Oculomotor abnormalities parallel cerebellar histopathology in autism. Neurology, Neurosurgery, and Psychiatry, 75, 1359-1361

University of Pittsburgh, Pittsburgh, Pennsylvania, United States
Journal of Neurology Neurosurgery & Psychiatry (Impact Factor: 6.81). 10/2004; 75(9):1359-61. DOI: 10.1136/jnnp.2003.022491
Source: PubMed


To investigate cerebellar function in autism by measuring visually guided saccades.
A visually guided saccade task was performed by 46 high-functioning individuals with autism with and without delayed language acquisition, and 104 age and IQ matched healthy individuals.
Individuals with autism had increased variability in saccade accuracy, and only those without delayed language development showed a mild saccadic hypometria. Neither autistic group showed a disturbance in peak saccade velocity or latency.
The observed saccadic abnormalities suggest a functional disturbance in the cerebellar vermis or its output through the fastigial nuclei, consistent with reported cerebellar histopathology in autism. The pattern of mild hypometria and variable saccade accuracy is consistent with chronic rather than acute effects of cerebellar vermis lesions reported in clinical and non-human primate studies, as might be expected in a neurodevelopmental disorder. The different patterns of oculomotor deficits in individuals with autism with and without delayed language development suggest that pathophysiology at the level of the cerebellum may differ depending on an individual's history of language development.

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    • "Many eye movement studies in autism have addressed the way in which social information affects eye movement and have not examined the characteristics of saccades . For those studies that do test the timing, quality and accuracy of saccades in autism, many have found eye movements to be slow to initiate, inaccurate and highly variable in amplitude [29] [30] [31] [32] [33] [34] [35] but some others have found no differences in latency of saccade initiation or saccade accuracy [36] [37]. "
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    • "In recent years a number of studies have provided evidence for common generators of saccades and microsaccades (Martinez-Conde et al., 2013). The observed higher variability of eye position during fixation in the ASD participants might therefore mirror studies that reported problems in oculomotor control for saccadic eye movements (Goldberg et al., 2002; Takarae et al., 2004; Stanley-Cary et al., 2011), with higher variability of landing positions in ASD participants. "
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