The abnormal audiovisual conflict in Parkinson's disease patients is manifested in perception rather than response.

Audiovisual conflict control is a crucial cognitive function in humans. However, it remains unclear whether and how abnormal audiovisual conflict manifests at periods of perception and response of cognitive processing in Parkinson's disease (PD) patients. In the present study, we recruited 27 PD patients and 22 healthy controls (HC) to complete an audiovisual matching task aimed at investigating audiovisual conflict in PD patients across different processing periods and its relationship with cortical thickness. Behavioral results indicated that abnormalities in audiovisual conflict were observed at period of perception rather than response. Furthermore, the cortical thickness of the left middle frontal gyrus (MFG) in PD patients was positively correlated with sensory interference (with visual interference > auditory interference) at period of perception. Additionally, support vector machine (SVM) analyses revealed that models utilizing conflict at period of perception as a feature achieved higher predictive accuracy for participant classification compared to those employing conflict at period of response. These findings suggested that perceptual deficits may underlie abnormal audiovisual processing observed in PD patients.