Evidence for a spinal stepping generator in man. Electrophysiological study

We present some evidence favouring the presence of a spinal stepping generator in humans. Electrophysiological studies have shown that the spinal cord even deprived of supraspinal influence can generate rhythmic activity, and that some elements of the spinal circuitry on which the generation of stepping rhythmic relies in lower vertebrates exist in man. Moreover, comparison of the variations of the polysynaptic spinal flexor reflex in normal subjects and paraplegic patients brought about some evidence that normal subjects use a spinal locomotor center. Nevertheless, these studies do not absolutely prove the existence of a central pattern generator in man.