Boivin D B, Czeisler C A, Dijk D J, Duffy J F, Folkard S, Minors D S, Totterdell P, Waterhouse J M
Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass, USA.
Arch Gen Psychiatry. 1997 Feb;54(2):145-52. doi: 10.1001/archpsyc.1997.01830140055010.
Several studies of healthy volunteers have revealed that subjective mood may vary with the duration of prior wakefulness and with the time of day. However, in these studies, the effects of extended wakefulness and circadian phase remained confounded, and the interaction of these 2 processes could not be assessed quantitatively.
In the present study, a total of 24 healthy young subjects (16 men, 8 women) lived on a 30-hour sleep-wake schedule for 19 to 23 days or on a 28-hour sleep-wake schedule for 33 to 36 days; both schedules induced desynchrony between the subjects' sleep-wake cycle and their endogenous circadian pacemaker. Subjective mood was assessed by 2 types of visual analog scales, which were administered twice every 2 hours and every 20 minutes, respectively, during all scheduled wakefulness episodes. A circadian phase and an interval elapsed since awakening were attributed to each data point, and circadian and wake-dependent fluctuations of mood were assessed.
A significant variation of mood with circadian phase was observed, but no reliable main effect of the duration of prior wakefulness was found. A statistically significant interaction of circadian and wake-dependent fluctuations was evident; when the analysis was restricted to specific circadian phases, mood improved, deteriorated, or remained stable with the duration of prior wakefulness.
These results indicate that, in healthy young subjects, subjective mood is influenced by a complex and nonadditive interaction of circadian phase and duration of prior wakefulness. The nature of this interaction is such that moderate changes in the timing of the sleep-wake cycle may have profound effects on subsequent mood.
多项针对健康志愿者的研究表明，主观情绪可能会随着先前觉醒时长以及一天中的时间而变化。然而，在这些研究中，长时间觉醒和昼夜节律相位的影响仍然相互混淆，无法对这两个过程的相互作用进行定量评估。
在本研究中，共有24名健康的年轻受试者（16名男性，8名女性）按照30小时睡眠-觉醒时间表生活19至23天，或按照28小时睡眠-觉醒时间表生活33至36天；这两种时间表都会导致受试者的睡眠-觉醒周期与其内源性昼夜节律起搏器之间不同步。在所有规定的清醒时段，分别每2小时和每20分钟使用两种视觉模拟量表对主观情绪进行评估。每个数据点都对应一个昼夜节律相位和自醒来后经过的时间间隔，并对情绪的昼夜节律和觉醒依赖性波动进行评估。
观察到情绪随昼夜节律相位有显著变化，但未发现先前觉醒时长有可靠的主要影响。昼夜节律和觉醒依赖性波动之间存在统计学上显著的相互作用；当分析仅限于特定的昼夜节律相位时，情绪会随着先前觉醒时长的增加而改善、恶化或保持稳定。
这些结果表明，在健康的年轻受试者中，主观情绪受到昼夜节律相位和先前觉醒时长的复杂且非累加性相互作用的影响。这种相互作用的性质使得睡眠-觉醒周期时间的适度变化可能会对后续情绪产生深远影响。
