Untersuchung des hippokampo-neokortikalen Dialogs im deklarativen Gedächtnis mittels funktioneller Magnetresonanztomographie (fMRT)

事实和事件的记忆，即陈述性记忆，主要依赖于两个大脑结构：海马体和新皮层。大量研究表明，新的陈述性记忆的获取和检索依赖于海马体。然而，经过一段时间后，记忆轨迹变得独立，表明某种信息传递。最近，睡眠对这种记忆痕迹转移的重要性得到了广泛的讨论。特别是慢波睡眠被认为是通过重新激活那些在学习过程中活跃的神经网络来驱动这种信息传递。这里描述的实验旨在发现人类大脑活动中海马体-新皮层对话的相关关系。第一阶段的研究着眼于在睡眠后回忆单词表时海马和新皮层活动的变化，并将其与清醒后的回忆进行比较。此外，海马体-新皮层信息传递的动力学将通过药理操纵胆碱能神经传递而改变。活动将通过功能磁共振成像和脑电图（EEG）记录。在第二阶段，睡眠期间的大脑活动也将被记录下来，为人类海马体-新皮层对话模型提供直接证据。

Memory for facts and events, i.e. declarative memory, relies mainly on two brain structures: the hippocampus and the neocortex. Numerous studies have shown that acquisition and retrieval of new declarative memories depends on the hippocainpus. After some time, however, the memory trace becomes independent of it, indicating some kind of information transfer. Recently, the irnportance of sleep for this transfer of the memory trace has been discussed extensively. Especially slow-wave sleep is thought to drive this information transfer by reactivation of those neuronal networks that were active during learning. The experiments described here are aimed at finding correlates of this hippocampal-neocortical dialogue in human brain activity. The studies in phase I look at changes in hippocampal and neocortical activity during word list recall after sleep as compared to recall after periods of wakefulness. In addition, the dynamics of the hippocampal-neocortical information transfer will be modified experimentally by pharmacological manipulation of cholinergic neurotransmission. Activity will be recorded by means of fMRI and electroencephalography (EEG) recording. In phase II, brain activity during sleep will also be recorded to provide direct evidence for the model of a hippocampal-neocortical dialogue in humans.