Behavioral and Neural Effects of Bihemispheric Brain Stimulation on Stroke Recovery

Newswise — Researchers in the Neuroimaging and Stroke Recovery Laboratory at Beth Israel Deaconess Medical Center / Harvard Medical School are using a novel treatment for chronic stroke patients. The non-invasive technique of dual-hemisphere transcranial direct current stimulation (tDCS) uses electrical stimulation to modulate brain activity while simultaneous engaging the paretic arm/hand in sensorimotor activities. They studied chronic stroke patients who had movement problems after a stroke in a randomized clinical trial. The patients were divided into groups receiving either the electrical stimulation or placebo stimulation while receiving occupational therapy (OT) at the same time. After only 5 treatment sessions, patients receiving real stimulation and OT significantly improved in their motor functions, while control patients (receiving placebo stimulation and OT) showed no significant improvement. Functional magnetic resonance imaging showed increased brain activity in areas that control limb movement on the affected side for patients who received the real tDCS. It is important to notice that these changes were found in patients whose strokes had occurred on average about 3 years prior to the study, when patients are typically considered to be stable and unlikely to experience further improvement. This new treatment offers hope for patients debilitated by strokes.

Authors: R Lindenberg, LL Zhu, V Renga, D Nair, G Schlaug, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States