1 Department of Psychiatry and Behavioral Sciences, Stanford University, 401 Quarry Road, Stanford, California 94304, USA; and at the Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), 3801 Miranda Avenue, Palo Alto, California 94304, USA.
2 Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany. Martinistr 52, 20246 Hamburg, Germany.
3 Department of Psychology, Stanford University, 450 Serra Mall, Stanford, California 94305, USA.