Are special abilities in autism spectrum disorder associated with a distinct clinical presentation?

Special abilities may be common in autism spectrum disorders (ASD). The aim of this study was to investigate the clinical presentation of ASD with special abilities. Special abilities were defined based on the Autism Diagnostic Interview-Revised (ADI-R). Based on a sample of 398 children, ages 2-7 years old with ASD, 112 with special skills were compared to an age- and gender-matched group without special abilities (n = 79). The examined measures included autism symptoms severity, adaptive behaviors and head circumference percentile. Children with ASD and special abilities seemed to exhibit significantly less impaired ASD symptoms in the social, communication and stereotyped behaviors and significantly better adaptive skills than individuals with ASD without special skills. Children with ASD and special abilities had a larger head circumference percentile than children without special abilities. Special abilities occurred in 28% of the study participants. Memory skills were the most frequently reported special ability, followed by musical, visuospatial and reading skills. The authors conclude that individuals with ASD and special abilities might represent a distinct ASD subgroup with milder clinical ASD presentation. Larger head circumference in ASD was previously associated with enhanced "local" connectivity which provides detailed information processing and therefore might be related to the appearance of special abilities.