Budget Amount *help |
¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1987: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1986: ¥1,000,000 (Direct Cost: ¥1,000,000)
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Research Abstract |
The REM-nonREM(NREM) cycle during sleep has been investigated from many perspectives and some hypotheses has been postulated. They are a sleep-independent, a sleep-dependent,and a reset hypotheses). In the present study. we investigated how the REM-NREM cycle was modified by a sleep-wake transition, using the method of sleep interruption during nocturnal sleep. The subjects were forty four male students, aged 18-23 years. After the adaptation and the baseline nights(BNs),three or four consecutive nights were interrupted by a forced awakening once a night(EN). A total of 129 ENs were analyzed. Ss were awakened after they had slept the first sleep cycle plus 20 minutes of NREM sleep in the following 2nd cycle. Durations of the awake period were between 10 and 90 minutes. After the awake period, Ss were permitted to sleep again. Each night including the awake period was monitored by poly-somnography. When Ss fell back to sleep after interruption, the REM latencies showed a bi-modal distribution; SOREMP(sleep onset REM period) or NonSOREMP. We suggest that the appearance rate of SOREMP(SORMP%)is influenced by the circadian REM rhythm, the amouht of NREM sleep before interruption,and might be influenced by the length of interruption,and by individual difference. The ENs was divided into two groups;SOREMP and NonSOREMP nights. The fluctuations of REM episode probagility (FRPs) were drawn by adding up each REM sequence separately for the two groups. According to the hypothetical models,FRPs were compared with the FRP of BN. In SOREM nights, none of the three models corresponded with BNs. In NonSOREMP nights,the sleep-dependent model can correspons to BN. Nevertheless, an alternative interpretation of the modified reset model is possible. In this model,the re-setting of REM-NREM cycle may not occur at the onset of sleep but in the period of falling asleep.
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