Evidence that the pattern of visuomotor sequence learning is altered in children with autism

Motor deficits are commonly reported in autism, with one of the most consistent findings being impaired execution ofskilled movements and gestures. Given the developmental nature of autism, it is possible that deficits in motor/procedural learning contribute to impaired acquisition of motor skills. Thus, careful examination of mechanismsunderlying learning and memory may be critical to understanding the neural basis of autism. A previous study reportedimpaired motor learning in children with high-functioning autism (HFA); however, it is unclear whether the observeddeficits in motor learning are due, in part, to impaired motor execution and whether these deficits are specific to autism.In order to examine these questions, 153 children (52 with HFA, 39 with attention-deficit/hyperactivity disorder (ADHD)and 62 typically developing (TD) children) participated in two independent experiments using a Rotary Pursuit task, withchange in performance across blocks as a measure of learning. For both tasks, children with HFA demonstratedsignificantly less change in performance than did TD children, even when differences in motor execution wereminimized. Differences in learning were not seen between ADHD and TD groups on either experiment. Analyses of thepattern of findings revealed that compared with both ADHD and TD children, children with HFA showed a similar degreeof improvement in performance; however, they showed significantly less decrement in performance when presentedwith an alternate ("interference") pattern. The findings suggest that mechanisms underlying acquisition of novelmovement patterns may differ in children with autism. These findings may help explain impaired skill development inchildren with autism and help to guide approaches for helping children learn novel motor, social and communicativeskills.