1. FB Horak, PT, PhD, is Research Professor of Neurology and Adjunct Professor of Physiology and Biomedical Engineering, Department of Neurology, Oregon Health and Sciences University, West Campus, Building 1, 505 NW 185th Ave, Beaverton, OR 97006-3499 (USA).
2. DM Wrisley, PT, PhD, NCS, is Assistant Professor, Department of Rehabilitation Science, University at Buffalo, Buffalo, New York.
3. J Frank, PhD, is Dean of Graduate Studies, Department of Kinesiology, University of Windsor, Windsor, Ontario, Canada.