1. Department of Neurobiology, Keck School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
2. Rancho Research Institute, Rancho Los Amigos National Rehabilitation Center, Downey, California, USA.
3. SpineX, Inc., Los Angeles, California, USA.
4. Department of Neurosurgery, Keck School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
5. Brain Research Institute, Keck School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
6. Institut Guttmann, Hospital de Neurorehabilitació, Institut Universitari adscrit a la Universitat Autònoma de Barcelona, Barcelona, Badalona, Spain.
7. Department of Urology, University of Southern California, Los Angeles, California, USA.