About the Japanese Society of Sleep Research

Introduction

　Sleep is a time of rest and relaxation that accounts for approximately one-third of our lives; however, its role and importance have been scientifically clarified only relatively recently.

　In recent years, the amount of time spent sleeping has shortened owing to the diversification of lifestyles and the shift to nighttime activities, which has resulted in various adverse effects. For example, traffic accidents caused by daytime sleepiness due to lack of sleep have been on the rise, and bullet train (Shinkansen) drivers falling asleep are probably fresh in your minds. Daytime sleepiness not only causes accidents but also lowers productivity in daily work and study. If this condition is prolonged, it can affect the mind and body, causing anxiety and depression. Sleep disorders can also lead to socioeconomic problems. In addition to sleep deprivation, one in every four or five people in Japan now has sleep-related problems. There is a growing trend to treat sleep not only from the perspective of “sleep medicine,” but also from the three perspectives of “sleep sociology,” which looks at socioeconomic issues, and “sleep science,” which studies the roles and mechanisms of sleep. Putting these three areas together, a new academic system called “somnology” has been established.

History of Sleep Research

　Modern scientific sleep research can be traced back to Economo's study (1926), which examined the brain damage caused by encephalitis lethargica. This research was supported by the work of Hess et al. (1954), who succeeded in inducing sleep by electrical stimulation of the brain, and by Moruzzi and Magoun's (1949) discovery of the ascending brainstem reticular activating system, a neural mechanism of arousal, which finally brought the mechanisms of sleep and arousal under scrutiny and ushered in full-scale sleep research. A major contribution to these studies was Berger's (1929) discovery of the electroencephalogram that successfully recorded electrical activity from the human scalp. The discovery of rapid eye movement (REM) sleep in humans by Aserinsky and Kleitman (1953) at the University of Chicago, United States, led to dramatic developments in sleep research, followed by the discovery of REM sleep in dogs and cats by Dement (1958) at the University of Chicago, Jouvet (1959) in France, and Shimazono (1960) in Japan.

　In the late 1990s, imaging studies of cerebral blood flow during sleep began to reveal which parts of the brain were active during each stage of sleep and which parts of the brain were affected by sleeping pills. Narcolepsy, a classic disease characterized by hypersomnia (sleep attack) and cataplexy, has long been known to exist; however, in 1999, the development of rapidly advancing research techniques led to the discovery that the level of orexin, a neuropeptide, is reduced in the spinal fluid of narcoleptic dogs. Thus, the development of information technology and electronics, as well as analyses at the molecular level accompanying advances in molecular biology, are bringing about new discoveries one after another, and the development of sleep science is expected to bring about major advances in the diagnosis and treatment of sleep disorders.

Future Roles of the Japanese Society of Sleep Research

　The first is to develop Sleep and Biological Rhythms (SBR), an international journal of the Japanese Sleep Society, into a first-class journal. Sleep research in Japan has been actively conducted not only by Japanese researchers working abroad, but also by leading international researchers in Japan. At the beginning of the 20th century, Kuniomi Ishimori in Japan (1909) and Henri Piéron in France (1913) proposed at almost the same timing, the existence of “sleep substances” involved in inducing and maintaining sleep. They independently injected cerebrospinal fluid from a dog that had been deprived of sleep and was very drowsy into the brain of another dog and observed that the dog, which was injected with fluid, was asleep; however, it was only recently that the actual nature of the sleep substance became clear. Currently, approximately 30 sleep-related substances have been identified in animal brain, blood, and urine samples. In Japan, Shojiro Inoue et al. identified uridine and oxidized glutathione as sleep substances. More recently, Hayaishi et al. discovered prostaglandin D2, other cytokines, and adenosine, making Japan a world leader in basic research on sleep substances. We hope to disseminate the results of international research in Japan through the SBR. In addition, the detailed observation and accumulation of cases in clinical and basic research are unparalleled worldwide, and our originality in the field of human chronobiology should be highly evaluated. We should be prouder of these achievements, and I think it is important to make SBR an international journal and further develop it into world-leading journal.

　The second goal is to further promote the creation of centers for sleep research and medicine. In Japan, departments of sleep science are being established in various parts of the country, starting with the Shiga University of Medical Science. The purpose of establishing these institutes was to conduct sleep research focusing on sleep science and sleep disorders, to develop sleep medicine for citizens, and to train doctors and paramedical staff. Such a comprehensive concept is unique, even from an international perspective. A system that has never existed in Europe or the United States of America is being established and is about to spread in Japan. We would like to support the spread of these centers, as well as other courses, to other universities throughout Japan and further expand their base beyond the university itself.

　The third is collaboration with other countries worldwide. The Society has held and participated in several international symposia and conferences in cooperation with the World Federation of Sleep Research Societies and the American Academy of Sleep Medicine. The Asian Sleep Research Society, in which the Japanese Society of Sleep Research participated, was chaired by Teruo Okuma (1994-1997), Shojiro Inoue (1997-2000), and Tatsuro Ota (2000-2004), and is currently chaired by Professor Kumar of India. International exchange will continue to be active in Europe, the United States, and Asia.

　Fourth, sleep sociology should be promoted as a comprehensive science for maintaining a healthy society. In recent years, the shift to a 24-hour-a-day society has resulted in various problems and adverse effects on social life. Stress, overwork, and sleep deprivation seem to cause an increase in lifestyle-related diseases, depression, and the breakdown of people's healthy lives, as well as trigger industrial accidents and make work and school life more difficult. Notably, it is gradually becoming recognized that the socioeconomic losses due to such diseases and inadequate work and schooling are enormous. Remembering that sleep and rest, along with eating behavior, are fundamental to a healthy human life, we believe that the challenge of the 21st century is to promote a social lifestyle that places an even greater emphasis on sleep. At this juncture, a landmark event occurred in 2004 when “sleep studies” were approved as a subdivision of the Science Research Fund. It can be said that the entire country has become more committed to sleep research and health promotion. From this perspective, I believe that every one of us as members of the society must take our responsibilities seriously.

　As mentioned above, the Japanese Society of Sleep Research was established to promote scientific sleep research, enhance sleep-related medicine and medical care, and promote national health. The purpose of this website is to provide scientific knowledge on sleep science and clinical sleep to the public and medical institutions. We, the members of the society, would like to make every effort to make this website useful for the promotion of sleep health, and we would appreciate your strong support and cooperation.