Cognitive profiles in pervasive developmental disorders

Objective. - This study investigated the cognitive skills in pervasive developmental disorders (PDD). Methodology. - Two groups of children participated in this study, 39 individuals with autism and 18 individuals with Asperger syndrome. Each participant was assessed by the Wechsler scales: WPPSI-III, WISC-III or WISC-IV. Results. - Children with Asperger syndrome have VIQ more than PIQ and the children with autism have VIQ less than PIQ. The performances in "block design" task vary according to the cognitive level and not according to the PDD type. The high-functioning autistic children show high performance in "block design" task. Children with Asperger syndrome revealed impairments in the "understanding of social situations" task. Discussion. - Individuals with autism have a verbal intelligence quotient lower than individuals with an Asperger syndrome. Several hypotheses have tried to explain verbal differences between children with autism and Asperger syndrome. A first hypothesis proposed a developmental convergence between these two groups. A second hypothesis suggested that communication and social interaction impairments could be implicated in verbal skills. A third hypothesis supported that individuals with Asperger syndrome could develop a specific cognitive style. Children with autism have spatial and perceptive capacities better than verbal capacities. These performances could be interpreted as the expression of a specific cognitive style based on the visual analysis of the detail. Conclusion. - The low-functioning children with autism have a cognitive profile with PIQ more than VIQ and high skills in spatial organization. The high-level children with autism have a cognitive profile with PIQ more than VIQ and high skills in spatial abstraction. Children with Asperger syndrome have a profile VIQ more than PIQ profile, they are particularly good in verbal learning notably vocabulary. (c) L'Encephale, Paris, 2012.