fMRI Studies of Task Specificity in Focal Hand Dystonia
fMRI Studies of Task Specificity in Focal Hand Dystonia
This study will examine how the brain makes involuntary spasms and contractions in patients
 with focal hand dystonia (FHD). Patients with dystonia have muscle spasms that cause
 uncontrolled twisting and repetitive movement or abnormal postures. In FHD, only the hand is
 involved. The study will use functional magnetic resonance imaging (fMRI, see below) to study
 which areas of the brain are primarily affected in FHD and better understand how brain
 changes produce dystonia symptoms.

 Normal right-handed volunteers and patients with FHD who are 18-65 years of age may be
 eligible for this study. Candidates are screened with a medical history and physical and
 neurological examinations. Women who can become pregnant have a urine pregnancy test.

 All participants undergo fMRI. This test uses a strong magnetic field and radio waves to
 obtain images of body organs and tissues. The subject lies on a table that is moved into the
 scanner (a metal cylinder), wearing earplugs to muffle loud knocking and thumping sounds that
 occur during the scanning process. The procedure lasts about 90 minutes, during which time
 the patient is asked to lie still for 10-15 minutes at a time. During the procedure, subjects
 are asked to perform some tasks, including writing, tapping with their hand, and drawing in a
 zigzag motion. Each task is performed using the right hand, left hand and right foot.
Objective:

 Writer's cramp, a form of focal hand dystonia, is the most frequently observed task specific
 dystonia. Symptoms of writer's cramp often appear as soon as the pen is picked up, or after a
 few words of writing. Patients with simple writer's cramp have difficulties writing, but
 carry out other tasks with the affected hand without spasms. Little is known about why the
 hand spasms when writing, while performing other tasks normally.

 The purpose of this study is to identify brain areas of activation associated specifically
 with the task of handwriting with the dystonic hand, in patients with simple writer's cramp.
 Simple writer's cramp can be defined by a patient exhibiting the symptoms only when writing
 and symptoms are not present in any other task performance. Specifically for this study,
 patients should be able to write for 20 seconds consecutively in a run. We plan to use
 functional magnetic resonance imaging (fMRI) to identify the pattern of blood oxygenation
 level-dependent (BOLD) activation in the brain when different tasks are performed by
 different limbs in healthy volunteers and patients with focal hand dystonia.

 Study Population:

 This research will be conducted using 22 patients diagnosed with simple writer's cramp and 32
 healthy volunteers matched for age and gender.

 Design:

 Using a block design in functional magnetic resonance imaging (fMRI), we will examine the
 brain activity of patients and healthy volunteers while they execute three tasks: writing,
 tapping and a zigzagging motion, with three separate limbs: the dystonic hand, the opposite
 hand, and the right foot.

 Outcome Measures:

 The changes in signal intensity of the brain activity correlated with the motor program (task
 of handwriting) and effector (dystonic hand) will be collected and analyzed.

 The findings we expect to obtain with this experiment may contribute to basic knowledge of
 the linkage between task specificity and the dystonic hand, and may provide a better
 understanding of the pathophysiology of writer's cramp.
-  INCLUSION CRITERIA:

 Focal Dystonia Subjects must be:

 -  Right hand dominant

 -  Between 18 and 65 years old

 -  Diagnosed with mild, simple focal hand dystonia. For this study mild, simple focal
 hand dystonia suggests that the patient does not present symptoms when performing
 tasks other than writing. Additionally, the patient should be able to write for 20
 seconds consecutively

 -  Willing to abstain from alcohol 48 hours prior to the study

 Volunteers must be:

 -  Healthy right-handed dominant individuals

 -  Between 18 and 65 years old

 -  Willing to abstain from alcohol 48 hours prior to the study

 EXCLUSION CRITERIA:

 -  Subjects with implanted devices such as pacemakers, medication pumps or
 defibrillators, metal in the cranium except mouth, intracardiac lines, history of
 shrapnel injury or any other condition/device that may be contraindicated or prevent
 the acquisition of MRI

 -  Subjects with any finding on the MRI safety questionnaire which prevents them from
 safely undergoing an MRI scan

 -  Subjects who are pregnant.

 -  Subjects with claustrophobia or other restrictions which prevent them from undergoing
 a scan in a confined space for up to 60 minutes

 -  Subjects with any visual, motor, or hearing difficulties

 -  Subjects with severe focal hand dystonia i.e., subjects who experience dystonic spasms
 in tasks other than/in addition to writing

 -  Subjects with mirror dystonia

 -  Subjects without the capacity to give consent

 -  Subjects with any history of a severe medical condition, such as cardiovascular
 disease, which will prevent them from lying flat for up to 60 minutes.

 -  Subjects with any history of brain tumor, stroke, head trauma or vascular malformation
 as obtained by history or from imaging studies.

 -  Subjects who have had recent (within 3 months) Botulinum Toxin (Botox) injections.

 -  Subjects who are on anti-parkinsonian drugs