Fig. 1: Group design and clinical characteristics of non-motor symptoms in PD.

a Group design: PD patients with MoCA scores ≤25 were assigned to the PD-MCI group (22 individuals), while PD patients with MoCA scores >25 were assigned to the PD-NC group (23 individuals). b Clinical characteristics of non-motor symptoms: MMSE Mini-Mental State Examination, MoCA Montreal Cognitive Assessment, PDQ-39 39-Item PD Questionnaire. c Clinical characteristics of MoCA subscales: The subscales include visuospatial and executive, short-term memory, attention, language, abstraction, and orientation.