The aim of the study was to explore the effect of eye movements (saccades and pursuits) on postural stability in children with autism versus typically developing children of comparable age. Postural stability was recorded with a platform (Techno Concept) in seven children with autism (mean age: 6 ± 0.8) while fixating a target or making saccades or pursuit eye movements. Data was compared to that of seven age-matched typically developing children. Surface area and mean speed of the center of pressure (CoP) were measured. Autistic children (AC) were more instable than typically developing children (TD), both in simple as well as dual task conditions. Performing a dual task thus affects AC and TD children in a different way. AC stability is not improved during saccades or pursuit eye movements in the dual task condition; in contrast, saccades significantly improve postural stability in TD children. The postural instability observed in AC during simple as well as dual task supports the hypothesis that such children have deficits in cerebellar functions. 1. Introduction Autism is a common neurodevelopmental disorder that is diagnosed on the basis of anomalies in social interaction, verbal and nonverbal communication, and cognitive flexibility that are apparent before the age of three [1]. It has been noted that between 25% and 50% of diagnosed individuals never acquire functional language [2, 3]. Although not currently included as diagnostic criteria for autism, processing abnormalities across sensory domains are often observed [4] and are included in the Childhood Autism Rating Scale [5] and the Autism Diagnostic Interview-Revised [6] (ADI-R). Abnormalities of motor coordination, posture, and gait are also frequently associated with autism [7]. Postural control observed in children with autism appears to differ from that of typically developing children (TD). Indeed, Gepner et al. [8] and Gepner and Mestre [9] showed that autistic children are more unstable than control children of comparable age; they suggested that the instability observed in these kinds of children could be due to cerebellar deficits responsible for regulation of visual, vestibular, and somatosensory information. Abnormal sensory input integration for good postural control in autistic children has also been reported by Molloy et al. [10] when visual and/or somatosensory inputs were modified or eliminated during postural recording. Gowen and Miall [11] and Rinehart et al. [12] also suggested that a deficit at the basal ganglia and cerebellum level could be at the origin of postural
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