The role of visual information on obstacle circumvention during walking in people with Parkinson's Disease under and without dopaminergic medication effects

Abstract

Visual information is essential during locomotion, especially in environments that present obstacles, which is similar our day by day. The sensory and perceptual processing are used to assess obstacles ahead during walking. Sensory and perceptual deficits have recently been identified in people with Parkinson's disease (PD), which have an important contribution to movement disorder. However, how sensory-perceptual function of the basal ganglia affects the control of movement, especially related to dopaminergic medication, have received little attention. The aim of this study is to investigate the role of visual information on circumvention an obstacle circumvention during walking in people with PD and neurologically healthy people. In addition, the influence of dopaminergic medication in sensory-motor integration in people with PD while circumvention an obstacle during walking will be studied. Fifteen people with PD and 15 neurologically healthy people will participate in the study. The participants will perform 5 trials of following conditions: walk without the presence of obstacles and walk with circumvention an obstacle positioned to 5 m, 3 m, 1.5 m and 0.8 m from the start point. We will analyze the visual parameters, the spatiotemporal parameters of walking, the center of mass, the feet positioning strategy related to obstacle and the personal space. People with PD and neurologically healthy people will carry out the tasks in two moments: "ON" and "OFF" state of dopaminergic medication, and before and after placebo ingestion, respectively. The parameters of interest will be compared by ANOVAs three-way (group x medication state x condition) with repeated measures for medication status and condition.