1. Department of Neurology; Justus Liebig University; Klinikstrasse 33 35392 Giessen Germany
2. Department of Neurology; University Medical Center; Johannes Gutenberg-University; 56101 Mainz Germany
3. Department of Nuclear Medicine; University Medical Center; Johannes Gutenberg-University; 56101 Mainz Germany
4. Department of Clinical Neurophysiology; The Sahlgrenska Academy of Gothenburg University; 41345 Gothenburg Sweden