1 Department of Clinical Neuropsychology, VU-University, van der Boechorststraat 1, 1081 BT Amsterdam, The Netherlands College of Nursing, The University of Iowa, Iowa City, IA 52242, USA CHU Clermont-Ferrand, Clinical Pharmacology Centre, University Hospital, Clermont-Ferrand, France National Ageing Research Institute, P.O. Box 31, Parkville, Vic. 3052, Australia Department of Neuroscience, University of Turin Medical School and National Institute of Neuroscience, Turin, Italy Physiological Psychology, University of Bamberg, Markusplatz 3, Bamberg 96045, Germany.