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EEG and EMG Studies of Hand Dystonia

This study has been completed.
Information provided by:
National Institutes of Health Clinical Center (CC) Identifier:
First received: October 11, 2001
Last updated: January 24, 2017
Last verified: October 4, 2010

This study will examine how the brain operates during execution and control of voluntary movement and what goes wrong with these processes in disease. It will use electroencephalography (EEG) and electromyography (EMG) to compare brain function in normal subjects and in patients with focal hand dystonia. In dystonia, involuntary muscle movements, or spasms, cause uncontrolled twisting and repetitive movement or abnormal postures. Focal dystonia involves just one region of the body, such as the hand, neck or face.

EEG measures the electrical activity of the brain. The activity is recorded using wire electrodes attached to the scalp or mounted on a Lycra cap placed on the head. EMG measures electrical activity from muscles. It uses wire electrodes placed on the skin over the muscles.

Adult healthy normal volunteers and patients with focal hand dystonia may be eligible for this study. Patients will be selected from NINDS's dystonia patient database.

Participants will sit in a semi-reclining chair in a darkened room and be asked to move either their right index finger, right foot, or the angle of their mouth on the right side at a rate of one movement every 10 seconds. Brain and muscle activity will be measured during this task with EEG and EMG recordings.

Focal Dystonia

Study Type: Observational
Official Title: EEG Study of Movement-Related Center-Surround Organization in Hand Dystonia

Resource links provided by NLM:

Further study details as provided by National Institutes of Health Clinical Center (CC):

Enrollment: 75
Study Start Date: October 9, 2001
Estimated Study Completion Date: October 4, 2010
Detailed Description:


  • To find and quantify EEG/MEG correlates of cortical center-surround organization and intracortical inhibition.
  • To compare these between healthy volunteers and focal hand dystonia (FHD) patients.

Study Population

- Healthy volunteers and FHD patients.


- The study has two separate arms aiming to examine the same question. In the first one subjects perform a 4-choice contingence negative variation (CNT) type motor task while multi-channel EEG and EMG are recorded. In the second arm somatosensory evoked potentials (SEPs) or fields (SEFs) are recorded to median nerve stimulation.

Outcome Measures

- First arm: EEG band-power difference between "center" and "surround". Second arm: number, amplitude, and power of high frequency oscillations (HFOs) component of SEPs/SEFs.


Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

The study population will consist of (a) healthy volunteers; and (b) patients with focal hand dystonia.

Healthy subjects: Healthy volunteers who consented to participate in the study.

Patients diagnosed with focal hand dystonia: unilateral focal hand dystonia from our dystonia patient database who consented to participate in the study.


Healthy subjects: abnormal neurological exam or history of past neurological disease.

Dystonia patients: the presence of a second neurological disease or condition; abnormal neurological findings on exam that are not related to their focal hand dystonia.

For MRI studies, patients with metallic implants will be excluded to remove potential risks from this procedure.

For MRI purposes, women who are pregnant are excluded from this part of the protocol. Therefore, all women of childbearing potential will have a pregnancy test performed prior to prospective MRI studies, which must be negative, before proceeding.

For TMS studies, healthy volunteers or focal hand dystonia patients who have a pacemaker, an implanted medical pump, a metal plate or metal object in the skull or eye (for example, after brain surgery), or who have a history of seizure disorder will be excluded from the trial.

  Contacts and Locations
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Please refer to this study by its identifier: NCT00025701

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institute of Neurological Disorders and Stroke (NINDS)
  More Information

Publications: Identifier: NCT00025701     History of Changes
Other Study ID Numbers: 020010
Study First Received: October 11, 2001
Last Updated: January 24, 2017

Keywords provided by National Institutes of Health Clinical Center (CC):
Motor Control
Event-Related Synchronization
Event-Related Desynchronization
Focal Hand Dystonia
Focal Dystonia
Healthy Volunteer

Additional relevant MeSH terms:
Dystonic Disorders
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Movement Disorders
Central Nervous System Diseases processed this record on April 28, 2017