HEBB MARR NETWORKS THE HIPPOCAMPUS AND SPATIAL MEMORY

描述（改编自申请人的摘要）：本项目的目的是 理解这些现象背后的机制和计算原理 依赖于功能性海马体（HC）的记忆编码， 随后整合到独立于HC的长期存储中， 新皮质（NC）。 这是改善记忆的先决条件 由发育异常、疾病、创伤、衰老引起的障碍 或者滥用药物 工作假设是，长期的功能 记忆是从过去的经验中构建内部表征， 反映了环境的统计数据，因此， 允许适应性泛化和适当的反应。 这样的学习 需要重复、交错地暴露于要存储的物品， 每次试验都对突触进行小的调整 尝试存储新的 在这样存储器中同时存储所有信息导致“灾难性干扰” 物品已存储;但是，生存通常需要添加新物品 现有的范畴结构，只有一个或几个经验。 假设HC生成并存储 这些事件的空间背景，与 事件的各个组成部分在其各自的NC领域的时间 的经验。 通过自发地重新激活这些存储的上下文， HC有助于以连贯的方式恢复原始模式， 时尚，从而提供了所需的“训练试验” 而系统是“离线”的。 这提供了一个框架， HC损伤后的时间分级逆行性遗忘现象， 以及记忆巩固是如何发生的。 使用同时 从50-150个神经元的记录中，已经表明群体编码 新的环境在探索过程中迅速发展， 在集体活动中可以观察到最近的事件和事件序列 在安静清醒和慢波睡眠期间，HC和NC中的神经元的数量。 建议的记录研究涉及该理论的具体方面： 是否离线重新激活记忆痕迹的鲁棒性 与随后的表现相关;是否有更多的远程记忆 在离线期间与较新的交叉;是否有 记忆再激活的逆行梯度;哪些行为状态是最重要的 有利于再活化;在NC中也发生再活化的程度 在离线期间; NC和HC重新激活是否反映了 最近的经验相同;以及是否需要职能性人道主义协调员， 重新激活NC中的近期记忆。 最后，建议测试 理论，通过在HC中施加分布的电活动模式， 空间结构化的电刺激在空间 信息和离线期间。

DESCRIPTION (Adapted from applicant's abstract): The aim of this project is to understand the mechanisms and computational principles underlying the encoding of memories that depend on a functional hippocampus (HC), and their subsequent consolidation into HC-independent, long-term storage, presumably in the neocortex (NC). This is a prerequisite to ameliorating memory disorders resulting from developmental abnormalities, disease, trauma, aging or drug abuse. The working hypothesis is that the function of long-term memory is to construct, from past experience, internal representations that reflect the statistical regularities of the environment, and which thus permit adaptive generalization and appropriate responses. Such learning requires repeated, interleaved exposure to the items to be stored, with small adjustments to the synapses on each trial. Attempts to store new information all at once in such a memory lead to "catastrophic interference" with items already stored; however, survival often requires adding new items to the existing categorical structure, with only one or a few experiences. It is hypothesized that HC generates and stores compact representations of the spatial contexts of such events, which become associated with the individual components of the events in their respective NC areas at the time of the experience. By spontaneously reactivating these stored contexts, the HC facilitates the reinstatement of the original patterns in a coherent fashion throughout NC, and thus provides the required "training trials" while the system is "off-line". This provides a framework for understanding the phenomenon of temporally graded retrograde amnesia following HC damage, and why and how memory consolidation takes place. Using simultaneous recordings from 50-150 neurons, it has been shown that population-codes for novel environments develop rapidly during exploration, and that traces of recent events and event-sequences can be observed in the collective activity of neurons in both HC and NC during quiet wakefulness and slow-wave sleep. The proposed recording studies address specific aspects of the theory: whether the robustness of off-line reactivation of memory traces is correlated with subsequent performance; whether more remote memories are interleaved with newer ones during off-line periods; whether there is a retrograde gradient of memory reactivation; which behavioral states are most conducive to reactivation; to what extent reactivation also occurs in NC during the off-line periods; whether NC and HC reactivations reflect the same recent experiences; and whether a functional HC is necessary for reactivation of recent memory in NC. Finally, it is proposed to test the theory by imposing distributed patterns of electrical activity in HC using spatially structured electrical stimuli both during acquisition of spatial information and during off-line periods.