Mosko S, Richard C, McKenna J
Department of Neurology, University of California Irvine Medical Center, Orange, California 92868, USA.
Pediatrics. 1997 Nov;100(5):841-9. doi: 10.1542/peds.100.5.841.
Normative values for infant sleep architecture have been established exclusively in the solitary sleeping environment. However, most of the world's cultures practice some form of parent-infant cosleeping. In addition, no previous polysomnographic studies in infants examined the frequency of electroencephalogram (EEG) arousals. This is the first study to assess (a) EEG arousals in infants and their relationship to sleep stages; (b) the impact on arousals of mother-infant bed sharing; and (c) the temporal overlap of infant with maternal arousals during bed sharing.
Three nights of polysomnography were performed in 35 breastfeeding mother-infant pairs when the infants were 11 to 15 weeks old. An adaptation night was followed by one bed sharing night and one solitary sleeping night. Twenty infants had been bed sharing since birth and 15 were routine solitary sleepers. Both epochal awakenings (EWs), based on 30-second epoch scoring of sleep-wake stages, and more transient arousals (TAs) >/=3 seconds were quantified.
Stage 3-4 sleep was associated with a striking paucity of EWs and TAs compared with stages 1-2 or rapid eye movement sleep. Bed sharing facilitated EWs and TAs selectively during stage 3-4 sleep. EWs from stage 3-4 sleep were more frequent on the bed sharing night than on the solitary night in both infant groups. Routinely bed sharing infants also exhibited more frequent TAs in stage 3-4 than the routine solitary sleepers in both conditions. In both groups, the number of infant arousals (EWs + TAs) that overlapped the mother's was doubled during bed sharing, with infant arousals leading most often.
Mother-infant bed sharing promotes infant arousals. Together with a previous report that bed sharing reduces stage 3-4 sleep, this suggests that normative values for infant sleep must be interpreted within the context of the sleeping environment in which they were established. Given that arousability is diminished in stage 3-4, we speculate that, under otherwise safe conditions, the observed changes in stage 3-4 sleep and arousals associated with bed sharing might be protective to infants at risk for SIDS because of a hypothesized arousal deficit. The responsivity of the mother to infant arousals during bed sharing might also be protective.
婴儿睡眠结构的规范值仅在单独睡眠环境中确立。然而，世界上大多数文化都存在某种形式的母婴同床共眠。此外，此前尚无针对婴儿的多导睡眠图研究检测过脑电图（EEG）觉醒的频率。这是第一项评估以下内容的研究：（a）婴儿的EEG觉醒及其与睡眠阶段的关系；（b）母婴同床对觉醒的影响；（c）同床期间婴儿与母亲觉醒的时间重叠情况。
对35对母乳喂养的母婴在婴儿11至15周龄时进行三晚的多导睡眠图监测。先有一晚适应期，随后是一晚同床共眠和一晚单独睡眠。20名婴儿自出生起就同床共眠，15名是常规单独睡眠者。基于对睡眠-觉醒阶段30秒时段的评分，对时段性觉醒（EWs）以及持续时间≥3秒的更短暂觉醒（TAs）均进行了量化。
与1-2期或快速眼动睡眠相比，3-4期睡眠的EWs和TAs明显较少。同床共眠在3-4期睡眠期间选择性地促进了EWs和TAs。在两个婴儿组中，3-4期睡眠的EWs在同床共眠夜比单独睡眠夜更频繁。在两种情况下，习惯同床共眠的婴儿在3-4期的TAs也比习惯单独睡眠的婴儿更频繁。在两个组中，同床共眠期间与母亲觉醒重叠的婴儿觉醒次数（EWs + TAs）增加了一倍，且婴儿觉醒最为常见。
母婴同床共眠会促进婴儿觉醒。此前有报告称同床共眠会减少3-4期睡眠，这表明婴儿睡眠的规范值必须在其确立的睡眠环境背景下进行解读。鉴于3-4期的可唤醒性降低，我们推测，在其他条件安全的情况下，观察到的与同床共眠相关的3-4期睡眠和觉醒变化可能对因假设的唤醒不足而有患婴儿猝死综合征风险的婴儿具有保护作用。同床共眠期间母亲对婴儿觉醒的反应性也可能具有保护作用。
