Clinical Trial: The Effects of Repetitive Paired Associative Stimulation in Dystonia

Study Status: Completed
Recruit Status: Completed
Study Type: Observational

Official Title: Investigating the Plastic Effects of Repetitive Paired Associative Stimulation (rPAS) in Dystonia

Brief Summary:

Background:

- People with dystonia have serious muscle contractions that cause abnormal movements or postures. This significantly affects their daily lives. The common type is called organic. The other type is psychogenic. People with this type have typical symptoms plus some psychological effects. Researchers will look at how rapid transcranial magnetic stimulation (rTMS) of the brain combined with stimulation of a nerve affects the ability to detect sensations. They will compare the responses of people with different types of dystonia. They will also compare the responses of people with dystonia to responses of people without it. This study may help us learn more about the nature of different types of dystonia.

Objectives:

- To see whether TMS combined with nerve stimulation affects the brain differently in people with different types of dystonia and those without dystonia.

Eligibility:

  • Individuals at least 18 years old, who are right-handed and have dystonia.
  • Healthy volunteers at least 18 years old.

Design:

  • Participants will have two clinical visits. Each visit will be a few hours long. They can be done on the same day.
  • Participants will be screened with a medical history and physical exam.
  • Participants will take several sensory tests. For these tests, electrodes will be placed on their skin. The participants will feel small electric shocks during some of the tests.

  • Detailed Summary:

    Objective:

    To investigate the effects of pairing brain and peripheral nerve stimulation in organic and psychogenic dystonia to see if this technique can differentiate them.

    Study Population:

    We intend to do an internal pilot study of 6 patients with organic dystonia, 6 patients with clinically definite psychogenic dystonia and 6 age-matched healthy volunteers. We will then perform an analysis to see how many subjects we need to prove or disprove a difference between groups.

    Design:

    Subjects will have a baseline screening visit, electromyography (EMG) and nerve stimulation, sensory threshold testing, and measurements of brain excitability using motor evoked potentials (MEPs) from transcranial magnetic stimulation (TMS). They will then undergo rapid TMS repetitively paired with stimulation of a nerve in the arm. Outcome variables will again be measured immediately after (T0), 30 minutes (T30) after, and 60 minutes (T60) after the end of brain stimulation.

    Outcome Measures

    Primary outcome variable: Change in MEP amplitudes at T30 from baseline

    Secondary outcome variables:

    • Input-output curve parameters (measured at baseline, T0, T30, and T60)
    • Temporal discrimination threshold (TDT)

    Exploratory Measures

    • Short interval intracortical inhibition (SICI), a measure of inhibition in the m
      Sponsor: National Institute of Neurological Disorders and Stroke (NINDS)

      Current Primary Outcome: Change from baseline in the motor evoked potential (MEP) amplitude at S50 after 30 minutes from rPAS (T30). [ Time Frame: 30 minutes from rPAS ]

      Original Primary Outcome: Same as current

      Current Secondary Outcome:

      Original Secondary Outcome:

      Information By: National Institutes of Health Clinical Center (CC)

      Dates:
      Date Received: June 26, 2013
      Date Started: June 18, 2013
      Date Completion:
      Last Updated: April 19, 2017
      Last Verified: August 2, 2016