Hippocampal-Neocortical Interactions During Naturalistic Learning

项目总结 情节记忆是我们个人过去的表现，固定在时间和空间上。插曲 癫痫、创伤性脑损伤和阿尔茨海默病等神经系统疾病的记忆损害 大大限制了患者独立工作和生活的能力。在日常生活中，大脑必须处理 连续的现在形成对过去的离散记忆。这种将经验解析为有意义的能力 语块被称为事件分段，是人类情景记忆的基础。功能神经成像 研究表明，海马体和后皮质网络显示出同时增加的 事件边界和结尾的活动，但支持这一划分的神经事件尚不清楚。 许多啮齿动物研究表明，神经振荡--特别是theta、伽马和尖波--会产生涟漪 (SWR)活动-在这些关键时刻协调海马区-新皮质的相互作用。 我们的长期目标是发现大脑是如何组织和巩固在 自然主义的环境。这项建议的目的是测量海马区-新皮质的动力学。 在情节记忆中的关键时刻。我们的中心假设是海马体在 通过增强的theta-Gamma活动分割和合并从新大脑皮层传递的信息 事件边界和观看后休息期间更高的SWR率。为了检验这些主要假设，我们将 获取接受侵入性监测的癫痫患者的颅内脑电(IEEG)记录，用于外科手术 治疗。受试者将观看一系列具有叙事结构和序列的短片，然后 被要求召回选定的内容。在这个项目成功完成后，我们将完成 目的：1.测量海马区和中性粒细胞对事件分割的相对贡献 在看电影的时候。目的2.测量海马区在记忆巩固中的作用。 观看休息。目的3.通过电信号测试海马区进行事件分割的必要性 刺激(ES)。 这一建议代表了认知神经科学在记忆方面的先前工作的重大进步 使用iEEG来确定与记忆自然事件有关的海马区-新皮质振荡。 本项目在理念和方法上具有创新性，主要体现在以下几个方面：(1)利用短片研究人类 情景记忆；(2)啮齿动物记忆中的关键神经生理学发现向人类情景记忆的转化 记忆；以及(3)确定海马体在事件分割和记忆中的必要性 通过ES进行性能测试。我们的发现将推动以机制为导向的评估方法和 治疗癫痫和创伤性脑损伤等神经精神障碍患者的记忆功能障碍。

PROJECT SUMMARY Episodic memories are representations of our personal past, anchored to time and space. Episodic memory impairments in neurological disorders like epilepsy, traumatic brain injury, and Alzheimer’s Disease significantly limit patients’ ability to work and live independently. In everyday life, the brain must process the continuous present to form discrete memories of the past. This ability to parse experience into meaningful chunks, termed event segmentation, is foundational to human episodic memory. Functional neuroimaging studies suggest that the hippocampus and a posterior cortical network demonstrate a simultaneous increase in activity at event boundaries and endings, but the neural events supporting this demarcation are unknown. Numerous rodent studies suggest that neural oscillations—particularly theta, gamma, and sharp-wave ripple (SWR) activity—coordinate hippocampal-neocortical interactions at these critical junctures. Our long-term goal is to discover how the brain organizes and consolidates continuous experience under naturalistic circumstances. The objective of this proposal is to measure the hippocampal-neocortical dynamics at key moments in episodic memory. Our central hypothesis is that the hippocampus plays a critical role in segmenting and consolidating information delivered from the neocortex, via enhanced theta-gamma activity at event boundaries and increased SWR rate during post-viewing rest. To test these main hypotheses, we will obtain intracranial EEG (iEEG) recordings from epilepsy patients undergoing invasive monitoring for surgical treatment. Subjects will view a series of short films that possess a narrative structure and sequence, then will be asked to recall selected content. Upon successful completion of this project, we will accomplish the following aims: Aim 1. To measure the relative contributions of hippocampus and PMN to event segmentation during film viewing. Aim 2. To measure the hippocampal contribution to memory consolidation during post- viewing rest. Aim 3. To test the necessity of the hippocampus for event segmentation through electrical stimulation (ES). This proposal represents a significant advance from prior work in the cognitive neuroscience of memory by using iEEG to determine the hippocampal-neocortical oscillations involved in remembering naturalistic events. This project is innovative in concept and method because of (1) the use of short films to investigate human episodic memory; (2) the translation of key neurophysiological findings in rodent memory to human episodic memory; and (3) establishing the necessity of the hippocampus in event segmentation and memory performance through ES. Our findings will advance mechanism-guided approaches to the assessment and remediation of memory dysfunction in neuropsychiatric disorders such as epilepsy and traumatic brain injury.