Grant: Operating Grant

In Canada, about 86,000 people live with a spinal cord injury (SCI), and more than 4,300 new cases arise every year. For SCI individuals, limitations in sensorimotor activities such as walking and posture severely affect their quality of life. In most cases, patients have an incomplete injury that spares some connections between the brain, which initiates movements, and the spinal circuits, which generate them. This places brain structures with partial connectivity to the spinal cord in a particularly favorable position to compensate for the lost function. Specifically, the motor cortex offers significant and unappreciated opportunities for recovery of walking and is a potential target for treatments. My main goal is study the role of the motor cortex in the recovery of locomotion after incomplete SCI. We will use a well-established rat model of SCI in which hindlimb locomotion is progressively re-expressed over five weeks. While this short time course does not mimic recovery in humans, it facilitates exploration of the underlying biological mechanisms. By combining innovative paradigms to manipulate cortical activity with behavioral, electrophysiological and neuroanatomical techniques, we will study the mechanisms by which the cortex affects the spinal circuits that generate stepping after SCI. We will then tap into these mechanisms to foster and enhance recovery of walking by testing cortical stimulation protocols. Our experiments will provide a comprehensive examination of the role of the motor cortex and the mechanisms through which it influences locomotor recovery after SCI. This proposal has the potential to expand our knowledge on the neural basis of recovery after SCI. Activity-based neurorehabilitation and brain stimulation protocols can be developed to harness cortical activity that may catalyze functional recovery, e.g. walking and posture, following SCI.