1. From the Departments of Neurosciences (P.L., R.R.) and Family and Preventive Medicine (R.R., L.L.), University of California–San Diego School of Medicine, San Diego, Calif; the Department Neurology (P.L.), Veterans Administration Medical Center, San Diego, Calif; and the National Institute of Neurological Disorders and Stroke (M.E., M.W., J.M.), Bethesda, Md.