1. Department of Physiology, University of Mainz, D-6500 Mainz, Federal Republic of Germany
2. RAF Institute of Aviation Medicine, Farnborough GU 146 TD, England
3. CNRS Laboratoire de Physiologie Neurosensorielle, F-75006 Paris, France
4. Department of Neurology, Alfried Krupp Krankenhaus, D4300 Essen, Federal Republic of Germany
5. Department of Neurology, University of Tuebingen, D-7400 Tuebingen, Federal Republic of Germany
6. Department of Otolaryngology, Klinikum Grosshadern, D-8000 Munich, Federal Republic of Germany