Abstract
BACKGROUND: How levodopa and deep brain stimulation (DBS) modulate the cognitive processing underlying dual-task walking in Parkinson's disease remains poorly characterized, in part due to methodological challenges in capturing neural signals during walking. OBJECTIVES: To evaluate the feasibility and signal characteristics of combining mobile EEG with an inhibitory control task during walking, and to generate preliminary, group-level evidence on how levodopa and DBS may differentially modulate cognitive processing during dual-task walking in Parkinson's disease. METHODS: Ten people with Parkinson's disease completed an inhibitory control task while walking under four levodopa/DBS conditions. Behavioral measures (response accuracy, treadmill-walking speed) and event-related potentials were collected. Data from the off-levodopa/off-DBS condition were compared with data from 37 control participants, and within-subject differences across levodopa/DBS conditions were explored to assess sensitivity of behavioral and mobile EEG measures. RESULTS: Compared with controls, participants with Parkinson's disease off-levodopa/off-DBS demonstrated reduced response accuracy and treadmill-walking speed. Exploratory within-subject analyses suggested that response accuracy improved primarily in the on-levodopa/on-DBS condition compared to the off-levodopa/off-DBS condition. Event-related potentials showed condition-dependent modulation, with levodopa primarily affecting early sensory-perceptual components over bilateral frontocentral regions, and DBS modulating later cognitive components over right prefrontal and right parietal regions. CONCLUSIONS: This proof-of-concept study demonstrates the feasibility and sensitivity of using mobile EEG to assess inhibitory control while walking in Parkinson's disease. The observed condition-dependent behavioral and electrophysiological patterns are hypothesis-generating and provide preliminary guidance for the design of future, adequately powered studies examining combined levodopa and DBS effects on cognition-gait interactions.