[1] Hosp Special Care, Dept Psychol, New Britain, CT USA
[2] Univ Oklahoma, Hlth Sci Ctr, Laureate Inst Brain Res, Tulsa, OK USA
[3] Temple Univ, Philadelphia, PA 19122 USA
[4] Univ Toronto, Div Geriatr Psychiat, Dept Psychiat, Toronto, ON M5S 1A1, Canada
[5] Georgetown Univ, Dept Neurosci, Washington, DC USA
[6] Univ Cambridge, Dept Psychiat, Cambridge, England
[7] Univ Cambridge, MRC, Wellcome Trust Behav & Clin Neurosci Inst, Cambridge, England
[8] American Univ, Dept Psychol, Washington, DC 20016 USA