1. Max Planck Institute of Psychiatry (U.P., E.C., F.L., D.S., G.K.S.), 80804 Munich
2. the Departments of Neurology, Technical University of Munich (T.A.), 81675 Munich, Germany
3. the Institute of Semeiotica Medica, University of Padua (C.P.), Padua, Italy
4. Centre National de la Recherche Scientifique (L.J., D.S.), 34094 Montpellier Cedex 05, France