Evidence for a deficit in procedural learning in children and adolescents with autism: Implications for cerebellar contribution

To examine the hypothesis that abnormalities in those cognitive functions f or which cerebellar components have been implicated contribute to the patho physiology of autism, tests of judgment of explicit time intervals and proc edural learning were administered to 11 participants with autism and 17 age -and-IQ-matched controls. Results indicated that the group with autism demo nstrated significant impairments in procedural learning compared with the g roup of controls. No significant difference in judgment of explicit time in tervals was found. The data suggest that deficits in procedural learning ma y contribute to the cognitive and behavioral phenotype of autism; these def icits may be secondary to abnormalities in cerebellar-frontal circuitry.