Relationship between biological motion perception and social anxiety in Parkinson’s disease

Abstract

The ability to infer and understand intentions of others through observing their actions is fundamental to our adaptive daily functioning, especially for our daily social interaction. In view of the fact that motoric areas of the brain have been shown to be important for understanding observed actions (i.e., “mirror neurons”), this study aimed to investigate whether individuals who had a degeneration in motoric areas, such as patients with Parkinson’s Disease (PD), might also show compromised ability in perceiving biological actions (biological motion; BM). Twelve PD patients and twelve age- and gender-matched healthy counterparts completed two experimental tasks testing their ability to perceive “global” and “local” BM, and a control task testing their sensitivity to non-BM. When compared to their age- and gender-matched healthy counterparts, we found that PD patients showed intact BM sensitivity, even after controlling for cognitive and affective variables. These findings unexpectedly run counter to the conventional mirror neuron hypothesis. We also tested the role of social anxiety in contributing to perception of BM. Notably, social anxiety and general cognitive status were significant predictors of sensitivity to BM, whereas similar prediction was not observed in non- BM task. All in all, our findings implicated that perception of BM can be modulated by general cognitive status and anxiety towards social situations, which offered insight into developing diagnostic tools or identifying targets of intervention across neuro- and psycho-pathologies.