1. Behavioral Pharmacology Research Unit, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr, Baltimore, MD, USA
2. Neuropsychopharmacology and Brain Imaging, Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich, Lenggstr. 31, Zurich, Switzerland
3. Department of Psychiatry, Psychotherapy and Psychosomatics, Center for Addictive Disorders,University Hospital for Psychiatry Zurich, Lenggstr. 31, Zurich, Switzerland
4. Department of Psychology, University of California, Davis, 1 Shields Dr, Davis, CA, USA
5. Center for Mind and Brain, University of California, Davis, 267 Cousteau Pl, Davis, CA, USA