Effects of task prioritization on a postural-motor task in early-stage Parkinson’s disease: EEG connectivity and clinical implication

• Published in: GeroScience Vol. 44; no. 4; pp. 2061 - 2075
• Main Authors: Huang, Cheng-Ya, Chen, Liang-Chi, Wu, Ruey-Meei, Hwang, Ing-Shiou
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.08.2022; Springer Nature B.V
• Subjects: Balance; Basal ganglia; Biomedical and Life Sciences; Cell Biology; EEG; Electroencephalography; Geriatrics/Gerontology; Life Sciences; Molecular Medicine; Movement disorders; Neurodegenerative diseases; Original; Original Article; Parkinson's disease; Patients; Posture; Resource allocation; Functional connectivity; Task prioritization; Dual-task; EEG; Parkinson’s disease
• ISSN: 2509-2715; 2509-2723; 2509-2723
• DOI: 10.1007/s11357-022-00516-4

Appropriate attentional resource allocation could minimize exaggerated dual-task interference due to basal ganglia dysfunction in Parkinson’s disease (PD). Here, we assessed the electroencephalography (EEG) functional connectivity to investigate how task prioritization affected posture-motor dual-tasks in PD. Sixteen early-stage PD patients and 16 healthy controls maintained balance in narrow stance alone (single-posture task) or while separating two interlocking rings (postural dual-task). The participants applied a posture-focus or supraposture-focus strategy in the postural dual-task. Postural sway dynamics, ring-touching time, and scalp EEG were analyzed. Both groups exhibited smaller postural sway size, postural determinism, and ring-touching time with the supraposture-focus versus posture-focus strategy. PD patients exhibited higher mean inter-regional connectivity strength than control subjects in both single and dual-task postural conditions. To cope with dual-task interference, PD patients increased inter-regional connectivity (especially with the posture-focus strategy), while control subjects reduced inter-regional connectivity. The difference in mean connectivity strength between the dual-task condition with supraposture-focus and single-posture condition was negatively correlated to the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) part III total scores and hand-related sub-scores. Our findings suggest differential task prioritization effects on dual-task performance and cortical reorganization between early-stage PD and healthy individuals. Early-stage PD patients are advocated to use a supraposture-focus strategy during a postural dual-task. In addition, with a supraposture-focus strategy, PD patients with mild motor severity could increase compensatory inter-regional connectivity to cope with dual-task interference.