1. Department of Psychiatry Shizuoka Saiseikai General Hospital 1‐1‐1, Oshika, Suruga‐ku, Shizuoka 422‐8527 Japan
2. Autonomic Nervous System Consulting 1‐1‐1, Oshika, Suruga‐ku, Shizuoka 422‐8527 Japan
3. Department of Stress Disorders Research, Tokyo Institute of Psychiatry 2‐1‐6, Kamikitazawa, Setagaya‐ku, Tokyo 156‐8506 Japan
4. Research and Development Department, Hakuju Institute for Health Science Co., Ltd. 1‐37‐5, Tomigaya, Shibuya‐ku, Tokyo 151‐0063 Japan
5. Bio‐Self‐Regulating Science Laboratory Obihiro University of Agricultural and Veterinary Medicine Inada‐Cho, Obihiro Hokkaido 080‐8555 Japan