Gait Disorders in Parkinson's Disease

The objective of this protocol is to study the physiology of gait disorders in Parkinson s disease as well as to test the effect of non-invasive interventions on gait function in patients with Parkinson s disease. To this end, this protocol will consist of two sub studies: 1. Sub Study 1: Physiology of Freezing of Gait in Parkinson Disease (abbrev: Physiology of FOG) 1. Objective: To explore temporospatial gait parameters and joint kinematic patterns in patients with Parkinson disease and freezing of gait. In addition, tracking of eye movements and EEG patterns will also be studied in patients with Parkinson disease and freezing of gait. 2. Study Population: 15 PD patients with freezing of gait, 15 patients without freezing of gait, 15 age and gender matched healthy volunteers 3. Design: Prospective Exploratory study 4. Outcome Measures: Phase variability and coherence of oscillating axial and appendicular components of gait in patients with PD and freezing of gait, visual gaze fixations and saccades during freezing or freezing-like events and when approaching a variable width doorway, EEG patterns during an episode of freezing of gait or freeze-like event. The study will also aim to look at the difference in the phenomenon of FOG in OFF and ON states. 2. Sub Study 2: Effects of Rhythmic Vibratory Cueing to Improve Step Parameters in Parkinson Disease (abbrev. Vibratory Cueing) 1. Objective: To study changes in gait variables of patients with PD by providing rhythmic vibratory stimuli at the ankle on one limb at preset parameters. 2. Study population: 15 patients diagnosed as having Parkinson s Disease, Hoehn and Yahr stage 2-3. 3. Design: Prospective interventional hypothesis testing study. We will evaluate the effects of rhythmic vibratory cueing on gait variables in PD. The effects of vibratory cueing will be tested compared to baseline gait variables and with the use of a magnet (which will be the open label placebo intervention to account to some extent, for the open label design).