自己覚醒法を利用した短時間仮眠の睡眠構造と睡眠慣性におよぼす効果

Effects of self-awakening on sleep structure and sleep inertia during or after the short nap

Kaida Kousuke

Nittono Hiroshi

Hayashi Mitsuo

Hori Tadao

広島大学総合科学部紀要. IV, 理系編

Memoirs of the Faculty of Integrated Arts and Sciences, Hiroshima University. IV, Science reports

本研究の目的は, 短時期仮眠における自己覚醒の企図が, 睡眠構造および睡眠慣性に及ぼす影響を検討することである。実験は, 自分で目覚める自己覚醒条件と,実験者が強制的に覚醒させる強制覚醒条件の参加者内比較計画で行った。覚醒水準の評価には, 聴覚オドボール課題により算出された事象関連電位のP300と課題正反応時間,Visual Analog Scale (Vas)による主観的覚醒水準評定値を用いた。睡民構造の詳細な検討のために,Hori et al. (1994)の脳波段階判定(9段階)を用いた。実験参加者は,大学生・大学院生14名であった。実験参加者は,4minの聴覚オドボール課題と1minのVAS評定からなる計5分間の課題を2セッション(計10分間)行った。その後,約20分間の仮眠をとり,覚醒後に同様の課題を6セッション(計30分間)行った。本研究の結果,自己覚醒を用いて出眠した場合には,強制覚醒の場合と比べて,P300振幅は大きくなり,主観的眠気は低減していた。また,自己覚醒を意図した場合には,睡眠構造が浅くなる傾向があった。これらの結果から,強制覚醒よりも自己覚醒をもちいた仮眠が,午後の眠気を抑える方法として有効であることが示された。(518語)

The aim of this study was the investigation of the effects of self-awakening on sleep inertia and sleep structure at the short nap. The participants were take part in the self-awakening and forced-awakening condition. In the self-awakening condition, participant woke up by themselves. However, experimenter in the forced-awakening condition waked participants up. The physiological arousal level and subjective sleepiness were evaluated by P300 of the event related potential (ERP) and visual analog scale (VAS). For evaluating the sleep structure elaborately, we used the Hori's EEG stages. Participants were 14 healthy college students. They participated the task consist of auditory oddball task (4 min) and VAS rating (1 min). Participant carried out two sessions (10 min) before the nap. Thereafter, they took a short nap around 20 min. After the nap, they carried out six sessions (30 min) again. P300 amplitude was lower after forced -awakening than self-awakening. On the other hand, subjective sleepiness was greater after the forced-awakening than self-awakening. And sleep structure was deeper during the forced-awakening than self-awakening. Those results suggest that a short nap with self-awakening was more useful than with forced-awakening.

午後の眠気

短時間仮眠

自己覚醒

睡眠慣性

脳波段階

post lunch dip

a short nap

self-awakening

sleep inertia

Hori's EEG stage

Medical sciences [ 490 ]

jpn

広島大学総合科学部

[Created] 2006-03-21

[ISSN] 1340-8364

[NCID] AN10435936