Dr. Yang is interested in how the nervous system controls movements in general, and walking in particular. Specific topics include:
1) The neural control walking in humans, and how that control changes after injury to the central nervous system.
2) How can we optimize the retrain of walking in adults with spinal cord injury and young children with perinatal brain injury?
3) How do children learn walking related tasks, and how is that different from adults?
Early, intensive motor training in children with perinatal brain injury
Children who suffer injury to the brain before or around the time of birth live with the deficits of this injury for a life time. Yang is interested in whether early, intensive motor training might reduce these deficits. The work is based on animal studies that show there is a critical period early in life, in which activity/training is most effective. A two-centre, randomized controlled trial is currently underway in Edmonton and Calgary to test this idea.
Learning new walking patterns in young children
Infants can step on a split-belt treadmill with the 2 belts running at different speeds or different directions well before they develop independent walking. Like adults, the infants learn to walk more symmetrically on the split-belts over time. Yang is interested in when this learning first appears, and how it develops in early childhood.
Neural mechanisms underlying the retraining of walking in adults with spinal cord injury
Different types of training methods induce different types of neuroplasticity (i.e., changes in the nervous system). Yang and her collaborators are currently studying how training with powered exoskeletons, such as the ReWalk and Ekso, changes the nervous system and improves function.
Jaynie Yang, PhD, is a graduate student supervisor in the Faculty of Rehabilitation Medicine, the Biomedical Engineering Department, and the Neuroscience & Mental Health Institute.
Dr. Yang currently mentors two graduate students and is available to mentor additional students.
Perinatal (around birth) brain injury is devastating, because it permanantly affects a child for life. Many of these children are later diagnosed with cerebral palsy (CP), the most common cause of physical disability in children, of which approximately 70% have walking problems that often require surgery and bracing. The abnormal walking predisposes them to premature arthritis and joint deformities, often requiring further surgery. Recent studies in animals have shown that weakened brain pathways can be strengthened through intensive training at an early, critical period when the developing nervous system is most plastic, thereby restoring lost motor function. Surprisingly, intensive motor training during a critical period of nervous system development (estimated to be < 2 yr of age) is not a part of current therapy, as most CP children in Alberta receive leg therapy only ~1-2x/mo, starting around 2 yr of age. Thus, our team of researchers (U of A and U of C) and clinicians (Glenrose Hospital, Alberta Children's Hospital & Children's Hospital of Eastern Ontario) will examine if intensive leg therapy to improve walking function produces better short- and long-term effects when applied early (i.e., <2 years old) compared to usual care. We are studying children with specific forms of early brain injury to initiate movements with the impaired leg(s) for 1 hr/day, 4 day/wk for 3 mo. We randomly allocate children to either an immediate training group or a delayed training group. We will compare the change in walking and leg function over between the two groups. The delayed group will also train after the delay period for 3 mo. When the children turn 4 years old, we will compare literature information on the motor performance of similar children who have not undergone our intervention. We hope by intervening during the presumed ‘critical period’, we can improve the child's short and long-term walking and reduce future complications.
Our recent work has shown that children learn motor tasks differently than adults. Using a split-belt treadmill, which has 2 belts running at different speeds, we have shown that children take more time than adults to learn to coordinate their legs on such a treadmill. Moreover, the maturation of their learning has a surprisingly long time course that extends to puberty. The slower learning, however, may also allow children to retain the learning longer. Thus, we are studying how children, younger adults and older adults retain the learning experienced on a split-belt treadmill over 24 hours, 1 week and 2 weeks.