Ocular Fixation Abnormality in Patients with Autism Spectrum Disorder.

We examined the factors that influence ocular fixation control in adults with autism spectrum disorder (ASD) including sensory information, individuals' motor characteristics, and inhibitory control. The ASD group showed difficulty in maintaining fixation especially when there was no fixation target. The fixational eye movement characteristics of individuals were consistent regardless of the presence or absence of a fixation target in the controls, but not in the ASD group. Additionally, fixation stability did not correlate with an ability to suppress reflexive saccades measured by an antisaccade task. These findings suggest that ASD adults have deficits in converting alternative sensory information, such as retinal signals in the peripheral visual field or extraretinal signals, to motor commands when the foveal information is unavailable.