The National Institute of Neurological Disorders and Stroke, part of the National Institutes of Health, is looking for individuals to participate in clinical studies. Participating in clinical trials allows you to play an active role in research on the nature and causes of many disorders of the brain and nervous system, and to possibly help physician-scientists develop future treatments. The information below is designed to help you quickly learn about actively recruiting research studies for which you or someone you know may be eligible.


The purpose of this study is to investigate the physiology associated with plasticity of the motor system seen in a number of different circumstances. Techniques used will involve the combination of transcranial magnetic stimulation (TMS) and pharmacologic interventions. We propose to use drugs judged to be safe, that either potentiate GABA related intracortical inhibition, change presynaptic release of excitatory aminoacids like glutamate, or decrease the activity of the NMDA receptors (mostly antiepileptic drugs). If plastic changes expressed as larger motor maps or motor evoked potentials (MEP) to TMS are secondary to intracortical disinhibition, administration of a drug that potentiates intracortical inhibition may result in decreased plasticity and smaller motor maps or MEP. This finding would then identify intracortical disinhibition as the mechanism responsible for this type of plasticity. Similarly, if plastic changes decrease with a drug that inhibits release of excitatory aminoacids, or that antagonize the action of NMDA receptors, the mechanism underlying plasticity is likely to be mediated by modulation in the release of excitatory aminoacids or activity in NMDA-receptors. Results from this study will then provide information about the relative involvement of intracortical disinhibition, modulation in the release of excitatory aminoacids, and role of NMDA receptors in different settings of human plasticity.

Eligibility Criteria:

Must be over 18 years of age. Must not have personal history of seizures, loss of consciousness, hypertension, psychosis, heart conditions or allergies to any of the drugs. Women must not be nursing or pregnant. Patients may have amputations, spinal cord injuries, blindness or large hemispheric lesions from stroke.

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