleev, Dmitri, 184, 362





Merchant of Venice (Shakespeare), 584 Meshes of the Afternoon (film), 130, 197,

198 Metabolic syndrome: and obstruc¬ tive sleep apnea, 468-69; and sleep,


Morningness-Eveningness Questionnaire for Children and Adolescents (MEQCA), 573 Morvan’s chorea, 212-13 Motor vehicle sleep related accidents, 721-23

Metamorphoses (Ovid), 278

Moulton, S. T., 246

Metaphysics. See School of Metaphysics

Mouse sleep physiology, genetics of,

approaches to dream incubation Metaplasticity, plasticity, and sleep,

701-3 Methodological challenges in scientific studies of dreams, 418-21 Metz, Christian, 126

305-7 Mugwort herb, dream-stimulating proper¬ ties, 425-29, 428 Mulholland Drive (film), 129

Multiple sleep latency test (MSLT), 10, 520-21,682-83

Meyers, Stephanie, 279

Multiple system atrophy, 101

Michals, Duane, 495

Mulvihill-Smith syndrome, 125, 212-13

Microsleeps (defined), 10

Miinsterberg, Hugo, 125

Middendorf, Helmut, 197

The Murders in the Rue Morgue (Poe), 278

Middle Ages and dreams, 421-24; conse¬

“The Musical Dream Revisited”

quences experienced by women, 369;

(Massey), 431

religious dream depiction, 196; use of

Music and dreams, 430-32

mugwort in amulets, 428

Muslim dream practices, 365

Middle Kingdom (Ancient Egypt), 33 Midsummer Night’s Dream (Shake¬

Muzio, J. N., 656 “My Dream” (painting) (Pankejeff), 197

speare), 584 Mikolajczak, M., 25

Naparstek, Belleruth, 107

Mild cognitive impairment and sleep,

Naps, 433-36; and acute sleep depri¬


vation, 10; Agrypnia Excitata and,

Mitchson, Graeme, 561-62

212; China and Japan’s polyphasic

Mobile phones. See Cell phone use

sleep cultures, 189; cultural varia¬

Moby Dick (Melville), 63

tions, 433-34, 604-5; defined, 433;

Molinari, Sergio, 289

frequency of African Americans,

Molle, M„ 791

433; health benefits of, 434; memory,

Monophasic sleep cultures, 189

dreams, and, 436; REM sleep studies,

Montangero, Jacques, 793

25, 160; sleep patterns of children, 46,

Mood and connection between dreams,

639-40; vigilance, performance, and,

156-58 Morgan, Robert, 40

435-36 Narcolepsy, 351; and abnormal REM

Morningness, age-related, 122

sleep, hypocretin deficiency, 440-42;

Morningness-Eveningness Questionnaire

and African Americans, 100; defined,

(MEQ), 573

438-39; and dissociated states, 211;



and dreaming, 437-38, 521; gene

Neural metaphor and dreams, 444-45

therapy treatment for, 328-29, 440;

Neuroactive steroids, 252-54

and genetics in sleep, 303; hypocre-

Neuroanatomical correlates of dream cen¬

tin gene transfer in mice models of,

sorship, 445-47

328-29; and isolated sleep paralysis, 366, 438-40; and REM sleep, 437-38;

Neuroanatomical correlates of dream-

and sleep medicine, 100; subcategories

Neuroanatomy of dreams, 449-51

of, 520. See also Hypnagogic halluci¬

Neuroanatomy of REM sleep and depres¬

nations; Hypnopompic hallucinations; Primary disorders of hypersomno¬ lence and dreams; Sleep disorders and dreaming Nash, Paul, 182 National Cholesterol Education Program (NCEP), 630 National Health Interview Survey, 593 National Institute of Mental Health (NIMH), 504 National Sleep Foundation (U.S.): report

work, 447-49

sion, 451-53 Neurobiology of psychoanalysis in wake and REM sleep, 454-55 Neurofeedback for sleep problems,

456- 57 Neuroimaging, functional during human sleep Neuropsychology of lost dream recall,

457- 59 Newfoundland, sleep paralysis beliefs, 64 New Kingdom (Ancient Egypt), 33-34

on use of electronic media devices,

Nielsen, Tore, 7-8, 227-28, 322

410-11; sleep recommendations for

Nigerian tribal study, 187

adolescents, 16; 2005 poll on adults’

Nightly sleep duration and mortality,

sleep habits, 433; 2006 Sleep in Ameri¬


can Poll, 410-11; 2007 sleep quality

The Nightmare (film), 127

study, 348

Nightmare disorder, 248, 463, 464, 693

Native Americans: ceremonial use of

“The Nightmare” (painting) (Fuseli), 196

mugwort, 428; dream beliefs, 567;

A Nightmare on Elm Street (film), 129

dream catchers, 74-75; dreams of,

Nightmares, 463-65; Brazilian sleep

442-43; importance of dreams for,

studies, 348; and Brazilian sleep

585-86; influence on African Ameri¬

studies, 348; children’s dreams and,

can dreams, 19; plants used in sweat

dreams, 801. See also Shamanism and

114-19; children’s dreams and night¬ mares, 114-19; clinical aspects of, 132-33; clinical definition, 401; con¬ tent in adults, 461-62; effects of sleep


medications on, 236; effects on day¬

lodges, 74; shamanic traditions, 801; vision quests of, 349; visual art and

Natterson, Joseph, 524

time mood, 235; emotional responses

Naturalistic philosophy (Aristotle), 422

to, 247-48; and endometriosis patients,

Negative REM dream, 476

256; and existential dreams, 269-71; as

Neider, Michelle, 92

film plots, 129-30, 197; of flying, 286;

Neural basis and theoretical models,

gender differences effect on, 301; im¬


agery-rehearsal therapy treatment, 133;





and impactful dreams, 345; and insom¬

69; changes during adolescence, 657;

nia, 645; as inspiration for painters,

and characters in dreams, 111; as com¬

196-98; as inspiration for poetry, 142,

ponent of sleep definition, 193; and

196; and the ISDI, 205; lucid dreaming

CRH, 148, 331; in different mammals,

therapy for, 401-2, 405; lucid night¬

149-50; and disconnection from ex¬

mares, 403-6; media use and, 409-10;

ternal environment during dreaming,

posttraumatic, 117-18; in PTSD,

206-7; and dream characters, 111; and

106, 118, 215-17, 270, 401, 463-64,

dream consciousness, 160; dream oc¬

510-11, 606; and REM sleep, 117-18;

currence during, 7-8; EEG features

research studies, 133; sleep, psychiatry,

of, 100, 153-54; and endocrinology of

and, 692-93; sleep paralysis, confusion

sleep, 249-54; and epileptic seizures,

with, 367; treatment modalities, 401; of

148; and fetal sleep, 280; five levels

video game players, 798-99; vs. night

of, 100; and genetics, 304; and growth

terrors, 117; waking distress, 248

hormone release, 617; heartbeat rhythm

Night terrors: dopamine (medication) as¬

during, 71; and hippocampal cell pro¬

sociation, 237; in Hicks’ dream divi¬

liferation, 628; and illusory content in

sions, 321; vs. isolated sleep paralysis,

dreams, 342-43; linguistic content of

366; vs. nightmares, 117; in young

dream reports, 653; and mouse stud¬

children, 132

ies, 306-7; and napping, 436; and neu¬

“NIghtwalk: A Dream Phantasy in Photo¬ graphs” (Man Ray), 494 Nocturnal frontal lobe epilepsy (NFLE), 147-48, 481-84

rofeedback, 456; neuroimaging and, 293, 295, 597-98; and night terrors, 117, 132; and overgeneral memories, 476; regulation of sleep and wake sys¬

Nocturnal seizures, 556, 693

tems, 539-40; relative to sleep quota

Noise sensitivity, and depth of sleep,

databases, 149-50; and reptilian sleep,


260-61; and sleep problems, 456; of

Nondeclarative memory, 688-89. See

songbirds sleep, 596; transcranial direct

also Sleep, memory, and dreams

current stimulation, 791; and VIP, 250.

Noninvasive techniques in dream studies,

789-92 North American Indians animal dreams, 38 Norton, M. I., 77

See also REM-NREM dream content

specializations; REM (rapid eye move¬ ment) sleep Nwapa, Flora, 391

Nostalghia (film), 196

NREM arousal parasomnias, 148 NREM (non-rapid eye movement) sleep:

Obesity, and sleep, 590, 619-20; alexithymia issues, 25; cardiometabolic

adolescents vs. elderly people, 21; and

risks, 602-3; children’s issues, 346,

alcohol use, 23-24; and apneas, 148;

410; endocrine system involvement,

and arthritis patients, 594; awaken¬

630; obstructive sleep apnea issues,

ings protocol, 65-67; basics of sleep

101, 168, 258, 468-69; quality of life

recordings, 69; and behavioral ecol¬

issues, 529; women’s issues, 470. See

ogy, 263; and brain energy balance,

also Metabolic syndrome

Index Obesity-hypoventilation syndrome, 535. See also Obstructive sleep apnea


OSA. See Obstructive sleep apnea (OSA) Osteoarthritis (OA), 594

Objective and subjective dreams, 467-68

Othello (Shakespeare), 585

Obstructive sleep apnea (OSA): and

Our Dreaming Mind (Van de Castle), 37,

aging, 638-39; and arthritis, 593;


CPAP treatment for, 148, 167-69; and

Overgeneral memories, 473-77

diabetes, 468-70; epilepsy correlation,

Ovid (author), 278

147-48; and heart failure, 636; and iso¬ lated sleep paralysis, 366; risk factors

Pabst, G. W„ 130

for hypertension, cardiac conditions,

Pachamama Alliance, 4

167-68; and sleep medicine, 101; and

“The Pains of Sleep” poem (Coleridge),

teenagers, 643. See also Sleep disor¬ ders and dreaming Obstructive sleep apnea (OSA), metabo¬ lism and hormones, 468-71 Obstructive sleep apnea syndrome (OSAS), 258-59, 303, 643, 647

509 Pandya, Vishvajit, 191-92 Panic disorder, 463, 692 Pankejeff, Sergei, 197 Pannier, Wendy, 105, 325 Paperhouse (film), 129

Odyssey (Homer), 35, 49, 278

Paprika (film), 129

Oedipus the King (film), 130

Parapsychology and dreams, 479-80

Ojibwa tribe, 190

Parasomnias, 148, 351, 715-16; coexis¬

Old Kingdom (Ancient Egypt), 33

tence with epileptic seizures, 148; de¬

Olfactory stimuli and dreams, 471-73

fined, 481; effects of medication, 236;

On Divination through Sleep (Aristotle),

and nocturnal frontal lobe epilepsy,


481-84; NREM arousal parasomnias,

On Dreams (Aristotle), 613

148; from television viewing, 411. See

Oneirocritica (Interpretation of Dreams)

also Incubus/succubus; Sleep terrors;

(Artemidoris of Daldis), 32, 50-61, 352, 422, 423 Oneirocriticism, 389-90, 422 The Oneirocriticon ofAchmet (10th-

century book on dreams), 390

Sleepwalking Parintintin (Amazonian Brazil people), 191, 192 Parkinson’s disease (PD) and sleep,

678-81; actigraphy measures, 5-6; and

Ongis of Little Andaman Island, 192

alexithymia in renal disease, 29; cog¬

On Interpretation of Dreams (Antiphon-

nitive disorders of, 681; depression in,

tes), 611

681; effect on dream studies, 99; ex¬

On Regimen (Hippocrates), 51

cessive daytime sleepiness in, 679-80;

On Sleep and Waking (Aristotle), 613

hallucinations in, 681; insomnia in,

“On the Nature of Dreams” (Jung), 81

679; periodic limb movement disorder

“On the Relation of Analytical Psychol¬

in, 680; RBD association with, 101,

ogy to Poetry” (Jung), 509

214, 554, 556; and REM sleep behav¬

Open-access dream archives, 141

ior disorder, 101; and restless leg syn¬

Open Your Eyes (film), 129

drome, 680; sleep and hallucinations,




Index 681; sleep disorder breathing and sleep

leg syndrome, 101-2. See also Medica¬

apnea in, 680

tions, effects of on sleep and dreaming

Parliament of Fowls (Chaucer), 508

Parrott, A. C., 233, 234 Partial sleep deprivation, 485-86, 601; behavioral effects, 485-86; individual differences, 486; physiological inflam¬ mation caused by, 685; psychological effects, 486; recovery, 486 Partridge, C. P„ 17-18 Patient Health Questionnaire (PHQ-9),

202 Paulus, W„ 791

Phase response curve (PRC) measures,

121 Phasic ponto-geniculo-occipital/pontine wave (PGO/P-wave), 487-90 Phillips, Maggi, 391 Philosophy of mind, and dream charac¬ ters, 490-93 Philosophy of the Implicit (Gendlin), 85

Photography and dreams, 494-95 Phylogenetic comparative methods and sleep, 495-97

Pearson, Cynthia, 375, 376

Phylogeny of sleep, 152-53, 497-503

Peck, Gregory, 130

Phylogeny of Sleep database, 504-6

Pediatric Daytime Sleepiness Scale

Physiological influences (in acute sleep

(PDSS), 643-44

deprivation), 11

Periodic Limb Movement Disorder, 680

Piaget, Jean, 508

Periodic limb movements, 62, 552, 638,

The Picture (poem), 143

646, 649-50, 679-80

Pietrowsky, R., 235

Peris, Fritz, 308-9, 314

Pillows of Bedouins, as sleep aid, 75

Personality disorders, 194, 463, 524, 545,

Pirona, A., 233, 234

607 Personality traits: effects on dreams, 166; and incorporation of experience (PERS), 166; sleep, dreams, and per¬ sonality, 652-54

Pittsburg Sleep Diary, 641 Pittsburg Sleep Quality Index (PSQI), 29-30, 507, 650, 694, 706 Plasticity, metaplasticity, and sleep,


Peruvian animal dreams, 38-39

Plato, 142, 341,612-13

PET (positron emission tomography), 72,

Play and the dream, 507-8

96, 162, 293, 597 PGO. See Pontine-geniculate-occipital (PGO) cortical spikes PGO waves, 193, 271-74 Pharmacological studies, 96-97; ADHD

Poe, Edgar Allen, 278 Poetry and dreams, 125, 142-43, 183,

421,508-10 Polycystic ovarian syndrome (PCOS), and obstructive sleep apnea, 470

children and dreaming, 62; brain en¬

Polyphasic sleep cultures, 189

ergy and metabolism, 96; depression

Polysomnographic (PSG) sleep studies,

and dreaming, 200; disturbed sleep and

4-6; arthritis studies, 593-94; cardio¬

PTSD, 216; dreaming altered by medi¬

respiratory polysomnography, 71-72;

cations, 413-14; historical background

and mild cognitive impairment, 618;

of sleep medicine, 101-2; and REM

of PTSD, 510; of RBD, 214, 550;

sleep behavior disorder, 553; restless

short sleep assessment, 589; and sleep

Index duration, 620; Types II-IV portable

during pregnancy studies, 417; Na¬

equipment, 511

tive American beliefs, 19; relation to

Pontine-geniculate-occipital (PGO) corti¬ cal spikes, 83 Portable monitoring of sleep, 510-11. See also Polysomnographic (PSG) sleep


dreaming, 1-2. See also Fetal sleep; Fetal yawning Pregnancy dreams, 518-19 Primary disorders of hypersomnolence and dreams, 520-21

Porter, Edwin S., 127-28, 197

Primitive sleep, 261, 615-16

Positron emission tomography (PET),

PRL (prolactin), 249-51, 281, 625

72, 96, 162, 293, 295, 452, 513, 555,

Problem solving in dreams, 182-85

597- 98, 734

Profile of Mood States, 157

Posterior cingulate cortex, 294, 452, 559, 598- 99


Prophetic dreams, 800-801 Protestant Reformation, 78

Posttraumatic nightmares, 106, 117-18

Protoconsciousness theory, 269

Posttraumatic stress disorder (PTSD),

Psoriatic arthritis (PsA), 594

118; disturbed sleep and, 215-17; and

Psychiatric diagnosis and dreams, 522-25

insomnia, 606; lucid dreaming rescript¬

Psychiatric disorders: and autism, 606-8;

ing for, 405-6; nightmares as part of,

nightmares, sleep and, 606-8; and the

270, 401, 463-64; PSG studies of, 510;

transdiagnostic perspective, 704-6

rescripting approach to nightmares, 106; and sleep disturbances, 650-52. See also Veterans of foreign wars,

sleep problems Poulin, J., 607 Powell, R. A., 227-28 The Power of Movies: How Screen and Mind Interact (McGinn), 126

PRA (plasma renin activity), 624 Prader-Willi syndrome (PWS), 304 Precognitive dreaming, 256-57, 512-13

Psychoactive substances, in Bedouin tra¬ dition, 73-74 The Psychoanalysis of War (Fornari),

288 The Psychodynamic Diagnostic Manual,

524 Psychological primaries (colors), 145 PTSD. See Post traumatic stress disorder (PTSD) Purunas (Hindu literature), dream stories, 801

Predictive dreams (of African Ameri¬ cans), 20 Prefrontal cortex in dreaming, 91 -92, 446-47, 513-17 Pregnancy: Aboriginal women and dreaming, 1; African dreams of pre¬ diction, 20; effect of SWS on fetus,

Quaker culture and dreams, 527-28, 565 Quality of life and sleep disorders in chronic kidney disease, 528-30 “Queen Katherine’s Dream” (painting) (Blake), 196 Quiet sleep, 280, 495, 640, See also

280-81; female influence of gender,

NREM (non-rapid eye movement)

263; and genetic conflict, 264-65; go¬


nadal hormones and REM sleep, 252; Korean dream traditions, 55; melatonin

Qur’an and dreams, 75-76, 364-66, 530-31,541-42





Rabid Eye graphic novel (Veitch), 311

REM-NREM dream content specializa¬

Rabinowe, Victoria, 53

tions, 542-46 REM (rapid eye movement) sleep: ab¬

Ramanujan, Srinivasa, 185 Ramesside Period (Ancient Egypt), 34

normal REM sleep and narcolepsy,

Rare Bit Fiend comic strip, 310

440-42; across the lifespan, 546-50;

Ray, Man, 197, 494

aging effects on, 637; association to

RBD. See REM sleep behavior disorder

CST, 180-81; association with vivid

Reality, logical structure of dreams and

visuomotor perception, 8; and attach¬

their relation to, 394-96 Recalling dreams, absence of, 457-59. See also Dream recall

ment theory, 267; and autism, 608; awakenings protocol, 65-67; and be¬ havioral ecology, 263; and bizarre im¬

Rechtschaffen, A., 164

agery and thought in sleep waking,

Recordings of sleep, basics, 69-72.

83-84; and blindness studies, 238-39;

See also Actigraphy; EEG (electro¬

changes during adolescence, 657;

encephalography) measures; EMG

characteristics of, 69, 71; and charac¬

(electromyography) measures; EOG

ters in dreams, 110-13; and children’s

(electrooculogram) measures; NREM

dreams and nightmares, 114-16; and

(non-rapid eye movement) sleep; REM

colors in dreams, 144; as component of

(rapid eye movement) sleep

sleep definition, 193; convergent evo¬

Recovery from acute sleep deprivation, 11

lution in mammals and birds, 169-71; and costly signaling theory, 268; and

Recurrent hypersomnias, 520

CRH, 331-32; and deprivation recov¬

The Red Book (Jung), 373, 377-78,

ery, 11; and depth of sleep, 203; de¬

379-80 Regulation of sleep and wake systems,


scribed, 495; in different mammals, 149-50; and disconnection from ex¬ ternal environment during dreaming,

Reid, Thomas, 403

206-7; discovery of, 7, 133, 208-9;

Reklaw, Jesse, 147, 311

and disruptions of in PTSD, 216-17;

Religion and dreams, 123-24, 540-42.

and dream characters, 110-12; and

See also Buddhism; Christianity/Chris¬

dream consciousness, 139, 159-60;

tian Church; Judaism

and dream function, 298; dream mean¬

Religious symbolism in dreams (Christian Church), 123-24 REM dreaming intrusion: and hypersom¬

ing studies, 139; and dream recall, 94; and Ecstasy (MDMA) users, 233-34; effects of anti-depressants on, 200;

nias, 520; and ISP, 367; and narco¬

and endocrinology of sleep, 249-54;

lepsy, 211-13, 437; and orexin levels,

erections and, 208-9; and fetal REM

252, 450; and PWS, 304; and RBD,

sleep, 269, 280; and genetics, 304; and


handedness, 321-22; heartbeat rhythm

REM muscle atonia, 69, 100-101, 211, 214, 280, 367

during, 71; and hippocampal cell pro¬ liferation, 628; hypnagogic dreams vs.



REM dreams, 328; and illusory content

21-22. See also Brain networks and

in dreams, 342-43; and involuntary

sleep; Neuroanatomy of dreams; Neu¬

nature of dreaming, 364; and journal¬

roanatomy of REM sleep and depres¬

ing of dreams, 373; linguistic content

sion; Neurobiology of psychoanalysis

of dream reports, 653; and lost dream

in wake and REM sleep; REM-NREM

recall, 459; and lucid dreaming, 91-92;

dream content specializations

in mammals and birds, 498; meaning

REM-sleep atonia, 441

studies, 139; medication influences,

REM sleep behavior disorder (RBD),

413-14; and medications effect on,

101, 550-56, 680-81; altered dream

235-37; and mild cognitive impair¬

content, 215; and dementia with Lewy

ment, 618; and mouse studies, 306-7;

bodies, 101; and dissociated states,

and napping, 436; and narcolepsy,

211; distinct dream content associated

437-38; negative REM dream, 476;

with, 213-15; and narcolepsy, 440; and

neuroimaging and, 294-95, 597-98;

Parkinson’s disease, 101; in Wilson’s

and nightmares, 117-18, 461-62; and

disease patients, 682-83

overgeneral memories, 475-76; PET studies of, 162; PGO waves during, 271; precognitive dream studies, 512; and prolactin, 249-51; and psychiat¬

REM sleep behavior disorder or somnambulism-like ghost tales, 708, 710 REM (rapid eye movement) sleep in criti¬ cally ill patients, 533-36

ric disorders, 692; regulation of sleep

REM sleep properties, 557-58; as neuro-

and wake systems, 539-40; regulation

biological endophenotypes of schizo¬

role of serotonin, 207, 233, 237, 414,

phrenia, 558-60

440, 539, 578, 580-82; and relation to Cl intensity, 110; relative to sleep quota databases, 149-50; REM sleep

REM sleep-relat