Rosenblum Yevgenia, Weber Frederik D, Rak Michael, Zavecz Zsófia, Kunath Nicolas, Breitenstein Barbara, Rasch Björn, Zeising Marcel, Uhr Manfred, Steiger Axel, Dresler Martin
Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Nijmegen, Netherlands.
Department of Sleep and Cognition, Netherlands Institute for Neuroscience, Amsterdam, Netherlands.
Sleep. 2024 Feb 8;47(2). doi: 10.1093/sleep/zsad321.
Voluntary sleep restriction is a common phenomenon in industrialized societies aiming to increase time spent awake and thus productivity. We explored how restricting sleep to a radically polyphasic schedule affects neural, cognitive, and endocrine characteristics.
Ten young healthy participants were restricted to one 20-minute nap opportunity at the end of every 4 hours (i.e. six sleep episodes per 24 hours) without any extended core sleep window, which resulted in a cumulative sleep amount of just 2 hours per day (i.e. ~20 minutes per bout).
All but one participant terminated this schedule during the first month. The remaining participant (a 25-year-old male) succeeded in adhering to a polyphasic schedule for five out of the eight planned weeks. Cognitive and psychiatric measures showed modest changes during polyphasic as compared to monophasic sleep, while in-blood cortisol or melatonin release patterns and amounts were apparently unaltered. In contrast, growth hormone release was almost entirely abolished (>95% decrease), with the residual release showing a considerably changed polyphasic secretional pattern.
Even though the study was initiated by volunteers with exceptional intrinsic motivation and commitment, none of them could tolerate the intended 8 weeks of the polyphasic schedule. Considering the decreased vigilance, abolished growth hormone release, and neurophysiological sleep changes observed, it is doubtful that radically polyphasic sleep schedules can subserve the different functions of sleep to a sufficient degree.
在工业化社会中，自愿限制睡眠是一种常见现象，目的是增加清醒时间从而提高生产力。我们探究了将睡眠限制在一种极端多相睡眠模式下如何影响神经、认知和内分泌特征。
10名年轻健康参与者被限制在每4小时结束时仅有一次20分钟的小睡机会（即每24小时有6次睡眠时段），没有任何延长的核心睡眠时间，这导致每天的累计睡眠时间仅为2小时（即每次约20分钟）。
除一名参与者外，所有参与者在第一个月内就终止了这种睡眠模式。剩下的参与者（一名25岁男性）在计划的8周中有5周成功坚持了多相睡眠模式。与单相睡眠相比，多相睡眠期间认知和精神方面的指标有适度变化，而血液中皮质醇或褪黑素的释放模式和量明显未改变。相比之下，生长激素释放几乎完全被抑制（减少超过95%），残余释放呈现出明显改变的多相分泌模式。
尽管该研究由具有非凡内在动力和决心的志愿者发起，但他们中没有一人能够耐受预定的8周多相睡眠模式。考虑到观察到的警觉性下降、生长激素释放被抑制以及神经生理睡眠变化，极端多相睡眠模式能否充分满足睡眠的不同功能令人怀疑。
