Neural Plasticity of Spinal Reflexes

Abstract

Spinal reflexes traditionally have been viewed as hard-wired, unchanging neural circuits. Studies of learning-like changes in spinal reflex excitability have shown that spinal reflex circuits are capable of long-lasting alterations under varying stimulus conditions. Simple repetitive stimuli, classical conditioning procedures, and certain instrumental learning paradigms are being used to determine the ability of spinal reflex circuits to sustain response changes. These behavioral investigations and studies of the effects of nociceptive inputs to the spinal cord are beginning to produce a greater understanding of the neural mechanisms underlying spinal reflex plasticity. These insights into the mechanisms of spinal neural process alterations are leading to a greater understanding of certain types of chronic pain. Utilizing many of the behavioral techniques shown to have effects on spinal reflex function is producing better rehabilitation of spinally injured patients, and will eventually lead to the ability to reverse the effects of many types of spinal cord injuries.