1. Neurological Sciences Institute, Oregon Health & Science University, Beaverton, Oregon 97006;
2. Department of Neurology, Psychiatry, and Medical Psychology, University of São Paulo, 3900 Ribeirão Preto, Brazil;
3. Department of Kinesiology, Katholiecke Universiteit Leuven, 3000 Leuven, Belgium; and
4. School of Human Kinetics, Brain Research Centre, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada