1. Neurology Department, University of Michigan, Ann Arbor (L.E.S., D.L.B., E.R.).
2. Division of Geriatrics, University of California, San Francisco (Y.S., A.M.V., R.L.S.).
3. Neurology Department, Ohio State University, Columbus (J.F.B.).
4. San Francisco Veterans Affairs, California (R.L.S.).