Brain Stimulation and Tailored Interventions to Promote Recovery in Stroke Survivors

A substantial proportion of individuals are left with poor residual functioning of the affected arm after a stroke. This has a tremendous impact on the quality of life and the ability for stroke survivors to live independently. While exercise is considered essential to any rehabilitation program, its benefits are generally far from optimal because of the lack of proper dosing in terms of intensity. One way to tackle this problem is to develop better tools that could predict an individual's potential and then adjust the intensity of exercise accordingly. One such predicting tool exists and consists of using non-invasive brain stimulation such as transcranial magnetic stimulation (TMS), to assess the integrity of descending motor pathways originating from the brain. TMS consists of applying a magnetic wand near the scalp to stimulate brain cells without inducing pain or discomfort. One goal of the current proposal is to use TMS to test the integrity of the motor pathway in chronic stroke survivors. The level of responses to TMS will be used to classify participants in terms of potential for recovery and then, to determine the optimal level of exercise. The study will also examine the effect of another non-invasive brain stimulation technique called transcranial Direct-Current Stimulation-tDCS to determine whether it can enhance the response to strength training exercise in the affected arm. Half of the participants will be trained with the tDCS on, while the other half will be trained with the stimulator off. The training program will last 4 weeks; 3X/week. Both clinical and neurophysiological measures will be performed to determine the impact of the strength training intervention on participants. Overall, the proposed project is expected to have a positive and significant impact on stroke survivors' quality of life.