The role of memory strength for processes of sleep-associated memory consolidation

虽然最近的研究结果表明，睡眠相关的记忆巩固过程可以稳定记忆，但尚不清楚这种巩固是否会随着记忆表征的最基本特征之一而变化，即，记忆的初始强度这个项目的目的是通过研究记忆强度对记忆巩固的作用，从行为学和神经科学的角度来填补这一经验空白。在13个实验中，记忆强度将被操纵使用有意和附带的编码程序;强度的有意操纵将被检查在配对联想任务和列表学习任务中，并将通过学习诱导和检索诱导的强化来实现;强度的附带操纵将被调查在列表学习任务中，通过使用不同的定向任务。在行为上，记忆巩固的效果将通过调查时间依赖性遗忘和记忆的干扰敏感性来测量。在神经元方面，脑电图（EEG）将用于研究编码强度的操纵如何改变初始记忆形成的神经相关性，并在编码后以及12小时的睡眠或清醒后改变检索处理。此外，睡眠脑电图将被用来检查睡眠机制，认为是直接参与重新激活和重建新形成的记忆。研究结果将为记忆强度在睡眠相关记忆巩固中的作用提供第一个整体图景。

While recent findings demonstrate that processes of sleep-associated memory consolidation can stabilize memories, it is unclear whether such consolidation varies with one of the most basic features of memory representations, i.e., memories’ initial strength. The aim of this project is to fill this empirical gap by examining the role of memory strength for memory consolidation, behaviorally and neuroscientifically. Across 13 experiments, memory strength will be manipulated using intentional and incidental encoding procedures; intentional manipulations of strength will be examined in the paired associate task and the list learning task and will be implemented by study-induced and retrieval-induced strengthening; incidental manipulations of strength will be investigated in the list learning task by using different orienting tasks. Behaviorally, effects of memory consolidation will be measured via investigations of time-dependent forgetting and memories’ interference susceptibility. Neuronally, electroencephalography (EEG) will be used to study how manipulations of encoding strength change the neural correlates of initial memory formation and change retrieval processing right after encoding as well as following 12 hours of sleep or wakefulness. In addition, sleep EEG will be employed to examine sleep mechanisms believed to be directly involved in the reactivation and restructuring of newly formed memories. The results will provide a first overall picture on the role of memory strength for sleep-associated memory consolidation.