Neuropsychologia,1977, Vol 15, pp 675 to 680 PergamonPress.Printedin England NOTE POOR PERFORMANCE OF RIGHT BRAIN-DAMAGED PATIENTS ON RAVEN’S COLOURED MATRICES: DERANGEMENT OF GENERAL INTELLIGENCE OR OF SPECIFIC ABILITIES? G GAINOTTI, C CALTAGIRONEand G MICELI Clinic for Nervous and Mental Diseases, The Catholic University, Largo A Gemelli, I-Roma, Italy (Received 16 December 1976) Abstract-Two groups of 170 left and 173 right brain-damaged patients were given the Raven’s Coloured Matrices, in order to study the influence of the hemispheric side of the lesion on this test of visual-spatial intelligence A significant difference was found between the two hemispheric groups, the right brain-damaged patients scoring worse than the left hemisphere-damaged subjects Furthermore, patients with right hemispheric lesions showed a striking tendency to neglect the responses lying on the left side of the page, whereas subjects with left hemispheric damage showed only a mild tendency to neglect the alternatives lying on the right half of the sheet The worse performances obtained on the Coloured Matrices by right brain-damaged patients seemed due for the most part to unilateral spatial neglect These findings suggest that the bad performances of patients affected by retro-rolandic right hemispheric lesions are not due to a general intellectual impairment, but rather to the detrimental effect of unilateral spatial neglect and of a general disorder in visual-spatial analysis RESULTS obtained on Raven’s Progressive Matrices by patients affected by localized cerebral lesions can be due to three main factors: -the intellectual status of the patient [l-3]; -his ability in visual-spatial analysis [4-61; -the presence and severity of unilateral spatial neglect [7-81 The complexity of the factors underlying the patient’s performance can account, in part at least, for the conflicting results reported in the literature ARRIGONI and DE RENZI 191, on the one hand, found significantly lower scores in patients with unilateral left hemisphere lesions PIERCYand SMYTH [4], on the other hand, reported much lower scores on the Raven test in patients with right hemisphere damage Still other authors [5,6, 10,l l] have reported no significant predominance of either the left or the right brain-damaged patients In a very well controlled study, the problem has again been taken up by BASSOet nl [12], who have shown that among the patients affected by localized cerebral lesions two groups are significantly impaired on the Raven’s Coloured Matrices: (a) Right brain-damaged patients with visual field defect; and (b) left brain-damaged patients with aphasia According to BASSOet al [12] these findings support the notion that two cerebral areas are critical for intelligence: (a) the retro-rolandic areas of the right hemisphere; and (b) a region of the left hemisphere overlapping the language areas These conclusions are of great interest for the students of brain behaviour relationships They raise the question, however, whether the poor performance of the right brain-damaged patients is really due to general intellectual deterioration rather than to more specific defects, such as spatial heminattention or impairment of visual perception BASSOet al [12] have themselves discarded this hypothesis because the interiority of the right brain-damaged patients with visual field defects “persisted even when the Raven scores were adjusted for the scores obtained on a test assumed to assess the severity of the above deficits” None the less, the conclusions of BASSO et al seemed to us at variance both with other data not only in our own experience but also in the earlier literature For example, ZANGWILL and co-workers 113-151 have shown in a series of classical papers, that patients with posterior lesions of the right hemisphere may present signs of visual spatial agnosia at every level of psychological response, in absence of defects of general 675 676 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA NOTE intelligence In more recent years, GAINOTTIand TIACCI 1161have shown that patients with unilateral spatial neglect perform worse than other right brain-damaged subjects on tasks of visual spatial analysis; and OXBURY et al 1171 have demonstrated that this difference cannot be attributed to a general intellectual deterioration The present study was, therefore, undertaken to investigate further the relationship between poor performance on the Raven Coloured Matrices of patients with right cerebral damage and unilateral spatial neglect In particular, we have focused attention on the following points: (1) Is it possible to demonstrate a significant difference between the performance of right and left braindamaged patients on the Coloured Matrices? (2) Does the tendency to neglect the designs lying on the side of the page contralateral to the locus of of lesion differ significantly as between right and left hemisphere-damaged patients? (3) Are the poor scores of right brain-damaged patients due at least in part to unilateral spatial neglect? MATERIALS AND METHODS Subjects The present research was carried out on two groups of 170 left and 173 right brain-damaged patients The diagnosis of hemispheric damage was made on the ground of the clinical symptoms, supplemented by the available EEG, brain scan and neuroradiological findings No selection was made in forming the groups, and only the following patients were excluded from the study: (a) Those who considered themselves (or were reported by their relatives) to be left-handed; (b) those who showed impaired consciousness or were absolutely unable to maintain the set necessary to carry out the task; (c) those whose case history or clinical picture pointed to diffuse or clearly bilateral cerebral damage No significant difference could be found between right and left brain-damaged patients with respect to age, educational level and aetiology of illness Testing procedures The Raven’s Coloured Progressive Matrices were given to all patients without time limits For each test problem the subjects were required to point to the item they thought to be the correct choice and the examiner noted it on the record sheet A failure to respond on any problem was counted as an error The maximum score was 36 In order to assess the possible significance of unilateral spatial neglect in reducing the scores of right and left brain-damaged patients, it was decided to measure position preference according to a method devised by COSTAet al (8) and to compare position preference scores in the two hemispheric groups The position preference scores were determined by computing for each patient the difference between the number of alternatives chosen on the side of the page ipsilateral to the damaged hemisphere and the number chosen on the contralateral side of the sheet (ipsilateral-minus-contralateral score) With an error-free performance, this difference would be zero, because correct responses are equally distributed among the right, the center and the left positions RESULTS Performance ofright and left brain-damaged patients on the Raven Colorrred Matrices The mean scores obtained by the right and left brain-damaged patients are shown in Table 1: Table Scores obtained by right and left brain-damaged Right brain-damaged patient (N = 173) Mean scores S.D x = 16, 375 6,456 patients on Raven’s Coloured Matrices Left brain-damaged patients (N = 170) y = 18, 608 6, 686 t 3, 134 P s; oXlO A significant difference was found to exist between the two hemispheric groups, the right brain-damaged patients scoring significantly lower than those with left-sided brain damage Relationship between hemispheric to the damaged hemisphere locus of lesion and tendemy to neglect the test items on thepage zyxwvutsrqponmlkjihgfe contralateral Figure shows the distribution of the position preference scores in our two groups: It is apparent from inspection of this that right brain-damaged patients show a much more marked position preference than the left brain-damaged patients In order to control the statistical value of the prevalence of position preference scores among the right hemi$pheric patients, we took as cut off point between normal and pathological performances the position preference of which, according to COSTA et al [S], has a 677 NOTE Median value of the pathological position preferenie scores +I I t36 Right B Left FJG Distribution brain-damaged brain-damaged potients patients of the position preference scores in right and left brain-damaged patients probability of occurrence of less than 0.01 in normals The number of patients having an abnormal score in the expected (positive) direction was 96 (55 %) in the right group and 37 (22%) in the left group This difference was found to be highly significant (x2 = 41, 08; P < 0X1001) A further analysis was undertaken to ascertain whether not only the incidence but zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLK also the strength of positionpreference was higher in fhe right hemispheric group The median value of the pathological position preference scores (19.35) was taken as cut-off point between mild (p.p +) and severe (p.p + +-) forms of position preference Fifty-two right and only left brain-damaged patients showed the more severe form of position preference (p.p + +), whereas 44 right and 29 left hemisphere-damaged patients showed only a mild tendency (p.p +) to select the alternatives lying on tilt half of the page ipsilateral to the damaged hemisphere This difference was also found to be highly significant (x2 = 11,41; P < 0.001) Relationships between position preference Acores and performance obtained on the Coloured M atrices In order to ascertain whether the poorer performance on Raven’s Matrices by right hemispheric patients was due, in part at least, to the tendency to neglect the items lying on the left half of the sheet, both right and left brain-damaged patients were divided into three subgroups, according to both presence and strength of the pcsition preference Table shows the scores obtained on the Coloured Matrices by right and left brain-damaged patients respectively, with a positionipreference (p.p.) score lower than +7 (p.p -), a p.p, score ranging between + and + 19 (pp i-) and a p.p score higher than 19 (p.p + +) These data show that there is no significant difference between right and left brain-damagedpatcents when subjects belonging co the same position prejtirence group are compared On the other hand a highly significant di&rence is found, within each hemispheric group, between patients without position preference (p.p -), subjects with mild position preference (p.p +) and patients with marked tendency to neglect the alternatives ly ing on the halfsheet contralateral to the damaged hemisphere (p.p + +) Thesedata suggest that the tendency to select the responseslying on the halfsheet ipsilateral to the damaged hemisphere, paying little or no attention to the contralateral half of the page, is an important factor in reducing the performance not only of right, but also of the left brain-damaged patients However, since both the incidence and strength of position preference were significantly higher in the right hemispheric groups, these results also suggest that the poorer performance of theright brain-damaged patients was due for the most part to unilateral spatial neglect DISCUSSION The main results of the present study can be summarized as follows: (a) If the Coloured Matrices are administered to large groups of unselected patients with unilateral 678 NATE Scores obtained on the coloured matrices by right and left brain-damaged patients without (p.p -), Table zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA with slight (D.D +) and with marked (p.0 _ _ + +) position preference Right brain-damaged patients (N = 173) X = 20,434 P.P (N = 77) Left brain-damaged patients (N = 170) x1 = 19, 969 P.P (N = 133) p.p -t y1 = 14, 827 (N = 29) t = 7,249 (P < 0.001) P.P TV+ z = 10,460 0, 525 n.s I, 128 ll.S I, 339 “ S t = 3, 205 (P < 0.005) p.p + f z 1= 8,875 (N = 8) (N = 521 P t = 4, 133 (P < 0X01) t = 4, 167 (P < 0.001) p.p -t y = 16, 071 (N = 44) t brain-damage, right hemispnere-damaged patients obtain significantly lower scores than patients with damage restricted to the left hemisphere (b) The tendency to neglect information on the half sheet contralateral to the damaged hemisphere is dramatically more in evidence in cases in which the lesion is restricted to the right hemisphere (c) Patients who pay little or no attention to information lying on the half page contralateral to the damaged hemisphere obtain significantly lower scores on the Coloured Matrices than patients who show no clear position preference These findings would appear to cast some doubt on the assumption of BASSOet al [12] that “there is an area in the right hemisphere, probably adjacent to that serving discrimination of visual information, which is critically involved in the eduction of the logical relationships existing among different patterns” Our data seem, indeed, to suggest that the deficit shown on the Coloured Matrices by right brain-damaged patients with visualfield defects is not intellectual in nature, since their poor results appear to be chiefly to unilateral spatial neglect, On the other hand, it should be acknowledged that the association between the presence of uni- lateral spatial neglect (position preference) and the impairment shown on the Coloured Matrices does not necessarily mean that poor performance on this test was due only to the effect of position preference The alternative hypothesis can also be advanced that it was due in part to the detrimental effect of spatialneglect and in part to damage to a region ofthe brain subserving a specialized (visual-spatial) form of intelligence This area, when damaged, must also be regarded as responsible for the production of unilateral neglect This second hypothesis is not definitely at variance with the results of the present research and is in part supported by some data obtained by ZAIDEL and SPERRY[t8] in patients with cerebral commissurotomy We have not attempted to test this hypothesis owing to the difficulty of finding a test of visual-spatial intelligence that does not require lateral spatial exploration However, since the problem seemed to us interesting enough, we have constructed a new form of the Coloured Matrices that, without changing the essential features of the original task, is nevertheless much less sensitive to the presence of unilateral spatial neglect This new form of the Progressive Matrices is actually in use in our laboratory and we hope that it will offer us the opportunity of testing more adequately the hypothesis that there is an area of the right cerebral hemisphere which is involved in the intellectual processing of visual-spatial data REFERENCES SPEARMAN,0 Theory of a general factor Br J Psychol 36,117-131, 1946 RAVEN, J C Standard Progressive Matrices H K Lewis, London, 1938 RAVEN,J C Guide to Using the Coloured Progressive Matrices H K Lewis, London, 1973 COSTA,L D and VAUGHAN,H G Performance of patients with lateralized cerebral lesions-l and perceptual tests .I nerv ment Dis 134, 162-168, 1962 Verbal PIERCY,M and SMYTH,V G Right hemisphere dominance for certain non-verbal intellectual skills Brain 85, 775-790, 1962 GAINOTTI,G and TIACCI, C Sui rapporti fra aprassia costruttiva, agnosia visuo-spaziale e negligenza spaziale unilaterale Riv Patol ner ment 93, 103-l 16, 1972 GAINOTTI,G Les manifestations de negligence et d’inattention pour I’hemispace Cortex 4, 64-91, 1968 COSTA,L D., VAUGHAN,H G., JR., HORWITZ, M and RITTER,W Pattern of behavioral deficit associated with visual spatial neglect Cortex 5, 242-263, 1969 ARRXOONX, G and DE RENZI, E Constructional apraxia and hemispheric locus of lesion Cortex 1, 170-197,1964 NOTE 679 10 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA DE RENZI, E and FAGLIONI,P The comparative efficiency of intelligence and vigilance tests in detecting hemispheric cerebral damage Cortex 1,41&433, 1965 11 COL~NNA, A and FAGLIONI, P The performance of hemisphere-damaged patients on spatial intelligence tests Cortex 2,293-307, 1966 12 BASSO,A., DE RENZI, E., FAGLIONI,P., SCO~I, G and SPINNLER,H Neuropsychological evidence for the existence of cerebral areas critical to the performances of intelligence tasks Bruin 96,715-728,1973 13 PATERSON,A and ZANGWILL, L Disorders of visual space perception associated with lesions of the right cerebral hemisphere Bruin 67, 331-358, 1944 14 MCFIE, J., PIERCY,M and ZANGWILL, L Visual spatial agnosia associated with lesions of the right hemisphere Brain 73, 167-190, 1950 15 ETTLINGER,G., WARRINGTON,E and ZANGWILL, L A further study of visual-spatial agnosia Bruin 80, 335-361, 1957 16 GAINOTTI, G and TIACCI, C The relationships between disorders of visual perception and unilateral spatial neglect Neuropsychologiu 9,451-455, 1971 17 OXBURY, J M., CAMPBELL,D C and OXBURY,S M Unilateral spatial neglect and impairments of spatial analysis and visual perception Bruin 97, 551-564, 1974 18 ZAIDEL, D and SPERRY,R W Performance on Raven’s colored progressive matrices test by subjects with cerebral commissurotomy Cortex 9, 34-39, 1973 680 NOTE Zwei Gruppen van 170 links- und 173 rechtshirnig geschsdigten Patienten wurden mit dem RAVEN-Test gepriift(mit &n RAVENS Coloured Matrices), urnfestzustellen, welchen Einflu6 die Hemisphlre als Verletzungssitz in diesem Test zur optisch-rrumlichen IRtelligenz hat Ys wurde eitisignifikanter Unterschied zwischen den beiden HemisphlrenGruppen gefunde?, wobei die rechtshirnig geschldigten Patien-tenschlechter abschnitten als die 1inkshemisphBrisch gesch%digter Dariiberhinaus zeigteq die Patienten mit rechtshemisph4rischen Verletzungen eine ausgepragte Neigung, die auf der linken Seite des Blattes gelegenen Partien ZU vernachlzissigrl,w4hrend.die Versuchspersonen mit linkshemisph6rischer Sch&di&u??gnur wenig ZUT Vernachl~ssiQxI~ der entsprechenden Partien in der rechten Hrilftedes Blattes neigten Die schlech&ren Leistungen, die bei der Untersuchung rechtshirnig Geschadigter mit den RAVEN-Test erzielt wurden schienen zum grsfltenTeil auf den unilateralen Neglect zuriickzufiihren zu sein Diese Befunde sprechen dafiir,daR schlechte Leistungen bei Patienten mit retrorolandischen TechtShemiSphariSchen Sct#ligungen nicht auf einer eenerellen intellektuellen MinderunE;bzsieren, sondern au‘ der nachteiligen Wirkung eines unilateraleriNeglects und eixr wnerellen SMrun,rrder FYhiSkeit der optisch-r&xnlichen ,x Analvse ... lying on the side of the page contralateral to the locus of of lesion differ significantly as between right and left hemisphere -damaged patients? (3) Are the poor scores of right brain- damaged patients. .. RESULTS Performance ofright and left brain- damaged patients on the Raven Colorrred Matrices The mean scores obtained by the right and left brain- damaged patients are shown in Table 1: Table Scores... pathological position preferenie scores +I I t36 Right B Left FJG Distribution brain- damaged brain- damaged potients patients of the position preference scores in right and left brain- damaged patients probability