Structure of intelligence

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range. Some recent findings suggested that children with r e a d i n g retardation h a v e a b a s i c difficulty i n the c r o s s m o d a l t r a n s f e r of i n f o r m a t i o n f r o m the auditory, to the v i s u a l m o d a l ity (e.g., c o n v e r t i n g a u d i t o r y taps into Visual dot p a t t e r n s . ) R e c e n t reSearch b y the p r e s e n t a u t h o r s i n d i c a t e d t h a t s y m b o l i c m e d i a t i o n was a n e c e s s a r y c o n d i t i o n for c h i l d r e n to solve p r o b l e m s i n v o l v i n g t e m p o r a l ly p r e s e n t e d s t i m u l i r e g a r d l e s s of t h e m o d a l i t y . It w a s t h e r e f o r e h y p o t h e s i z e d that the d i f f i c u l t y t h e ret a r d e d r e a d e r s e x p e r i e n c e d ,,'`,as not in c r o s s m o d a l transfer b u t r a t h e r in a p p l y i n g r e l e v a n t Concepts o f s y m bols to the stimuli c o n f r o n t i n g them. I n o r d e r to test this ]aypothesis, a series of e x p e r i m e n t s w e r e c a r r i e d out on 13 n o r m a l a n d 13 r e t a r d e d readers, m a t c h e d for a(re IQ, a n d vocabulary. T h e following e x p e r i m e n t s w e r e conducted: ( 1 ) To d e m o n s t r a t e that t h e d e f e c t w a s not in e r o s s m o d a l t r a n s f e r p e r se, the s a m e stimuli offered in the reported experiments were again presented, b u t this t i m e tl)ey w e r e pres e n t e d i n t r a m o d a l l y (e.g., v i s u a l l y presented s e q u e n c e s of lights h a d to b e m a t c h e d to v i s u a l l y p r e s e n t e d patterns of d o t s ) . O n t h e ten p r o b l e m s of this task, the r e t a r d e d l,caders perf o r m e d s i ~ a i f i e a n t l y less well t h a n d i d the n o r m a l r e a d e r s s u p p o r t i n g our hypothesis. ( 2 ) To d e m o n s t r a t e that the norm a l a n d r e t a r d e d readers d i d not differ in t h e i r a b i l i t y to p e r c e i v e ( " r e a d " ) the dot p a t t e r n s , i n d i v i d u a l (lot p.-~tterns w e r e p r e s e n t e d to tile c h i l d r e n . T h e c h i l d t h e n h a d to select w h i c h one of three p a t t e r n s w a s i d e n t i c a l to the" p a t t e r n h e h a d just seen. T e n such p r o b l e m s w e r e pro-

sented. T h e r e ,,',,as no s i g n i f i c a n t diff e r e n c e b e t w e e n tile n o r m a l a n d ret a r d e d r e a d e r s on this task. ( 3 ) S u b s e q u e n t to these p r o b l e m s , all c h i l d r e n r e p o r t e d that t h e y h a n d l e d t h e tasks b y c o n v e r t i n g the stimuli into n u m b e r s a n d t h e n m a t c h i n g these n u m b e r s to the a p p r o p r i a t e dot p a t t e r n s . T o test the relati,)'~ efficiency w i t h w h i c h t h e two g r o u p s perf o r m e d this c o n v e r s i o n into symbols, t h e c h i l d r e n w e r e p r e s e n t e d w i t h ten series of l i g h t s e q u e n c e s . A f t e r e a c h s e q u e n c e , t h e y w e r e asked to r e p o r t exactly hove m a n y lights vec~re seen; if t h e r e was a p a u s e b e t w e e n the lights; etc. (e.g., two lights, p a u s e , one light, p a u s e , two l i g h t s ) . O n this task, t h e r e t a r d e d r e a d e r s p e r f o r m e d significantly more poorly than did the n o r m a l readers, s u p p o r t i n g the hy~pothesis that the f o r m e r h a d diffictdty in a p p l y i n g the correct m e d i a tors to t h e s t i m u l i p r e s e n t e d . T h e i r e q u a l a b i l i t y to n o r m a l r e a d e r s on t h e s e c o n d e x p e r i m e n t suggests that t h e y c a n apply, m e d i a t o r s to s p a t i a l l y p r e s e n t e d stimuli, b u t h a v e difficulty in h a n d l i n g t e m p o r a l l y p r e s e n t e d stimuli. T h e r e a s o n s for the difficult), r e t a r d e d r e a d e r s h a v e in d e a l i n g w i t h tempor'al p h e n o m e n a r e m a i n to be investigated. Structure of Intelligence ROBr_:I~T

L.

TIIo~xmrzE,

Ph.D.,

Teachers College, Columbia Unioersity I n t e l l i g e n c e started its c a r e e r in p s y c h o l o g y as a largely, h e r e d i t a r y a n d u n i t a r y trait. O v e r the past 60 years, reseairch has b e e n c o n c e r n e d at s o m e times w i t h t i l e r e l a t i v e roles of n a t u r e an(l n u r t u r e in i n t e l l e c t u a l (levelopnaent, a n d at other times w i t h

443 the extent to which the observable manifestations of intellect are one and the extent to wliich they are many. With the present concern f o r the culturally deprived or the culturally different, conventional intelligence tests have come under renewal attack. In t h e light o]? these issues, how s h a l l we conceive of intelligence in the 1960"s? In the first place, we must recognize that no clear or useful distinction is possible between aptitudes and achievements. Any measurement is a measure of " developed """ " ' abdltles. The best predictor of later academic performance turns out to be ,not a measure of intelligence b u t a measure of reading achievement. Furthermore, there is no guarantee that non-verbal, non-language tests of ability are any more culture-free than are verbal tests. To the extent that cultural factors depress intellect, the effect is ve~, pervasive and far-reaching. As to the structure of intellect, debate hinges loss on the nature of the f a c t s t h a n on the most useful interpretation. If "'intelligence" is replaced by a h o s t of more limited factor scores, it must be recognized that these factors are thems.elves related at a Jiigher level o f abs'tracti0n. On the other hand, a single:general factor of intellec t is quite iiaadequate to account for the observed complexity of individual differences, and must be supplemented b y more specialized cog~iitive abilities. Depending 'upon the focus of our practical concern, it may be more advantageous sometimes to emptaasize and maximize the common core of unity in intellect and" sometimes to emphasize and maximize the specific ~and diverse capabilities.

T h e A s s e s s m e n t o f A n o m a l i e s in Intellectual Development

ALBERT I. RAZrX, Ph.D., Michigan

State University F o l l o w i n g a b r i e f review of the nature of intelligence a s )defined empirically :and o p e r a t i o n a l l y by intelligence tests, t h e paper will focus on t h e literature that deals w i t h developmental abnormalities gleaped from test findings. Specifically; studies concerning t h e following p h e nomena t h a t a r e i'eflected in intelligence t e s t results will be considered: (1) The low gradient in the curve of intellectual g r o w t h throughout the childhood years ....its characteristics and fluctuations. (2) "Developmental arrest" in adolescence, as w e l l a s in earlier years. (3) Unevenness in mental development, scatter of abilities, and special disabilities. Special consideration of the "'idiot s a v a n t " phenomenon ",~dll be given in view of i t s theoretical implications. These phenomena and, p e r h a p s "pseudo mental r e t a r d a t i o n " will be related to the e'ndogcnous-exogenous dichotomy, to brain pathology and stimulus, deprivation (environmental). Fin,ill)', the criticism of file conc e p t - o f intelligepce (implicit in i n telligence tests) will b e taken up and the studies, and~proposed programs, of cognitive .development (e.g., concept formation, abstraction, etc.) will be examined. S u r v e y of F a m i l i a l Corrclatipns in Measured I n t e l l e c t u a l F u n c t i o n s

L~ssY F. JAnvir:, Ph.D., M.D., and L. ERLEN~MEYER-KLXILING, ph.D.,

Nelo York State Psycl~iatrie Institute