1. Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston (M.E.G.).
2. Departments of Clinical Neurological Sciences, Anatomy and Cell Biology, and Epidemiology and Biostatistics, Schulich School of Medicine and Dentistry (L.A.S.), Western University, London, ON, Canada.
3. Heart and Brain Laboratory (L.A.S.), Western University, London, ON, Canada.
4. Robarts Research Institute (L.A.S.), Western University, London, ON, Canada.