PD patients report higher arousal than controls when observing walking tasks, with arousal increasing with environmental challenge (natural>built; high>moderate>low demand) while valence ratings are similar across groups.

Although not mechanistic or directly therapeutic, the work highlights heightened emotional reactivity to gait challenges in PD, which can inform assessment, rehabilitation strategies, and environment- or behavior-focused interventions to mitigate fall risk and anxiety.

INTRODUCTION: Gait disturbance is a hallmark of Parkinson's disease (PD) that worsens under complex conditions and might change according to environmental context. In this study, we aimed to determine how observing gait demands and context affects arousal and valence in PD. METHODS: Fifty PD participants and 50 healthy subjects (HS) completed a questionnaire evaluating arousal and valence of gait observation. This consisted of 36 videos showing a person walking, which were categorized based on two factors: (i) context: natural or built environment; and (ii) walking demand: Low-Demand (LD, e.g., usual walking along a street); Moderate-Demand (MD, e.g., walking on narrow surfaces); High-Demand (HD, e.g., walking on heightened surfaces). RESULTS: Arousal scores increased significantly according to environmental context (natural > built environment) and task complexity (HD > MD > LD). Both groups reported a negative valence for demanding conditions, a positive valence for LD in natural environments, and a neutral valence for LD in built environments. When comparing PD and HS, valence attribution was similar, whereas PD participants reported higher arousal than controls. DISCUSSION: The overall higher arousal levels observed in PD patients compared with HS may reflect a heightened emotional reactivity to walking-related challenges. This study will enhance our understanding of gait-related difficulties in PD.