Grant: Doctoral: Vanier Canada Graduate Scholarships

A study by the Christopher & Dana Reeve Foundation in the US reported that 1 in 50 people live with paralysis in North America (~ 6 million people), with spinal cord injury (SCI) being the leading cause for paralysis. Restoring standing and walking after paralyzing injuries or diseases has been a central research and clinical goal. A novel approach developed in our lab, called intraspinal microstimulation (ISMS), has been shown to produce robust standing and functional walking of the paralyzed hind limbs in animal experiments. This method involves the implantation of very fine, hair-like wires, in a small region of the spinal cord. Minute levels of electrical current are passed through these wires to activate existing networks in the spinal cord that produce standing and walking movements. As part of my PhD work, I will use non-invasive magnetic resonance imaging (MRI) techniques to determine the distribution of the networks involved in standing and walking in the spinal cord of humans. My work will lead, for the first time, to the understanding of the organization of locomotor networks in the spinal cord of humans. I will use this knowledge to advance ISMS towards clinical implementation. My experiments will involve able-bodied volunteers and volunteers with spinal cord injury. Contractions in individual muscles in the legs will be elicited through non-invasive electrical stimulation during MRI scanning. The distribution of the locomotor networks in the lumbosacral spinal cord that coordinate the activity of the muscles in the legs will be identified. The study will then be extended to investigate more complex muscle activation patterns such as synergistic activation of multiple muscles and rhythmic activation of muscles as seen during natural walking. My work will have a substantial impact on the fields of neuroscience and rehabilitation. It will also facilitate the implementation of promising interventions, such as ISMS, for restoring standing and walking.