1. Institute of PhysiologyUniversity Medical Center of the Johannes Gutenberg University MainzDuesbergweg 6 D‐55120 Mainz Germany
2. Department of Molecular AnatomySchool of MedicineUniversity of the Ryukyus 207 Uehara Nishihara Okinawa 903‐0215 Japan
3. University Medical Center Hamburg EppendorfDevelopmental Neurophysiology Falkenried 94 D‐20251 Hamburg Germany
4. Department of NeurophysiologyHamamatsu University School of Medicine Hamamatsu Shizuoka 431‐3192 Japan