The Impact of Parkinson’s Disease on Social Perception: Preliminary Evidence

Abstract

Besides motor symptoms, people with Parkinson’s Disease (PD) often exhibit social cognition difficulties. The assessment of social cognition in early PD is crucial, as these deficits may impact patients' social interactions and quality of life. The current study used naturalistic, dynamic video clips to examine the ability of individuals with idiopathic PD to perceive speaker intentions in comparison with healthy controls (HC). Neuropsychological evaluation of the PD patients was conducted using the Cognitive Linguistic Quick Test (CLQT). Video stimuli were taken from the Relational Inference in Social Communication database (RISC; Rothermich & Pell, 2015) and contained literal, sarcastic, and teasing scenes. The participant’s task was to identify the speaker’s belief, i.e., if they were sincere or insincere. The results show that in general, all participants had a harder time identifying nonliteral statements such as teasing as insincere when compared to literal statements. A group analysis demonstrated a marginally significant effect between people with PD and HCs, showing that individuals with PD were less accurate in recognizing social intent compared to HC. This difference was possibly driven by changes in cognitive abilities due to the progression of PD. Indeed, analyses for the PD group revealed positive correlations between several cognitive domains, such as attention and memory, and performance on the speaker belief task. Taken together, our study sheds light on the relationship between cognitive mechanisms and social perception impairments in PD and supports the development of targeted tools for diagnosing and treating these impairments.