Study of Tics in Patients With Tourette's Syndrome and Chronic Motor Tic Disorder
Condition: Tourette Syndrome; Tic Disorders
MeSH terms: Tourette Syndrome; Tics; Tic Disorders; Syndrome
Study type: Observational

Summary: 
      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). ...
    

Detailed description: 
      The purpose of this study is to determine the areas of the brain responsible for tics in
      patients with Tourette's syndrome and chronic motor tic disorder using [15O]H2O. Previous
      neuroimaging studies have looked at brain activity during tics using functional magnetic
      resonance imaging (fMRI), and positron emission tomography (PET), but a major drawback of
      these studies lay in the difficulty distinguishing between the activity in the brain
      responsible for tic generation versus activity in motor-related structures due to tic
      movements. We plan to overcome this difficulty in our paradigm using two rest conditions
      without any movement. One is a state when patients suppress their tics and the second is
      sleep state, when tics usually cease or are at least very infrequent. 23 adult patients with
      a DSM-IV-TR (American Psychiatric Association 2000) diagnosis of a tic disorder and frequent
      tics will be studied. These two rest states will be compared with a condition where tics are
      allowed to occur spontaneously. The differential activation of brain areas between these
      three conditions should help to elucidate/define the regions of the brain responsible for
      generation of tics.
    

Keywords: Tics; Basal Ganglia; Neuroimaging; Sleep; Suppression of Tics; Tourette Syndrome; Tourette's Syndrome; Tic Disorder; Healthy Volunteer; HV; Normal Control