Prof. Jonathan R. Wolpaw
Director, National Center for Adaptive Neurotechnologies
Wadsworth Center. New York State Deparment of Health
Department of Neurology, Albany Stratton VA Medical Center
Department of Neurology, Neurological Institute, Columbia University

Title:  The Spinal Cord Functions as a Negotiated Equilibrium: Scientific and Clinical Implications

Abstract: Like the rest of the CNS, the spinal cord undergoes activity-dependent plasticity during development, as behaviors are acquired and maintained throughout life, and in response to trauma and disease. Nevertheless, it continues to serve all the behaviors in an individual’s repertoire. How does this reliability come about? How does the spinal cord remain a reliable final common pathway throughout life? Recent studies suggest the following hypothesis. The substrate of each behavior is a network of plasticity that operates as a hierarchy in which plasticity in the brain induces and maintains plasticity in the spinal cord. Each time the behavior occurs, deviations from its key features (i.e., deviations from optimal performance) guide changes in its substrate that reduce the deviations: the spinal cord provides the brain with performance information that guides appropriate changes in the hierarchy of plasticity that produces the behavior. All the behaviors in the repertoire undergo this process concurrently; each is an independent agent that repeatedly induces plasticity to preserve its key features despite the plasticity induced by other behaviors. The aggregate process is a negotiation among the behaviors; they negotiate the properties of the spinal neurons and synapses that they all use. The ongoing negotiation maintains the spinal cord in an equilibrium – a negotiated equilibrium – that serves all the behaviors. This hypothesis makes major predictions that are borne out by experiment. Furthermore, it underlies a promising new approach to restoring useful function to people with spinal cord injuries or other disorders.

Short CV:

Over the past 30 years, Dr. Wolpaw’s laboratory has developed and used operant conditioning of spinal reflexes as a model for defining the plasticity underlying learning. His group’s recent work shows that reflex conditioning can guide spinal cord plasticity in spinal cord-injured rats and can thereby improve locomotion. Clinical researchers are now finding evidence that such conditioning can improve locomotion in people with partial spinal cord injuries. For the past 20 years, Dr. Wolpaw has also led development of EEG-based brain-computer interface (BCI) technology to provide non-muscular communication and control to people who are paralyzed. Most recently, his group has begun to provide BCI systems to severely disabled people for daily use in their homes.