1. Institute of Vegetative Physiology The University of Köln Robert-Koch-Str. 39 50931 Köln
2. Institute of Neurophysiology, Center of Physiology and Pathophysiology The University of Köln Robert-Koch-Str. 39 50931 Köln
3. Axiogenesis AG Joseph-Stelzmann-Str. 50 50931 Köln Germany
4. Institute of Physiology I University of Bonn Argelanderstrasse 2a 53115 Bonn