自己覚醒の習慣が睡眠と日中覚醒に及ぼす影響に関する研究 <学位論文要旨>

Graduate School of Integrated Arts and Sciences, Hiroshima University Insuffi cient and restless sleep makes it diffi cult to recover from fatigue, and can prevent people from having a productive day. Most people have to terminate sleep to go to work or school, usually relying on external means (such as an alarm clock) to awaken at a certain time and feel strong sleepiness after awakening. Some people habitually wake up at a certain time every morning, in the absence of an external signal. The present study focused on this "habitual selfawakening". Questionnaire research showed that people who engaged in habitual self-awakening reportedly feel better upon awakening and are subsequently less sleepy during the daytime. In the present study, it was also examined the effects of habitual self-awakening on sleep structure and autonomic nervous system activity before awakening, and on mood after awakening. From the results, it is suggested that habitual self-awakening prepares individuals for awakening during the last hour of nocturnal sleep, without signifi cantly disturbing the sleep structure of the entire night. This process facilitates a smooth transition from sleep to wakefulness and produces positive benefits after awakening, including as waking up relatively easily and feeling less sleepy subsequent to waking up. In this way the habit of self-awakening would enhance daytime function and contribute toward improvement of sleep problems in present day.