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).
- INCLUSION CRITERIA: - Age 18 years or older - Able to provide informed consent - Clinical diagnosis of Parkinson disease by U.K. Parkinson Society Brain Bank Criteria - Patients must be stage II -III on the Hoehn and Yahr scale EXCLUSION CRITERIA: - MoCA<25 within the last 6 months - Uncontrolled medical condition requiring immediate treatment that would make a walking trial unsafe for the subject. - Peripheral neuropathy that severely limits gait - Current or recent orthopedic disorder that severely limits gait - Current uncontrolled depression or major depressive episode - Gait disorders other than PD. - Cannot walk safely without corrective lenses and without support. - Unable to abstain from PD medications overnight for at least 12 hours before testing - History of deep brain stimulation surgery - Subjects who are NINDS employees - In addition to the preceding criteria, healthy volunteers must also have a normal neurological examination performed within the last year. Healthy volunteers will be healthy subjects without any major medical and neurological or psychiatric disorders established by history and physical/neurological examination. They will also have no gait disorders from any medical or surgical problems as per clinical assessment.