Study of Tics in Patients With Tourette's Syndrome and Chronic Motor Tic Disorder With [15O]H2O PET in Awake and in Sleep States

This study will investigate which areas of the brain are primarily involved in and responsible for tics in patients with Tourette's syndrome and chronic motor disorder. Tourette's syndrome is a neuropsychiatric disorder characterized by motor and vocal tics and is associated with behavioral and emotional disturbances, including symptoms of attention deficit hyperactivity disorder and obsessive-compulsive disorder. Chronic motor disorder has the same characteristics as Tourette's syndrome, except that patients do not have vocal tics.

Healthy normal volunteers and patients with Tourette's syndrome or chronic motor tic disorder between 18 and 65 years of age may be eligible for this study. Candidates will be screened with a medical history and physical and neurological examinations.

Participants will undergo positron emission tomography (PET) scanning to study tics under three conditions- spontaneous tics, suppression of tics, and sleep-to determine which areas of the brain are responsible for generation of tics. For this procedure, the subject is injected with H215O, a radioactive substance similar to water. A special camera detects the radiation emitted by the H215O, allowing measurement of brain blood flow. Subjects will receive up to 20 injections of H215O during the scanning.

Participants will be asked not to sleep the entire night before the test. Before the scan, both patients and volunteers will have EEG electrodes placed on their heads to record the electrical activity of their brains. Patients will also have EMG electrodes placed in areas of the body where tics occur. A small catheter (plastic tube) will be placed in an arm vein for injecting the radioactive tracers, and a mask will be placed on the face to help keep the head still during scanning. The mask has large openings for eyes, nose and mouth, so that it does not interfere with talking or breathing. The entire test takes about 4 hours. During this time, the subject will sleep for 1.5 hours either at the beginning or end of the scan. For the other 2.5 hours, scans will be done every 10 minutes for 1 minute under the different conditions of tic suppression or release of tics.

On a separate day, participants will also undergo magnetic resonance imaging (MRI), a diagnostic test that uses a magnetic field and radio waves to produce images of the brain. For this procedure, the subject lies still on a stretcher that is moved into the scanner (a narrow cylinder containing the magnet). ...