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Transcranial Magnetic Stimulation and Electrical Stimulation of Nerves to Study Focal Dystonia

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00050024
Recruitment Status : Completed
First Posted : November 20, 2002
Last Update Posted : July 2, 2017
Information provided by:
National Institutes of Health Clinical Center (CC)

Tracking Information
First Submitted Date November 19, 2002
First Posted Date November 20, 2002
Last Update Posted Date July 2, 2017
Study Start Date November 13, 2002
Primary Completion Date Not Provided
Current Primary Outcome Measures Not Provided
Original Primary Outcome Measures Not Provided
Change History
Current Secondary Outcome Measures Not Provided
Original Secondary Outcome Measures Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title Transcranial Magnetic Stimulation and Electrical Stimulation of Nerves to Study Focal Dystonia
Official Title The Effect of Peripheral Heterotopic Stimulation on Cortical Excitability in Dystonia
Brief Summary

This study will use transcranial magnetic stimulation (TMS) and electrical stimulation of nerves to examine how the brain controls muscle movement in focal hand dystonia (writer's cramp). Normally, when a person moves a finger, the brain's motor cortex prevents the other fingers from moving involuntarily. Patients with focal hand dystonia have difficulty with individualized finger movements, possibly due to increased excitability of the motor cortex. Musicians, writers, typists, athletes and others whose work involves frequent repetitive movements may develop focal dystonia of the hand.

Healthy normal volunteers and patients with focal dystonia 18 years of age and older may be eligible for this study.

For the TMS procedure, subjects are seated in a comfortable chair with their hands placed on a pillow on their lap. An insulated wire coil is placed on the scalp. A brief electrical current is passed through the coil, creating a magnetic pulse that stimulates the brain. This may cause muscle, hand or arm twitching if the coil is near the part of the brain that controls movement, or it may induce twitches or transient tingling in the forearm, head or face muscles. Subjects will be asked to move a finger. Just before this movement, a brief electrical stimulation will be applied to the end of either the second or fifth finger. Metal electrodes will be taped to the skin over the muscle for computer recording of the electrical activity of the hand and arm muscles activated by the stimulation. The testing will last 2-3 hours.


Detailed Description The purpose of this study is to investigate the effect of sensory afferent input on surround inhibition in the motor cortex in dystonia. Surround inhibition is a cortical phenomenon, the function of which may be to suppress unwanted movements in surrounding muscles during voluntary actions. In support of this, a recent study showed that motor output to the little finger was reduced during self-paced, voluntary movements of the index finger, despite an increase in spinal excitability. Work has also shown that in relaxed muscles, homotopic and heterotopic peripheral stimulation results in time dependent modulation of motor cortical excitability. However, no studies have examined the relationship between volitional movement and sensory input on cortical surround inhibition, the phenomenon which we hypothesize to be defective in dystonia. The aim of this study then is to examine the changes in surround inhibition when electrical stimulation is applied to the finger being actively moved, leading to an inhibition of a surrounding finger (heterotopic inhibition), at different time intervals prior to the initiation of movement, to assess the effect of heterotopic peripheral stimulation on surround inhibition in dystonia patients compared to normal subjects.
Study Type Observational
Study Design Not Provided
Target Follow-Up Duration Not Provided
Biospecimen Not Provided
Sampling Method Not Provided
Study Population Not Provided
Condition Dystonic Disorders
Intervention Not Provided
Study Groups/Cohorts Not Provided
Publications *

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status Completed
 (submitted: June¬†23,¬†2005)
Original Enrollment Same as current
Study Completion Date September 17, 2008
Primary Completion Date Not Provided
Eligibility Criteria

Nineteen patients age 18 and over with focal dystonia of the upper limbs (writer's cramp) will be recruited for the study.

For patients, the only selection criteria are the presence of focal hand dystonia.

Nineteen normal subjects age 18 and over will be recruited for the control group.

The controls will not have dystonia or any other neurological condition.

All subjects will sign an informed consent prior to participation in the trial.


Exclusion criteria for the trial covering both the normal control and dystonia group will include any concurrent medical or surgical condition as well as neurological or psychiatric illnesses.

Exclusion criteria will include any individual who is on medications with potential influence of the nervous system function (antidepressants, anxiolytics, anticonvulsants, antipsychotic, antiparkinson, hypnotics, stimulants, and antihistamines).

The exclusion criteria also include patients who have received Botulinum toxin injection within 3 months of starting the protocol.

Furthermore, any individual who has a pacemaker, an implanted medical pump, a metal plate or metal object in the skull or eye (for example, after brain surgery), or who has a history of seizure disorder will be excluded from the trial.

Sexes Eligible for Study: All
Ages 18 Years and older   (Adult, Older Adult)
Accepts Healthy Volunteers No
Contacts Contact information is only displayed when the study is recruiting subjects
Listed Location Countries United States
Removed Location Countries  
Administrative Information
NCT Number NCT00050024
Other Study ID Numbers 030048
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement Not Provided
Responsible Party Not Provided
Study Sponsor National Institute of Neurological Disorders and Stroke (NINDS)
Collaborators Not Provided
Investigators Not Provided
PRS Account National Institutes of Health Clinical Center (CC)
Verification Date September 17, 2008