Atypical visuomotor performance in children with PDD

Children with autism spectrum disorders (ASD) frequently encounter difficulties in visuomotor tasks, which are possibly caused by atypical visuoperceptual processing. This was tested in children (aged 9–12 years) with pervasive developmental disorder (PDD; including PDD-NOS and Asperger syndrome), and two same-age control groups (Tourette syndrome and typical developers) using two tasks: a visual and non-visual tactile tracking task (modified from Hermelin & O’Connor 1970 task) and the Developmental Test of Visual-Motor Integration (VMI). Both tasks revealed marked differences between the PDD group and the controls. Confirming Hermelin and O’Connor's findings in ‘classical’ autism, the children with PDD were faster than the controls on the non-visual tracking task, whereas they performed similarly to the controls when they could see the tracks. However, VMI copy scores were lowest for the children with PDD, while their scores on the visual perception and motor coordination subtests did not differ from the controls. The results support observations of an atypical visuomotor performance in children with PDD, which appears to derive from a deviant use of visual information in planning and guiding movements.

► We studied visuomotor skills in boys with lesser variants of autism (PDD).
► Without vision, the PDD group performed better in a tracking task than controls.
► PDD group scores for visual-motor integration (VMI) were poorer.
► The children with PDD did take less time to draw the VMI figures.
► Children with PDD might rely less on visual information in perceptual-motor tasks.