Longitudinal study of sleep physiology and function across toddlerhood

项目总结 蹒跚学步的孩子们有一半的时间在睡觉。虽然众所周知，睡眠有助于儿童学习，但无论这一点 早期发育过程中的功能变化尚不清楚。最近的理论研究表明，关键的转变 睡眠的认知功能在这个年龄段出现。因此，需要对幼儿时期的睡眠进行纵向研究。 这项拟议的研究的具体目标是检查夜间睡眠的纵向变化。 16~31月龄儿童生理和睡眠认知功能的研究在这样做时，我们将解决两个问题 建议改变学步儿童的睡眠功能。首先，海马体发育的关键变化是 建议将18个月的睡眠功能与24个月的睡眠功能相比较。第二，中国的模式 大脑新陈代谢表明，睡眠的功能，特别是快速眼动睡眠，与28个月相比发生了变化 至那30个月。为了测试这些预测的睡眠功能转折点，我们招募了16岁的婴儿 或21个月，分3波评估睡眠前后的陈述性记忆，间隔为5 月份。多导睡眠图将被用来理解睡眠益处背后的生理机制。 第一个目标是研究过夜睡眠对记忆的益处是否会在学步阶段发生变化。具体来说， 我们将考虑睡眠相对于记忆唤醒结果的益处是否有变化 跨过蹒跚学步的童年。我们假设睡眠会在这个年龄范围内始终如一地保护记忆，但 随着时间的推移，记忆的衰退性会更小。目标2是检验快速眼动的贡献是否 而非快速眼动睡眠对记忆的影响超过了幼儿时期的睡眠。具体来说，我们将审查 NREM振荡和REM睡眠对睡眠相关记忆变化的预测贡献 蹒跚学步。假设2是睡眠过程中记忆的变化与睡眠纺锤波的耦合有关 以及缓慢的振荡，特别是这些节奏之间的相位耦合。这项工作将会有明确的 睡眠和发育科学领域的理论意义，因为我们试图测试 已经在这些领域获得了关注。区分这个年龄段的睡眠功能将提供关键的 对睡眠记忆潜在机制的洞察在任何年龄都会受益。这部作品具有翻译性 意义也很重大。具体来说，了解这个年龄段的睡眠生理和功能对 当这些过程受到损害时，识别和理解。此外，睡眠在记忆中的作用 承诺采取干预措施，改善学习延迟或康复。作为对睡眠的强烈理解 记忆中的角色最终将支持这种干预方法。

PROJECT SUMMARY Toddlers spend half their day sleeping. While it is known that sleep supports learning in childhood, whether this function changes across early development is unknown. Recent theoretical work suggests that critical transitions in sleep's cognitive function occur at this age. Thus, longitudinal studies of sleep across toddlerhood are needed. The specific objective of the proposed research is to examine longitudinal changes in overnight sleep physiology and sleep's cognitive function in children 16-31 months of age. In doing so, we will address two proposed changes in sleep function in toddlerhood. First, critical changes in hippocampal development are suggested to change sleep's function for those <18 months relative to those >24 months. Second, models of brain metabolism suggest that the function of sleep, particularly REM sleep, changes from <28 months relative to those >30 months. To test these predicted turning points in sleep function, we will recruit infants who are 16 or 21 months and assess declarative memory before and after overnight sleep in 3 waves, separated by 5 months. Polysomnography will be used to understand the physiological mechanism underlying sleep benefits. Aim 1 is to examine whether memory benefits of overnight sleep change across toddlerhood. Specifically, we will consider whether there is a change in how beneficial sleep is relative to wake on memory outcomes across toddlerhood. We hypothesize that sleep will protect memories consistently across this age span but that memories will decay less over wake with development. Aim 2 is to examine whether the contribution of REM and non-REM sleep to memory change over sleep across toddlerhood. Specifically, we will examine predicted contributions of nREM oscillations and REM sleep to sleep-related memory changes across toddlerhood. Hypothesis 2 is that the change in memory over sleep is associated with coupling of sleep spindles and slow oscillations and, in particular, the phase coupling between these rhythms. This work will have clear theoretical significance for the fields of sleep and developmental sciences as we seek to test theories that have gained attention in those fields. Distinguishing the function of sleep across this age range will provide critical insight into mechanisms underlying sleep's memory benefit at any age. The work holds translational significance as well. Specifically, understanding sleep physiology and function at this age is critical for recognizing and understanding when these processes are impaired. Moreover, sleep's role in memory holds promise for interventions to improve learning delays or rehabilitation. As such a strong understanding of sleep's role in memory will eventually support such intervention approaches.