1. Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky.
2. Department of Physiology and Biophysics, University of Louisville, Louisville, Kentucky.
3. Department of J.B. Speed School of Engineering, University of Louisville, Louisville, Kentucky.
4. Department of Neurological Surgery, University of Louisville, Louisville, Kentucky.
5. Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky.