1 Division of General Neurology and Ataxia Unit, Department of Neurology Federal University of São Paulo São Paulo Brazil.
2 Tecnologico de Monterrey, Escuela de Medicina y Ciencias da la Salud Monterrey Mexico.
3 Centro de Rehabilitacion e Inclusión Infantil Teleton Chihuahua Mexico.
4 Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital Toronto Ontario Canada.
5 Division of Neurology UHN Toronto Ontario Canada.
6 Division of Neurology University of Toronto Toronto Ontario Canada.