The main purpose of the studies presented in this protocol is to investigate the physiology of motor control in health as well as the pathophysiological modifications taking place during disease. Patients and normal volunteers will be scanned at rest and during different tasks, either while making repetitive movements or undergoing sensory stimulation. These studies should provide new insight concerning the processes that control human movement and sensory processing. The studies described in this protocol will be conducted by systems operating on 1.5 Tesla up to 4 Tesla, including a system at 3 Tesla which is going to be installed in near future.