SELECTIVE ATTENTION AND EXECUTIVE CONTROL IN AUTISM SPECTRUM DISORDER AND SCHIZOPHRENIA: AN EYE MOVEMENT STUDY

Background: While specific oculomotor abnormalities are detected in schizophrenia (SCH) patients in prosaccade tasks that assess selective attention and antisaccade tasks that assess executive control, no consensus has been reached regarding saccadic eye movements in autism spectrum disorder (ASD). This study aims to compare prosaccade and antisaccade metrics in ASD and SCH.
Methods: The study included 58 patients with SCH, 26 with ASD, and 48 healthy controls. Participants' eye movements were recorded using EyeLink 1000 Plus, and they performed prosaccade and antisaccade tasks. Participants were expected to look towards the horizontal stimulus in the prosaccade task, and they were expected to look in the mirror direction of the horizontal stimulus in the antisaccade task.
Results: Prosaccade latency in SCH patients was significantly longer compared to controls. The smaller amplitudes was found in SCH patients compared to ASD patients. Prolonged antisaccade latency was observed in the SCH than in the ASD and control groups. Correct antisaccade rate was lower in ASD compared to SCH and controls. The highest uncorrected antisaccade error rates were found in ASD than SCH and controls.
Discussion: Difficulty initiating saccades is prominent in SCH and may be related to selective attention and saccadic decision-making difficulties. More severe executive control impairments have been identified in ASD. Oculomotor measurements may provide a potential cognitive biomarker for the subtyping or subgrouping and monitoring of SCH and ASD, which exhibit heterogeneous clinical features.