Physiology of Weakness in Movement Disorders

Objective Give way weakness is a symptom often associated with psychogenic etiology, but its neurophysiological basis is poorly understood. Our objective in this study is to identify the cerebral mechanism of give way weakness. Study population We will study 6 patients with give way weakness and 6 healthy volunteers all age 18 years old or older. Design In this study, patients will try to resist against the examiner's force and subsequently give way. Electroencephalography (EEG) will be recorded while this maneuver is performed repeatedly. Outcome measures Movement-related cortical potential (MRCP) analysis will be performed on the data and its amplitude (in volts) and latency (in seconds) in each individual patient will be described in contrast to the data obtained from healthy volunteers.