IMPAIRMENT IN SHIFTING ATTENTION IN AUTISTIC AND CEREBELLAR PATIENTS

MRI and autopsy evidence of early maldevelopment of cerebellar vermis and hemispheres in autism raise the question of how cerebellar maldeve lopment contributes to the cognitive and social deficits characteristi c of autism. Compared with normal controls, autistic patients and pati ents with acquired cerebellar lesions were similarly impaired in a tas k requiring rapid and accurate shifts of attention between auditory an d visual stimuli. Neurophysiologic and behavioral evidence rules out m otor dysfunction as the cause of this deficit. These findings are cons istent with the proposal that in autism cerebellar maldevelopment may contribute to an inability to execute rapid attention shifts, which in turn undermines social and cognitive development, and also with the p roposal that the human cerebellum is involved in the coordination of r apid attention shifts in a fashion analogous to its role in the coordi nation of movement.