Grant: CIHR Fellowship

A stroke is caused by a rapid disruption in blood flow to a certain brain region, thus causing brain cells to die. The burden of this disease is significant. With 50,000 new cases occurring each year it is the leading cause of disability in Canada. One potential way for decreasing the impact of stroke is to develop treatment strategies that enhance the brain's inherent capacity to reorganize and recover some of the lost functions. Recent work suggests that transcranial magnetic brain stimulation (which can be applied non-invasively) can enhance the beneficial effects of rehabilitation by transiently reversing some of the brain abnormalities caused by the stroke. In the current experiments we will use a mouse model of stroke to further optimize brain stimulation parameters and also examine the mechanisms of action for effective brain stimulation. Our experiments will utilize a recently developed technology, which allows for light stimulation delivered to the brain to activate selective brain regions. Using this approach we will first identify the specific brain regions that enhance recovery when stimulated by light. In addition, we will also identify optimal stimulation parameters, such as the timing and duration of stimulation. Lastly, we will evaluate the effects of modulating a specific sub-population of neurons within the brain. This population of cells normally sends out inhibitory messages, acting to keep brain activity in check. A stroke may induce over-activity in these cells, thus producing too much inhibition. We will examine the effects of inhibiting these overactive cells with the hope of improving brain function after a stroke.