Inside UVic’s Motor control research lab, investigations into such commonplace activities as walking is revealing secrets about the nervous system that may one day improve motor function in people who have suffered stroke or spinal cord injury.
Directing this research is Dr. Paul Zehr of UVic’s school of physical education, armed with nearly $1 million in funding and a desire to advance neurotrauma research at UVic.
Zehr is a leading expert on rhythmic movement. His research in this area over the past few years has focused on how our arms and legs are co-ordinated when we perform such rhythmic motor activities as walking and cycling. His results and the work of others suggest that rhythmic motions are controlled to a large degree by a collection of neurons in the spinal cord called “central pattern generators”or CPGs.
In fact, the spinal cord may play a much larger role in controlling movement than previously thought. This is encouraging news for people who have experienced a neurotrauma injury where communication between the brain and spinal cord is weakened or absent altogether.
“CPGs can be easily started by commands from the brain, but they can also be regulated in part by feedback from movement,” explains Zehr. “For example, when your muscles are being stretched during motion, electrical signals are sent from the muscles back to the spinal cord that reinforce the CPG activity.”
The spinal cord operates differently when it doesn’t have direct input from the brain, and Zehr is hoping to take advantage of the capabilities of CPGs to use whatever function is left over after injury.
If feedback can maintain CPG activity, then can it also act as a surrogate for brain input and help to start CPG activity? To address this question, Zehr plans to conduct experiments in which participants wear special gloves or clothing that increase the electrical feedback signal to the CPGs while they’re performing rhythmic activities. The idea is that artiﬁcially enhancing this signal may help to compensate for the reduced signals from the brain.
Zehr is hopeful that this line of inquiry will yield some positive results.
“Feedback can help do it,” he says, “although it may not be enough in the complete absence of brain input. But with incomplete injuries, there’s still a little bit of input from the brain that can help jazz things up, so combined with feedback you can hopefully get things working.”
If the technique works, it could be the basis for more effective Rehabilitation therapies for people with neurotrauma.
Funding for Zehr’s research and lab operation costs comes from the Christopher Reeve Paralysis Foundation, the Heart and Stroke Foundation of Canada, the Michael Smith Foundation for Health Research, and the Natural Sciences and Engineering Research Council.