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Updated: Aug 7, 2026

Multi-Modal Home Sleep Monitoring in Older Adults
Published on: January 26, 2019
Self-awakening, sleep inertia, and P3 amplitude in elderly people
Kosuke Kaida1, Keiko Ogawa, Hiroshi Nittono
1The Japan Society for Promotion of Science. kaidak@niih.go.jp
Abstract:
It is well known that sleepiness is sometimes experienced in the afternoon. A short afternoon nap is thought to be effective in reducing sleepiness. However, sleep inertia occurs even after a short nap, and this could be a major risk factor for injuries from falling by the elderly. In the present study, the effect of self-awakening on sleep inertia after a 20-min. nap was examined. Nine participants (M=74.1 yr., SD=5.0 yr.) took part in the three experimental conditions: the self-awakened nap, the forced-awakened nap, and the control (no-nap) conditon. Analysis showed sleepiness and performance after the nap significantly improved compared with the control condition. P3 amplitude tended to be larger after self-awakening than after forced-awakening. The present study indicates a 20-min. nap reduces afternoon sleepiness, and the application of self-awakening may contribute to higher arousal after a nap taken by this elderly group.
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