Thorsten Fehr1, Manfred Herrmann2. 1. Center for Cognitive Sciences, Department of Neuropsychology and Behavioural Neurobiology, University of Bremen, Germany; Center for Advanced Imaging, University of Bremen, Germany. Electronic address: fehr@uni-bremen.de. 2. Center for Cognitive Sciences, Department of Neuropsychology and Behavioural Neurobiology, University of Bremen, Germany; Center for Advanced Imaging, University of Bremen, Germany.