Asperger Syndrome, Autism and Attention Disorders: A Comparative Study of the Cognitive Profiles of 120 Children

Abstract

The Wechsler Intelligence Scale for Children-Revised (WISC-R) was applied (in a Swedish version) in 120 children with Asperger syndrome, autistic disorder, and attention disorders. Using stepwise logistic regression analysis, the WISC's discriminating ability was investigated. The overall rate of correct diagnostic classification was 63%. Further, WISC profiles were analysed within each group. The group with autistic disorder was characterised by a peak on Block Design. The Asperger syndrome group had good verbal ability and troughs on Object Assembly and Coding. The group with attention disorders had troughs on Coding and Arithmetic. The results suggest that Kaufman's Verbal Comprehension, Perceptual Organisation and Freedom from Distractibility factors rather than verbal IQ and performance IQ account for the variance on the WISC. Furthermore, the Asperger syndrome and autistic disorder groups differed in respect of "fluid" and "crystallised" cognitive ability.

Brief Report: The Level and Nature of Autistic Intelligence Revisited

“…Here, the exclusive use of Raven IQs could lead to a systematic underestimation of true intellectual abilities. Numerous previous studies have shown relatively better Wechsler verbal IQ for individuals with Asperger syndrome and relatively better Wechsler performance IQ in individuals with autism (e.g., Miller and Ozonoff 2000;Mottron 2004;Ehlers et al 1997;Hayashi et al 2008). Those patterns have been equated with higher fluid intelligence in autism and higher crystallized intelligence in Asperger syndrome (Ehlers et al 1997), which would indeed predict underestimation of IQ in Asperger syndrome by tests of fluid intelligence such as the Raven.…”

Neurocognitive stability in Asperger syndrome, ADHD, and reading and writing disorder: a pilot study

“…All diagnostic groups scored higher on the Picture Completion subtest at follow-up. Children with neuropsychiatric problems often score high on this subtest (Ehlers et al 1997), possibly using the ability to focus on details, which may be considered both an asset and a reflection of underlying impairment in these children. This subtest is not a reliable indicator of cerebral damage (Kaufman 1994, Lezak 1995 and 'the nature of the task is not as heavily demanding of adequate brain functions as some of the other Wechsler subtests' (Reitan and Wolfson 1992, p 107).…”

“…Analysis of factor scores according to Kaufman provide good measures of particular sets of cognitive abilities (Kaufman 1994, Ehlers et al 1997). However, a more refined analysis of cognitive profiles, making use of all the various tests and subtests may provide a more striking reflection of the unevenness of neuropsychological performance.…”

“…Children with AS tend to score higher for VIQ than PIQ and lower for fluid than crystallized abilities (Szatmari et al 1990, Ehlers et al 1997). …”

“…Different cognitive profiles on the WISC are found for children with AS (Wolf and Barlow 1979, Pomeroy and Friedman 1987, Szatmari et al 1990, Ehlers et al 1997, ADHD (Kaufman 1979), and RDWD (Wechsler 1992). Children with AS tend to score higher for VIQ than PIQ and lower for fluid than crystallized abilities (Szatmari et al 1990, Ehlers et al 1997).…”