Long-Term Motor Learning in Focal Hand Dystonia

This study will examine the effects of long-term practice of repeated finger movements in people with focal hand dystonia, as compared with healthy volunteers. Patients with dystonia have muscle spasms that cause abnormal postures while trying to perform a movement. In focal dystonia, just one part of the body, such as the hand, neck or face, is involved. Right-handed healthy volunteers and patients with focal hand dystonia of the right hand 18 years of age and older may be eligible for this study. Candidates are screened with a medical history and neurological and physical examination. Participants are trained daily for 11 days (excluding weekends) at the NIH and are asked to continue with daily 15 minutes of practice over a 12-week period to perform sequential finger movement task (key presses) with their left hand. They practice initially at NIH and then at home. At each clinic visit, their learning of the motor skill is assessed by recording their performance of 20 consecutive trials of the eight sequences (a total of 160 key presses) in the task. To evaluate long-term motor learning of the sequential movements, participants are asked to do different task tests at Day 2, Week 4 and Week 12. Brain wave activity, and brain excitability are also measured during these days. In one task, they see a random series of letters on a screen during the sequential finger movements and are asked to say the number of times they see a specific letter. In another task, they are asked to focus on each specific movement while performing the sequential finger movements. During each visit, they are questioned and evaluated for the development of any abnormal movements that may be suggestive of early dystonia. All participants have an electroencephalogram (EEG) and transcranial magnetic stimulation (TMS) at Day 1, and Day 2 and at Week 4 and Week 12 to evaluate brain activity. For the EEG, electrodes are placed on the subject's scalp and the electrical activity of the brain is re