Project 462609

After stroke, many patients have problems using their hand. Despite advances, rehabilitation is often only partially effective. One promising approach to augment recovery is to use electrodes implanted into the brain to precisely activate dormant circuits important for recovery. This exciting technology acts like a prosthesis to help heal the injured brain. To be effective the prosthesis must be individually adapted because each stroke is different. However, choosing the most effective stimulation is a complex problem. To solve it, we created a computer program that uses artificial intelligence to find the best parameters of stimulation automatically and rapidly. We will use this tool to develop a new brain prosthesis that facilitates recovery of hand movements after stroke. Our experiments will be conducted in rats that have strokes similar in severity and extent to those in humans. We will put electrodes in healthy tissue around the stroke, in brain regions that control movements. Our first objective is to adapt the computer program to assist arm and hand movements after stroke. The brain will be stimulated while the rats perform reaching and grasping movements to obtain food rewards. We will identify the most effective stimulation strategy to augment recovery. Second, we will study the effects of stimulation alone, and in combination with rehabilitation therapy, on post-stroke recovery. We will compare the efficacy of the treatment when delivered at different times after stroke. Our third objective is to study the effect of the new prosthesis on brain circuits. This will help us identify ways we could further improve our technology. Knowledge generated from this grant will allow us to make a brain prosthesis individually adapted to each stroke and that can adjust itself as the brain changes during recovery. The technology we propose to develop could help people recover much more completely after stroke and may also benefit people with other brain diseases.