Collaborative Research: Hippocampal Development and Sleep-Dependent Memory Consolidation in Preschoolers

午睡有利于幼儿的学习和记忆。然而，孩子们在学前班的时候就不再打盹了。目前尚不清楚是应该鼓励学龄前儿童午睡，还是应该取消午睡，以便为早期学习提供更多时间。这项拟议研究的总体目标是研究睡眠和大脑发育在儿童早期记忆中的作用，特别是当儿童从午睡过渡时。这一提议的中心假设是，在这个过渡发育时期，与记忆相关的大脑区域的成熟导致更多的信息在不受干扰的情况下被保留在记忆中。这反过来又减少了频繁巩固的需要，这最终奠定了从小睡过渡的基础。这项研究将加深对睡眠如何有益于健康儿童的学习和记忆的理解，为健康的儿童保育和学前教育提供益处。睡眠依赖性记忆巩固被认为反映了记忆从海马体到大脑皮层的转移。虽然我们之前已经记录了幼儿睡眠依赖性巩固导致的记忆表现变化，但支持这一过程的神经机制尚未得到研究。这一空白是有问题的，因为记忆和海马体-皮层网络在这一时期都经历了显著的发育变化。我们的目标是确定大脑发育和睡眠生理学在儿童发育过程中记忆变化的机制途径。为了实现这一目标，我们将获得大脑结构、大脑功能、睡眠生理学和记忆的测量。我们假设，大脑和睡眠生理发育中与年龄相关的变化将导致更大、更强的记忆。同样，我们预计海马功能连接的增加将允许更有效的睡眠记忆转移，并将与慢波睡眠的变化有关。我们将使用模型来检验海马体结构变化先于海马体功能变化的假设；这些综合变化会导致睡眠模式的改变；改善睡眠会改善记忆力。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Naps benefit learning and memory in young children. However, children transition out of naps during preschool years. Whether naps should be encouraged in preschools, or eliminated to provide more time for early learning, is not clear. The overarching objective of this proposed research is to examine the role of sleep and brain development on memory during early childhood, specifically as children transition out of naps. The central hypothesis of this proposal is that maturation of memory-related brain regions during this transitional developmental period results in more information being retained in memory without interference. This in turn reduces the need for frequent consolidation, which ultimately underlies the transition out of naps. This research will deepen understanding of how sleep benefits learning and memory in healthy children, providing benefit to healthy child care, and pre-school education. Sleep-dependent memory consolidation is thought to reflect transfer of memories from the hippocampus to the cerebral cortex. Although we have previously documented changes in memory performance as a result of sleep-dependent consolidation in young children, the neural mechanisms supporting this process have yet to be examined. This gap is problematic as memory and the hippocampal-cortical network both undergo significant developmental change during this period. Our goal is to identify the mechanistic pathway through which brain development and sleep physiology underlie changes in memory during childhood development. To accomplish this, we will obtain measures of brain structure, brain function, sleep physiology, and memory. We hypothesize that age-related changes in the development of the brain and sleep physiology will result in larger and stronger memories. Likewise, we expect increased hippocampal functional connectivity to allow for more efficient memory transfer with sleep, and will be associated with changes in slow wave sleep. We will use models to test the hypothesis that changes in hippocampal structure will precede changes in hippocampal function; these combined changes will lead to changes in sleep patterns; and that improved sleep will improve memory.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.