Corollary Discharge, The Forgotten Link. Remarks on the Body-Mind Problem (Feldenkrais perspective) 9780918236098, 0918236096

Citation preview

CoROLLARY DISCHARGE, THE FoRorrrEN LINK Remarks on the body-mind problem Yochanan Rywerant

Freeperson Press

Novato, California

Copyright © 2008 Yochanan Rywerant All rights reserved. No portion of this book may be reproduced, by any process or technique, without the express written consent of the author and publisher. ISBN 0-918236-09-6 ISBN 978-0-918236-09-8 First published in 2008 Freeperson Press 1516 Grant Ave., #212 Novato, CA 94945 www .somaticsed.com [email protected] Printed in the United States of America Cover design by Satri Pencak Typesetting & book design by TBH Typecast, Inc.

Contents

Foreword by Eleanor Criswell Hanna, Ed.D. Preface Acknowledgments I. 2. 3. 4. 5. 6. Z 8.

Introduction H. L. Teuber and Corollary Discharges M. Feldenkrais and Relative Conjugate Movements Habitual and Non-Habitual Patterns of Action Corollary Discharge in Everyday Life The Self's Boundaries Impairment and Rehabilitation Conclusion: The Body-Mind Link Reconsidered

References

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Foreword Eleanor Criswell Hanna, Ed.D.

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HEN YocHANAN RvwERANT asked me to publish his monograph, Corollary Discharge, The Forgotten Link, I was delighted and honored. The term corollary discharge first caught my attention in a lecture by Rywerant in the early 1990s. Later I read references to it in Vernon Brooks's The Neural Basis ofMotor Control. The concept of corollary discharge, and the related term efference copy, have intrigued me over the years, but they have remained somewhat elusive as I pondered motor mechanisms and worked somatically with myself and others. In this monograph, Rywerant gives us a clear understanding of corollary discharge, a neural mechanism that is so important for our effective movements. Rywerant begins with an introduction to corollary discharge. A history of the discovery of corollary discharge by H. L. Teuber, a neuroscientist from the Massachusetts Institute of Technology, Cambridge, Massachusetts, in the 1960s and the exploration of it by other neuroscientists follows. Rywerant discusses the use of the understanding of corollary discharge in Feldenkrais's relative conjugate movements (a function named by Rywerant). The role of corollary discharge in habitual and non-habitual patterns of action is discussed. Then these understandings are applied to

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everyday life. The boundaries of the self are explored from the perspective of corollary discharge. Next, the situation of impairment and rehabilitation with regard to corollary discharge is discussed. In his conclusion, Rywerant reconsiders how corollary discharge relates to the link between the mind and body. What is corollary discharge? Corollary discharge is a discharge from the motor system to sensory systems regarding intended voluntary movement or postural change, "preparing those sensory systems for changes that will occur as a result of the intended movement:' Because corollary discharge is unconscious, subliminal, or below the level of our awareness, it is valuable to be aware of what it is, why it is important, and how it enhances our function. Rywerant says, "The corollary discharge is the mechanism by which a nonhabitual pattern of action changes gradually into being more habitual:' Corollary discharge and efference copy are related concepts. Efference copy is a special case of corollary discharge. According to Webster's Ninth New Collegiate Dictionary, corollary refers to "something that incidentally or naturally accompanies or parallels:' Discharge means "to relieve of a charge, load or burden:' Efference is a term for information moving out from the central nervous system to cause muscle contractions or glandular secretions. Efference copy is a copy of the expected sensations that may arise because of motor action. The copy is sent to the sensory cortex to prepare the organism to ignore self-generated sensations. Therefore, Rywerant says, "the consequences of the intended actions are already anticipated:' My sense of efference copy is that as a movement plan is created by the brain, information is sent to all parts of the body notifying it of what is to come and preventing interference with the activities. All too often we do not consider this necessity in our motor planning. Frequently, the person interferes with the very action he or she intends. This is very common in the unnecessary co-contractions that people frequently exhibit that interfere with ease of movement.

Foreword

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With the sense of corollary discharge expressed by Rywerant we can see the importance of developing the learned corollary discharge for skilled movement. The athlete or musician has a highly developed capacity for this. This is a huge area of untapped potential for all of us. In the various awareness-enhancing disciplines, such as the Feldenkrais Method, the person may be instructed to recover awareness of reafference or to decrease the prior editing effect of the efference copies. This deliberate allowing of awareness of the sensory feedback from one's own movements permits the person to remain aware of the results of his or her movements. This increases the complexity of the sensory experience and allows the person to appreciate more of the sensory world. Rywerant brings his mastery of the field of mind-body education to bear in understanding a very present, but little understood aspect of neuromuscular function. It brings this sometimes subliminal aspect of our worlds to our conscious awareness both for the appreciation of the function and to begin to make more conscious use of it. The expansion of our awareness of corollary discharge has huge potential for enhancing motor functioning. In writing this foreword, I have pondered corollary discharge again and again. Finally, with a thorough study of Rywerant's monograph, I understand the concept on a much deeper level. I have grown to appreciate the role of corollary discharge in our ongoing behaviors. The benefit of Rywerant's monograph is that it is brief, well written, and brilliant. That is the way Rywerant writes, as seen in his previous books The Feldenkrais Method: Teaching by Handling and Acquiring the Feldenkrais Profession. His writing style is well organized, comprehensive, and concise. He writes abou~ what he knows. He was originally a physicist and a teacher of physics. He brings his knowledge of physics into his understanding of the body. He began studying with Feldenkrais in 1952 in the Awareness Through Movement classes in Tel-Aviv. Trained by Moshe Feldenkrais in Israel in the first professional training course, which began in 1969, he was one of the original

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Feldenkrais assistants. He worked side-by-side with Feldenkrais in the Feldenkrais Institute in Tel-Aviv with pupils from all over the world. He assisted Feldenkrais in the two training programs in the United States, San Francisco and Amherst. With Feldenkrais's death in 1984, Rywerant began conducting professional training programs. Since his original training with Feldenkrais, he has practiced the Feldenkrais Method with thousands of pupils and conducted basic and advanced training programs around the world. Currently, his primary teaching of the Feldenkrais Method is advanced training programs in Israel and Switzerland. May you enjoy the guidance of Yochanan Rywerant, a master teacher, as you explore the world of corollary discharge.

Preface

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the lay reader about Certain aspects of the human brain's functioning that are involved in learning, habituation, control of actions, and, eventually, rehabilitation. I am not intending to present here a learned scientific article or paper, but rather to bring into focus a continuously occurring event or activity within our brain called "corollary discharge" that usually accompanies intentional actions. There will be a few conclusions as well, some in matters of principle, like certain understandings concerning the mind-body gap, and some of a practical nature. The latter will draw attention towards some everyday activities seen in this context, and also present insights and experiences attained in the framework of the Feldenkrais Method, which addresses people, either through verbal advice or through gentle manipulation, with the purpose of enhancing their adaptation to limiting, or adverse, circumstances. The method attempts to achieve this by increasing the awareness of their self-produced actions and expanding their self-images so that they might include alternative options for acting. HIS MONOGRAPH ADDRESSES

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Acknowled9ments

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my respect to Dr. Eleanor Criswell Hanna for publishing this monograph and for adding an exceptional foreword to it. Thanks to Marsha Calhoun for copyediting; Satri Pencak for the cover design; TBH Typecast, Inc., for book design and typesetting; and McNaughton & Gunn, for printing and binding and for helping this monograph come out so nicely. Y THANKS AND

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CHAPTER ONE

Introduction

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to express in words some state or happening within ourselves, we usually use words taken from two areas: the body (as when we name parts of the body and their relationship to each other) and the mind (as when we describe what we sense, what we know, what we feel, and what we remember, but also what we think, what decisions we might make, and what our fears, our doubts and our hopes might entail). In philosophy, we have what is called the dualism of impression and reflection, of knowledge and belief, of body and soul, all this going back to Plato and continuing to the present day. Our modern languages provide us with words and concepts defined for these two areas: mind and body. We might even have some difficulty in finding words that could express a unity that comprises both mind and body. One nice exception is the word "self:' In the biological sciences, we have anatomy, physiology, neuroscience, etc., that describe ways of functioning and acting in terms of bodily parts and concepts taken from the realm of the material world. These include muscles, joints, nerves, and diverse parts of the central nervous system (CNS); on a smaller scale, the description includes neurons (neural cells), their constituent parts (nuclei, etc.) and connections (synapses), nervous impulses, and neurotransmitters. HEN wE WANT

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Then we have psychology, sociology, etc., using concepts taken from the realm of thoughts, feelings, beliefs, and memories: the realm of the spirit. Of course, the question arises: since the body and mind seem to influence each other, how could one describe the causal link between the two realms? What precisely is the connection between an injury I endure and the feeling of pain that comes with it? What is initiating the nervous impulses that move my muscles and joints when I intend to bring a glass of water to my lips? Clearly, there is a "gap" between the physical and the mental; we would expect science to explain, or rather describe, what is going on. Scientists of several specialties have turned their attention towards the problem and, especially during the second half of last century, two areas of investigation have come into the forefront of interest. One deals with the question of memory. How is memory encoded into the brain? How do we recognize faces? Could we describe "meaning" in objective terms? The other deals with the question of consciousness. Is there such a thing? How do we know that we know? Is consciousness just a byproduct of happenings in the brain, as they are described in material terms? Or is consciousness a special phenomenon, connected to several of the self's attributes, such as self-awareness, intentionality, morality, and responsibility? Books and articles have been written on these subjects, and symposia have been convened with participants from several related professions, including physiologists, neurologists, psychologists, ethologists, philosophers, and cyberneticists. The special purpose was to elucidate if there is any way to bridge the "gap" between the mental and the physical, between consciousness, memory, perception, and other cognitive functions and the physiological or neurophysiological aspect of those functions. Francis Crick and Christof Koch I suggested that an investigation should start on a better-known aspect of brain function, Crick, F., & Koch, C. (1992). The problem of consciousness. Scientific American, 267, 152-159.

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Introduction

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the visual system, "because humans are very visual animals and because so much experimental and theoretical work has already been done on it:' Such an endeavor is likely to yield a possible scientific description of consciousness. An alternative to this idea could be to investigate the way we control our actions and thoughts by consciously monitoring them. The function of "monitoring the self" has an advantage in that this function is going on during most of our waking state, and it is amenable to everybody's introspection. It should be said here that the scientific world, especially during the last half of the twentieth century and the first few years of this century, has gradually been recognizing introspection as a valid process of scientific investigation.

CHAPTER TWO

H. L. Teuber

and Corollary Dischar9es

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held in Rome at the Vatican Science Academy in 1964 on the subject of "Brain and Conscious Experience," the late Professor Hans Lukas Teuber2 of the Massachusetts Institute of Technology in Cambridge, Mass., put forth the idea of corollary discharge. There is the subjective awareness of experiencing directions in space (a left, a right, above, below); moving the eyes or tilting the head leaves the perception of the space invariant. There is also the awareness of the space behind (the absent space), and hence, we have the ability to make maps and plans. Teuber proposes that the three aspects of spatial order are distinct and should be considered separately: the immediate perception of visual space, the mechanism of compensation for voluntary changes in posture, and the level of representation of spatial relations not immediately given (as defined by the environment, hence showing the ability involved to find routes and make maps). The distinction of these aspects can be shown by considering their selective vulnerability to different cerebral lesions: injury of the occipital lobes interferes with presentation, injury of the frontal lobes interferes with compensation, and injury of the parietal lobes interferes with representation (p. 183). N A SYMPOSIUM

2 Teuber, H. L. (1966). Alterations of perception after brain injury. In J. Eccles (Ed.), Brain and conscious experience (pp. 271-276). Berlin, Heidelberg, New York: Springer.

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Teuber assumed that the appropriate compensation for head tilts or head movements has to be provided by a central mechanism ("central" meaning here "of the central nervous system"). Any voluntary movement or change of posture involves, simultaneously with the efferent discharges to the peripheral effectors, a central discharge from motor to sensory systems, the corollary discharge, preparing those sensory systems for the changes that will occur as a result of the intended movement. For example, any intentional eye movement obvieusly moves certain contours over the retina, but leaves the spatial order of perceptign undisturbed, because the corollary discharges that accompany the motor impulses to the eye muscles preset the visual system to anticipate the changes and produce a compensatory action that keeps the perception of spatial order invariant. By contrast, pushing your eyeball with your finger, without involving the eye muscles, elicits the perception that the visual scene jumps (p. 198). Versions of an "outflow theory"-about the role of eye movements in perception-were formulated by Holst and Mittelstaedt, and also by R. W. Sperry, by 1950. Teuber intended to give these notions "the broadest possible meaning," so much so that the presence or absence of a corollary discharge would then serve as a physiological marker of whether a movement was voluntary or involuntary, self-produced or reflex (p. 198). A series of experiments has been done that underscored the importance of distinguishing active from passive movement. Teuber gives an account of an experiment in which a person was made to wear prismatic spectacles that displaced all visual input by 15° to the left. In this experiment, it was found that in the beginning, the person will misreach for objects by 15° to the right of their true location. However, after an hour or so, during which the person walks actively in an optically structured environment, a compensation for the visual displacement occurs. Reaching under visual control has now become accurate again. After removing the spectacles, a misreaching again occurs, this time in the direction opposite to the former one, but this disturbance may

H. L. Teuber and Corollary Discharges

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last only a few minutes. On the other hand, if the wearer of the spectacles moves passively, for example, by being pushed around in a wheelchair for an hour, no compensation for the prismatic spectacles will occur. The perceived contours sweep over the person's eyes in the same way as in the first instance, but the absence of self-produced movement, and hence, the absence of corollary discharge, prevents the reorganisation of the visuo-motor function (p. 201 ). Teuber assumes that during the first months of life, a transition occurs from various automatisms towards voluntary movement and the performing of various actions under visual control. This requires the spatial order of perception to remain invariant during changes of posture (p. 203). Other neurophysiologists have used the term "efference copy" to refer to corollary discharge because, together with the outgoing (efferent) impulses from the motor centers to the peripheral effectors (the muscles), a "copy" of those impulses goes to the respective sensory brain centers, so that the sensory consequences of the intended action are already anticipated. One may sum up what Teuber wrote about the meaning of corollary discharges in their "broadest possible" sense: a) they enable the sensory centers in the brain to anticipate the consequences of self-produced actions, b) perceiving the invariance of the spatial order of perception is accomplished by a compensating mechanism, c) corollary discharges are learned by experience, d) corollary discharges have a special role during the first few months of the individual's life, and, finally, e) they determine, by their presence or absence, whether a movement is voluntary (intentional) or involuntary (reflex). It is interesting to mention that contemporary neurophysiology largely ignores the notion of corollary discharge (or efference copy), despite the fact that neural pathways that can assume these inner connections have been established in the brain, and despite the fact that those connections might indicate a way to clarify certain aspects of the body-mind issue. After all, you have

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here a controllable connection between sensation, perception, and intention. Anyway, I am going to present two (out of several) instances that consider corollary discharges as facts that deserve to be taken seriously. R. H. S. Carpenter3 presents a control system that involves modification of behavior through experience, using internal feedback. The notion of "efference copy" explains that one can form an advance estimate, a predicted outcome, of what position a body part is going to adopt in respon~e to any particular pattern of (intentional) motor commands that is sent to it. Such an estimate is formed entirely within the brain, and it may well be available long before any feedback from the actual movement has found its way back from the periphery. The desired result is then compared not with the actual result, but with the predicted result. This predicted result in turn is derived by sending a copy of the motor commands (the efference copy) to a neural model of the mechanical properties of the body and of the outside world, which is used to predict the probable result. Later, the actual result may also be compared with the predicted one, and any errors may be used to correct the model itself, continuously improving the accuracy of the predictions. Learning motor skills becomes a matter of learning to predict the behavior of one's own body (pp. 237-239). Walter J. Freeman4 refers to the goal-directed actions that the brain constructs; the brain also primes the sensory cortex to select the sensory perceptions that are predicted as the consequences of the impending actions. This is a central process that he calls preafference, which is the basis for what we experience as attention and expectation. The sensory cortices can thus predict how the performed actions might change the relation of our senses to the world. The messages are the above-mentioned corollary discharges. They help us to distinguish between changes Carpenter, R. H. S. (1990). Neurophysiology. London, Melbourne, Aukland: Edward Arnold. 4 Freeman, W. J. (2000). How brains make up their minds. London: Phoenix.

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in the environment and apparent changes that are due to the intentional movements of our bodies. The somato-sensory cortex also receives messages from the muscles and joints, which confirm whether an intended action has been performed. This feedback process, called proprioception (as well as interoception), coming from the internal organs, and exteroception, coming from the world, connect brain and body, whereas preafference resides entirely within the brain. Preafference enables us to imagine what things may be like, if or when they come (pp. 44-45). Preafference precedes feedback by proprioception and interoception. The corollary discharges convey information about what is to be sought by looking, listening, reaching, etc., and the returning afferent discharges convey the current state of the search. When the expected stimulus is there, then we experience it; when it is not, then we imagine it (p. 145). Freeman puts the emphasis on this preconfiguration involving preafference and sensory recursion, considering this to be the basis of search, perception, and intentional action.

CHAPTER THREE

M. Feldenkrais and Relative Conjugate Movements

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in the preface, the Feldenkrais Method addresses people in group sessions through verbal advice, by proposing that they perform easy actions, while drawing attention to the sensory feedback that comes with these actions. In individual sessions, the Feldenkrais Method addresses people through gentle manipulations, also with the purpose of enhancing their adaptability to limiting or adverse circumstances. The method attempts to achieve this by increasing their awareness of self-produced actions, and expanding their self-images, so that they might include alternative options for acting. We can say that the Feldenkrais Method is a dialog between teacher and pupil, mostly on a sensory level, on the issues of intention and action. We have the ability to plan self-produced intentional action, and we can decide to postpone its realization or even to give it up altogether. When performing it, we can monitor it, and change its course if it seems appropriate to do so. We have, in other words, an image of any intentional action that precedes that action, and, while that action is being carried out, we can follow it and compare any intermediate phase with the intended result, and perhaps correct the doing, if needed. One could say that the ingredients (or components) of an intentional action are several. We are considering them here from S ALREADY MENTIONED

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the functional point of view, leaving out the more difficult issue of their localizations in the central nervous system. The components are as follows: • The above-mentioned image of action (encoded now somewhere in the planning part of the brain). • The decision to start the action proper, with the activation of the executive parts of the self: the motor cortex, etc., and the outgoing (efferent) nervous impulses reaching the muscles. • Any emotional state linked with the action, whether anticipated or emerging while the action is carried out. • The corollary discharge (efference copy), informing (presetting) the sensory centers about the feedback that is going to come with the realization of the action. • Movement, produced by the relevant muscles, while they obey the efferent impulses that have reached them. • The sensory feedback that informs the sensory centers, as well as the planning center, about the state of affairs while the action is going on, and, eventually, the perception of the environment as invariant. • The decision of the planning (monitoring) center to compare this upcoming image with the original image of action. • If needed, the planning center changes something in the efferent impulses, in order to diminish a possible deviation between the two images (negative feedback); that last component might relate to any object connected with the action, as well as to the orientation of the self within the environment, while coming nearer, for example, to such an object or to a certain part of the environment, or avoiding it, as the case might be. • The feed forward, which is the beforehand information that leads to control of action, one kind being the abovementioned image of action that precedes it, and the other

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kind being the information that stems from the immediate environment and/or from the self's bodily parts relevant to the activity. • The parts of the environment that are connected to the self by action (energy exchange) or by information-flow should also be considered as components of the image of intentional action. The above-mentioned components of intentional actions emerge in one assembly. Some appear simultaneously, some subsequently, whether they stem from different realms (body and mind) or not, whether the action is a trivial, everyday action or a newly planned and more important one. They enable the self to monitor and to control its actions and to realize its intentions. Sometimes an image of action is incomplete, perhaps not including detailed participations of certain parts of the self or appreciation of the effort involved, distances (fixed or changing) between parts of the self, or a required change of supports, etc. A more complete image might increase the versatility, adaptability, and efficiency of the action. Hence, drawing the attention of the person to details of that kind, while performing certain easy actions, will be perceived as a welcome help. One category of details that might be incomplete is the sensory feedback that comes with the action. This incompleteness might be due to a lack of attention, or to the fact that certain parts of a totality of sensory information are just "filtered out," that is, they do not reach the conscious parts of the self. One could say the same about the anticipation of the sensory outcome of the ensuing action, as when the person doesn't know what precisely to expect. However, after some repetitions, the anticipated sensory outcome is perhaps learned (in other words, no surprises anymore!), and it becomes included in the image of action that precedes the action. The corollary discharge is the mechanism by which a nonhabitual pattern of action changes gradually into being more habitual.

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The sensory outcome of the action might sometimes have an inhibiting character, as when it provides a sense of inability or inadequacy, an unusual effort, danger (real or imagined), or even pain. After some repetitions of that action, an anticipation of that kind will become part of the image that precedes the action, and, hence, be a hindrance to that action, sometimes stopping it altogether. Dr. Feldenkrais, in the framework of his method, showed a possible way to solve such a difficulty. To circumvent the restricting anticipation, he used what I cal.led a relative conjugate movement, which is simply moving a proximal part of the body relative to a motionless distal part (movement B), instead of moving that distal part relative to the said proximal part, which is motionless (movement A). The two movements (A and B) use the same joint, but are part of different images of action, the latter (A) attempted habitually and possibly being connected with restricting anticipations, whereas the former (B) is done in a nonhabitual way and is devoid of such restrictions. When the B movement is perceived by the teacher as having been allowed and accepted (in other words, cortically controlled), the teacher can propose the original A movement. The pupil might now perceive-even with some surprise-the ease of doing the action without sensing the habitual restriction. If it happens that a structural limitation is causing the restriction in movement, then this approach might not work. I should say here that in the framework of the Feldenkrais Method, there is no attempt to overcome structural limitations. One has to know them and respect them. It is an empirical fact that, with any voluntary action that uses movement, the participation of the distal parts of the self (hands, feet, head, lips) is more clearly represented in the image of action than is the participation of the proximal parts (pelvis, chest, hip joints, shoulder joints). This circumstance is applicable to relative conjugate movements, and with some other approaches as well. Let us look at one example in which the idea of relative conjugate movement is applied. A man had difficulty in raising his right

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arm overhead; he complained of pain. The teacher invited him to lie down on a couch on his back. The teacher then gently took the man's right arm by the elbow and moved it overhead, only so far as it went easily, up to an obtuse angle between the chest and the upper arm. The next step was not to increase that angle by lowering the elbow to the couch, but instead for the practitioner to hold that elbow fixed in space with one hand, and to lift the right shoulder blade, slightly away from the couch, with his other hand. Doing this repeatedly, the teacher might eventually sense that this movement was starting to get easier. The teacher could then lower the shoulder blade towards the couch while lowering the elbow, which would thus become the new and easy way to act. One might repeat this process, starting from the newly gained situation, and thus achieve another small amount in the extension of the shoulder joint.

CHAPTER FOUR

Habitual and Non-Habitual Patterns of Action

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E MIGHT BE INTERESTED

in changing SOme of Our non-habitual

actions, as mentioned in the previous chapter, into habitual ones. This change occurs in everybody during the early stages of our lives, for example, with activities like using forks and knives, writing, and so many others. When one is performing an action the habitual way, there is no real need to pay attention to certain details that are part of the pattern. These details may include filtered-out items of sensory feedback that come with the action, like participation, or lack of participation, of certain parts of the self in that action. The effort of paying attention to a number of details connected with that action, which is done when the action is still new and non-habitual, might ultimately be spared. This is actually in everybody's interest, and enables us to enact the habitual doing in a more expedient way, perhaps without the preparation or deliberation that we might need before enacting something non-habitual. As an example, let's take handwriting. A child learning to write remembers first of all the form of the letter he is going to write, then chooses the strokes that will form the character, watches to see that the letter will be nicely aligned with the other letters, etc. The adult writer, habitually, will almost ignore much of this and shift his attention towards the whole word, the sentence, and so

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on, and to the meaning or idea that is to be expressed through the writing. On the other hand, if it happens that the adult writer has to write something on a blackboard (for an audience, for example), he might revert his attention towards those above-mentioned elements, having to act differently from his acquired habitual way. Among so many examples that we can take from everyday life, we will consider riding a bicycle. The youngster learning to ride the bicycle pays attention to the way he keeps the balance, how he controls the speed, and how he negotiates a curve. In due time, as he acquires the habit, he ceases to worry about those things while riding, and his attention is free to shift to other aims, like looking around, talking, or speeding on in order to get to his destination faster. On the other hand, if it happens that he is riding within a group of people who are walking around, and he intends to slow down, then he might worry about keeping his balance and avoiding someone by making an appropriate curve. Considering what we said in chapter 3 about the ingredients of an intentional pattern of action, it follows from examples of this kind that with new and nonhabitual patterns, the image of action preceding the action might not have a clear outline. This is connected, for example, with the fact that the participation of proximal parts of the self is barely represented; the corollary discharge, informing the sensory centers about the sensory feedback that comes with the action, is still only tentatively present, or perhaps not present at all. In other words, is any expected outcome really there? Moreover, when perceiving a deviation from the expected outcome, how much change in the response (the "gain"), in muscular effort, for example, will the person need, so that the deviation will diminish, as it is desirable, and the action will not "overshoot"? The self is dealing with the situation by being attentive to these elements, which means that it is using the conscious parts of the brain-the cortical level-in controlling and monitoring the action. With some repetition of the same action, or a similar action, the corollary discharge is learned; it consolidates and

Habitual and Non-Habitual Patterns ofAction

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becomes a regular ingredient of the pattern. Any deviation from the goal will then elicit a controlled change in the effectors, so that the action gets nearer to the goal. Gradually, those elements need less attention, and the control is assumed by a "lower" level of the central nervous system. The term "lower" implies a hierarchy of levels of control: a lower (subcortical) level controls the habitual patterns, but in nonhabitual or changing conditions, the higher level takes over, and full attention is paid to issues that otherwise are left to the care of a lower level. That lower level is, for the time being, repressed, but its control over the action reinstates itself when the self no longer perceives the special conditions. Patterns of action that have been learned in the earlier stages of our lives are more deeply ingrained in the central nervous system, and the corresponding level of control is lower than the level that controls more recently acquired patterns. It is known that after having a stroke, people who previously had the command of several languages sometimes lost their ability to speak any language besides their mother tongue. This can be considered a regression: the higher level of control has been damaged, so a lower level takes over the control. Congenital and hereditary patterns that exist at the time of birth, like breathing, sucking, swallowing, coughing, and the like, are still more deeply ingrained, and so are patterns of defense (such as the actions done to protect the vulnerable parts of the body), all of which derive from the instinct of self-preservation. We can now return to the idea stated at the beginning of this chapter about changing a nonhabitual pattern of action into a habitual one. All learning by the brain amounts, in the end, to the formation of physical connections between neurons, in such a way as to represent the associations that exist in the real world. Memory thus represents the world within our brain. We can distinguish several aspects of the ongoing processes that result in habituation. One is synaptic facilitation. A synapse is a tiny space that exists between the axon of one neuron and

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the dendrite of another, in which those neurons exchange information. Almost all attempts to describe the way memory and the process of learning might be encoded in the brain imply some notion either of synaptic growth (an enlargement of the site of contact between neurons), of strengthening of local synaptic action by neurotransmitter synthesis, or of generation or regulation of new receptor sites (new synapses). Another aspect of the process of habituation is the use that one makes of an action in various conditions and in different contexts. The more one applies the same element of action with a variety of associations and goals, the more this element will be integrated and habituated. As an example drawn from the practice of the Feldenkrais Method, let us suppose that the easier moveability of a client's shoulder blade has been clarified. Very often, this calls for a further integration, so that this new ability will not remain a passing experience. One efficient way to do it is to use the now easily movable shoulder blade for pulling or pushing something in different directions, for pointing in various directions, or for reaching for a high-situated object (or for one's own foot, for that matter). The same can also be done in different positions, such as sitting, standing, or lying down. The more that actions like these, taken from everyday behavior, are tried out, the greater the chance that the easier-moving shoulder blade will be integrated and habituated. A further aspect of the process of habituation is clarifying, while acting, what to expect sensorily (in other words, to learn the corollary discharge). Any nonhabitual pattern of action might be carried out, while certain sensory outcomes, about the acting self or about the immediate environment, are outside one's awareness. The teacher could just divert the person's attention toward details of that kind. By the way, we do this routinely in the framework of the Feldenkrais Method. After only a few repetitions, the sensory details will already be anticipated; in other words, the corollary discharges will become part of the image of action that preceded the action. The action starts to become habitual.

Habitual and Non-Habitual Patterns ofAction

21

As a practical example, we can consider a teacher leading a group of people in an "Awareness through Movement" session. They sit on the floor with their legs to the left and their right hands held a comfortable distance in front of their eyes. The teacher instructs them to turn their hands and eyes a little to the right, only as much as is comfortable without straining, and then to return to the initial position While doing this a few times, they are instructed to observe the places on the wall towards which their right hands are projected. Now, the teacher diverts the students' attention while they are doing the same moves, first to the turning of the neck, then to the movement of the shoulders, then to the change of the floor's pressure that supports the left buttock. All these details might participate now more clearly in the initial turning, or, at will, be prevented from participating as a voluntarily chosen alternative. Ultimately, by observing the places on the wall behind their outstretched hands, the people find that their twists reach further than they did before, even when they are trying to move with the same ease as at the beginning, and the places on the wall behind their hands have shifted an easily detectable amount to the right. This example shows that it is possible for details of the sensory consequences of an action to escape conscious awareness. When one pays attention to them repeatedly, one establishes the anticipation of what is going to happen. In other words, one learns the corollary discharge. Again, this corollary discharge becomes an ingredient of the image of action that preceded the action, which starts to become habitual. The acquisition of bodily skills occurs in a similar way, of first learning the corollary discharge, and then having it become included as an ingredient of the action's image.

CHAPTER FIVE

Corollary Discharge in Everyday Life

W

E como ~oNSIDER any intentional action done b! ~ur~elves and reahze that the action comes with the ant1opat10n of the appropriate sensory outcome. Consider, for example, the use of a ladder. Having climbed up a few steps, we decide to step down, and since we do not easily see where to step, we rely rather on sensing with the foot where the next lower rung is situated. After taking two or three steps this way, we know where to expect the next rung, and we can continue with more confidence. lhe corollary discharge has been learned. Now, if by chance one rung has been broken or misplaced, we experience a surprising jolt. lhe expectation of the next rung was already part of the pattern, and something unexpected has happened. If we take as a further example the actiorl of reaching for a nearby object, then it is advisable to distinguish two aspects of the way the self is monitoring the action. lhe self follows the ongoing movement, compares the state of the reaching hand with the intended goal, and eventually decides to correct a possible deviation; on the other hand, the self acknowledges and confirms the sensory feedback that comes while touching or lifting the object, since this feedback has been anticipated by corollary discharges. Alternatively, if the object, known to the self from before, happens to stick to the underlying surface, for example, or happens to be

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very hot, then there is a surprise - the senses provide information that differs from what was expected. We may look at an object nearby and will probably remember something about it. When we look again, we might already know what to expect to see. lhe short-term memory, in other words, becomes part of the expected sensory feedback for our actions. When talking to someone, we listen to our own voices and monitor our own speech. It will never occur to us to wonder who is speaking because the corollary discharge presets our auditory cortex for receiving the auditory feedback; it is as if the auditory cortex is stating, "I am speaking and that is what I am hearing:' If it happens that my voice gets hoarse for an instant, I know what to do: I either cough for a second before I go on, or I repeat the word or the sentence. lhe corollary discharge enables me to monitor and control my action. lhe classical issue of perceiving the invariance of the environment when moving our eyes has been mentioned before (in chapter 2). When we handle an object, turn it around, or change its distance from our eyes, it remains the same object. lhe visual sense and the sense of touch are here participating with their corresponding corollary discharges. If we bend or cut the object, then the expected outcome enables us to monitor the changes, and to adjust, say, the amount or the direction of the applied force. If the object is a musical instrument and we are playing it, the auditory sense has its appropriate corollary discharges very clearly involved as well, as we expect to hear sounds that are part of the musical image, whether remembered or represented in musical notation. We monitor the outcome, taking into account quite a number of aspects: pitch, force, rhythm, quality of tone, etc. Situations like these, where we do intentional actions, monitoring them and checking whether the sensory outcome is as expected or not, happen during most of our waking life. A superficial introspection might confirm this.

CHAPTER SIX

The Self's Boundaries

W

ouT for some object in order to touch it, the corollary discharge presets our senses about the way it will feel in our fingers. Moreover, when touching some place on our own body, an additional corollary discharge presets our senses about the feel of that place on the body that is being touched. All this involves a learning process, and, ultimately, the expected sensory feedback will be there habitually. Touching our own body creates for us the image of self, which is different from the rest of the world. We know consciously that "this is me and that is not-me:' The boundary between the self and the outside world is clearly set. A little child, while touching places on his or her own body, learns that kind of distinction very early. The child's thinking, translated, as it were, into some rational language, could go this way: "That is a toy, I can play with it, and I can throw it away, but this is me; mommy is here and there, but this is me at the center of all interest:' Sometimes, when there is a disturbance in the feedback that comes from the site on the body that is being touched, the boundary between the self and the nonself is disordered. For example, during a dental treatment when local anesthesia is used, and the tongue and cheek are affected by the anesthetic, one might feel HEN REACHING

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one's own tongue as a foreign thing inside the mouth, and perhaps even try to chew it, until one realizes that this is actually the tongue, a part of the self. A person with a paralyzed arm that is not sensitive to touch might consider the arm as a useless appendage, and not a genuine part of the body. On this issue, an acquaintance of mine remarked jocularly that if God is omnipresent, or without boundaries, then He cannot have an image of Himself, or be self-conscious, for that matter. A person's self-image is not only static Oike a photo, or like one single frame of a movie film), but dynamic as well, consisting of actions and procedures that continue in time. Actions have their limits set by several categories of constraints. One kind, for example, involves the physical limits of the joints. When we try to overstretch the elbow joint, we know what to expect; earlier experiences will make us apprehensive, even when we are only approaching that point. The nearby environment provides another kind of constraint, for example, when we are doing a fast movement in the middle of a room, compared to doing a similar fast movement near a wall or some other nearby obstacle. The sensory outcome of such an action is anticipated. This is again a learning process, and the appropriate corollary discharges establish the action's limits accordingly. The habits we acquire during our lifetimes, with the corollary discharges already settled, create in themselves limitations for acting nonhabitually. The nonhabitual action, devoid of a clear expectation of the sensory outcome, brings the person to pay special attention to that outcome. In due time, perhaps, a similar action will come equipped with the appropriate corollary discharge, and the action might, in other words, be rather habitual. A person usually has a good reason for trying a nonhabitual action. Sometimes it might be due to necessity, and sometimes just due to curiosity. Doing a nonhabitual action is a way to transgress a certain constraint, a limitation of the way of acting. Any of the everyday actions that one does in a habitual way could serve as

The Self's Boundaries

27

an example. We put on a jacket by inserting first, say, the right arm. Trying it the other way, starting with the insertion of the left arm, seems odd. We perform some actions while considering limitations of a social nature, as when we act according to custom or to traditional rituals. Sometimes the limitations are of an ethical nature, as when we act according to moral or legal requests, whether we are guided by inner convictions or by a desire to avoid reprobation or punishment. As an extreme example, think of a reckless driver who might behave lawfully when he sees or suspects that there is a police officer patrolling nearby. The last paragraph presupposes "corollary discharges" that are not purely sensory in nature, but that are presetting anticipations all the same, and the feedback that comes with the action provides corroboration with the intention that the action had in the first place. Very often, we encounter limitations of intentional actions that are connected with changes in bodily structure, like those inflicted by injuries, accidents, operations, or degenerative changes that happen during various stages of life. Some structural limitations are congenital. Actions done under these constraints come with the anticipated limits or inabilities set by the corollary discharges, as one learns them through experience. A person who is aware of her or his restricted way of functioning might often give up actions that are not affected by the structural changes. The image of inability to do certain things often has the tendency to spread needlessly to other things. Let us see circumstances of this kind allowing a first approach to produce an improvement in that person's way of functioning, perhaps as the teacher might try to regain any movement elements that have been unnecessarily given up by the person.

CHAPTER SEVEN

Impairment and Rehabilitation

I

to be of some help in overcoming another person's impairment, then a good way to start is to distinguish structural limitations from functional ones. Changes in structure (skeleton, ligaments, etc.) or damage that has been incurred by some part of the nervous system are the domain of the medical profession, and I am not intending at all to look into possible ways to relate to structural changes of any kind, at least not in the framework of the Feldenkrais Method. If there is no explicitly declared contraindication from the structural point of view, then the way might be clear to look into clarifying the way of functioning. Functional impairment means that some, or perhaps all, ingredients of an intentional action might be inhibited or might even not exist. The ingredients (or components) of voluntary actions have been mentioned in chapter 3. I intend to present a few examples that show ways of enhancing and clarifying some of those components, so that the likelihood of utilizing the action in question might increase. The notion of corollary discharge might again show its practical importance. As already mentioned, anticipating a sense of inability, inadequacy, or pain when considering a certain action elicits the instinctive tendency to avoid that action. Very often this is more than just abstaining from doing; it can take the form of an active F wE INTEND

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defense pattern, an activation of the antagonist muscles simultaneously with the respective agonists, resulting in stiffness and restricted freedom to move. This kind of "freezing" may become habitual. One of the possible ways to change this, as proposed by the Feldenkrais approach, is to consider, for example, other patterns of action that involve or use the same antagonists, but this tillle as agonists or synergists. Those alternative ways of acting have different expectations and come with different corollary discharges, and thus they circumvent the former expectations and allow some easier way of acting. By utilizing alternative ways of acting, the person might achieve better control over the muscles involved, and the initially restricted action might become feasible. We have thus a change in the level of control from a lower level towards the more aware cortical level. As an example, let us take low back pain. When one does not have to worry about structural problems, one can look at the state of the trunk's flexors (the belly muscles) that work as antagonists to the tense and suffering back muscles. Both muscle groups might simultaneously be in a state of increased tension. Moreover, any additional tension in the belly muscles calls for several degrees more additional tension in the back muscles in order to maintain balance and not to flex the trunk, an action that, probably, has not been intended at all. To clarify this last Point, think of the upper part of the trunk as a lever pivoted on some lumbar vertebra, and of the distances from the pivot of both lines of the flexors and the extensors as "arms" of the lever. The "arm" of the flexors is several times bigger than the "arm" of the extensors, which is an other way of saying that the back muscles are very near to the vertebrae, compared to the belly muscles, and they suffer, hence, from an increased (and probably painful) tension. Alternative ways of using the flexors could be side flexion of the trunk, rotation, or both combined, all attempted in a slow and gradual manner and in a position that provides a sense of security and comfort. When the practitioner feels that those movements are getting easier (meaning that they have been accepted), then

Impairment and Rehabilitation

31

he or she could gradually try some flexing or extending of the trunk, both of which have been difficult and painful before. A similar idea can be illustrated as follows. Many muscles are involved in more than one pattern of action and thus have different antagonists connected to them. If one such pattern, perhaps the habitual one, is inhibited by negative expectations or by impaired cortical control and presents stiffness, then it is worth trying the other pattern, perhaps a nonhabitual one, in order to improve the control over the muscle in question. In cases of hemiplegia following a cerebrovascular accident (CVA), such stiffness might occur, for example, in one of the arms; the biceps and triceps muscles work simultaneously and allow neither flexion nor extension of the elbow joint. On the other hand, the biceps functions also as a supinator (it rotates the forearm outwards), and has in this function a different antagonistic connection. If the rotation of the forearm seems acceptable, then doing it gently will elicit corollary discharges that are less inhibiting and, ultimately, the extension of the elbow will become possible. In other words, the level of control will go up, towards the cortex. The image of voluntary action might be incomplete in cases where the afferent nervous fibers are damaged. Those fibers are supposed to transmit the sensory feedback of the kinesthetic sense, needed for monitoring the action that is going to happen. To complete that image somehow, I have used the idea of substituting another sensory modality to enable the person to monitor the action, until the impaired kinesthetic sense becomes clearer and sharper. Here are two examples from my practice. A woman in her thirties had undergone surgery on her lumbar spine for removal of a tumor, and was left with a paralyzed left leg. She had to use a crutch in walking. Sitting with straight legs, she could move voluntarily neither her left ankle joint nor the toes of her left foot. When I tried to move those toes gently, she succeeded at rrioving them by herself, but only while looking at them. It turned out here that the respective sensory fibers had been damaged, but not the motor ones. I advised her, of course,

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COROLLARY DISCHARGE, THE fORGOTTEN LINK

to do those movements while looking, and to look away now and then, until the impaired kinesthetic sense could take over in monitoring and controlling the actions of her toes and ankle. A flutist 5 had suffered a severe injury to his right arm when a bullet pierced the arm, slightly above the elbow, disrupting the median nerve almost completely. His right thumb, forefinger, and middle finger were all impaired in their function in the severest way. At a certain stage of our work, after having already achieved some movement in those finge~:s, he took up the flute in order to try to play it. The thumb of the rigl).t hand supports the flute from underneath, and the other fingers close or open the "keys" from above. Our flutist could not yet reach those keys with the fingertips, as required; he could, however, reach them with the middle phalanges of those fingers. Moreover, the fingers' kinesthetic sense being not yet refined, our flutist felt that the control of the fingers' movements was not satisfactory. The visual feedback was not applicable here, because he couldn't look at those fingers while holding the flute in the playing position. For example, while the right forefinger had to be kept on the key for a while, it was slipping somewhat to the right and touching the nearby so-called "trill-key," producing an annoying, unwanted tone. The flutist reacted with a grimace of disgust. I said to him that he shouldn't be disturbed by those tones. They were, for the time being, the only source of information about how these fingers were behaving on the flute. He could take them as cues in knowing how to adjust and coordinate the movements of the fingers. And so in this case, the auditory sense provided an alternative channel of feedback for the motor functions of the fingers.

For a detailed description of this case, see Rywerant, Y. (2003). The Feldenkrais Method: Teaching by handling(chapter 12). North Bergen, NJ: Basic Health Publications. (Originally published 1983) 5

CHAPTER EIGHT

Conclusion: The Body-Mind Link Reconsidered

R

Of the psychophysical gap that was mentioned in the preface, I can sum up a few ideas. It is difficult to form an opinion or to assume a philosophical stance in the question of the gap between mind and body, be it reductionism or dualism, for example, given the antithetical discussions that are going on among neurophysiologists and philosophers. On the other hand, in any learning process, and in any monitoring of intentional actions, the physical part and the mental part (sensation and perception, doing and thinking) emerge together. Sometimes, even the question of which causes which has no meaning, and both parts appear to be just two aspects of the same occurrence, like two sides of the same coin. It seems that from the practical standpoint, at least, the phenomenological stance is appropriate. Firstly, one evades the ontological issue of whether all is based on one single substance or on more than one (mind and matter). Secondly, considering two aspects of the same phenomenon, the question of which causes which loses its relevance, and even its meaning. One can obtain a helpful intuitive sense of what is meant by these notions through the consideration of a device proposed by David Bohm. 6 Suppose ETURNING TO THE ISSUE

Bohm, D. (1983). Wholeness and the implicate order (p. 187). London, Boston, Melbourne, Henley: ARK.

6

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we have a rectangular aquarium with fish swimming around; further, we have two TV cameras positioned at a right angle so that one takes in the aquarium's front and the other its side. UJ.en we have two TV sets in another room that make visible those images. We will see a certain relationship between the images appearing on the two screens. For example, we might see an image of a fish on one screen and another image on the other screen. At any given moment, the two images will generally be different. Nevertheless, the differences will be related in the sense that any movement done by one will correspond to the movement done by the other. Moreover, the content of one screen is "passing over" into the other, and vice versa. llius, at all times, the image content of one screen will correlate with and reflect that of the other. Of course, the two images refer to a single actuality, and this explains their correlation, without the assumption that they causally affect each other. llie monitoring of one's own intentional actions is an activity amenable to everyone's introspection. llie corollary discharges that come with intentional actions and the changes that occur with those corollary discharges during the adaptation and habituation of the respective actions present a detailed and perhaps easily analyzable connection between sensation and perception. Sensing, perceiving, and their interactions are very frequently occurring activities of the conscious mind. Consciousness involves, after all, several processes: committing to memory, recalling from memory, perception of sensory input, attention, ti:tning of perceived or performed events, monitoring of intentional actions, acts of understanding, planning future actions, making maps, and many more. Some of the modern brain-imaging methods might be required to elucidate and localize those changes, as those brain-imaging methods have already clarified other brain activities. Investigations of that kind might be a good way of bridging over the "body-mind gap:' llie various ingredients of the images of intentional actions (their adaptation, clarification, and completion), as they are so notably applied in any learning process, and

Conclusion: The Body-Mind Link Reconsidered

35

the pertinent role that corollary discharges have in that process, present a fruitful field of investigation. 1he Feldenkrais Method, as I tried to show, makes ample use of the notion of image of action and of the relevant sensory anticipations, by relating to the corollary discharges in question. 1he method and its practical application, already practiced by a great number of teachers (practitioners of the method) as it were, just invites some further elucidation, in scientific terms, of the body-mind issue, as well as, for example, the issue of free will and the issue of interpersonal communication. We have a quite similar situation in quantum theory, where subatomic objects (electrons, for example) behave more like waves or more like particles, as their behavior is actualized in different experimental arrangements. One considers this waveparticle duality valid, despite the fact that there is some difficulty in grasping this intuitively. We could see the body-mind "gap" in a similar way. 1he event in question "behaves" body-like or mindlike, depending on the specific arrangement or observation we might be interested to follow.

References

Bohm, D. (1983). Wholeness and the implicate order. London, Boston, Melbourne, Henley: ARK Carpenter, R. H. S. (1990). Neurophysiology. London, Melbourne, Aukland: Edward Arnold. Crick, F., & Koch, C. (1992). The problem of consciousness. Scientific American, 267, 152-159. Freeman, W.]. (2000). How brains make up their minds. London: Phoenix. Teuber, H. L. (1966). Alterations of perception after brain injury. In]. Eccles (Ed.), Brain and conscious experience (pp. 271-276). Berlin, Heidelberg, New York: Springer. Rywerant, Y. (2003). The Feldenkrais Method: Teaching by handling (chapter 12). North Bergen, NJ: Basic Health Publications. (Originally published 1983)

37

In Corollary Discharge, The Forgotten Link, Rywerant brings his 111,1\tny of the field of mind-body education to bear in understandin g ,, vn y present but little-understood aspect of neuromuscular ttllll'tioll . It brings this sometimes subliminal aspect of our worlds to our co11sn< Hi s awareness, both for the appreciation of the function and so t h.1t \\'< ' may begin to make more conscious use of it. The expansion o( o111 awareness of corollary discharge has huge potential f(>r enh .111CI11 g motor functioning. Yochanan Rywerant (b. 1922) was one of the main assistants of I >1 M"'"' Feldenkrais. In 1952,Yochanan, then a physics professor in a secondary ,1·lu u •I •.J• >II H.' .ll t' 11 1 them once a week for fifteen years. Yochanan was one of the p.trtlllJ>.IIII S 111 II >< · first Professional Training given by Feldenkrais, starting in l 1)(, 1) . I 'm fllt< ' 1111 ,. then, he has worked extensively as trainer in Professional Tr;llnings 111 tl11' l J\A , Canada, Europe, and Israel. His book, The FeldCIIkrais Alctlwd, 'Ji•ctrltiiiX b)' //,1/tclliu.t:. appeared in English in 1983, and has been translated into (;nm.lll , SJ> .IIII ' h , lt.d1.11 1, and Hebrew.