Effects of H-reflex operant conditioning in humans

Abstract

Operant conditioning of a spinal reflex can modify specific spinal cord pathways and can thereby affect behaviors that use these pathways. We have shown that down-conditioning the soleus H-reflex during standing can improve walking in people with chronic incomplete spinal cord injury (SCI); after successful conditioning people walked faster and more symmetrically with better locomotor EMG activity [1]. Based on this success, we are currently testing the hypothesis that locomotor reflex activity can be further improved toward a more normal pattern by reducing the soleus H-reflex size during the swing phase of the gait cycle, where the H-reflex is very small or absent in normal subjects but abnormally large in people with spasticity due to chronic SCI.