Driving Neuroplasticity with Nerve Stimulation and Modified Constraint-Induced Therapy

Lumy Sawaki, MD, PhD, University of Kentucky, Physical Medicine & Rehabilitation Department, Cardinal Hill Endowed Chair

We propose to evaluate the effectiveness of sustained peripheral nerve stimulation (PNS) to enhance the therapeutic effects of a modified form CIT (mCIT).

The central hypothesis is that stroke patients receiving hand PNS and mCIT will have improved motor function compared to patients receiving sham PNS and mCIT, and the degree of this behaviorally-measured effect will correlate with the neurophysiological effect measured by TMS. We plan to accept or reject the central hypothesis by accomplishing two Specific Aims.

Specific Aim #1: Test the effect of hand PNS preceding intensive task-oriented therapy, such as mCIT, on hand motor function, measured by the Fugl-Meyer Assessment Scale. The working hypothesis for this aim is:

• Hand PNS paired with mCIT will lead to a higher score on the Fugl-Meyer Assessment Scale, compared to a control stimulation group receiving sham PNS paired with mCIT.

Specific Aim #2: Test the effect of hand PNS preceding intensive task-oriented therapy, such as mCIT, on motor map of a specific muscle (extensor digitorum communis muscle) measured by transcranial magnetic stimulation (TMS). The working hypothesis for this aim is:

• PNS and training of the paretic hand will lead to an increase in TMS motor map of the relevant motor cortex, in a topographically specific manner, compared to a control stimulation group receiving sham PNS.
• The improved hand motor function will yield increased TMS motor map induced by hand PNS compared to a control stimulation group, receiving sham stimulation.