Transspinal-Transcortical Paired Stimulation for Neuroplasticity and Recovery After SCI

People with spinal cord injury (SCI) have motor dysfunction that results in substantial social, personal, and economic costs. Uncontrolled muscle spasticity and motor dysfunction result in disabilities that significantly reduce quality of life. Several rehabilitation interventions are utilized to treat muscle spasticity and motor dysfunction after SCI in humans. However, because most interventions rely on sensory afferent feedback that is interpreted by malfunctioned neuronal networks, rehabilitation efforts are greatly compromised. On the other hand, changes in the function of nerve cells connecting the brain and spinal cord have been reported following repetitive electromagnetic stimulation delivered over the head and legs or arms at specific time intervals. In addition, evidence suggests that electrical signals delivered to the spinal cord can regenerate spinal motor neurons in injured animals. A fundamental knowledge gap still exists on neuroplasticity and recovery of leg motor function in people with SCI after repetitive transspinal cord and transcortical stimulation. In this project, it is proposed that repetitive pairing of transspinal cord stimulation with transcortical stimulation strengthens the connections between the brain and spinal cord, decreases ankle spasticity, and improves leg movement. People with motor incomplete SCI will receive transspinal - transcortical paired associative stimulation at rest and during assisted stepping. The effects of this novel neuromodulation paradigm will be established via clinical tests and noninvasive neurophysiological methods that assess the pathways connecting the brain with the spinal cord.