Abstract
This study aims to evaluate if the reduced sensitivity to global motion observed in some individuals with autism spectrum disorder (ASD) is associated with altered retinal processing. Motion coherence thresholds were measured from individuals with ASD and their family members and compared to the test reference limits derived from control participants. The light adapted electroretinogram (ERG) a- and b-wave amplitudes and peak-times, and photopic negative response (PhNR) parameters were measured from the ASD individuals and their families and compared to those of controls. Abnormally high motion coherence thresholds were found in ASD probands and their family members compared to that in controls, particularly mothers. Altered retinal functions were found in ASD probands and their parents. The PhNR, a- and b-wave time-to-peak were significantly correlated with motion coherence thresholds. The altered retinal function was associated with the age, intelligence and autism severity of the ASD family members. There were associations between the motion coherence and ERG parameters, including smaller amplitudes of the PhNR, and longer time-to-peak of the a- and b-waves and time to the PhNR, compared to those with abnormal motion coherence thresholds. The results showed that global motion coherence deficits were associated with altered retinal function in ASD and their family members. The findings suggest that motion perception deficits follow a familial pattern and that affected mothers may have an increased risk of a child with ASD.