1. Centre de Biophysique Moléculaire, UPR 4301, CNRS, Université d’Orléans, rue Charles Sadron, 45071 Orléans, Cedex 2, France
2. Department of Physiology of Cognitive Processes and MR Neuroimaging Agents, Max Planck Institute for Biological Cybernetics, Max-Planck-Ring 8, 72076 Tubingen, Germany
3. Department of Imaging Science and Biomedical Engineering, University of Manchester, Manchester, M13 9PT, U.K.