Motion perception in autistic disorders: a functional MRI study

Background: Individuals with Autistic Disorder (AD) show impairments in social interaction and communication, and stereotyped interests and repetitive behaviour. Difficulties processing biological motion have been described previously and might be related to impaired imitation abilities in AD.

Objectives: To assess neuronal activation during the perception of biological motion in AD and control individuals, to compare reaction times during processing biological motion information, to assess correlation with phenotypic data.

Methods: Neuronal activation during the perception of biological motion was compared in 15 individuals with AD and 15 age, IQ, and sex matched controls. Correlation analyses with neuronal activation pattern and performance in a computer based reaction task were calculated for a measure of social interaction, ADI-R subscales, imitation and gross motor abilities.

Results: Different neuronal activation patterns as well as slower reaction time to perceive biological motion were observed in AD compared to control individuals. Imitation abilities strongly correlated with neuronal activation in the inferior parietal lobule.

Conclusions: This study is the first fMRI study on biological motion perception in AD, showing decreased neural activation and specific correlation patterns with activation in brain regions and networks which previously have been found to be affected in AD.