1. From the Stroke and Dementia Research Centre, St George’s, University of London, London, United Kingdom (B.P., A.J.L., A.W.C., T.R.B., H.S.M.); Department of Neuroradiology, Atkinson Morley Neuroscience Centre, St George’s Hospital, London, United Kingdom (P.R., A.D.M.); and Department of Psychology, Institute of Psychiatry, London, United Kingdom (R.G.M.).