1. P Silsupadol, PT, BS(Hons), and KC Siu, PT, BS, are doctoral students, Department of Human Physiology, University of Oregon, Eugene, Ore
2. A Shumway-Cook, PT, PhD, is Associate Professor, Division of Physical Therapy, University of Washington, Seattle, Wash
3. MH Woollacott, PhD, is Professor, Department of Human Physiology, and Member, Institute of Neuroscience, University of Oregon