1 From the Departments of Epidemiology and Population Health and Neurology and Neurological Sciences (V.W.H.), Stanford University, CA; and Department of Psychology and Graduate School of Biomedical Science and Engineering (M.F.E.), University of Maine, Orono. vhenderson@stanford.edu.
2 From the Departments of Epidemiology and Population Health and Neurology and Neurological Sciences (V.W.H.), Stanford University, CA; and Department of Psychology and Graduate School of Biomedical Science and Engineering (M.F.E.), University of Maine, Orono.