TOWARD A SCIENCE OF NEUROPSYCHOLOGY - Karl Pribramkarlpribram.com/wp-content/uploads/pdf/theory/T-002.pdf · 2014. 11. 2. · TOWARD A SCIENCE OF NEUROPSYCHOLOGY (Method and Data)

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TOWARD A SCIENCE OF

NEUROPSYCHOLOGY

(Method and Data)

KARL H. PRIBRAM

DR. PATrON asked me to discuss with you the relation­ship between neurophysiology and psychology.

'Vith the increasing popularity of the "interdiscipli­nary approach" ther~ would be no apologia necessaryfor a science of neuropsychology were it not for the badrepute into which this area of investigation has fallen.Such well-deserved infamy stems, in part, from thedualism which has plagued all of the behavioralsciences during the past 50 years and, in part, hom theexcessive "psychologizing" of physiologists and "phys­iologizing" of psychologists which fills our journals andmonographs. The first figure serves to illustrate the re­sults of such schizoid endeavors.

The deficiencies of the conceptualizations diagramedhere become obvious once they have been pointed out.What psychophysicist would assign. the same numeralto different classes or assign different numerals to thesame class? Yet, flagrant disregard of this simple rule ofthe most elementary of scaling techniques pervadespractically every cytoarchitectonic study and is shownat its worst in Figure 1. \Vhat biologist would, in hisown field, classify together such diverse categories asocular adversive movements, optic awareness, visionintensity, color recognition, place memory, construc­tive thinking, and constructive action, without some

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toCALIZATlON OF THE FUNCTIONS OF THE CEREBRAL COR.!EXON ANATOMIC UNES. OUTER... SURFACE

From Kleist. K. Kriegsverlelzungen des Gehlrns. p. 13M.

FIGURE I. "Localization of function" in the human brain accordingto a recent authority. See text for "what's wTong·' with this figure.

referent of internal consistency and some attempt atordinal ranking? Finally, where is there available adiscussion of the reliability and the validity of thetechniques used to construct this monstrosity? Thevast differences between various textbook diagramsand the differences between these and our clinical ex­perience suggest the answer to this question.

But what of the experimental studies which havedealt with the relation of brain and behavior? Manysuch studies using behavioral measures have manip­ulated environmental conditions and inferred brainfunction. Other studies have manipulated the centralnervous system and measured electrical, histological,

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KARL H. PRIBRAM

or physiological (e.g., movement, blood pressure) re­sponses and inferred a relationship to behavior. Suchinferences appear to suffer from the paucity of dataaccumulated thus far. Some studies have manipulatedthe brain and rneasure,d behavior; these often sufferfrom the limited applicability of the specific findings.In an attempt to overcome these difficulties, the typeof study reported here was undertaken: In these ex­periments both the central nervous system and envi­ronmental conditions were manipulated and the inter­action of these manipulations with the behavior of theorganism has been measured.

Since this approach is still in its infancy, data ratherthan laws will be presented. The data describe the re­lationships between the manipulations performed (in­dependent variables) and behavior (the dependentvariable); it seems premature to attempt systematiza­tion of the interrelationships of these independent anddependent variables and thus to formulate laws or con­cepts. When such la:ws are formulated, they will, ofnecessity, be within the framework of a behavioristicpsychology. The problem of relating such·scientificlaws to "private experience" (or Gestaltists· "phenom­ena") isa problem which behavioristic psychologysnares with other sciences and lies beyond the scope ofthis conference.

Since this approach considers the biology of the or­ganism as one of several classes of independent var­iables determining behavior, a necessary first steptoward a science of neuropsychology (by definition, areductive science) is a description of the central nerv­ous system in terms other than those defining relation-

TOWARD A SCIENCE OF NEUROPSYCHOLOGY

ships to the dependent variable (behavior) used in theneuropsychological experiments. Such description isthe task of neuroanatomy and classical neurophysiol­ogy. For this occasion, I have chosen a description basedon thalamocortical anatomy, though one based on cy­toarchitecture, "evoked potential" studies, strychnine"neuronography," or a combination of these mighthave served as well.

Thalamocortical systems may be classified accordingto whether the thalamic component receives its majorafferents from within or from outside the thalamus.The term "intrinsic" has been applied by Rose and"\VoolseylT to those thalamic nuclei which do not re­ceive their major afferents from outside the thalamus.Thalamocortical systems receiving extrathalamic affer­ents are of two types: those receiving spinal and mes­encephalic afEerents, and those receiving diencephalicfibers. The former (often called tl}e "primary projec­tion systems") are hereinafter called "extrinsic," fol­lowing Rose and \Voolsey; the latter are most usefullyconsidered under the heading"rhinencephalic."ll Twoexamples of current investigation of the intrinsic sys­tems and one example of those of the rhinencephalicsystems will be presented.

Figure 2 presents the surgical manipulations of theneural variable in these experiments. Represented arethe reconstructions of the cerebral hemispheres of 40monkeys. The lesions were made, in most instances, onthe basis of criteria other than those defining the thal­amocortical relationship, a consideration which neednot enter this presentation. All diagrams are made bytransferring to standard brain outlines the actual

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KARL H. PRIBRAM

FICURE 2. Schematic representation of locus and extent of resectionsperformed in 40 monkeys used to relate specific neural S)"stems to .specific behavioral processes. (The original. reconstructions of thebrains of these animals appear in References 5. 6, 8, 9. 10, 14.)

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

reconstructions from serial sections of the lesionedhemispheres.

In order to decide upon a relevant dependent vari-

SIMULTANEOUS VISUAL CHOICE REACTION

OPERATES WITHOUT DmCIT OrERATES Wmt DEFICITPre Post Pre Post

OPI 200 0 PTOI 120 272OPI 220 0 PTOI 325 FOP3 380 0 PT03 180 F

~LT I 3go 19o PT04 120 450LTI !loo 150 Tl 94° FHI 110 220 TI 330 FHA 35° 240 VTHI !l20 F

IT I 580 50 VTHt 370 F

IT3 50 0 VTH3 280 F

IT4 2°5 0 VTH4 440 FITS 300 100 VTI 24° FIT6 ISO 100 VT2 200 FDLI 160 14° VT!I 200 8goDLI 540 150 VT4 410 FDL3 !loo 240 VT5 210 FDL4 120 100MVI 110 0MV2 150 10 NON-OPERATE CONTROLS1\1V 3 2go 130 CI 7go 80\'.IV 4 230 10 C2 23° 20MV5 280 120 C3 750 20CIN 1 120 80 C4 440 0CIN2 400 60C1N3 115 74CIN 4 240 140

FICUllE 3- Pre- and postoperative scores on a simultaneous visualchoice reaclion of the animals whose brains are diagramed in Figure lZ

indicating the number of trials taken to reach a criterion of go per centon 100 consecutive trials. Deficit is defined as a larger number of trialstaken- in the "retention" test than in original learning. (The mis-placement of the score H I does not change the over-all results asgiven in the text and in the following figures.)

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KARL H. PRIBRAM

12 FfZ72-Fl

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SIMULTANEOUS VISUAL CHOICE REACTlONPlEOP SCORES: 44 ABIIAALS J15 (50-940)

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figure 3. The number of animals per group is indicated below groupname; the range from which median scores are taken appears inparentheses next to the median.

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able, approximately 30 different behaviors were ob­served and quantified. Those behaviors which wereaffected by some lesions and not by others were thenchosen for further investigation. Our first example ofsuch behavior is the visual choice reaction or visual.discrimination task.

Figure 3 gives the individual animal's pre- and post­operative scores in a visual choice reaction in whichpainted patterns were used as cues. Figure 4 summa­rizes these results. Scores were classified into deficitand no-deficit on the basis of whether an animal tooklonger to relearn the task postoperatively than to learn .itpreoperatively. As can be seen, there is no overlap inscores between the group with no-deficit and that withdeficit; in fact, the latter group contains 12 of 15 ani­mals which never relearned the task even though 1,000

trials were given postoperatively (preoperative meanfor learning wcis approximately 375).

Figure 5 groups the lesions of the animals with deficit·and those without deficit. A shows the summed an:a of

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

VISUAL CHOICE RIEAC'U'OOM

FIGURE 5. The upper diagram A represents the sum of the areas ofresection of all of the animals grouped as showing a deficit in Figure 3and Figure 4. The middle diagram B represents the sum of the areasof resection of all of the animals grouped as showing no-deficit inFigure 3 and Figure 4. The lower diagram C represents the intenectof the area shown in black in the upper diagram and that not checker­boarded in the middle diagram. This intersect represents the areainvariably implicated in visual choice behavior in these experiments.

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KARL H. PRIBRAM

all of the lesions which produced deficit; B the sum ofthe area of all of the lesions which failed to produce adeficit in visual discrimination performance. C repre­sents the intersect of the area shown in A with the totalarea not shown (check~rboarded) in B. This may beconsidered an approximate minimal locus implicatedin visual choice behavior in the 40 lesioned animals.This locus approximates that of one of the posteriorintrinsic systems and will be referred to as the "infere­temporal" sector.

Having established a selective relationship betweena lesion in ODe of the intrinsic systems and a restrictedportion of the behavioral spectrum, we proceed to in­vestigate the environmental conditions upon whichthis relationship is dependent. For instance, we havecalled the task a visual choice reaction. Is perfcrmanceof other visual discriminations affected by this lesion?So far, experiments have shown performance of a vari­ety of visual object. color, and brightness discrimina­tions to be altered."II What would happen if in place ofthe visual discriminanda, their logical analogues insomesthesis were substituted? Would the same. or a dif­ferent, cortical area be implicated?

Figure 6 shows the results of an experiment wherethe visual choice reaction was compared with a task inwhich vision was excluded and a solution of the prob­lem depended on handling the cues. Two intrinsicsystems were surgically invaded-the inferotemporaland the occipitoparietal. As can be seen, lesions of theoccipitoparietal sector fail to interfere with visualchoices but affect those based on somethesis, whereas

TOWARD A SCIENCE OF NEUROPSYCHOLOGY

. the lesions involving the inferotemporal sector inter­fered selectively with the visual.s

FURTHER BEHAVIORAL ANALYSISOF THE PTO CORTEX

PolS P..5 P49 TH T45Visu:tl10 (0-70) 0 0 0 (500) (soo)Somatosensory60(0-100) 460 120 350 70 50~ew Somatosensory (1000) (1000) (1000) 320 260

FICl'RE 5. Comparison of retention scores of inferoternporal T andoccipitoparietal P operates on a visual and somesthetic task in whichlogie:tlly an:tlogous cues (+ ,,'S. 0) were used. The mean and range ofthe preoperative retention scores appear under the title of the task.The scores on the "new somatosensory" task indicate original post­operative learning of a length discrimination. Parentheses indicatefailure to reach criterion in the number of trials given."

If it can be stated that the decrement in performanceis restricted to the visual choice reaction, and other ex­periments on taste,l conditioned avoidance,15 and de­layed response!' 8. 9.10. U support this contention, weare faced with a second cerebral "visual" system. Thus,in addition to the extrinsic (geniculo-striate) system,there is at least one intrinsic system which functionsselectively within this modality. It becomes important,therefore, to distinguish between the functions of theextrinsic and intrinsic visual systems. For example, reosections within the former, that is, of the striate cortex,lead to field defects; those of the latter, the infero­temporal cortex, do not. Other studies which specifysuch differences have been completed or are in prog­ress and will be reported elsewhere.8• 19

Today, I wish to limit myself to one other aspect of

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KARL H. PRIBRAM

the relationship of inferotemporal lesions to visualchoice behavior.IlI Figure 7 describes an experiment in

VISUAL CHOICE REACTION. SIMULTANEOUS vs. SUCCESSIVE

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which animals were taught to choose one of two dis­criminanda (an ashtray and a tobacco tin) presentedsimultaneously. The animals were then tested in situa­tions in which these identical cues were presented suc­cessively, and the performance of inferotemporal op­erates was compared with that of control operate andnon-operate control groups. Here.. as in the experi­ments of Riopelle and Ades,lO and of Mishkin,' infero-

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

temporal operates have progressively greater difficultyin a series of tasks graded in "distinctiveness" as meas­ured by the difficulty of the task for the control groups.In this instance, however, "distinctiveness" is not de­pendent on the physical dimensions of the cue, but

CLASSICAL DELAYED REACTION

OPEJlATES WITHOUT DEFICIT OPEJlATES \VITH DEFICITPre Post Pre Post

JPTOI 680 270 DLI 290 FPT04 1020 54° DL2 210 FT2 6jO 120 DL3 590 FVTHI 100 0 DL4 24° FVTH2 60 ° MV2 610 960

VTH3 560 ° MV3 43° 750VTI 290 20VT2 13° 0VT3 740 33° PT03 53° - 630LT 1 14° 0 TI 60 90LT2 14° 0

HI 35° 5°H:\ lio 14°IT3 200 100FT4 300 0

IT5 i50 300FT6 1250 400CI~ 1 820 360CIX 2 600 15° NON-OPEJlATE CoNlltOLSCIX 3 21 5 150 Cl 10 110CI;'I; 4 3-15 ISo C2 590 0~fV I 63° 60 C3 23° 25°~fV 4 590 24° C4 440 330~fV 5 3So 230

FIGl:!l£ 8. Pre- and postoperative scores on delayed reaction ofanimals whose brains are diagramed in Figure 2. indicating the num·ber of trials taken to reach a criterion of go per cent on 100 consecutivetrials. Deficit is defined as a larger number of triab taken in the"retention" test than in original learning.

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KARL H. PRIBRAM

rather on the situation in which these cues are Im­bedded. Thus, no selective relationship between thevisual discrimination impairment and either of thesetwo classes of environmental variables (cue dimension,situation) is established., I believe this lack of a simplerelationship between the physical dimensions of cuesand the performance of monkeys with inferotemporal

{Ie CLASSICAL DELAYED REAQIONOonop (onlrals 110 (0-330)

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FIGURE g. Bar graph of median scores of the groups delineated inFigure 8. The number of animals per group is indicaled below Ihe.group name; the range from which median scores are taken appearsin parentheses next to the median.

lesions will differentiate these results from those ob­tained when the extrinsic (genicula-striate) visual sys­tem is invaded. Thus, the distinction between suchconcepts as "agnosia" (which might account for theresults of the "situational" experiment) and "acuityloss" (which might account for the results found onvarying the physical dimensions of the discriminanda).which have been traditionally employed to explain thedisparate effects of lesions in the extrinsic and intrinsicsystems, may be revised in more precise terms allow­ing interdisciplinary translation.

A second example of this approach to the functions·of the intrinsic systems is presented'in Figure 8 which

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

DELAYED REACTION

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fl(;{:R£ 10. The upper diagram A represents the sum of the areasof resection of all of the animals grouped as showing a deficit in Figure8 and Figure 9. The middle diagram B represents the sum of the areasof resection of all of the animals grouped as showing no-deficit inFigure 8 and Figure 9. The lower diagram C represents the intersectof the area shown in the upper diagram and that not checkerboardedin the middle diagram. This intersect represents the area invariablyimplicated in delayed reaction performance in these experiments.(Xote that resections within the area stippled in the upper diagramoccasionally result in "deficit" as defined here. However. note also.that a similar "deficit" appears in the non-operate controls in Figure 8.·

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This finding resolves the discrepancies regarding previously describedoccasional occurrence of deficit on delayed reaction following posteriorcortical resections.··· For the purposes of a "Iocalization" procedure,the delayed alternation task appears to be more reliably retained.Nevertheless, as demonstrated here. the results of delayed reactionexperiments may still be useful.)

shows the scores in the deJayed reaction made by theanimals with the lesions presented in Figure 2. Figure9 summarizes these data on the basis of animals withand without deficits defined in the same way as in thecase of visual choice reaction. Figure 10 shows in A thesum of the area of the lesions of the animals withdeficit and in B the sum of the area of the lesions of theanimals without deficit; C shows the intersect of area itand the area not included in B. This area correspondsroughly to another intrinsic system, the anterofrontalsector. \Ve are, thus, ready to investigate another of theintrinsic cerebral systems.

The delayed reaction may be manipulated in a man­ner similar to that which we used in the visual choicereaction. Figures 11 and 12 present the results of suchmanipulations.1 A shows the difference in performancebetween animals with anterofrontal resections and con­trol operates in the traditional delayed reaction. In thistask the animal chooses the cup containing a peanutfrom one of two identical cups, on the basis of a cuepresented sometime prior to opportunity for response.This cue is not present during the delay period or atthe time of response. B shows that (1) when the pre­delay cue is varied from showing a peanut (or object)to the right or to the left of the animal to showing apeanut or a barehand (or two distinct objects), and (2)when the conditions of response are varied to oppor-

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

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FICUllE II. Bar graph comparing the performance of anterofrontaland control (inferotemporal) operates on two types of delayed re­action. Each bar represents the performance of one animal (desig-nated by the number above the bar). Note the successful performanceof anterofrontal operates (comparable with that of controls) when themethod of presentation of predelay cues and opportunity for response I,••~l\

are both changed from a simultaneous, right-left situation (upper ~diagram) to a successive, go-no go situation (lower diagram).'

KARL H. PRIBRAM

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FIGUU 12. Same as Figure 11 except that the indirect method ofcueing was used. Results are comparable to those obtained when pea­nuts are used (direct method).'

tunity for opening or not opening a single centeredcup. animals with frontal lesions perform almost as

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

well as their controls. ·When either the predelay cuesor response conditions are varied alone, such dramaticimprovement of frontal operates' performance doesnot take place. However, as can be seen from Figure 13,m:mipulations of the predelay cue are markedly moreeffecti\"e than manipulations of the response condi-

. tions. In these experiments when the predelay cue waschanged from a spatial to a non-spatial one, frontal ~..operates' performance improved. This might have ¢Ibeen the result of changes in the spatial aspect of thediscriminans. On the other hand, the relevant changemight be the fact that for monkeys the peanuts andobjects used as predelay cues had acquired greater "dis­tincti\"eness" during prior testing than is possible witha right-left choice. Comparing performance on anothertask, spatial alternation, which is also consistentlyfailed by anterofrontal operates, with these animals'performance in a non-spatial object alternation, shouldanswer the question of whether spatiality or "acquireddistinctiveness" of cues is the relevant variable ac­counting for the improved performance of the abovetasks. Figure 14 compares performance in 1,000 trialsof anterofrontal operates and control operates in spatialand object alternation.12 As can be seen, frontal oper-ates are impaired in their performance of both tasks.Thus, spatiality per se cannot be the relevant predelaycue dimension responsible for anterofrontal operates'failure in delayed-response type tasks. Rather, the re-sult of this experiment suggests the hypothesis thatthe remarkably high level of performance achieved byfrontal operates on certain variations of delayed re- ,'-.,.,sponse are due to the "distinctiveness" which the pre- ~

KARL H. PRIBRAM

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FIGUR!: 13. Bar graph comparing the performance of ancerofroncaland control (inferotemporaJ) operates on further variations of thedelayed reaction task. The upper graph represents performance whencues are presenced in right-left positions as in the classical methodbut opportunity for response is go_no go as in the succ~i\·emethod.The lower diagram represents performance ~vhen cues are presentedsuccessively but opportunity for response is unchanged from that usedin the classical method (go right-go left).'

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

delay cues had acquired during prior training. Con­versely, performance decrement. when present in suchanimals, must be considered a function of the distinc­tiveness of the predelay cue. Thus, frontal operates'

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impairment on classical delayed response is a function,not only of the delay; but also of the distinctiveness ofthe predelay cue.

The impairment in choice behavior which followslesions of both intrinsic systems discussed is, therefore,a function of distinctiveness of cues. The effects of re­section of the posterior (inferotemporal) system andthe anterior (anterofrontal) are distinguished in termsof other relevant variables: The posterior system has Abeen related to discrimination behavior which is ~

KARL H. PRIBRAM

modality specific; the anterior system to discrimina­tions made in the presence of a temporal gap betweencue presentation and response.

At this point I should like to turn from the intrinsicsystems. Since one of the functions of this symposiumis to discuss the relation of all of the behavioral sciences,the following experiment is apropos. In this instance,the surgical manipulation involved a portion of thesecond rhinencephalic system,IS the amygdaloid com­plex of the cerebral hemisphere. The environmentalmanipulation concerned a social grOl,lp of eight pre­adolescent male macaques. A dominance ranking ofeach animal with respect to other animals in the group(during feeding) was obtained prior to surgery. Figure15 demonstrates this preoperative hierarchy. Figures16, 17, and 18 show the effect on this hierarchy of bi­lateral amygdalectomy of the three most dominant·animals (one animal operated on at a time). Althoughall lesions are of comparable extent, there are differ-'ences among the operates in direction and degree ofchange in social behavior. Thus, Dave drops from the~ 1 position to become ~8; Zeke, who became the dom­inant animal after Dave's demise, was also sent down­ward in the hierarchy by the resection. Riva, Zeke'ssu-ccessor, however, met with no such fate. On the basisof this and subsequent experiments in which relevantvariables were manipulated separately, it appears thatthe amount of aggressive behavior displayed by the~2 animal toward the operate during the immediatepostoperative period may be critical in determiningthe effect of amygdalectomy. Thus, as in the case ofthe intrinsic systems, complete description of the effects

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.FICL'IU: 16. Same as Figure 15 after bilateral amygdalectomy hadbeen performed on Dave. Note his drop to the bottom of the hierarchy.

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FICURE 18. Final social hierarchy after Dave. Zeke. and Riva haveall had bilateral amygdalectomies. Minimal differences in extent andlocus of the resections do not correlate with differences in the be­havioral results. As noted in the text. Herby's nonaggressive "per­sonality" in the ~2 position of the hierarchy seems the most likelyexplanation of the disparate effects of similar lesions."

TOWARD A SCIENCE OF NEUROPSYCHOLOGY

of brain lesions must include specification of the en­,-ironmental variables which determine the changes inbehavior.

In Summar)': As indicated in the title of this presenta-tion, I have discussed method and data (relationsbetween dependent and independent variables) whichmay lead toward it science of neuropsychology. Con­spicuously undeveloped are the laws (relationships toJa dependent variable of classes of interrelated inde­pendent variables) which form the substance of anyscience. I feel, perhaps erroneously, that there is, asyet, an insufficient scope of data to allow the formula-tion of general laws. However, some of the terms whichmust be included in any rigorous formulation arebeing uncovered.

. As an example, some cerebral systems have beensurgically manipulated on the basis of neuroanatomicaland neurophysiological data and some relationships tobehavior have been described. The cortex of thesesystems has previously been referred to as "associative"on the basis of presumed anatomical connections,physiological "silence," and "clinical" observati9n.The experiments described offer one method of de­lineating more precisely the role of these systems inbehavior. The inferotemporal sector has been selec­tively related to performance of visual choice reactions.Resections of this sector result in impairment of visualchoice reactions, the impairment being proportional tothe distinctiveness of the discrimination as defined bythe difficulty of the task for control animals. The di­mension of "distinctiveness" is related not only to the J

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.KARL H. PRIBRAM

physical parameters of the cue, but also to some "non­cue" (situational) variables determining the response.

A second example concerned the relationship of theanterofrontal sector to choice behavior dependent oncues not present at the t,ime of response. Experimentshave been reviewed which show that this relationshipis insufficiently described by the parameter of temporalcontiguity between pre- and postdelay contingencies,and that "distinctiveness" of the predelay cue is as ~m­

ponant a variable as "time." Thus, the effects of lesionsof both intrinsic systems discussed are a function of thedistinctiveness of the cues upon which the choice be­havior is dependent. The effects of lesions of the poste­rior and anterior systems may be distinguished, how­ever, by other relevant variables: The posterior lesionhas an effect which is modality specific; the anteriorlesion is effective only when choice is dependent on.cues temporally remote from the response.

The third example concerned one of the rhinen­cephalic systems and showed that specification andmanipulation of environmental variables is as im­portant in understanding the relation between brainand social-emotional behavior as in understandingsuch a relationship to choice behavior. The exampleshowed that comparable lesions of the amygdaloidcomplex resulted in diverse effects on the dominanceof a 1:t 1 animal in a social hierarchy depending on theamount of aggressive interaction with the 1:t2 animalduring the immediate postoperative period.

Accumulation of data according to the approachpresehted here should make possible, in the future, asystematization of relationships between neurological

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TOWARD A SCIENCE OF NEUROPSYCHOLOGY

and behavioral data which will constitute a science ofneuropsychology. Though the development of thisscience is dependent on the development of neurologyand psychology, the reductive sibling may be expectedto add impetus to the growth of its less hybrid sistersciences. At present, data gathering. guided by hy­potheses, fills our time and capacity. It is my hope thatthe results of these endeavors may stimulate others tojoin in this approach, for, only when data sufficient inrange and scope are available, will the formulationswhich constitute a science be possible. Our particularscience, neuropsychology, has a special role to fill atthis time: The largest gap in our conceptualizations liesbetween the behavioral and the physiological sciences-a gap paralleling that which existed between the phys­iological and physical sciences a century ago. A com­mon framework for the physical and physiologicalsciences resulted from experiments such as the syn­thesis of urea-from neuropsychological experimentswe may expect the emergence of a common frameworkrelating physiological and behavioral science.

REFERENCES1. Bagshaw. M. H. and Pribram. K. H. Cortical organization in gus­

tation (macaca mu)atta). ]. Neurophysiol., 1953, 16:499'508.2. Blum,]. 5., Chow, K. L., and Pribram, K. H. A behavioral analysis

of the organization of the parieto.temporal'preoccipital cortex.]. compo Neurol., 195°,93:53-100.

3. Gunter, R. The effect of resection of the striate cortex and of theinferoteroporal cortex on a visual brightness discrimination. (Inpreparation.)

4. Lashley, K. S. The mechanism of vision: XVIII. Effects of destroy­ing the visual "associative areas" of the monkey. Genet. Psychol.Monogr., 1948,37: 107-166. :2;-

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5. Mishkin. M. Visual discrimination performance following abla·tions of the temporal lobe: II. Ventral surfaces vs. hippocampus.]. comp. physiol. Psychol., 1954.47: 187- 193.

6. Mishkin. 1\1. and Pribram. K. H. Visual discrimination perform­ance follow:ng partial ablations of ,the temporal lobe: I. Ventralvs. lateral. ]. camp. physiol. Psychol., 1954.47: 14-20.

7. ---. Analysis of the dUcts of frontal lesions in monkey: II.Variations of delayed response. (Submitted for publication to ].camp. physiol. Psycho/.)

8. Pribram. Helen and Barry. J. Further behavioral anal}'sis of theparieto-temporo-preoccipital cortex. (Submitted to ]. NeuTO­physiol.)

g. Pribram. K. H. and Bagshaw. r.I. H. Further analysis of the tcm·poral lobe syndrome utilizing fronto-temporal ablations. ]. camp.

Neurol., 1953. 99:347-375·10. Pribram. K. H. and Fulton. J. F. An experimental critique of the

effects of anterior cingulate ablations in monkey. Brain, 1954.

77:34-44·11. Pribram. K. H. and Kruger. L Functions of the 'olfactory brain.

Ann. N. Y. Acad. Sci., 1954.58: 109-138.12. Pribram. K. H. and Mishkin. i\f. Analysis of the effects of frontal,

lesions in monkey: III. Object alternation. (Submitted for publica­tion to]. compo physiol. Psychol.)

13. ---. Simultaneous and successive visual discrimin:llion by mon­keys with inferotemporal lesions. ]. compo ph)'siol. Ps),chol. (Inpress.)

14. Pribram. K. H .• Mishkin. M.• Rosvold. H. E.• and Kaplan. S. J.Effects on delayed·response performance of lesions of dorsolatcraland ventromedial frontal cortex of baboons. ]. compo phJ$io/.Psychol., 1952.45:565-575.

15. Pribram. K. H. and 'Veiskrantz. L. The effect of selecti\'e resec­tions of portions of the cerebral cortex on conditioned·a\'Oidanceperformance of monkeys. (In preparation.)

16. Riopelle. A. J. and Ades. H. W. Discrimination learning followingdeep temporal lesions. Amer. Psychologist, 1951.6:261 (.-\bstract).

17. Rose. J. E. and Woolsey. C. N. Organization of the mammalianthalamus and its relationships to the cerebral cortex. EEG elin.Neurophysiol.• 1949. 1:391-4°.1.

18. Rosvold. H. E.• Mirsky. A. F.• and Pribram. K. H. Influence ofamygdaleclOmy on social interaction in a monkey group.]. camp.physiol. Psychol., 1954.47:173'178. •

TOWARD A SCIENCE OF NEUROPSYCHOLOGY

Ig. Wilson, W. and Mishkin. M. Survey of the effects of resectIon ofthe striate corte.x and the infratemporal cortex on visually guidedbehavior. (In preparation.)

Acknowledgment

I wish to e.xpress my gratitude to my colleagues. Lawrence Weis­krantz. Lawrence Kruger. William Wilson. and Margaret Varley. fortheir help in generating the ideas set forth here. Stimulating sugges­tions ha\Oe also come from conversations with K. S. Lashley, S. S.Ste\"ens. B. F. Skinner. W. A. Rosenblith, H. L. Teuber. and E. I.Burdock. Special thanks are due Mortimer Mishkin whose continuingcollaboration throughout the studies quoted made this manuscriptpossible.

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