WS7 – Operant Conditioning of Spinal Reflexes in Human Subjects

Operant conditioning is a powerful method to induce behavioral learning. Through operant conditioning, modification of a behavior is brought about by the consequence of that behavior. In 1983, Wolpaw and his colleagues showed for the first time that a properly designed operant conditioning protocol could change the spinal stretch reflex (SSR), a largely monosynaptic behavior arising from the excitation of muscle spindle afferents. Variations of this protocol have been applied to condition the SSR or its electrical analog, the H-reflex, in monkeys, rats, mice, and humans. All of these have confirmed that a specific change (i.e., up- or down-regulation) can be induced in the activity of a targeted reflex pathway through operant conditioning. Reflex conditioning protocols are designed to induce and maintain a long-term change in descending influence over the spinal reflex pathway, and to thereby produce targeted neuroplasticity in that pathway. Because a spinal reflex pathway serves many different behaviors, the plasticity produced by this conditioning can change those other behaviors in which the conditioned reflex pathway participates. In animals or people with partial spinal cord injuries, appropriate reflex conditioning can improve locomotion. Furthermore, in people with spinal cord injuries, appropriate reflex conditioning can trigger widespread beneficial plasticity. Operant conditioning protocols are a promising new therapeutic method that could complement other rehabilitation methods and enhance functional recovery. Their successful use requires close adherence to appropriately designed procedures, as well as close attention to accommodating and engaging the individual subject in the conditioning process.


Aiko K. Thompson, Ph.D.: Associate Professor, Department of Health Sciences and Research, College of Health Professions at the Medical University of South Carolina

Jonathan R. Wolpaw, MD: Director, National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Dept of Health; Research Physician, Department of Neurology, Stratton VA Medical Center


First, This workshop will introduce the participants to the theory and history behind operant conditioning of spinal reflexes. Second, the participants will learn the basics of spinal reflex testing in humans, experience dynamic H-reflex modulation testing, and, in addition, learn other methods for assessing spinal inhibition and excitation. Third, the participants will learn the soleus H-reflex operant conditioning protocol through demonstration and hands-on experience.



Expected audience

Students, postdoctoral fellows, clinicians, and investigators who are interested in spinal reflex testing and/or in operant conditioning of spinal reflexes.

Previous knowledge and experience

Basic knowledge of surface EMG recording, human motor control, and/or movement disorders after CNS damage will be helpful, but is not absolutely necessary. Before or during the workshop, brief reading materials will be provided to the participants to provide basic background in human spinal reflex testing.