De Valck Elke, Cluydts Raymond, Pirrera Sandra
Department of Cognitive and Physiological Psychology, Vrije Universiteit Brussel, Brussels, Belgium.
J Sleep Res. 2004 Dec;13(4):295-304. doi: 10.1111/j.1365-2869.2004.00424.x.
Emerging research has shown that sleepiness, defined as the tendency to fall asleep, is not only determined by sleep pressure and time of day, but also by physiological and cognitive arousal. In this study we evaluated (i) the impact of experimentally induced cognitive arousal on electroencephalogram (EEG) defined sleep latency, and subjective, somatic and cortical arousal, and (ii) whether experimentally induced cognitive arousal enhances performance on a driving simulator test. Twelve healthy sleepers each spent three nights and the following day in the sleep laboratory: an adaptation, a cognitive arousal and a neutral testing day. In the cognitive arousal condition, a visit of a television camera crew took place and subjects were asked to be interviewed. On each testing day, a 5-min heart rate recording, subjective sleepiness and arousal scales, Multiple Sleep Latency Test and a 25-min driving simulator task were scheduled three times at 2-h intervals. Experimentally induced cognitive arousal resulted in significant increases in objective sleep latency. Significantly elevated levels of subjective and somatic arousal--as indexed by a subjective arousal scale and heart rate--were also evidenced following cognitive arousal induction. A marginally significant trend for increased cortical arousal, measured by EEG beta activity, was also found. No effects were found on driving simulator performance. These findings support the concept of cognitive arousal as a significant component in determining sleep latency. In addition, it was illustrated that cognitively induced arousal can provoke increases in somatic and possibly even cortical arousal in normal sleepers. However, this was not accompanied by an enhanced ability to perform adequately on a driving simulator test.
新兴研究表明，困倦（定义为入睡倾向）不仅由睡眠压力和一天中的时间决定，还受生理和认知唤醒的影响。在本研究中，我们评估了：（i）实验诱导的认知唤醒对脑电图（EEG）定义的睡眠潜伏期、主观、躯体和皮层唤醒的影响；（ii）实验诱导的认知唤醒是否能提高驾驶模拟器测试的表现。12名健康睡眠者每人在睡眠实验室度过三个晚上及随后的一天：一个适应日、一个认知唤醒日和一个中性测试日。在认知唤醒条件下，一个电视摄像机组前来探访，受试者被要求接受采访。在每个测试日，每隔2小时安排三次5分钟的心率记录、主观困倦和唤醒量表、多次睡眠潜伏期测试以及25分钟的驾驶模拟器任务。实验诱导的认知唤醒导致客观睡眠潜伏期显著增加。认知唤醒诱导后，主观和躯体唤醒水平也显著升高——以主观唤醒量表和心率为指标。通过脑电图β活动测量，还发现皮层唤醒有轻微的显著增加趋势。在驾驶模拟器表现方面未发现影响。这些发现支持了认知唤醒是决定睡眠潜伏期的一个重要组成部分的概念。此外，研究表明，认知诱导的唤醒可在正常睡眠者中引发躯体甚至可能是皮层唤醒的增加。然而，这并未伴随着在驾驶模拟器测试中表现能力的增强。
