Oscillatory mechanisms of context dependent cognitive maps in human memory

项目总结/摘要 记忆是如何引导我们在特定的地点和情境中做出选择的？我们的大脑是如何完成 这个吗？记忆、导航和上下文相关的决策对于适应性人类行为至关重要 并且在几种神经和精神疾病中受损。该提案旨在确定基本的 调节人类大脑中依赖于上下文的记忆表征的机制 用于临床人群记忆增强的精细治疗工具。更具体地说，这项建议将 研究背景依赖记忆编码和提取的神经基础，使我们能够 根据具体情况灵活应变。有影响力的人脑成像和病变研究 已经发现海马体（HPC）和内侧前额叶皮层（mPFC），沿着他们的大脑皮层， 交互，是记忆和导航计算发生的地方。然而，这些研究都很差。 时间分辨率且不直接测量电活动。因此，我们不明白 依赖性记忆是在人类中形成和恢复的。拟议的实验将利用直接的人类 在接受侵入性癫痫发作监测的癫痫患者中，HPC和mPFC的脑记录产生新的 深入了解人类记忆的电生理学基础。患者进行情境依赖性学习 和记忆任务，其中对象与取决于上下文的不同奖励相关联。任务 嵌入在虚拟环境中，能够比较空间导航和 联想记忆我们假设，同步，“相位编码”振荡活动内和之间 HPC和mPFC支持上下文相关存储器。旨在识别独特和重叠的 电生理机制介导的背景依赖的代表，这一建议很可能是 改变我们对人类大脑如何协调其活动以适应人类的理解。 行为这项工作也将揭示人类大脑如何利用复杂的，依赖于上下文的 关联，以提供对几个临床人群中介导损伤的假定机制的深入了解。

Project Summary/Abstract How does memory guide our choices in particular locations and contexts? How does our brain accomplish this? Memory, navigation, and context dependent decision-making are essential for adaptive human behavior and are impaired in several neurological and psychiatric disorders. This proposal aims to identify the basic mechanisms mediating context dependent memory representations in the human brain towards advancing refined therapeutic tools for memory enhancement in clinical populations. More specifically, this proposal will investigate the neural basis of context dependent memory encoding and retrieval, behavior that enables us to flexibly act in the world according to particular situations. Influential human brain imaging and lesion studies have identified that the hippocampus (HPC) and the medial prefrontal cortex (mPFC), along with their interactions, are where memory and navigational computations take place. However, these studies have poor temporal resolution and do not directly measure electrical activity. Thus, we don't understand how context dependent memories are formed and retrieved in humans. The proposed experiments will utilize direct human brain recordings from HPC and mPFC in epilepsy patients undergoing invasive seizure monitoring to yield new insight into the electrophysiological basis of human memory. Patients perform a context dependent learning and memory task in which objects are associated with different rewards depending on context. The task is embedded in a virtual environment, enabling comparisons of neural signatures of both spatial navigation and associative memory. We hypothesize that synchronous, “phase coded” oscillatory activity within and between the HPC and mPFC supports context dependent memory. Aiming to identify the unique and overlapping electrophysiological mechanisms mediating context dependent representations, this proposal is likely to transform our understanding of how the human brain coordinates its activity in the service of adaptive human behavior. This work will also shed new light on how the human brain utilizes complex, context dependent associations to provide insight into putative mechanisms mediating impairments in several clinical populations.