Development and Psychopathology

High “intelligence,” low “IQ”? Speed of processing and measured IQ in children with autism

a1 Institute of Cognitive Neuroscience and Department of Psychology, University CollegeLondon
a2 Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, London
a3 University of Western Australia, Nedlands


The uneven profile of performance on standard assessments of intelligence and the high incidence of savant skills have prompted interest in the nature of intelligence in autism. The present paper reports the first group study of speed of processing in children with autism (IQ 1 SD below average) using an inspection time task. The children with autism showed inspection times as fast as an age-matched group of young normally developing children (IQ 1 SD above average). They were also significantly faster than mentally handicapped children without autism of the same age, even when these groups were pairwise matched on Wechsler IQ. To the extent that IT tasks tap individual differences in basic processing efficiency, children with autism in this study appear to have preserved information processing capacity despite poor measured IQ. These findings have implications for the role of general and specific cognitive systems in knowledge and skill acquisition: far from showing that children with autism are unimpaired, we suggest that our data may demonstrate the vital role of social insight in the development of manifest “intelligence.”

c1 Address correspondence and reprint requests to: Uta Frith, UCL Institute of Cognitive Neuroscience, Alexandra House, 17 Queen Square, London WC1N 3AR, UK;