Enhancing Plasticity in Stroke Patients With Severe Motor Deficit

Enhancing Cortical Plasticity With Nerve Stimulation in Stroke Patients With Severe Motor Deficit

This study will evaluate the effectiveness of sustained peripheral nerve stimulation coupled with functional motor training, to improve hand motor function in poorly recovered stroke patients. The central hypothesis is that stroke patients with severe motor deficit receiving hand nerve stimulation and intensive task-oriented therapy will have improved motor function compared to patients receiving sham nerve stimulation and task-oriented therapy.

Stroke is one of the most devastating and prevalent diseases, but efforts to limit the amount of tissue damaged in the acute phase have been disappointing, highlighting the need for effective therapeutic interventions after neurologic damage has occurred. Data from animal and human models have suggested that sensory input plays an important role in motor output, possibly by influencing cortical plasticity. However, in spite of the advances to date, little is known about the extent to which sensory input in the form of peripheral nerve stimulation can be successfully combined to physical training especially in poorly recovered stroke patients. This study will evaluate the effectiveness of sustained peripheral nerve stimulation coupled with functional motor training, to improve hand motor function in stroke patients with severe motor deficit. The central hypothesis is that stroke patients with severe motor deficit receiving hand nerve stimulation and intensive task-oriented therapy will have improved motor function compared to patients receiving sham nerve stimulation and task-oriented therapy, and the degree of this behaviorally-measured effect will correlate with the neurophysiological effect measured by transcranial magnetic stimulation.

Inclusion Criteria:

• Chronic stroke patients
• Single stroke
• Chronic (more than 12 months after from stroke)
• At least 21 years old, but there is no upper age range for this project.
• Participants NOT able to extend the affected metacarpophalangeal joints at least 10° and the wrist 20°.

Exclusion Criteria:

• History of carpal tunnel syndrome and conditions that commonly cause peripheral neuropathy, including diabetes, uremia, or associated nutritional deficiencies
• History of head injury with loss of consciousness, severe alcohol or drug abuse, psychiatric illness
• Within 3 months of recruitment, use of drugs known to exert detrimental effects on motor recovery
• Cognitive deficit severe enough to preclude informed consent
• Positive pregnancy test or being of childbearing age and not using appropriate contraception
• Participants with history of untreated depression.