1. School of Health Professions, University of Texas Medical Branch, Galveston and Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, TX,
2. Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, TX
3. Parkinson's Disease Research, Education and Clinical Center, Michael E. DeBakey Veterans Affairs Medical Center and Department of Neurology, Baylor College of Medicine, Houston, TX
4. School of Health Professions, University of Texas Medical Branch, Galveston, TX, USA