The relation of muscular tension to bilateral transfer

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THE RELATION Of MBSCtRAR TENSION /

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M bttittcd t© the faculty ©f tilt Q^adnat© School in p a rtia l fulfillm ent of $ht rtquiramenta for th* &ag?Mt Doctor of -Philosophy, in the S tpart^ent'of M ythology, Indiana University, October, 1941

ProQuest Number: 10295110

AH rights reserved INFORMATION TO ALL USERS The quality o f this reproduction is d e p e n d e n t upon th e quality o f th e co p y submitted. In the unlikely e v en t that th e author did not send a co m p lete manuscript and there are missing p a g es, th ese will b e noted. Also, if material had to b e rem oved, a note will indicate the deletion.

uest ProQuest 10295110 Published by ProQuest LLC (2016). Copyright o f the Dissertation is held by th e Author. Ail rights reserved. This work is protected against unauthorized copying under Title 17, United States C o d e Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 - 1346

Accepted by tfae fa c u lty of th e Graduate School o f Indiana U niversity as f u l f i l l i n g th# th e s is requirem ents fo r th e degree o f Doetor o f l*hlleM¥ihy.

Doctoral Goraialfcteej

__ ______ _ Chairman

(J G u d H i.

11

AQmoM*mmmT My tban&e are due to the members of my committee fo r th e ir c a re fu l guidance and sugges­ tions*

E specially am 1 indebted to hr* K. 0* Davis

fo r d ire c tio n and the use o f equipment.

m a w or oo-hybnts

$msl*

Ctiapter x*

amA m htua o r b il a te r a l Tfuuw ra*..............................

i

A* Introduction* *.................. ................. .. * * X B* The Place of B ila te ra l T ra n s fe r.. . . . . . . . . . . 3 0. H istory o f the Study o f B ila te r a l Transfer* 7 T ransfer of discrim inatory or Perceptual A bility* *.......... ....................... ............... *** 8 T ransfer o f S k ills Largely Perceptual***. 10 T ransfer o f Conditioned Responses. IT T ransfer of Tasks Involving New Response P a tte r n s ...... .............. . . . . . . . . . . . . . . . . . . 19 T ransfer of Fatigue— "Negative Trans­ fer? *. ........................ ................ ................. * 20 Location andD irection o f T ra n s fe r.. . . . . . 24 C ontributions to Methodology in Transfer E x p e r i m e n t s * ............. 26 The Neurology o f B ila te ra l T ra n s fe r.. . . . * 30 Theories of T ra n sfe r. ............. 36 B* Development of Hypothesis? The Problem.. . • 47 II*

m

EXPERIMENT............

M

. ........................

A.

The A pparatus. ........ The Learning Task. . . . . . . . ............................. The Measurement o f T ensions............... .... *. * B* The Procedure. ............................ S ubject1s Task.. •. ......... Measurement of A c tiv ity . ........... Experimental Cont r ol s. . . . . . . . . . . . . . . . . . . . C* The Experimental Dat a. . . . . . . . . . . . . . . . . . . . . . ......... S ubjects' Learning Records* S u b jects' Tension Records................ B. Discussion of R esu lts............ . E. Summary and Conclusions.

REFERENCES. .........

...............

54 54 58 60 60 64 67 71 71 79 99

103 105

Iv

LIST OF TABLES TaKU

£aea

1, LEVEL OF TENSION FOB LEFT HAMS SHOWING THE EF­ FECT OF THE TENSION REDUCINGCONTROL. .......................

TO

2. FLAK OF THE EXPERIMENT...................................................

71

5. INDIVIDUAL LEARNING SCORES,GROUP A . .................

73

4. LEARNING SCORES, QROUF B .. .............................

74

■6. LSAHMIMG SCORES, GROUP 0 . , , .................................

70

6. DERIVATION OF THE PERCENT OFTRANSFER.....................

7B

7 . LEVEL OF TENSION IN HEAR MICROVOLTS, GROUP A RIGHT HAND. . .......................................

80

8 . LEVEL OF TENSION IN MEAN MICROVOLTS, GROUP A LEFT HAND...........................

81

9. LEVEL OF TENSION IN MEAN MICROVOLTS, GROUP B ............................... RIGHT HAND.. . .

82

10. LEVEL OF TENSION IN MEAN MICROVOLTS, GROUP 3 LEFT HA8D...............

83

11. LEVEL OF TENSION IN MEAN MICROVOLTS, GROUP C BIGHT HAND...............

84

12. LEVEL OF TENSION IN MEAN MICROVOLTS, GROUP G LEFT HAND.............. ; ..................

86

13. LEVEL OF TENSION IN PERCENT OF REST MICROVOLTS, GROUP A BIGHT HAND.. , .........................

86

14. LEVEL OF TENSION IN PERCENT OF REST MICROVOLTS, GROUP A LEFT HAND.................

07

16. LEVEL OF TENSION IN PERCENT OF REST MICROVOLTS, GROUP B RIGHT HAND............................................................

88

16. LEVEL OF TENSION IN PERCENT OF REST MICROVOLTS, GROUP B LEFT HAND..............................................................

69

17. LEVEL OF TENSION IN PERCENT OF BEST MICROVOLTS, GROUP C RIGHT HAND............................................................

90

18. LEVEL OF TENSION IN PERCENT OF REST MICROVOLTS, GROUP C LEFT HAND.............................................................

91

19. COMPARISON OF TRANSFER AND IMPLICIT ACTIVITY..... 100 20. SIGNIFICANCE OF THE DIFFERENCES BETWEEN GROUPS.. . 100 V

LIST OF FIGURES Pleura

Paera

3L

DIAGRAM OF LEARNING DEVICE.................................... ....

5?

3.

SAMPLES OF LEARNING RECORD.

8?

8*

DIAGRAM

4*

TENSION IN SEAN MICROVOLTS FORNORMAL ANDIN­ HIBITED GROUPS.

S*

LEARNING CURVES............. ........................... ............... ..

77

6.

MEANLEVEL OF TENSION, GROUP A...................

93

7.

MEANLEVEL OF TENSION, GROUP B

94

8.

SEAN LEVEL OF TENSION, GROUP 0............................

...............................

o r APPARATUS ARRANGEMENT At©WIRINGPLAH. @1

Vl

..............

70

95

1

CHAPTER X AH AHALXSX8 OP BltATSHAL TRAHSfSR A* Intro d u ctio n Although p erip h e ra l muscular phenomena have long been o f I n te r e s t to psychologists, i t I s only re c e n tly th a t much o f th e re la tio n s h ip s o f im p lic it a c tiv ity to o th e r processes have boon elevated from th e le v s! o f lo g ic a l oons tr a c t to th a t o f observed data*

This I s , o f course, In

la rg e p a r t duo to th e v a st Improvement in apparatus and techniques.

iueh musoular a c tiv ity as has been studied i s

u su ally re la te d to some fo ra o f motor theory o r , more re** c e n tly , to p erip h e ra l theory,

follow ing th e suggestion o f

Davis ( i t ) , i t seems wise to adopt th e l a t t e r terminology,, thus r e la tin g psychological f a c ts measured o b je c tiv e ly to p erip h e ra l muscle changes measured o b je c tiv e ly .

Xn so do*

la g we elim in ate th e n ecessity o f dealing w ith a trouble* seme concept o f consciousness p resen t In th e m ajority o f motor theory c o n stru c ts.

Xt i s not to be supposed th a t in

accepting t h i s viewpoint we n ecessarily ru le out the possi* b U ity o f any so*ealled "cen tral" concomitants o f the psy* ehologleal process under co nsideration.

Hadley (42) has re*

ee n tly been unable to fin d any c o n siste n t re la tio n s h ip be* tween c e n tra l a c tiv ity (EStf's) and p erip h eral a c tiv ity (myo* grams) during a s ta te of r e s t,

fu tu re In v e stig a to rs may be

2 studying two u n ralated ays te a s , according Co h i a view.

Is

n ig h t p o in t o u t, however, th a t under the p resen t widely ac­ cepted view o f neu ral function impulses w ithin the o e n tre l nervous .ayetep su e t r e s u lt in p e rip h e ra l a c tiv ity of seme sort*

A peripheral, theory .does not exclude th e p o s s ib ility

of th e Importance o f b rain a c tiv ity any a c re than i t excludes p e rip h e ra l a c tiv ity o th e r than th a t under in v e stig a tio n . h o st of the work which has been re la te d to p e rip h e ra l theory has been w ith problems termed g en erally "mental work". I t i s o f course d e sira b le in th e development o f any theory to in v e s tig a te a s wide a range o f a p p lic a b ility as p o ssib le , eensequeatly, the few cases o f in v e stig a tio n s which r e la te probte®s not u su ally c la s s ifie d as "mental" to p erip h e ra l theory a re noteworthy.

Davis (21) has re c e n tly in v e stig ate d

the ru le o f p erip h e ra l fa c to rs in reactio n time responses. Payne and Davis (S3) and Freeman and Sharp (3?) have con­ trib u te d inform ation concerning th e fa c to r o f tension in the judgment o f l i f t e d w eights.

Both o f these stu d ie s are ex­

c e lle n t examples o f o b jectiv e evidence regarding problems where answers have long been h y p o th etical and vague.

I t is

the purpose of th e p resen t in v e stig a tio n to carry the ques­ tio n o f p erip h e ra l a c tiv ity in to the s t i l l more complex area o f le a rn in g , r e la tin g i t p a rtic u la rly to th e phenomena o f b i l a t e r a l tra n s fe r. beam ing has tr a d itio n a lly been supposed to have i t s locus w ithin th e nervous system, and more e sp e c ia lly upon

3

th e eo rte * .

Thorndike’ * neural b o ats concept i s probably

th e boat known o f a l l o f these various oonstvuots regarding le a rn in g .

In s p ite o f the f e a t th a t a s lg n ifio a n t amount

o f m M a l work p o in ts to the extreme in d e fin ite n e ss o f th e loeua o f le a rn in g , a e u ra l views a re ten acio u sly held by wore modem th e o ris ts ,

wheeler*a neurologioal in te rp re ta tio n o f

b il a t e r a l tra n s fe r (39) i s a good example.

To the p re se n t

w rite r I t seem* reasonable to aseep t whatever o b je ctiv e e v idanoe is 'a v a ila b le a s being th e sto ry o f the response aeehaaisB s in le a rn in g , u n ti l such a tin e as n e u tra l a c tiv ity nay be-demonstrated*

th e le arn in g problem of b i l a t e r a l

tr a n s fe r sense to be s u ffic ie n tly adaptable to s im p lifie s tlo n fo r a study o f th e ro le o f the- response mechanisms. I t i e seareely necessary to p o in t out th e value of an i n i t i a l a tta c k upon suoh a complex problem as- learn in g in a s simple a form as possible* •* The Plane of B ila te r a l T ran sfer In the experim ental l i t e r a t u r e , the to p is o f b i l a t e r a l tra n s fe r i s almost hopelessly interm ingled w ith problems o f tra n s fe r o f tra in in g .

Bevies* of the l i t e r a t u r e , such as

those of B re m e n (9 , 10) devote most a tte n tio n to the tra n s ­ f e r from one task to another ta sk .

In te rp re ta tio n s o f sh a t

l i t t l e b il a te r a l tr a n s f e r inform ation i s included are in v a ri­ ably made in re la tio n to edueational theory.

Textbook

w rite rs o ften devote a few paragraphs to b il a te r a l tr a n s f e r

4

in th e middle e f a ah ap tar m th e tr a n s fe r o f tra in in g , and make l i t t l e o r no e f f o r t to d if f e r e n tia te th e two to p lo s Cowrie, IU A ., Id , e .g .) .

Some workers, fo r example Eaton

(£?), have even suggested th e n e t o f re e o lte o f b ll& tero l tr a n s f e r experlm sntation to In te rp re t problems o f th e tr a n s ­ f e r e f tra in in g .

Hie study l a designed to throw some l i g h t

e s th e ^troublesome educational toplo o f tro n a fe r o f school su b jects* .

Vlth a few exceptions, even th e m reeearohere

whose la te r e a t has been In th e b il a te r a l phenomenon have tre a te d t h e i r toplo an I f i t were, a branch o r sub-topic un­ d er th e problem e f tr a n s f e r o f tra in in g . C ertain very s trik in g d iffe re n e e e between th e twe la d ie a te th a t th le arrangement le probably untenable.

K.is~

to r ie a lly they are re la te d because o f th e foot th a t cam ea th e o rie s have been advanced to explain them (see page 36f). L ogically l i t t l e nore than a common none unltoB them*

traaa*

f a r e f tra ln la g may be defined as the- n et o f p rao tlain g one ta sk end noting I t s consequent e f f e c t ( f a c u l t a t i v e o r ia» h ib ltlv e ) upon a d if f e r e n t ta sk .

Experim entally th e proced­

u re l e oa followet

ot

P w m iim

Exoerlmental £

ja a s a a . 2 m a

1 tm%

X Test f m k b

A

z Pvrntim T&gk B

2 H ist

3 TA.it fm k a

3 Test Taslt A

8 Zhs tr a n s f e r e ff e c t l a the caesura re s u ltin g fre e th e sub­ tr a c tio n o f #8 minus #1 (co n tro l) f r m #S a l m s #1 ( e x p e rta e a ta l) . On th e o th e r band, b i l a t e r a l tr a n s f e r la th e a c t o f p ra c tis in g one to o l with a given body p e rt ana noting i t o eeaasqpent e ffe c t open the sa c s t e s t performed by a d i f f e r e a t body p e r t, (usually) sy m etsd e al and opposite to the p ra c tic in g member.

Sfee procedure then I s Id e n tic a l to She

above c se sp t th a t tho too ap p ro p riate body n eu ters are sub* e tltu te d fo r tb s too ta s k s { the tra n s f e r e f fe c t I s tre a te d s im ila rly to tho above.

A s im ila r procedure does 'not aseee-

'1 .

e a r lly r e la te th e too to p ic s, sin ce many psychological ex» p e rle e n ts fo lle o t h i s scheme. Furtherm ore, one fin d s both fa o ilit& tiv e and tn h lM tiv e tr a n s f e r e f f e c ts in the l i t e r a t u r e o f tra n s fe r o f tra in in g ,

negative e f fe c ts are In te rp re te d in terms o f th e

dynamics o f in te rfe re n c e , and are elo eely re la te d to r e tr o ­ a c tiv e in h ib itio n ,

th e tr a n s f e r e f fe c t in b i l a t e r a l tra n s ­

f e r i s almost u n iv e rsa lly f a c u l t a t i v e , except those cases o f th e tr a n s f e r o f fa tig u e which are tre a te d as a s p e c ific kind e f p o s itiv e tr a n s f e r (see page 23). i * ® i t h e few sjinor ex cep tio n s,“ .Gooi s ta te s (1 ?), which are "probably due to chance e rr o r s , a l l experiments in th e f ie ld o f srees-sd u set i c s flad -seae. p o s itiv e tr a n s f e r ." negative e ffe c ts in eases e f tra n s fe r o f tra in in g are c e rta in ly not caused by fa tig u e , d u e s th is i s c a re fu lly c o n tro lle d .

From th e se

0 esisparisons I t would csss th a t t h e ir re la tio n s h ip I s wore s u p e rfic ia l than r e a l, and about th e most th a t ea» be said lMirafpn t t a-tpt

^P»t3«5pL._r

sw

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pwwwwiioi'f

Thsre i s no lo s s confusion l a the f ie ld as reg ard s th e terminology employed.

th e term s * b ila te ra l tr a n s f e r 8

and "croso-education* hate been about equally used, and in terahangeably. / n e i t h e r i s a very accurate term , sin e s many stu d ie s show tr a n s fe r to body p a rts o th e r than a symmetri­ e s ! muscle group (see page 24)| one mentions tra n s fe r to head movements—avppeeedly Involving musculature on both sid e s o f th e median lin e (&3){ and s t i l l another re p o rts tra n s fe r fro® a muscle group to i t s antagonist group (71, 72)«

to s a tis f y a l l o f these oonditions, Coot (17) has sug­

gested th a t the term *intra-m usoular" o r "in tra -o rg a n io 8 tra n s fe r i s more acceptable.

l e t , out o f dsferenoe to t r a ­

d itio n , he eontinues to use the term "eroas-eduoation" * •Croea-induotion* has been used by T a llin (37),

Sine® ."b i­

l a t e r a l tr a n sfer" i s the term most frequently found, i t w ill be used throughout the present study,

follow ing the usual

lab o rato ry term inology, learn in g t r i a l s s h a ll be c a lle d the p ra c tic e s c r ie s , t e s t t r i a l s before p ra c tic e s h a ll be c a lle d th e p re -p ra c tic e s e r ie s , and t e s t t r i a l s a f te r p ra c tic e s h a ll be c a lle d th e p o s t-p ra c tic e s e r ie s .

The muscle group p er­

forming the o rig in a l learn in g i s th e p ra c tic in g member and th a t group to shiah learning i s induced i s th e tra n s fe rre d member.

This terminology i s not th a t used by a l l of th e

7 1m w M m reports In the field* but I t i s the most accepted# Again, theories e f transfer have widely d ifferin g lattsrprsiatlefis#

Sine# th is i s not wholly a matter o f t# r-

mlmology the problem a l i i he d ealt with in a la te r section (j* c *

36 >*

8* History o f the Study o f B ila tera l Transfer There are no s a tis fa c to ry re v ise a r t i c l e s covering th i s topis* although some surveys o f tra n s f e r o f tra in in g w ill s i t e a few referen ces to b il a t e r a l tra n s f e r , m am » tloskod above#

th e b e st approach to a survey le probably

found in th e a r t i s l e by fla g (73) and a s e rie s o f a r t i c l e s by dock (13*17) # The b e st secondary sources a re loodMirth (73) * B ills (4) and Hunter (48)* although many general te a ts mention one o r more

mpmkmmt# (3, 19, 26f 89 , 70)#

Several o f the e a rly observations on th e problem e re reviewed in a number of papers (see e sp e c ia lly Bray, 7)# Feetoer (89) i s given c re d it fo r th e f i r s t communication on the matter#

This paper reports seme non- m p er iment a l ob­

serv atio n s made by Feehaer and by Weber# / F i r s t major work r e la tiv e to the tr a n s fe r of t h i l l s i s probably th a t o f scrip tu re# Smith* and Brown In 1894 (80), although in 1892 Bryan (11) had noted the tra n s f e r o f fa tig u e in connection w ith a motor task#

S cripture studied the tra n s fe r of im*

prevalent, in stead in ess and stre n g th , and t h i s lead was fo l­ lowed by W* f# Bavis In 1898 (83) and 1900 (84)#

Some o f

a ttWW e a rly stu d ie s lacked so muoh la experim ental cen tso l* th a t Ifceir re o S lts are l i t t l e

bom

than h is to r ic a lly Into**

e s tln g . A survey o f av a ila b le inform ation might be continued In chronological sequence, but more in s ig h t w ill probably be obtained by attem pting an o rg an isatio n o f th e studies* G lear-eut d iv isio n s e f th e to p lo c e rta in ly do not exist* Xet one «sy make c e rta in groupings in order b e tte r c r i t i c a l l y to exmmlfte t h e i r alg n iflaan o e.

Many d iffe re n t kinds of a b i l i ­

t i e s have been used to show tr a n s f e r , and th e se w ill be ex­ amined f ir s t* to a afiaE M f& m xttikM tevi m iM U S i* voik* oann’ s ra th e r extensive study on two p o in t cutaneous d is ­ crim ination (63) appeared w ith Feehner'e paper in 1858. VeUsMW had obtained eonsldsrable improvement in the subJ e s t 1'e a b i lit y to oaks sush a d ie o ria in a tio n and a lso found th a t almost as much improvement was tra n sfe rre d to th e op­ p o s ite sid e , but only to areas symmetrical to the tra in e d ares*

P re s s la r (88) v e rifie d th e finding and added th a t

th e re was a q u a lita tiv e d ifferen c e in sensations from the tra in e d o r tra n s fe rre d areas as compared w ith o th er adja­ cent areas*

Using re v e rsib le p ersp ectiv e illu s io n s , W allin

(6?) demonstrated tr a n s f e r from one eye to the o th e r, and from the fovea to th e periphery o f a sin g le eye.

in te rp re ­

ta tio n s o f both P re s sla r and Wallin involve the a c tiv ity of

9 c e n tra l fa c to rs la rg e ly .

However, the l a t t e r w rite r did

acknowledge m e f a c t th a t simultaneous fix a tio n s e f th e tin* tra in e d eye may have been Im portant,

Fran* (33), who wae

*]>N in te re s te d l a the tra n s fe r e f v is u a l perceptual a b i l i t y , taught h ie su b jects to d iscrim in ate fig u res in p erip h e ra l vision# then measured th e tr a n s f e r to th e periphery o f th e o th e r eye*

K ffeots were obtained to both th e sane and op*

p o s its r e t i n a l areas In th e tra n s fe rre d aye.

T ransfer was

n early 100$>j I t "equalled or approaehed the tra in e d eye*. Frans thought i t was not re a l tr a n s fe r sin es id e n tic a l a o rt l e a l a re a s were involved,

Lashley (32) also re p o rts 100£

tr a n s f e r fro* eye to eye in the v a t. ttuUn and Kate (43) used a tttueh wore complex type o f d is e rin itia tio n , th a t o f reading B ra ille .

E ffe c ts were stud­

ied tram tra in e d to tra n sfe rre d hand and from v isu a l le a rn ­ ing to a tra n s fe rre d hand.

In terms of f a c i l i t y in die*

crim ination e f m e ch arac ters o f th e alphabet, there i s a tra n s fe r o f almost 10C$>, and a much g re a te r amount of tra n s ­ f e r from hand to hand than from eye to hand.

The authors

fe e l th a t th i s in d ic a te s "th at th e tra n s fe r i s not c a rrie d wholly in terms of v is u a l imagery". tra n s fe r o f k in e sth e tic p a tte rn s .

Levin (33) studied the T ransfer e ffe c ts were

la rg e , fo r * lf p ra c tic e was given to one hand, reproductions could he equally w ell effected by the o th er hand”.

P a tte rn s

which wore f i r s t observed (S watches Z perform) were tra n s ­ fe rre d more rap id ly .

This f a c i lit a tin g influence probably

10 docs n e t operate in rev erse, since Becker (2) re p o rts th a t su b je c ts who tra n s fe rre d eutaneously learned p a tte rn s rood* U jrt gave no in tro sp e c tio n s in terra b of v isu a l images*

The

n e st s trik in g f a s t fro a a l l e f theee stu d ie s i s th a t tra n s ­ f e r i s almost complete when th e s e t I s a purely Alaorim lasW'#Trj^r

f a a t t f f g sZ S k ills hargely P ercep tu al.

At th ia point th e

question may troll he asked as to shot makes a given le a rn ­ ing t&Sk la rg e ly perceptual or la rg e ly motor. d ls tin e tio n he made?

Can a v a lid

The problem may oome down to a m atter

of th e In v estig ato r* s opinion* o r more properly* th a t o f h is subjects* regarding any sp e c ific ta sk .

I t does seem c e l l

w ithin th e realm o f reason, however, to say th a t in le a rn ­ ing some S k ills , su b jects need not gain in muscle f a c i l i t y , nimbieness nor force o f movement.

A nalysis nay show th a t

they simply a tta c h o ld response p a tte rn s to new stim u li. The learn in g task then c o n sists o f a progressive discovery o f these stim ulus re la tio n s h ip s . many conditioned responses.

Such is th e nature o f

Again the type o f blind s ty lu s

mass found in most la b o ra to rie s i s a case in p o in t.

Aware­

ness o f the conditions o f the immediate environment I s r e ­ duced to k in e sth e sia —a very poorly developed perceptual modality* to be su re.

Hemove the handicap and even the

poorest su b ject runs the f i r s t t r i a l sans e rro r! g ressiv a curve o f accuracy i s p o ssib le .

No pro­

True, under such

conditions a subject may (how something of a learning curve

{

11 by Improving speed, and th i s may be eeneeded to in d ic a te what p o rt le a e f th e t a d l a motor* aa oppoaed to d a much la rg e r p erceptual problem. On d o o th er hand, c e rta in t a d s may be Ju st ae h eav ily weighted in the d ire c tio n o f improvement in m eter coordinations.

Mere the stim u li are not p a rtic u la rly new*

su b ject has had experience w ith them (or s im ila r ones) in th e past*

Me must now concentrate upon developing and re*

fin in g responses*

Of course, th e perceptual fa c to r l a not

ab sen t, tout i t may toe minimised,

one may draw a s trik in g

analogy from the fa m ilia r stim ulus and m eter s e ts found in reactio n time work| a tte n tio n may toe upon c ith e r th e stim uIn s o r th e response.

A laboratory example e f a ta sk large*

ly motor would toe th e dynamometer, stead in ess, o r p re c isio n e f movement.

Such a d is tin c tio n as the above i s not meant

fo r an argum entative debate tout i s o ffered in referenoe to th e o rie s of tr a n s fe r which w ill toe discussed l a t e r .

M ill*

sen and Van h ip er (S6) have pointed out th a t most researches i s b i l a t e r a l tr a n s f e r have employed perceptual ta sk s, and t h i s i s an im portant fa c to r in th e trend of th e o re tic a l exions e By f a r the most frequently used learn in g device has teen th e m irror trac ed s ta r (o r other) p a tte rn .

Starch (63)

as e a rly a s 1910 described i t s use in lab o rato ry c la sse s end reported th e amount of tr a n s f e r fo r a few subjects*

Ef­

f e c ts around 83$> improvement were shown, tout co n tro ls were

18 n a t r ig i d ,

H ill (44) also mentions obtaining tr a n s fe r w ith

sMh a devise la th e classroom.

Swart (88) da signed an ex*

p e ria e n t to check th e tr a n s f e r fig u re s o f s ta rc h , using more exeet c o n tro ls. ■ t i l l h ig h .

T ransfer e f fe c ts were somewhat lower, h a t

SiipoXa idg) aaed th e m irror tra c in g equipment

i a a c r i t i c a l examination o f th e perception fa e to r.

Group

A etHtervet (v isu a l perception) ten t r i a l s made by another su b je c t, while Group 8 p ra c tic e d te n t r i a l s w ith one hand, hath groups were then te s te d fo r th e tr a n s fe r e ffe c t to th e o th e r hand,

th e tr a n s f e r of Group 8 was only s lig h tly su­

p e rio r to th a t of Group A.

th e psychologically im portant

d ifferen c e between the groups i s the fa c t th a t Group 8 had a l l o f th e p ro stte * of Group A p lu s k in e s th e tic clues and whatever amount o f a c to r responses are a p a rt o f t h i s type o f le arn in g .

A p o ssib le e rro r in th i s and sim ila r stu d ie s

i s dism issed on page 38. The re la tio n s h ip o f k in e sb h stie perceiving mid motor coordinations i s of considerable I n te r e s t to t h i s and a l l stu d ie s involving perceptual le a rn in g , but i t i s not w ithin the scope o f th e p resen t in v e stig a tio n .

One in v e stig a to r

(Chase, 18) has attem pted to demonstrate th a t k in e s th e tie s lu e s a re superior to v isu a l when the two are equated and when measured e ith e r su b jectiv ely o r o b je c tiv e ly .

Chase

f a l l s in lin e w ith th e peroeptual task view when he d i f f e r s a tia te s mass le arn in g a s a 'c e n t r a l o rg an isatio n o f Id e a s '. Cook's extensive stu d ies o f b il a te r a l tra n s fe r began

13 w ith t b t use e f a m irro r t r n o d s t a r learn in g problem (13). V isual perception «*a given e x tra heavy w eight, since every su b ject was allowed some k in e s th e tic and/or a s t e r imagery experience beforehand w ith th e v is u a l learn in g fo o ter re* moved,

This wan accomplished by having su b jects tra c e th e

p a tte rn seven times by d ir e s t v isio n (no m irror) before s ta r tin g th e le arn in g proper.

Thus when le a rn in g was s ta r te d ,

the m irro r Illu s io n was added to a p a rtly e stab lish ed h a b it, emphasizing the peroeptual q u a litie s o f th e ta sk .

Me eb-

ta lc e d a tra n s fe r o ff s e t of 89j*> to the opposite symmetries! o u sels group, a fig u re even la r g e r than th a t o f Mtaroh.

th is

comparison i s in te r e s tin g , since Cook* e c o n tro ls were ado* quote and elab o rate.

Zn a follow-up study, t h i s same worker

(14) showed th a t w ith the m irror tra c in g ta s k , the amount of tra n s fe r i s roughly p roportional to the amount o f p ra c tic e . Cook's fo urth oeamnnleation (fo r 111, see page 81) i s a soaparlsen between perceptual ta sk s a t two le v e ls o f r e ­ finem ent.

Sixty su b jeets ware stu d ied fo r hiutd to hand tra n s ­

f e r on th e m irror ta sk and sixty-tw o fo r hand to hand tra n s ­ f e r w ith a blind fin g e r mass wader sim ilar co n d itio n s.

Un­

fo rtu n a te ly , th e r e s u lts are cot toe c le a r sin e s a "change e f Method* on the p a rt o f the su b jects in on® group tended to in te r f e r e .

Comparisons are th e re fo re net p o ssib le.

The

fundamental problem was the permanence o f tr a n s f e r , and th e conclusion was th a t p raetlo e t r i a l s were s t i l l e ffs o tiv e even a t th e end e f 30 tra n s fe r t r i a l s .

14

tamy W a lso made m in te re s tin g comparison between b w type# o f peroeptual practice*

Woodworth {??) had p rc -

v iw s ly shown th a t throwing d a r ts a t a ta rg e t could he tra n s ­ ferred*

th e ta sk here was jabbing a t a ta rg e t with m irrored

vision* and the tr a n s f e r was from hand to i p s i l a t e r a l foot* A co n tro l group p ra c tis e d only with the footf experimental group A f i r s t p ra c tise d with th e hand*

Experimental group

1 Ptaotwed no hand p ractise* but were given thorough verbal in s tru c tio n in th e methods ©f performing th e mirrored task* and i t was demonstrated to than*

th e p ra c tic e group (A)

stewed more tra n s fe r than did th e In stru c te d group (B), a l­ though both experim ental groins were superior to the sen* tvwt group*

Ira y found in th is study (ItSS) th a t lengthen*

ing th e p ra c tic e did mot improve th e amount of transfer* nor mmm th e tr a n s fe r e ffe c ts c a rrie d very f a r in to the tra n s f e r series*

th e re s u lts o f §mk t,

, where El i s the f i r s t

30 t r i a l « f th* p ra c tic e a e rie s , 1.2 i s the p a s t-p ra e tlc e t r i a l , and RIO i s the l a s t t r i a l of th e p rao tio e s e r ie s .

Cook (1?)

.has reeemputed the r e s u lt s o f I r a ; (7 ), Davis (D3), and Vieg (73) using t h i s teohnlqua.

i l l show r e s u lts ramaifeably

elo se te th e SO)» Cook him self has obtained. i t ones th e questions may he ashed, *®hy have pro* p ra c tis e t r i a l s (o r tr ia l} a t a ll? " a sin g le p o s t-p ra c tic e tr ia l? "

and "why have more than

Although th e p rs -p ra e tle a

t r i a l i s ignored s t a t i s t i o a l l y , i t s t i l l serves as observe able evidence th a t th e l e f t hand sag formerly in f e r io r to i t s p o st-p ra e tio e a b i l i t y ,

hashing th is assuranee, th e only

a lte rn a tiv e i s to re tu rn to h ra y 's method of oontrol groups, which mould mean equating.

As to the seeond question, p o s t-

p ra e tle e t r i a l s beyond one a lso serve as observable, even i f u n trea ted , evidence th a t ohanes performance i s not r e the tra n s fe r i s reasonably permanent* Cook's method seems to be th e most s a tls fa o to ry in obtaining an aseu rate measure o f th e o ffs e t o f opposite p ra c tic e alone, and i t w ill th e re fo re be used in th e experi­ mental seetio n of th e p resen t investigation* SBie M amolaar o f ^ l a t e r a l Tra n a fe r.

Most o f the informa­

tio n r e la tiv e to th e ro le of the nervous system in tran sfe r problems i s o f a e e e sslty I n f e r e n tia l ra th e r than experimen­ ta l*

An exception i s the work of lashley, which oan be

f i t t e d in to the general framework o f the problem,

Especial-

31

I f im portant la th e eebus monkey experiment where p a ra ly s is o f th* responding members apparently did n et in te r f e r e w ith th e tr a n s f e r (see page i3f).

There in

a

strong need f o r

s im ila r experiments with various e th e r so rt* o f ta sk s. Following th e e a rly lead s in conditioned response ex­ perim ents, Anrep (1) speaks o f th e tr a n s fe r o f the t a o t i l e stim ulus effe c tiv e n e ss to various areas in to m e o f c o r tic a l spread {“neural irra d ia tio n * ).

In d iscussing the r e s u lts o f

Nororoos, B il ls (4) a lso suggests some form o f in te r* hemisphere neural ir r a d ia tio n ,

lie s ta te s in p a r t. *Ths s i t e

o f th e gain in th i s and a l l s im ila r experiments seems to eeapel th e hypothesis th a t when th e l e f t sid e o f the b rain i s being exercised, th e rig h t i s sim ultaneously exercised, or

(tee

th a t th e c e n tre ! p a tte rn i s g en eral, and independent

o f e ith e r hemisphere alone.*

i t i s p e rtin e n t to the hypo-

th e s is to be sta te d p re se n tly th a t both o f th e se fu n ctio n s may have some bearing; upon the neural mechanisms involved. A sim ila r neural theory ie used by Freeman (33) to explain th e absence of gains in th e tra n s fe r o f fa tig u e as p ra c tic e periods in creased .

F atigue e ffe c ts from a l i t t l e

p ra c tic e on th e rig h t w ill tr a n s fe r to the l e f t , but In­ creasing th e amount o f rig h t work w ill not produee r e lia b le in sreaae s in th e amount o f tra n s fe rre d fa tig u e .

The phe­

nomenon i s in te rp re te d to be a function o f a progressive d is s ip a tio n o f neu ral a c tiv ity throughout c o r tic a l a re a s . One sp ecia l problem in b i l a t e r a l tra n s fe r receiv in g

92 considerable popularity t e l a curious neural theory involved e i th e r by statem ent o r by im p licatio n .

As & s e t t e r o f feet*

t k l i sp e c ia l problem goea baek to Weber*s o rig in a l observe* tie n in 1244 whieh »arked the beginning o f e l l in te r e s t in th e la r g e r problem*

t h i s le th e question o f m irro r w ritin g ,

• r in i t e so re frequent experim ental fora* th e tra n s fe r o f m irrored sane patterns*

th e handw riting problem* in whieh

ch ild ren {e sp e c ia lly ch ild ren with sp e c ia l handicaps) a r t found to be q u ite f a e i le a t 'w riting a m irrored image o f nor­ mal w ritin g , h a t been investigated, by F u lle r (99) end by Fial&ee and byere (9 1 ), among others* From observations on high grade m entally d e fe e tir e c h ild re n , Fleldee (90) s ta te s th a t row ersale are e s p e c ia lly asso ciated e lth th e use o f th e l e f t hand *in oases in whieh (1) a r i$ h t head mowement i e repredueed sim ultaneously w ith th e if© hands and (2) a movement learned and preotioed w ith th e rig h t hand i s reproduced w ith th e le f t * . l a regard to the move in tim ate r e la tio n o f m irrored responses to b il a t e r a l tra n s fe r {or v ise versa)* th e re a re a t le a s t th re e ooamunieatlons in th e lite ra tu re *

Freeman

(36) had h ie th ree su b jects p ra e tio e a t f a e i l i t y in w ritin g th e alphabet.

He found th a t th e tr a n s fe r o ffs e ts mere g re a t­

er fo r one l e f t handed subJset when he was allowed to w rits in a reversed (m irrored) fashion w ith the tra n sfe rre d hand ( th e .le f t) .

One rig h t handed su b ject Shoved the g re a te s t

e ffe e te under p ra c tis e eonditione o f forward w riting w ith the

S3 l e f t « n i reversed w ritin g tra n s fe rre d to th e r ig h t,

one am®

M d u tire u s eubjeot showed l i t t l e preference f o r fe a r d i f f e r ­ e n t p ra e tio e (tuft tr a n s f e r p a tte rn s .

Again he I n te r p r e ts in

terete o f ir r a d ia tio n , an& says, *©ur r e s u lts suggest th a t tr a n s f e r e ffe e te In eoordimated movements a re a fra c tio n of n eu ral ir r a d ia tio n and f e llo e ressg n issd p rln e lp le e o f b il a t e r a l eendaetiea*” lard** more thorough study o f 'th e sane problem {68} 'had been published too years p r io r to freeman* s .

ssubjeets

v e r t high great' mental' d e fsetiv ee (hoys, mean age 13*#, mean X«Q» 66} oho were required to le a rn a b lin d fin g e r mass, b i l a t e r a l a b ility was then measured using both (1) the seme mate and (?) one' o f a reverted p at te n t.

This tank, aooord-

la g to VMM, " le c h ie fly o r ex clu siv ely la terms o f muscular ■memory*,

th e r e m i t s 'a r e in te re s tin g ' in t h e ir v arian ce, for

rig h t handed ohllOroh, d ir e s t p a tte rn s shoved su p erio r tra n s ­ fer*

f o r ambidextrous children m irrored tr a n s f e r m s good,

but d ir e s t p a tte rn s gave seme ln d ie a tio n o f negative tra n s ­ f e r i n term s o f t r i a l s saved*

f o r l e f t handed children

(w ith whom m irrored w ritin g i s most frequent) tr a n s fe r frost r ig h t to l e f t was good f o r th e m irrored p a tte r n , poor for the d ire s t} 'from l e f t to r ig h t m s good fo r th e d ir e s t trans­ f e r and. p e e r f o r th e m irrored.

The author*e in terp retatio n s

a re meager, but he th in k s th a t th e re i s some support f o r the hypothesis th a t m irrored w ritin g i s caused by p ra c tic e in d ir e s t w ritin g by th e opposite hand,

th e se d a ta are eotnpll-

34 oated by te * n atu re o f te * subJeat■—Ward adm its te e prcbls® e f s& lataining te* subject* a atten tio n *

C lear in te rp re ta ­

tio n s BllX probably su ffe r from want o f a b e t te r knowledge o f te * am m leg y o f han&edneaa.

in c o n tra st to tees* r « -

• u lte a re eon* in c id e n ta l observations o f f la g (73) eiileh t e r te* p o st-p ra e ti* * performance o f a m irrored p a tte rn over a d ir e s t p a tte rn . I*** date, a t* inconclusive, and only " tra n a fe r sec**** a re given,

te*** a re apparently te* raw soores o f te* post*

p ra o tle e s e r ie s , w ith no reference to e ith e r th e p re -p ra o tis e le v e l o r te * amount o f learn in g ,

t e l a study nay serve a s m

e x cellen t example o f te a sev eral poor attem pts in te* f ie ld . An In v e stig a tio n by M illa*a and Van R iper (te ) l a te * n e a t re s e a t a tta c k upon te* m irrored ta sk cueetion.

And here

esa be found te e n e a re st approach to an exact statem ent o f te* p o s itio n regarding neural theory im plied in a l l such stu d ie s,

they speak o f te e p o s s ib ility o f b i l a t e r a l tr a n s f e r

being « function o f a formation in te * opposite c o r tic a l hemisphere "of a n lr ro re d rep resen tatio n of a learned p a tte rn o f muscular aoveaonta*.

te es* authors r e f e r to several p r io r

studies, (but not Ward, nor flo g , nor Freeman) in support o f te e hypothesis, but a l l such support i s somewhat in d ire c t, a i l i s s n end Van hiper*s study end* us* o f two groups of sub­ j e c ts learn in g to n e g o tiate a b lin d sty lu s mase te e p a tte rn to a clo v er le a f (te r* e jo in in g , b u t in ­ complete c i r c le s ) .

Each subject (co lleg e student) m s te s te d

38 f o r both r ig h t end l « f t hand a b i l i t y , and In both a d e c k ­ e l a* and a countsr-oloekwls* d ire c tio n to r e&ah hand (p re p ra c tic e s e r ie s ) .

One group wee then tra in e d on th e r ig h t

la a clockwise d lre o tle n , th e o th e r group on th e rig h t l a a oounter-oleekwlee d ire c tio n .

P o c t-p ra e tle e te a ts showed

th a t th e r ig h t hand gained in a b i l i t y in both d ire c tio n s , but considerably more gain was shown in the tra in e d d ire c ­ tion*

(Sains were a lso shown fo r th e unpraetleed hand, but

here considerably so re gain m s shewn in th e untrained d ire c ­ tion* th e neurological p ic tu re o f m irrored response p a tte rn s i s made none too. clear*

One would suppose th a t as th e r ig h t

hand were moving forward in a p a r tic u la r p ra c tic e response, in te « o te w hmitffamm

te l t e imSU tvmfea&Mr

f f t m n m vm m t tatewai*!® in tee

l e f t feMft* In tee## nfn&iei tee

effect

to

rif£ht*ieft im M m tt* tout* etxtingeif raoughi not to forwardbackward re la tio n s h ip s .

Any such theory seems badly lacking

in support, e sp e c ia lly in view of the c o n tro v e rsia l s ta tu e o f costal csural connections*

Reason (S t) e a rly stated th a t

•th e m ajority of th e c a llo s a l fib ers do not connect to g e th e r

symmetric p o rtio n s o f th e cortex*,

on the o th e r hand, T il-

aey cad R iley (64a) re p o rt th a t they do* In n e w o f th e nasty discrepancies of re s u lts and th e taxing o f c re d u lity in accepting the theory as advanced by MUisett and Van R iper, i t would lik e ly be w ell to look e ls e -

36

i b m le explain t h e i r demonstrated d iffe re n c e s. M

op p o site

asfcivit¥ su b je o tiv sly ooneidsred 1* J u st a s com patible

whether I t b« ex aetly sim ilar i s produet o r sim ila r in th e fu n ctio n al p a tte rn o f musole co n tractio n (reversed p ro d u ct). Thus the schoolboy can p a t h is head and rate h ie abdomen e i­ th e r with both hands up sim ultaneously o r with one up and th e o th e r down a t a given in s ta n t, and with equal ©&&©{ i t l e then one movement becomes d if f e r e n t th a t coordination breaks down.

The sovlee drummer e&n o perate two s tic k s el*

th c r sim ultaneously o r a lte r n a te ly , but two d iffe re n t rhythms a re reserved fo r a l a t e r lesso n . th e o rie s o f T ransfer,

th re e thooretio& l co n stru ctio n s o f

th e tr a n s f e r process have been considered by various iavos* tig s to rs .

two of th e th re e have reeeived almost a l l o f Hie

eH perluental c o n sid e ra tio n , and these are th e two whieh a re a le e Involved in th e edue&tional problem of tra n a fe r o f training*

Along w ith th e extremely d i f f i c u l t te c h n ic a l

lim ita tio n s , th is unfortunate re la tio n s h ip w ith education la fo r lack of ooneideration of the th ir d theory. Usually c la sse d under th e ru b ric of Id e n tic a l JtiLfir menta. th e f i r s t theory i s r e a lly a manifold theory.

The

arguments and counter arguments as te the siz e and nature o f an element are now ol&ssie*

Confusion o f th e w ild est

S *rt s t i l l m ists * Id e n tity i s v ariously used to in d ic a te only (1) s im ila rity o f stim ulus, (2) s im ila r ity of response,

m or. i&i s im ila rity o f neural "u n it"

op

pat ta rn .

Bmilap (S6) t r e a t * id e n tic a l elements • • p ercep tu al TO#S^i49#0f of wtdeb th e re i s m id e n tity fo r performance o f e ith e r bend*

In diaouesiag th e study o f to re ro os, lie f e e ls

th a t th e r e s u lts J u s tif y th e highly e r i t i e s l statem ent th a t " b ila te r a l tra n s fe r i s n et tra n s fe r a t a l l , a t le a s t not t e Hunter (43) recognised in 1929 th a t "we are s t i l l f a r frost a s a tla fa e to ry explanation o f the f a s ts o f transfer** o f id e n tie a l element®—elements whieh are id a n tie a l " in th e fe m e o f response concerned", h at a t th e m e tin e he adm itted th a t " i t l a a l l h a t im possible to being th e theory te a rigorous experimental te s t* ,

suoh a

e ls e o f id e n tie a l elements any he brought in to elo ss re la * tlen eh ip with th e th ir d theory dis«assed below.

Woodworth

(79) also eoggests th e importance o f responses eomaon to the sSSiitoSSsM* Freeman (94) attempted an experim ental ehaeh on fh e rn d ik e 's theory o f n e u ra l elements,

th e problem was tr a n s f e r

o f tra in in g ra th e r than b il a te r a l tra n s fe r, hut " l i t t l e o r its evidence o f n eu ral id e n tie a l elements were found by chang­ ing the e ffe c to r, re c e p to r, or e e n trs l a d ju sto r u n ite em­ ployed l a th e task**

E aton's (99) in te rp re ta tio n of th e

id e n tic a l sle e e a t seeiae to he neural*

h llis e n and Van Hiper

(Aft) speak o f "m irrored iaslte~gram«* as a theory beyond th e usual th re e , but th i s use o f T ro laad 's term seems to be a

m Q M l U l CASS O f * C le m e n t* " «

Cook (XT), in presenting a lengthy d iscussion o f IN) th e o re tic a l problem, reoegnised th e confusion regarding e le ­ ment* and r e fe rs to Id e n tity In to m e o f th e stim ulus p a t­ te rn , re c e p to r adjustm ents, and p o s tu ra l set*

Although he

adm its th e p o s s ib ility o f ir r a d ia tio n a s a n eu ral fa c to r, he d iscard s the use o f a neural u n it as an id e n tic a l element. Horeroe* (B7) had designed h ie experiment in an at* tempi to is o la te various fa o to rs in o rd er to determ ine j u s t s h a t the id e n tic a l element might b e.

Although h is r e s u lts

are not dependable, i t does seem evident th a t a l l o f the p a r ts of th e t o t a l ta s k which he studied served some func­ tio n In both th e p ra c tis e d and the tra n sfe rre d task*

Bray

(7) had a sim ila r Idea m mind when be gave to one group o f su h jeets thorough verb al in s tru c tio n s concerning th e pereeptu a l fa o to rs.

Compared to a second group who *learned by

doing* th e in stru c te d group were su p erio r a t f i r s t , poorer l a t e r , in th e tr a n s f e r s e rie s ,

" i t may be th a t o th er fao­

to r s (elements) than those on which in s tru c tio n were given are p resen t in tr a n s f e r ," he eoneludee.

In th ese two stu d ­

ie s as w ell as th a t o f S llpola (page

th e re e x is ts an er­

12)

r o r in assuming th a t p ra e tie e i s equated fo r th e two s e ts o f co nditions, verbal in s tru c tio n and motor p ra e tie e . Cook b eliev es th a t h is r e s u lts and those of »icg whieh shew th a t the amount of tr a n s f e r fo r a m irror v is io n ta sk i s approximately the same as fo r an Irre g u la r b lin d

38 mass, d* in d ie a te th a t tra n s fe r e x is ts even when id e n t i t i e s ( a t l e a s t v is u a l id e n titie s ) a re removed.

Hence t h i s serves

a s negative evidence th a t auofa id e n tit ie s a re e a s e n tla l to tr a n s f e r ,

l a follow ing up th e aforementioned d is tin c tio n

between a perceptual ta sk and a motor ta sk , i t la la good order to suggest th a t euoh M o n title a are e s s e n tia l to the fonsert they are perhaps s u p e rfic ia l to the l a t t e r .

They

a re im portant to th e tra n a fe r of-m irror'draw n fig u re s, e ls e Hall* a r e s u lts would not have been as they were (page l4f) t they are eeasiderably lo s e im portant la the tr a n s fe r o f a meter S k ill,

Along w ith Cook, then, i t is w ell to seek e ls e ­

where fo r a f u l l e r explanation. Many In v e stig a to rs have aeoepted the fa o t th a t the subject may v e rb a lis e a g e n e ra lisa tio n o f methods, o r o f M aas p e rta in in g to the task reg ard le ss o f the body member responding.

She eeeoad o f th e th ree th e o rie s i s u su a lly re­

fe rre d to th e re fo re a s Me JBHMaaftlgKSte JfoflMHh and i s c re d ite d to Judd.

bray (7) noted with b is f i r s t experiaen-

t a l groups th a t t h e ir geacral a ttitu d e , fa m ilia r ity , e t c . , seemed to tra n s fe r,

"th e ex p la n a tio n .. . .probably l i e s , in

p a r t a t l e a s t , to Me tra n sfer of methods whieh have heea learned fo r one p a r t o f the body a re o arried over to prac­ t i s e with some other part.*

#u»n (56) thought that for h is

su b jects “the method learned w ith the p ra c tis e d member is o a rrie d over to Me noa-praotloed one*.

Wieg (73) f e l t M at

th e f a s ts o f h e r r e s u lts "in d ic a te th a t the tra in in g operat-

40

la g in l&e le arn in g a t th e problem was a t a general ra th e r than a e p e e lfie n a tu re * .

Eaton (87) believed th a t one o f

h ie aab»gre«p* tra n s fe rre d bjr way a t the ‘agoney* of lie n * t l e a l elements while m o th e r used th e "agency* o f general!* n atio n , hut "elements* fo r Eaton are perhaps more c lo se ly el* ! ! • ! to the th ird theory discussed below. follow ing th e treatm ent o f B reltw ieaer (8)» the two th eo ries o f g e n e ra lisa tio n and Id e n tic a l elements are o fte n

considered complementary element theory.

and are combined in to th e ooiamoa

This teens reasonable, tlnee th e ir d i f f e r -

enee I s merely a n a t te r of th e "else" o f the u n it considered* While l a one ease th e u n it la a method o r a m otive. In the o th e r I t le a stim ulus u n it, o r the perception of th a t u n it, o r the response to th a t u n it, o r th e neural * trace" involved l a eueh a response—as you lik e . Stanley (69) has taken an observation of Bray*s (?) th a t in s ig h t must be present before tra n s fe r ocours and in ­ corporated th e .re su lts o f tr a n s fe r in to h is organlsstis theory on th a t basis*

This might be considered a sp e c ia l ease o f a

common element th eory, although Wheeler* a system i s h eav ily leaded w ith neu ral co n stru cts alee*

The organ!sale i n t e r ­

p re ta tio n I s s ta te d by wheeler as follows: The learn in g I s a co n fig u ratio n al process In­ volving in s ig h t in to th e t o t a l s itu a tio n . In­ so fa r as th a t s itu a tio n i s not a lte re d by the eondltlons o f tra n s f e r, th e in sig h t i s s u f f ic i­ ent to guarantee continued performance. When th e tra n s fe r involves the development o f a new

43.

type o t configuration th e performance suf­ fer®. Any o t t e r lo s s observed in the tra n s ­ f e r depend® upon lim itation® inposed by the anatomy o f th e p e rt o f the body to sh ieh the tra n s fe r le node* (09, p. 306} Cook (1?) tak es v io le n t objeotion to t h i s view*

In

th e f i r s t p lace, ©r»y*s eontentlon th a t only in s ig h tfu l learn in g transfer® i s - i n e rro r.

Woodworth (77} had made a

*pn»-ingight period* observation th a t only su ccessfu l pr&et i e s 1® found to tra n s f e r .

This i s probably th e same th in g

i a d if fe re n t s lo th in g , but i s no more c o rre c t,

hot only

has Cook shown th a t the amount o f tra n s fe r bear® a d e f in ite re la tio n to th e amount o f p ra c tic e (page 13), but he also state® th a t Ewsrt*s d ata shew tr a n s fe r from only one t r i a l o f p ra e tie e (17).

In view o f these f a c ts , Cook disposes o f

wheeler* a p o sitio n a® follows! Sf only the learn in g due to in sig h t tr a n s f e r s , th e re must be a n o n -in slg h tfu l kind o f le arn ­ ing whioh doe® not tra n s f e r. His (fheeler* ®) explanation o f th e incompleteness o f tra n s fe r i a term® o f 'anatom ical and th erefo re mechani­ c a l differences* between th e limbs merely avoids the is s u e , fo r i f th e in s ig h t gained In the f i r s t ten t r i a l s alone tr a n s f e r s , what 1® th e n atu re o f the le arn in g in th e succeed­ ing f i f t y tria l® (Bray*e data)? Xt must be a a c n -ln s lg h tfu l leashing s p e c ific to a p a rtic u ­ l a r p a rt o f the b o d y ..* .. N either g e n e ra lisa ­ tio n nor in s ig h t can be & complete explanation o f tra n s fe r. (17) Xt i s fo r Ju st exactly th i s reason th a t th e th ir d theory o f b il a t e r a l tra n s fe r has developed.

Furthermore,

i t 1® highly p o ssib le th a t th e re may be some learn in g "spe-

m e i f i e to ft p a r tic u la r p o rt o f th e body*.

Kumerouo sugges­

tio n s may to found, *o f a r book in the l i t e r a t u r e &a *. f* Davis ia 1393 (33), th a t some tra n s fe r e ffe e te may be duo to a c tu a l p ra c tic e o f th e so -called in a c tiv e member,

SuCh

ft theory has varioua names ’a pplied to i t , but im n lla it jgBOb tlofe i s a s s a tis fa c to ry as any.

I t i s in te r e s tin g to note

how numerous have been th e suggestions o f th e importanee o f t h i s fe e to r, and how l i t t l e have been th e experim ental at* t&oke upon i t , f i s s l a r and Richardson in 1900 (74) dleeuesed th e p o s s ib ility a t some le n g th , and made sons attem pts to meas­ ure im p lic it a c tiv ity by means o f tambours attached to th e s u e d e # involved,

t h i s was not a lto g e th e r unsnooessful,

etnee th e d a ta did show *an s e tn s l contraction o f th e r e ­ la te d wuseles of th e same sid e corresponding to th e observed p ra e tie e e ff e e ts i end since th e p ra c tic e e ffe c t appears upon th e o th e r side a ls o , i t i s n a tu ra l to in fe r th a t those muscles contract*.

This i s , o f course, ra th e r basy reason­

in g , b a t th e suggestion i s p resen t n ev erth eless.

Following

th e tendency o f speaking of tr a n s f e r In te w s o f a change In the motor c e n te rs o f the opposite sid e , and assuming th a t th e re i s ft Change in th e motor cen ters on th e learned sid e , they comment th a t * it i s d i f f i c u l t to see how such a change, re s u ltin g in a co n tra ctio n , could be tra n s fe rre d to another c e l l (on the opposite side} without re s u ltin g in a contrac­ tio n o f th e muscles with which t h i s second c e l l holds fune-

43

tli«M& P*aaUoa«hip*. B S tft (04) adm itted th e p o e e ib ility o f a ‘p e rip h e ra l change* on l i t o p p o site aide* but even by 1928 th e re bod 6««

*00

evidence advanced to' shoe th a t asso ciated movements

o f th e so«eailed m a u d p a rt ore o f say importance ia tr a n s fo r* , aeeordlag to tr a y (? ).

Dunlap

(as)

fe a r years l a t e r

continued to o a st doubt upon th e sig n ific a n c e o f sueh move* n e a ts.

l e doee admit th a t th e re any he some oorrespending

p ro cesses, hut » if they oeeur (they are) too s lig h t to per* n i t r«e®»ding w ith pneuaatie devices applied to th e non-used hand and f in g e r s .« . . .

In any eaae the a c tu a l p ra e tie e o f-

fo o t on the non-used hand must he so minute as to have no bearing on th e re s u lts * .

In a lik e vein i a Kuan's ( is ) eon-

elu sio n regarding observations o f subject# le arn in g th e t a l l * in-a-eup tr le k , th a t " in c ip ie n t movements o f the unused hand probably co n trib u ted something te th e amount o f tra n s fe r (h u t i t i s ) of s lig h t importance*. IO U h b and Van h ip er (85) concluded th a t explanation o f t h e i r findings could he made only on s h e e ls of opposite bead p erip h e ra l n a tiv ity o r by c e n tra l fa c to rs correspond­ ing to i t . b ility .

B ills (4) makes pro v isio n fo r th e l a t t e r p o ssi­

wieg (73) g iv es f u l l recognition to th e theory o f

Im plied! a c tiv ity , and suggests th e early stu d ie s of Davie end o f tooduorth as "supporting evldenoe*. Eaton (27) in 1938 regarded im p lic it movements as *ueh a strong p o ssib le f a s te r in tr a n s f e r th a t he attem pted

44

to ex ercise a c o n tro l over I t .

One group was allowed fre e ­

dom o f th« tra n s fe rre d band during opposite hand p ractice} th e e th e r group bad th e ir tra n s fe rre d hands re s tra in e d by blading to a f l a t board during th e p ra e tic e .

This lim ite d

only gross movements, but Baton believed th a t In c ip ie n t move­ ments were a lso elim inated beoauss •most su b jects rep o rted th a t t h e ir bands vent to sleep".

This I s h ig h ly question­

able* .also# th e phenomenon mentioned i s a sensory event and prevents n e ith e r im p lic it nor g ro ss movements fo r th a t mat­ te r.

At any r a te , th e re was a marked d ifferen c e between

c o n tro l m& experim ental sections o f each of h is th ree sub­ groups# .and I t appears th a t the laboratory co n tro l did have a marked Influsnee on tb s d if f e r e n tia l performance o f th e two groups.

The experim ental groups (re s tra in e d unused

band) tra n s fe rre d le e s m an d id th e co n tro l groups when sub­ je c t s had .etc knowledge o f r e s u lts , but they also leam c^ lo s e .

Eaton recognised the p o s s ib ility o f an uncontrolled

tr a n s f e r from the p re -p ra c tic e to the p ra c tic e s e r ie s , and assumed th a t i t was equal fo r a l l of h is sub groups.

He

dees not seem to reoognlse th e n ecessity o f re la tin g the amount o f tra n s f e r to th e amount o f le arn in g .

The subject’s

ta sk vac measured in th e amount o f e rro r (see page 22f for a d e a e rip ito a ), although a t one p o in t these d ata are referred to as an "e rro r score" and in another as th e "number o f er­ ro rs* . l a reworking the d ata of another experimenter there

4$

i s o fte n danger o f m isinterpreting and taking u n fa ir sdvafitags*

Even m$ some Interesting comparisons arc sometimes

derived#

As previously stated (page 30), Coot revised the

figures from several experiments according to h is formula ltd to shows the percent of learning which is transferred* I t i s p articu larly d iffic u lt to do that with Eaton1e data# since the only figures given are averages of 100 t r i a l units* the order of procedure was (e*g») 100 t r i a l s l e f t j 6 see* clone of 100 t r i a l s each, rig h t| 100 t r i a l s left*

His com­

putation of tran sfer was simply the percent of improvement from the mpvmm of the pre-practice to the avera&e of the post-praotloe series*

As stated in an e a rlie r section# th is

te c to lip f is known to Include more than the effects of trans­ fe r, ant especially so when 100 t r i a l averages are used* ffee necessity of working with successive t r i a l averages# rath er than single t r i a l averages# Is also troublesome in applying 0ookf s formula# but the erro r re su lts In making the percentages a l l higher than they would otherwise be* In sp ite of these recognised d iff ic u ltie s , the accompanying table presents some strik in g comparisons* Somparieons of absolute amounts are not Intended in view of the possible errors*

l e t i t may be pointed out th at

the revised percent tran sfer for group X—where conditions are most sim ilar to the ordinary tran sfer situ atio n —the figure of 83$> is ju s t about the same as for many other stud­ ies*

Comparing the experimental with the control groups

46

E ato n 's

$rewp 4 X ft

C onditions o f Experiment

Hand restrained lig h t to l e f t Ho knowledge Hand free Eight to le f t Ho knowledge Hand restrained heft to rig h t Ho knowledge Hand free rlghi heft to rig ht Ho knowledge land restrained reetJ Eight to 3 le ft knowledge freee Hand fre Eight to 3l e f t knowledge

f Transfer

According to Eaton

$> Transfer

with Cook's

Formula

26

106

m

86

21

101

81

97

1

-1S9

40

222

under no knowledge eonditlons {a with x and 8 with 1} i t i s clear th at th e ir re la tiv e differences of tran sfer are nulii*

X&M JX Ml MteWJULZMESESaS* I f these revised finding® can be accepted as of any l^portaneefi i t would seem that the probable effect of the control of binding th e hand served as a d istra c tio n rather than a m m inhibition of transfer*

This i s evidenced by

(1) the fact that the learning of the experimental groups

wm le ss (as well as tran sfer being le s s ), and (£) the most probable effects of working with one hand "asleep*, ma most subjects reportedly did# Revised differences between con-* tro l and experimental groups are not subject to rigorous

47

tMfttMftt* ©nd explanations of differences, which say o r may

m t bo significant differences, are moat hazardous.

the two

"Imowledge* groups arc p articu larly doubtful as to Interpreta t ion*

bine® Eaton had noticed a tendency toward movements

of tH« non-practicing hand of subjects in the control group, ho in c lu d e s th at *apparently tra n sfer for the control group was through the agency of id en tical elements**

The

elements her® must then, be some so rt of M neural bond* and/or

muscle tensions*

fo r the experimental group where movements

were psvportsdly restrained, he thought that tra n sfer was by way of the "agency* of generalisations* Although th is study i s the nearest approach to an ex** perlmental Investigation of the th ird tra n sfer theory, I t cannot be reasonably accepted as throwing much lig h t on the problem in view of (1) the questionable effect of the lab­ oratory control and (2) the revised comparative values of the mount of learning which was transferred* b* Development of Hypothesis*

*fhe Problem

In the la s t of five communications, Cook (17) offer© a rath er complete evaluation of these various theories*

In

addition to those mentioned heretofore, he also considers the p o ssib ility of an application of the Wiley-Bruce stimulusresponse theory to b ila te ra l tra n sfer, but i t too is rejected. Mot only is the reader le f t to feel that none alone Is a satisfacto ry explanation, tout that any combination s t i l l

48

leav es gaps in our understanding o f th is phenomenon.

Cook

him self ap p aren tly d iscard s or a t la a a t shelves an a t t a i n t a t th e o re tic a l p ro g ress. he w rite s .

“Our program la mush more modest,"

“I t c o n s is ts l a attem pting to discover some

fa a to ra In orose-sdusation, and ooaparlng those fao to ra w ith the conditions governing o th e r forma o f learn in g * ” Again ha p o in ts out th a t “th e o ries of oroes-edueation oan ha no h atter* a t heat* than our understanding of the n atu re o f the o rig in a l le a rn in g ". t h i s viewpoint may be granted and even applauded, y e t I t l a d i f f i c u l t to g e t away from th e truism th a t theory and em pirical findings progress sim ultaneously w ith mutual bene­ fits *

C ertain o f th e In v e stig a tiv e findings reviewed above,

in the lig h t o f the organisation aoeorded to them, suggest th e p o s s ib ility o f a somewhat new approach to the problem. H esuits l a learn in g reaearoh and re la te d problems fu rth e r th e p o s s ib ility .

F in a lly those re se n t stu d ie s o f th e r o le

o f p erip h e ra l a c tiv ity in various psychological segments give a le a d fo r reopening study upon the o f t mentioned but seldom emphasised theory of Im p lic it a c tiv ity . th e observations of Cook may again serve as a p o in t o f departure.

In h ie th ird study (IS) where he measured

tra n s fe r o f a non-visual task ha pointed out th a t th e re were two p o ssib le learn in g s e ts a v a ila b le to the subjeot.

Either

they may "&) le a rn to re la x a l l muscles exoept those neces­ sary to move the hand and pay more a tte n tio n to ex tern al

49

s tim u li (th e sid e s o f th e p a th ), o r (8) they may grow inde­ pendent o f th is sensory data and then le arn in g la la rg e ly th e formation o f a u n itary k in e s th e tic p a tte rn * .

In th e

flffttt « * » , the su b ject ia making th e most o f what U n ite d perceptual fa c to rs are a v a ila b le to h in t in th e second, he l a attem pting to develop a p a tte rn o f movements.

Hie f i r s t

i s a function o f th e perceptual aepeote o f a ta s k , th e sea* aid a funotian o f th e motor aapeete.

Both are stim ulus-

response s itu a tio n s , but the f i r s t la a n a ly tic a l—and per*' ta in in g to d is c re te stim u li { the second l a sy n th e tic a l—aM p e rta in in g perhaps to th e G e sta lt o f th e s itu a tio n .

In th e

one case, a subject i s atten d in g to th e o b je c tiv e and meter* a a l s tim u li.

la th e o th er ease, a subject l a attending to

an image fo r chloh s u b s titu te stim u li nay serve as th e in i* tia to r. »*xeept fo r a few su b jects in e a rly t r i a l s , in d ie a tloiss a re th a t learn in g i s o f type two above,11 Cook w rite s in regard to th e b lin d sty lu s n&se problen.

Thus fo r such

a problen, learning i s somewhat d if f e r e n t than i t would be fo r m irror-draw ing, fo r example.

I t must be c le a rly under­

stood, however, th a t these two fa c to rs in a l l lik elih o o d never can be said to be mutually d is tin c t.

In a l l p ro b ab il­

it y th e re i s some importance to images and G estalten f o r the m irror traced s ta r .

There a lso may be perceptual fac­

to r s on th e o th er sid e of Hie p io tu re .

S ubjects tra c in g th e

b lin d mass oould not have been responding wholly to th e image

so a s a stim ulus i f we Awe accept th e work o f Levin (5 3 ), who shews th a t re p e titio n s o f a k ln e s th e tle a lly derived p a tte rn otlX 'She* successive also co n tra c tio n s, even th o u # th e p at* tana remains f a i r l y accurate.

Moreover, ha shows a high

percent o f tra n a fa r of thasa laa§ee—higher whan v is u a lly derived than whan k in e s th e tio a lly derived,

Thera l a l i t t l e

evidence of any a lg a lfle a n t tra n a fa r In the o th e r d ire c tio n —from k in a a th e tle a lly derived to v is u a lly imaged.

S eeker'g

su b jeets {&) could not give in tro sp e c tio n s of v isu a l images to eutaaeouely learned p a tte rn s , hut a v is u a lly learned p a tte rn did aid m a terially in cutaneous reco g n itio n . from th e stu d ie s of Jacobson (a ? ), Shaw (41) and o th e rs m have vary w all e stab lish ed evidence th a t imaging a c tiv ity i s r e a lly im p lic it meter n a tiv ity .

Pros t h i s stand­

p o in t even th e so -called v isu a l iaage i s r e a lly the im p lic it muscle n a tiv ity asso ciated with seeing; the motor Image i s muscle a c tiv ity asso ciated w ith th e response in question. I f th is can be applied to the learn in g ta sk , we may be forced to consider the development o f an im p lic it response coordination.

That tensions do play an Important ro le In

lemming has been shewn by an imposing l i s t o f in v e stig a ­ tions* Cook fu rth e r d istinguished the two p o ssib le trends on the p a r t o f th e su b ject on the b a sis o f th e ir d iffe re n t wad products.

A ttention to stim u li points to Improvement

in accuracy, w hile th e second trend i s toward speed.

Speed

83.

and. accuracy fa»ve » functional re la tio n sh ip ! and such an in tim ate re la tio n s h ip th a t th e re l a no p re c ise d is tin c tio n between them fo r eany tasks*

Set they remain th e o re tic a lly

d istin g u ish a b le a c t i v i t i e s .

In a previous study the w rite r

(18) baa shown in d ic a tio n s o f a d ifferen c e In bodily tea* sie n a l p& ttem e where th a t d iffe re n c e la asso ciated w ith the s u b je c t's a tte n tio n to accuracy fo r the one p a tte rn , and b is a tte n tio n to speed fo r the o th e r. Onoe again the analogy w ith retention time stu d ie s I s p e rtla e n t.

A sensory s e t may very lik e ly be im p lic it mus­

c u la r ten sio n s not involved In the required response b at found around the re c e p to r organ, or favoring i t s function. Freeman (38) has shown th a t th ere i s a g re a te r *spread* o f neuromuscular tension fo r sensory as opposed to motor s e t. A motor s e t may very lik e ly be a

heightened

tension in

those muscles whloh were required in the response.

The

l a t t e r has been extensively studied by Oavls (21) who sug­ g e s ts from h ie r e s u lts th a t the s e t and the response a re not q u a lita tiv e ly d if f e r e n t, but are ste p s in a continuous im p lic it-to -o v e rt process.

He

also fin d s th a t 'te n s io n i s

higher and reao tlo n time sh o rte r w ith a re g u la r than w ith an ir r e g u la r fore p erio d ", in d ic a tin g fu rth e r the ro le o f ten sio n s. S o lleetln g these widely scattered sources o f in f o r ­ mation and suggestion gives eome b a sis fo r the hypothesis th a t there la an e s s e n tia l d ifferen c e in th e muscle ten sio n

m

pattern involved 1m the learning of d ifferen t sort® of tasks* and furthermore th a t the preponderance of task® previously used being weigfeted by perceptual factor# 1® responsible fo r the tpe&ds In the Intarpratatlon® of b ila te ra l transfer*

It

the## ttnelonal pattern# ©an be shown to have some p®mm~ ©no© and p re d ic ta b ility , then m nay have sow very obJe$~

%lm basis for reinterpreting the theories of b ila te ra l tran sfer#

k$ a working hypotheil a I t 1# therefore suggested that tofision&l ant response pattern# related to the &mm organ Involved.(or fa c ilita tin g it# us©}* plus tension© ©oft responses associated with verbalisation* may be said to be rt^ponslble for the tran sfer of perceptual tanks*

Thee©

things are the iden tical elements* sine© they are mmmon to the practised and the transferred series#

these factors

should be wholly or predominantly responsible for tra n sfe r wtem the response is not &•***&©$ q u alitativ ely d ifferen t from an old response pattern*

the only other theory of

tran sfer necessary is one of im plicit p ra o tlo a ^ to account for the tran sfer of the motor factor#

Where the response

is d ifferen t from an old response pattern i t must be shown how that motor coordination is established in the traas** f erred member* so the hypothesis i s advanced th at such, loam* lag i s transferred by virtue of im plicit (or sympathetic) tensions during the practice tria ls* I t is well beyond th© scape of a single experimental

53

in v e stig a tio n to attem pt a cheek upon a l l asp ects o f a pm h tm a* bread as the hypothesis suggests.

The p resen t

proMem w ill th e re fo re b t confined to a very small p a rt o f i t , namely the re la tio n s h ip between the amount of tr a n s fe r In a motor ta sk and the le v e l o f th e muscular n a tiv ity in t^ie to tM fe rre d limb*

I f such a re la tio n sh ip be consis­

te n tly and re lia b ly found* even the most conservative in­ te rp re ta tio n must recognise th a t those In v e stig a to rs who have minimised the Importance of opposite limb a c tiv ity have overlooked a promising lead toward the avoidance o f « muddle o f tra n s fe r theory*

M mrntm n t m m tm m m f In an attem pt to answer a question concerning th e re la tio n s h ip between performance and muscular ten sio n s, one could co n tro l e ith e r one o f these two fa c to rs and measure th e remaining one as the dependent variable*

Thu© in th e

work on tensions and learning pioneered by Bill© (to), ten ­ sion© were under th e co n tro l of the experimenter and th e le arn in g was measured as a function of it*

In a former

study by the present w rite r and previously c ite d (page 51) the te n sio n s m m measured as the Independent variable* The two methods are complementary and valuable as checks upon each, other*

In th e present study tensions were both con-*

tr o lle d and measured as the independent v a ria b le . 4* The Apparatus ft^a

Task* In the se le c tio n o f the ta sk fo r the

su b je c tf c e rta in co n sid eratio n s, tooth p r a c tic a l and th e o re t­ i c a l , had to toe met*

In agreement with the suggestion© made

toy M llisen and Van Elper (Sto) and o th e rs, i t was f e l t th a t the task should toe as nearly a motor ta sk as possible* That i s , I t should emphasise the fa c t th a t learn in g may c o n sist in changes In f a c i l i t y o f a c e rta in muscle group*

F urther­

more, sim p licity as a c h a ra c te ris tic seemed d e sira b le , tooth

as to s u b je c t's d u tie s and the nature of the apparatus* Since th e asso ciated tensions were to be measured by the no­ tio n p o te n tia l technique ( to be d escrib ed ), no e l e c tr ic a l devise would be employed* since I t would produce I n te r f e r ­ ence masking the myograms*

Another lim ita tio n imposed by

the e le c tr ic a l measurement technique i s shown by the fa c t th a t i t has an extremely small range In terms o f the bodily area to which i t i s applied*

Davie (£2) has pointed out

th a t w hile we may be able to obtain no s ig n ific a n t tension* a l changes in one area we are not warranted in saying th a t such changes do not exist* fo r they may e x is t in a d iffe re n t are a , and possibly only a few Inches away from the electro d e placement we have chosen*

fo r th a t reason* I t was obviously

d e sira b le to choose a task which could be and would lik e ly be executed by a r e la tiv e ly small muscle group*

Such a

procedure* while not guaranteeing a c r i t i c a l placement o f th e electrodes* does appreciably in crease the p ro b a b ility o f it*

For example* a ta sk which could be performed by the

subject w ith e ith e r w rist* elbow* or shoulder motion would present a problem in measurement o f tensions o f consider­ able more d if f ic u lty than on© which could be performed only by the w rist* In order to b est meet a l l o f these requirements* a modified pursultm eter was constructed a® shown in the d ia ­ gram in fig u re 1* th e instrum ent exposed to the subject a moving waxed Stylograph tape* th ree inches wide, upon the

56

surface of which a fiv e mm. wide pathway was marked#

This

pathway followed a sine wave pattern# with a complete cycle having a *waw© le n g th *1 o f a b/18 inches*

The p a tte rn was

dram, on the tape beforehand, from a master s te n c il mad® fo r the purpose. The expo sure device was a kymograph open the drum o f which th e tape was wound; and supplied from a r o l l o f the tape attached to one aide#

The r a te of the kymograph was

such th a t the tap© wee presented a t a speed of' one cycle of the nine wave pathway ©very ten seconds# or 13 ? /8 inch©® per minute*

The kymograph was a good q u a lity , spring driven

instrum ent constructed by Charles Verdin, Paris#

Under th e

condition® i t was used# being rewound every seven minute® o f operating time# th e speed o f exposure was measured as con­ s ta n t w ithin

& tambour and le v e r arrangement was a t-

Cached to the frame o f the machine In such a manner th a t the p o in te r of the le v e r was impressed ag ain st the waxed paper tape with s u ffic ie n t firmness to trac e I t s pathway#

atop®

were adjusted on th e le v e r Ju st f a r enough a p a rt to give a range o f motion beyond the amplitude o f the sine wav© path­ way# but short of th e lim its of the tape#

A rubber ho©© a t­

tached to the tambour a t on® end and to a sm all rubber bulb a t th e o th e r completed a closed pneumatic system by which the subject could co n tro l the a ctio n of the lever#

The ta sk ,

o f course# was to keep the p o in ter w ithin the pathway* accompanying fig u re s fu rth e r explain th is apparatus#

The

57

FIGURE

I . DIAGRAM OF LEARNING DEVICE

KYMOGRAPH v FRAME \

KYMOGRAPH

DRUM

5TO P ROLL

OF

STYLOGRAPH TAPE ROBBER HOSE

5 P R IN Q

5PR1NG MOTOR HOUSING

APPROX. s u b j e c t 's

BULB

S IZ E

W IN DING

HANDLE

SUBJECTS

VIEW

FIGURE a. SAMPLES OF LEARNING RECORD

TRIAL LI

TRIAL RI

TRIAL RIO

TRIAL L4

TYPICAL RECORD OF A SINGLE SUBJECT. EACH SAMPLE IS ABOUT % OF A T R IA L . APPROX . SIZE.

%

88

She Measurement o f Im H aB *.

Although the muscle contrac­

tio n s accompanying th e a c tu a l manipulation o f th e le a rn in g ta sk may be e a s ily observed and n t a measured to a c e rta in degree o f accuracy with tambours o r o th er e ld e r modes o f measurement, no such device would be o f any use in d etectin g th e tenaione in th e *iu»n*ueed* member.

Dunlap in 1932 (28)

euggeeted the use o f a se n sitiv e galvanometer fo r such p u r­ poses*

At th a t tin e th e actio n p o te n tia l technique bad not

been applied to learn in g problems*

The apparatus used f o r

measurement o f th e e le c tr ic a l m anifestations o f muscular tension (myograms) in the present study has been prev io u sly described by Daniel (18) and e a r l ie r by Davis (28). A ty p ic a l a c tio n p o te n tia l technique c o n sists of fouur u n its! electro d es in contact w ith the su b ject, an a m p lifie r to provide a high degree of gain o f the e l e c tr ic a l d isch arg e, a galvanometer o r oscilloscope to change th e e le c tr ic a l energy in to lig h t energy, and fin a lly a camera o r o th e r de­ v ice fo r mating permanent records o f the changes.

The p a r­

tic u la r equipment used fo r the present study consisted of two such systems, Independent of each o th e r, and operating sim ultaneously! mating p o ssib le th e recording of ten sio n s from two body lo c a tio n s a t the same time. She surface type of electro d es used were round m etal d is c s , fiv e mm. in diam eter, and fastened a t th e cen ter of a ba& ellte d isc 1 1/4 inches in diam eter.

A moist co n tact

between the s u b je c t's akin and the activ e electro d es was

m made p o ssib le liar th e use o f Sanborn *ftedux* eleotrode pact©, eommoJily used In electrocardiograph work*

A f e l t pad (3 %

e X i /2 inches) soaked in sa l in© so lu tio n v a t placed between the skin and th e n e u tra l electrode* which wae eomon to the two am plification systems* head* from the electro d es wore fed in to the 3 stage hlgh-gain* re sista n c e coupled a m p lifie rs e sp e c ia lly con­ stru c te d fo r a c tio n -p o te n tia l work*

the e le c tr ic a l design

o f these has been described in g re a te r d e ta il by Carlo [%Z)* and need not be repeated here*

A fter passing through th e se

units# the p o te n tia ls were fed Into the cathode ray o s e il loscopes where they were fu rth e r am plified and then Im­ pressed upon the v e r tic a l d e fle c tio n p la te s of the cathode ray tube*

the p o te n tia ls could then be observed as ra p id

h o riz o n ta l d e fle c tio n s o f a spot of lig h t upon the flu o re s­ cent screen forming the end ©f the tube*

One o f the two

systems made use o f a Olough Breagle* model CHB* th ree -in ch oscilloscopes the o th er an Allen a , OuUont, type 158* equipped with a fiv e -in c h tube*

Both o f these Instrum ent0 had tubes

with a flu o rescen t m aterial giving a blue, ra th e r than th e customary green, lig h ts since the blue I s more re a d ily photographed* A high speed General Hadl© moving film camera using 35 mm# s e n sitiz e d paper was used fo r photographing the two o scillo sco p es simultaneously#

th e la rg e r f ie ld was by d i­

r e c t focus* the sm aller was by means of a m irror placed a t

60

a 46 degree angle and aligned with the two instrum ent a* th e usual equipment fo r developing, fix in g , and drying the film record was provided# A dditional equipment used in the p resen t study 1**eluded a small mm tube enclosed in a c a rtrid g e and placed w ithin the range o f the camera#

The tube was a c tiv a te d by

a 60 cycle commercial current In s e rie s with 90 v o lte o f d ir e c t cu rren t (two ttB* b a tte rie s ) which caused p erio d ic fla sh e s o f one of the two p la te s la the tube#

Forming the

th ird xaarfc on the photograph record* th is provided a refer** enow lin e in 60the o f a second. C alib ratio n o f the systems was made by s u b s titu tin g the output of a Clough Brengle (model 790} vacuum tube osd i l a t o r fed through a General Hadio M icrovolt or (type 646-6) fo r the leads from the su b ject4®, electrodes#

Various sen si­

t i v i t i e s wart used, as explained in a l a t e r section# The e n tire system i s completely metal shielded through­ out ag ain st in te rfe re n c e and eddy currents#

A booth fo r the

subject in one corner of the laboratory has w alls. H o ar and c e llin g of screen w ire, and the electro d e lead s pass through the w all w ithin e le c tr ic a l conduits Into the next room where the remainder of the equipment i s located*

A schematic d i­

agram of the arrangement i s shown in fig u re 3. B* The Procedure sab.tflO.ULa la n k .

From the d escrip tio n of the s u b je c t's ap-

FIGURE

3. DIAGRAM

OF

APPARATUS

ARRANGEMENT

AND

WIRING

PLAN.

61

62

p aratu s i t Is evident th a t the task consisted of a lte rn a te p ressu res and re la x a tio n s upon the rubber bulb which wag held between the fin g e rs and the palm of the hand.

In

e a rly t r i a l s these movements would be e r r a ti c , uneven and In some cases, breaking down entirely*

In l a t e r t r i a l s

they would be smooth, even and rhythm ical as evidenced by t h e i r agreement w ith the pathway Its e lf#

A good comparison

I s made in the diagram o f fig u re 2# I t m y be said th a t the le a rn in g o f th i s task c o n sists o f the progressive ac* qui& ition o f p recisio n in a lte rn a te ly flexing and extending the fingers* th e subject was brought Into the booth, seated and attached to the apparatus, then allowed (o r persuaded) to relax, fo r a period o f 3 to 6 minutes*

During th is tim e, an

a ctio n p o te n tia l record (to be described) was made, to serve as a referen ce le v e l o f activ ity #

Immediately afterw ard the

experimenter gave the subject the following verbal In s tru c t tlo n s , dem onstrating the task as the In stru c tio n s were givens lo u r task Is to keep the p o in ter w ithin the pathway formed by the wavy line# n o tice th a t when I squeeze the bulb, the p o in ter goes up, and when I rele ase the bulb, the p o in te r comes down* lou shoul&nH expect to be as good as I am, because X*ve prac­ tic e d a g reat deal—but you can get p re tty good in k few t r i a l s of practice# Do you see how i t works? Bow I think you w ill fin d I t b e tte r to ad ju st th e bulb to i t s most comfortable p o sitio n in your hand before you s t a r t , then keep th a t same p o sitio n throughout* [Subject does so^ The a s s is ­ ta n t w ill s t a r t and stop the machine. He

m

w ill t e l l you when to get ready to s t a r t , when to stop and which M ad to use. When you are not working I want you to completely re la x your g rip on the bulb, so th a t you w on't t i r e so easily* Sow are you ready to begin? Although the subject was allowed to observe the exp e r c e n t e r operate th e machine fo r a few cycles he m&

o f th e p ath ,

not allowed to press the bulb during any timeth a t

the machine was moving u n ti l the experiment was a c tu a lly be­ gun*

th e a s s is ta n t s a t in the cage with th e su b ject, d ir e c t­

ing th e a c tiv ity and timing the t r i a l s with a stop watch# Subject was allowed SO seconds of work followed by 30 sec­ onds o f r e s t .

At the ra te o f p re se n ta tio n , t h i s meant a

m atter o f three complete flexion® and extension® o f the fin ­ g e r p er tr ia l*

On each t r i a l s u ffic ie n t time was allowed

before tim ing began to enable the kymograph to reach peak •peed and to allow the subject to get the re s tin g p o in ter in to the pathway. fh® subject was given two t r i a l s with th e l e f t hand, ten t r i a l s with the r ig h t, and fin a lly two t r i a l s with th e l e f t hand*

Thus th ere were two l e f t p re -p ra c tic e t r i a l s ,

ten r ig h t p ra c tic e t r i a l s , and two l e f t p o st-p ra c tic e tr ia ls # The tra n s fe r was th e re fo re from rig h t to l e f t , the rig h t be­ ing the p racticed member and the l e f t the tra n s fe rre d member. The su b ject was not in stru c te d concerning th e p a tte rn of the t r i a l s j h® did know th a t both hands would be used a t some time*

Mmy of the subjects reported th a t they did not ex­

p ect to re tu rn to the use of the l e f t hand.

Following the

64

SMp3U&t4m'0f th© p o s t-p ra c tic e s e r ie s , the subject w e in ­ s tru c te d th a t the experiment was over sad asked to re la x fo r a few laonente*

during th is time another so tio n p o te n tia l

record of r e s t was made#

iu b je e t# were not holding th e bulb

during th e se r e s t periods# th e task wee s u ffic ie n tly unique and in tr in g ie e lly in te r e s tin g to preclude the need fo r m otivation o th er than th a t provided by the I n i t i a l demonstrated performance o f the

ho subject reported fa tig u e nor showed

say observable signs o f it* demands o f the task*

Stone fa ile d to understand the

One subject (fem ale, age 23) was ob­

v iously hoped, but her record m s included since i t showed no apparent v a ria tio n from others* al. MStMM*

Th% s e a l i n g method of measuring

n o tio n p o te n tia l# was followed, since a complete p ic tu re o f tetM&ea during 14 whole t r i a l s would have been p ro h ib itiv e both a t to time and m aterial involved*

in ad d itio n , wueh a

procedure would n e c e s s ita te stopping the experiment and re ­ loading the camera,

th e i n i t i a l and fin a l r e s t records

have already been mentioned*

In addition to these, records

were taken, during each o f fee 14 t r i a l s 5 ©ash sample being a few second# In duration and occurring very near to the end o f th e f i r s t ten seconds of work#

Measurements were

mad# from an electro d e placement on the v o lar surface of each forearm above the fle x o r muscles of the fin g e rs.

86

S his procedure gave 13 record ample e pep ebbjeet fop each ora from which th® measurements were mode accord­ ing t© ft technique to be described.

Before any measurements

eobM be meaningful, the o v e ra ll s e n s itiv ity o f th e appara­ tu s had to be determ ined,

t h i s e a llb ra tlo n m e made d a lly

during th e period ebon subjects were being tooted* and m o deae in th e following Banner.

The o a o illa to r «ae s e t a t a

frequency o f 100 eyelee per second and fed in to the mlerov o lte r v h e r e th e energy le v e l oould be c o n tro lle d and ac­ c u ra te ly aeaooped.

th e output o f th e sd e ro v e lte r m e at*

inched to the a m p lifie rs in th e sane manner •« were the sub­ je c t* # le a d s during operation.

A m plifier gain oontrols were

than fltt a t th e low est le v e l whieh had been used during th e experim ental sessio n s, and a recording m s made w ith th e cement o f th e re s u ltin g d e fle c tio n on the o scillo g rap h screen* ft n o ta tio n o f th e reading o f the a ie r o v e lte r was the only o th e r Inform ation needed to compute the c a lib ra tio n ,

th u s ,

a t 100 ey elee, an input o f $ m icrovolts w ill equal a d efle c­ tio n o f j m . (o r e th e r measure) on the film when the a a p liH e r gain controls a re s e t a t j end £•

Such measurements

ware mad# fo r every gain co n tro l se ttin g used since th e p re­ ceding c a lib ra tio n in every ease.

Although li n e flu ctu a­

tio n s , b a tte ry drainage, tem perature and o th er v a ria b le s provoked a c e rta in amount of v a r ia b ility in s e n s itiv ity , a good degree o f constancy was in d icated by th e c a lib ra tio n figures*

However, individual su b ject records were adjusted

86

according to th® c a lib ra tio n made on the sane day the (sub­ je c t was te s te d . t h i s method o f c a lib ra tio n gives an in d ic a tio n o f th e o v e ra ll s e n s itiv ity o f the system, including am plifies* Won g a la , cathode screen d e fle c tio n , and camera le n s reduc­ tion*

Since a l l o f th e fa e te rs h erein included are const suit

throughout any experiment, except th e gain o f the a m p lifie rs, th e c a lib ra tio n values are expressed in term s o f th is g ain , th e la titu d e o f gain in any study shore both o v ert and im­ p l i c i t muscular a c tiv ity are being measured must be very g r e a t, elnoe th e former may be as much as 100 tim es as la rg e as tin® l a t t e r .

In th® present study the' range o f s e n s itiv ­

i t y was from .50 m icrovolts input per 50th o f an inch r e ­ corded d e fle c tio n to S3.68 m icrovolts p e r 60th of an inoh fo r th e one am p lificatio n system.

I t varied between ,31 mi­

c ro v o lts end 83.07 m icrovolts fo r the o th e r system.

In gen­

e r a l, th e higher s e n s itiv itie s were used fo r measuring the a c tiv ity of the hand which was r e s tin g , and th e lower sen si­ t i v i t i e s fo r measuring the a c tiv ity of the worhlng hand. Once the c a lib ra tio n fig u re was determined fo r any given am p lificatio n s e ttin g , i t could be used as a constant by which to m ultiply th e d ire c t measurements of the records made in BOthe o f an lech.

The r e s u lt i s an ex cellen t in d i­

catio n o f th e energy le v e l of the muscle a t th e moment o f sewp iln g ,

fo r the present study, three .1 second periods

w ere selected a t random from each arm myogram on each o f the

6* recorded M aples.

From every .1 second p erio d , the th re e

la rg e s t d e fle c tio n s were measured In gothe o f an in to , sad an average o f the re s u ltin g nine measure• «»• as&e*

This

average i s the fig u re which may he a a ltip lie d by the appro* p r i s t s am p lificatio n constant to obtain the le v e l of o u sels energy output*

For sash of th e 46 subjects used in to e

study th e re a re measurements from toe two arms} 16 reoorded samples frost sash; 6 periods from e&oh recorded sample) 3 d e fle c tio n measurements from each period*

By computation

o f th ese fig u re s (46 * 2 * 16 x 3 x 3) i t i s seen th a t about 13,210 &1a e ra te measurements oosiprise toe d ata. Esperlm eptal Sfonfeols.

Subjects used were summer s to o d

stu d en ts a t Indiana University*

Their sex d is trib u tio n s

and mean ages a re shown in th e summary ta b le on page ? i A ll su b jects were r ig h t banded.

They were divided a t random

In to to rs e groups in order to o b tain to res d iffe re n t le v e ls o f a c tiv ity on the p a rt o f to e tra n sfe rre d member,

i l l sub­

je c t a followed toe plan of toe experiment already described) they d iffe re d only in toe nature of toe a c tiv ity o f toe l e f t hand t o i l s to e rig h t hand p racticed . Group A was c a lle d "normal tra n s fe r1'.

They were a l­

lowed complete freedom o f the l e f t hand during rig h t work. Their a tte n tio n was not d irec ted to th i s unused hand, nor d id they know o f the conditions o f toe other groups.

Any

normal a c tiv ity of to e l e f t hand was allowed, except, o f

aa

co u rse, aiding th e r ig h t hand to perform th e teak* Group 8 m e c a lle d " f a c ilita te d tr a n s fe r" .

During

p ra c tic e by the r ig h t hand, su b je c ts in t h i s group operated a dummy bulb in th e l e f t hand in a synehronoue re la tio n s h ip to th e operation o f th e rig h t bulb,

a t the beginning o f

th e te n rig h t p ra c tic e t r i a l s , th e a s s is ta n t In terru p ted ttte proeedure long enough to in a tru o t th e su b ject to aqueese both bulbs a t the sane tim e, and as nearly a lik e as possible* th e re sag no hose attach ed to the dunny bulb in th e l e f t hand, so the su b ject was ira ll aware th a t h is performance was a fu n ctio n o f M e r ig h t hand.

I t i s not known how w ell th e

su b je c t followed th e in s tru c tio n s regarding th e l e f t hand b u lb , M use no record was made,

th e action p o te n tia l rec­

ords do show th a t th e le v e l o f a c tiv ity m i markedly in* creased, sad they show how much i t was increased,

i b i s meth­

od o f inducing tension i s considerably (superior to many o th e rs previously employed, sin es i t does not in te r f e r e w ith th e ta sk , e ith e r mechanically o r psychologically. two stu d ie s in the l i t e r a t u r e fu rn ish somewhat con­ tra d ic to ry suggestions as to th e r e s u lts to be expected when th e two bands are perforating th e task sim ultaneously. A lttough Beefy (3) was studying whole v s. p a rt motor le a rn ­ in g , he in c id e n ta lly observed the seme amount o f tra n s f e r from two hand p ra c tic e as from opposite hand practice*

th e

ta sk was a sty lu s tra c in g of a square p a tte rn and the re ­ m i t s j u s t i f y th e conclusion th a t th is s o rt of tra n s fe r " i s

es

g en eral ra th e r than sp e c ific In nature*, according to Beehy* M#rc&we&e (§4) has negative evidence In d ica tin g the posai** t d l itj r o f p o sitiv e e ffe c ts o f simultaneous- p ra c tic e ,

then

the two hands practised at the same time but in opposite directions# there wee ifitagfaysfliia of subsequent one hand activity*

neither of these studies i s d i r e c t l y eoaqpar&ble#

however. 0roup 0 was c a lle d ^ in h ib ited tran sfer* * In a pro* views ua^ublisbed study where conditions were almost id e n ti­ c a l to those h erein described, a method had been found which reduced tension to a marked extent without producing d is tr a c ­ tio n or o th e r interference*

i t co n state of wrapping th e

l e f t forearm area w ith the p ressure cu ff o f a sphygpmexiO"*

mtm* in f la te d to a pressure o f about SO sum# This i s not s u ffic ie n t pressure to In te rfe re w ith circulation#, yet i t seemed to force a re la x a tio n in s p it# of the rig h t hand ac­ tiv ity .

fig u re 4 shows the amount o f tension in the l e f t

arm o f a group o f 10 su b jects wearing th e c u ff ( "in h ib ited tr a n s f e r 41) as compared with a group where th e hand i s fre e (*nom al transfer*)* Tioixs study*

The d ata (fa b le 1) are from the pro**

f o r some reason not q u ite clear# tension was

not e ffe c tiv e ly reduced In the ten rig h t p ra c tic e t r i a l s during which time i t was used on th e l e f t mm o f the p re s­ ent group o f subjects* an page 98.

A p o ssib le explanation is discussed

70

Table I* lev el of tension for lo ft band showing th® effect of the tension reducing control*

Group

jfSOo

ln lt( Host HI

Final

Successive tria ls ~ Practice series

2

3 '4

5

6

7

$

9

10 Host

10 32*9 32.2 as*4 28,0 29.0 31.1 31.7 31.2 29.9 32.8 26*2 14*5 137 133 116 116 124 128 133 128 124 137 108 63 Inhibited 12 25*7 22.4 14.9 17.4 14.0 21,8 18.7 15.7 14.0 25.3 23.1 11.6 137 iao 78 m 73 115 99 84 84 131 120 63 Bengal

Bppar number for m$k tr ia l Is la mean microvolts* loner number Is tbs corresponding % of mean rest microvolts*

figure 4* Tension la m&mmicrovolts for normal and inhibited groups.

* m m M r m m

m m m m

5u

m

at M r §4 10

Init* HI Best

3 4 5 6 ? a 9 Successive trials * Practice series

a?

10 Final

Rest

71

A quick summary o f the su b jects and procedure ie a f­ forded by the follow ing ta b le t fa b le i»

f la n o f th e experiment A, ^normal

tra n sfe r*

Transfer* f

i

female

0

4

9

to ta l

U

15

16

Mean age

£4*1 £ £*»

£4*5 £ 2*V

84*5 £ 2 * &

Mi% hand

£ tria ls

Z t r ia ls

£ tria ls

10 t r i a l s l e f t hand fre e

10 t r i a l s l e f t hand working

10 t r i a l s l e f t hand • r e in e d *

a tria ls

a tria ls

2 tria l*

hand

ii

QO*

a*•in h ib ite d

ms/is n

H

aaoupa b# ^ F a c ilita te d tr a n s f e r 11

L eft hand

#Probable error* 0* th e Experimental Data a f c lM te l ia m A m MSOXM*

Various treatm ents oould be a s-

corded to the o b je c tiv e performance o f the su b ject,

Follow­

ing the usual procedure with such a task* th e data were m m m ** tired in term* o f e rro rs . ©Idea o f th e pathway

mm

Each tin e the p o in te r touched the counted

m

m

e rro r.

If

the p o in te r

l e f t the path com pletely# then returned* the r e s u lt was two error**

I t 1# p o ssib le with th is treatm ent fo r a subject to

92

•ride* th e boundary lists of the pathway md receiv e the pen­ a l ty o f only one error#

th i s i s a serious problem when th e

p ath i t s e l f l a s ta tio n a ry , but caused m c©m®m h ere, where the path Is moving, making' i t J u s t as d i f f i c u l t to *ride the Xiao** as to stay w ithin the pathway#

The number o f e rro rs

p er t r i a l was e sta b lish e d a r b i t r a r i l y as the number of e rw s fo r the three complete cy cles of the pathway follow ing the p o in t a t which th e subJcot1g marker f i r s t came Into th e pathway*

th e t r i a l s were s u ff ic ie n tly long to prowids

s lig h tly more than the th ree c y c le s, to allow fo r the v a r iable a t th e i n i t i a l p a rt o f the trial,*

A b e t te r m derstand*

ing o f the raw learn in g record may be had by re fe rrin g to the diagram on page ffip* T ablet &, 4, and 0, on the following pages, present the in d iv id u al subjects* learning d ata in terms o f errors# The t r i a l by t r i a l averages give the d ata from which the em­ p ir i c a l average le a rn in g curve i s drawn* smoothed curve w e also shown.

th e values fo r the

These values are derived by

f i t t i n g th e raw d ata to the function t mA ** sc hog X, by th e method o f le a s t squares#

I i s the value (e rro rs ) to be ob­

tained! X i s the value o f the t r i a l number} A and K are- unt e w s which are obtained by sim ultaneously solving the two n o rm ! equations fo r the function*

These equations arai

(I) £X * SA • K(£ Log X), and (XX) £(X Log X)

m

A(£ Log X)

-

X£(Los X)2

I t oast be seen th a t the equations are derived by m ultiplying

75

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