Research Calendar

Dr V Reggie Edgerton

  • Dr. V. Reggie Edgerton received his Ph.D. in Exercise Physiology from Michigan State University and has been a Professor at the University of California, Los Angeles, since 1968. Dr. Edgerton’s laboratory focuses on two main research questions: How do neural networks in the lumbar spinal cord of mammals, including humans, regain control of standing, stepping and voluntary control of fine movements after paralysis, and how can these motor functions be modified by chronically imposing activity-dependent interventions after spinal cord injury? Previous work has shown that the mammalian spinal cord, without input from the brain, can learn specific complex tasks such as standing and stepping. Dr. Edgerton and colleagues have recently observed that electrodes placed epidurally over the lumbosacral cord in the rat can be used to neuromodulate spinal circuitry so that after complete cord transection, when used in combination with select pharmacological compounds, the rat is capable of performing full weight bearing stepping at different speeds and load. His lab has identified three effective ways to neuromodulate the spinal cord to improve and regain function: tonic stimulation of spinal circuitry, use of pharmacological compounds and repetitive training of motor tasks. Application of these interventions has made it possible to recover full weight bearing standing and stepping after complete paralysis in the rat. More recent experimental data have shown that epidural stimulation alone can enable individuals with complete paralysis (> 2 years) can regain the ability to stand independently and significant levels of voluntary control of movement of the legs. Largely using animal models of complete paralysis Edgerton and colleagues are aggressively developing and testing these interventions in humans, in an attempt to determine the mechanisms of recovery potential formulated from the perspective of how spinal networks can be “fine-tuned” to facilitate the performance of a wide range of complex motor tasks. Each of these interventions is used to modulate the excitability of spinal networks associated with posture and locomotion to a physiological state that approaches a motor threshold. This is a physiological state that enables motor control by engaging task specific proprioception as well as newly acquired voluntary input to the spinal circuitry. Dr. Edgerton will discuss the impact this work may have in the treatment of SCI.

    As part of these efforts Edgerton and colleagues have focused on technological advances to facilitate the application of the different methods of neuromodulation of spinal circuitry. These include the use of robotic devices, complex electrode arrays and more sophisticated stimulation devices for use in real-time. In concert with these efforts, considerable focus is directed toward integrating neural models of locomotion with actual musculoskeletal properties that are subject-specific.

    All of these projects are being performed with national and international collaborators. Some of the principal universities and institutions are Caltech, University of Louisville, University of California at San Diego, Irvine, Davis and San Francisco, and the University of Puerto Rico.