Investigators and Program Directors
Xiang Yang Chen
Research Scientist, Wadsworth Center, Nervous System Disorders
Associate Professor, School of Public Health, Biomedical Sciences
Ph.D., Neurophysiology, University of Hong Kong (1990)
Postdoctoral training, Wadsworth Center, New York State Department of Health and State University of New York at Albany
E-mail: chenx@wadsworth.org
Research Interests
Spinal cord function is normally controlled by the brain. When injury or disease removes or distorts this influence, function changes, and spasticity and other disabling problems appear. The mechanisms of supraspinal control of spinal cord function are not well understood. Better understanding how descending influence controls spinal reflexes could lead to novel methods for assessing spinal function after injury or disease, and for inducing and guiding functional recovery. Operant conditioning of the spinal stretch reflex (i.e., the tendon jerk) or of its electric analog, the H-reflex, is a new model for exploring long-term descending control over the spinal cord. It also provides a new method for assessing spinal function after injury or disease. Motivated by a paradigm in which reward depends on reflex amplitude, rats, like monkeys and humans, can gradually increase (i.e., up-conditioning) or decrease (i.e., down-conditioning) H-reflex amplitude. Currently, we are using this H-reflex conditioning model in freely moving rats to define which descending pathways from which brain areas are essential for developing and maintaining the conditioned reflex change. We are also using this rat model to investigate effects of potential therapeutic strategies in improving recovery after spinal cord injury. Because this conditioned reflex change is accompanied by long-term plasticity within the spinal cord, we have begun to investigate whether H-reflex conditioning affects function in locomotion and whether it can improve locomotor function after spinal cord injury. This work should lead to new understanding of the processes that underlie vertebrate learning. In addition, it may contribute to the development of new therapeutic techniques and new rehabilitation methods for patients with spinal cord injury and other diseases that affect the spinal cord (e.g., multiple sclerosis, amyotrophic lateral sclerosis, etc.).
Contact Information
Phone: 518-486-4916
Fax: 518-486-4910
E-mail: chenx@wadsworth.org