Department of Psychiatry, University of Wisconsin Madison, WI, USA.
Front Psychol. 2013 Aug 20;4:542. doi: 10.3389/fpsyg.2013.00542. eCollection 2013.
Dreaming-a particular form of consciousness that occurs during sleep-undergoes major changes in the course of the night. We aimed to outline state-dependent features of consciousness using a paradigm with multiple serial awakenings/questionings that allowed for within as well as between subject comparisons. Seven healthy participants who spent 44 experimental study nights in the laboratory were awakened by a computerized sound at 15-30 min intervals, regardless of sleep stage, and questioned for the presence or absence of sleep consciousness. Recall without content ("I was experiencing something but do not remember what") was considered separately. Subjects had to indicate the content of the most recent conscious experience prior to the alarm sound and to estimate its duration and richness. We also assessed the degree of thinking and perceiving, self- and environment-relatedness and reflective consciousness of the experiences. Of the 778 questionings, 5% were performed during wakefulness, 2% in stage N1, 42% in N2, 33% in N3, and 17% in rapid eye movement (REM) sleep. Recall with content was reported in 34% of non-REM and in 77% of REM sleep awakenings. Sleep fragmentation inherent to the study design appeared to only minimally affect the recall of conscious experiences. Each stage displayed a unique combination of characteristic features of sleep consciousness. In conclusion, our serial awakening paradigm allowed us to collect a large and representative sample of conscious experiences across states of being. It represents a time-efficient method for the study of sleep consciousness that may prove particularly advantageous when combined with techniques such as functional MRI and high-density EEG.
做梦——睡眠期间发生的一种特殊形式的意识——在夜间会发生重大变化。我们旨在使用具有多次连续唤醒/询问的范式来概述意识的状态依赖性特征，这允许进行内部和之间的比较。七名健康参与者在实验室度过了 44 个实验研究之夜，无论睡眠阶段如何，他们都会每隔 15-30 分钟被计算机声音唤醒，并被询问是否存在睡眠意识。单独考虑没有内容的回忆（“我正在经历一些事情，但不记得是什么”）。在闹钟声响起之前，参与者必须指出最近的有意识体验的内容，并估计其持续时间和丰富度。我们还评估了体验的思维和感知程度、自我和环境相关性以及反思意识。在 778 次询问中，5%是在清醒时进行的，2%是在 N1 期进行的，42%是在 N2 期进行的，33%是在 N3 期进行的，17%是在快速眼动（REM）睡眠期进行的。非快速眼动睡眠中的 34%和 REM 睡眠中的 77%觉醒时报告有内容的回忆。研究设计中固有的睡眠碎片化似乎仅对有意识体验的回忆产生最小的影响。每个阶段都显示出睡眠意识的独特组合特征。总之，我们的连续唤醒范式使我们能够在不同的状态下收集大量有代表性的有意识体验样本。它代表了一种研究睡眠意识的高效方法，当与功能磁共振成像和高密度脑电图等技术结合使用时，可能特别有利。
