The first step of our experimental approach will consist in studying the kinematics and EMG patterns of movements performed by the different groups of patients. For studying motor control of the upper limb, we will ask the patients to perform both wrist movements in isolation, or in association with a superimposed motor, cognitive or emotional task. The organisation and abnormalities of movements of the lower limb will be studied following the same rationale, whenever possible. Because of the occurrence of involuntary movements in many patients with dystonia, all behavioural recordings will be performed using telemetric equipment. This will guarantee that patients will not pull off the captors, nor run any risk of getting hurt during the recording sessions.