Content representation in the human medial temporal lobe

人类内侧颞叶的内容表征

• 批准号: 8457876
• 负责人: Jackson Chit Liang
• 金额: $ 3.62万
• 依托单位: UNIVERSITY OF TEXAS AT AUSTIN
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-12-22 至 2014-12-21
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8457876
• 关键词: Address; Affect; Alzheimer' s Disease; Anatomy; Brain; Categories; Classification; Code; Cues; Data; Detection; Discrimination; Dissociation; Episodic memory; Event; Face; Functional Magnetic Resonance Imaging; Future; Hippocampus (Brain); Human; Imagery; Impairment; Individual; Judgment; Knowledge; Learning; Link; Medial; Mediating; Memory; Modeling; Multivariate Analysis; Nature; Pattern; Performance; Post-Traumatic Stress Disorders; Research; Research Proposals; Resolution; Retrieval; Role; Schizophrenia; Source; Stimulus; Structure; System; Techniques; Temporal Lobe; Testing; Visuospatial; Work; base; experience; forgetting; indexing; insight; memory process; memory recognition; memory retrieval; neural patterning; novel; novel strategies; relating to nervous system; research study; response; sound; success; theories; visual object processing

DESCRIPTION (provided by applicant): The fundamental question underlying memory function is how information is represented in the brain. Current models suggest that the content of our experiences might be represented by anatomically distinct brain structures, and the nature of those representations might change as they are transformed from novel information to stored memories. Although the central role of the medial temporal lobe (MTL) in episodic memory-memory for individual events-is well established, the nature of content representation in the MTL is still unclear. The anatomical organization of the MTL suggests that individual MTL subregions make unique contributions to the encoding of episodic memories based on content. However, evidence for these distinctions has been mixed. This research proposal will combine high-resolution functional magnetic resonance imaging (fMRI) and high-dimensional analyses to reveal the MTL subregional contributions to content-sensitive encoding with greater precision than previously possible. Experiment 1 will test the hypothesis that MTL cortical subregions and hippocampus make unique responses to different forms of content to support item- level encoding. A novel multivariate analytical technique will allow us to assess the information carried by subthreshold activity. It will also reveal the developing nature of content representations as they are successfully encoded. Experiment 2 will test the hypothesis that specific categories of content representation are reinstated to support memory for episodic details. We will also consider the responses of hippocampal subfields to determine their computational role in mediating encoding and reinstatement. Experiment 3 will test the hypothesis that content representations are reactivated to help anticipate the future. Multivariate analysis of patterned activation during timepoints before expected events will test whether they carry information predicting the content of those events. This research will help identify the nature of content representation in the MTL, giving us a clearer picture of how we remember the world around us. It will also give us insight into the possible functional role of content codes in MTL. Understanding these open questions through the completion of the proposed project will help us identify the underlying nature of impairment from conditions that affect MTL function or structure, including Alzheimer's disease, post-traumatic stress disorder, and schizophrenia. ) PUBLIC HEALTH RELEVANCE: The proposed research investigates how medial temporal lobe structures support memory for the content of experienced events. It will also reveal how our memories are reactivated to make sense of current events or predict the future. Understanding these mechanisms will help us identify the underlying nature of impairment from conditions that affect MTL function or structure, including Alzheimer's disease, post-traumatic stress disorder, and schizophrenia.)

描述（由申请人提供）：记忆功能的基本问题是信息如何在大脑中表示。目前的模型表明，我们的经历的内容可能由解剖学上不同的大脑结构来表示，并且这些表示的性质可能会随着它们从新信息转变为存储的记忆而改变。尽管内侧颞叶 (MTL) 在情景记忆（单个事件的记忆）中的核心作用已得到充分证实，但 MTL 内容表征的性质仍不清楚。 MTL 的解剖结构表明，各个 MTL 子区域对基于内容的情景记忆编码做出了独特的贡献。然而，这些区别的证据好坏参半。该研究提案将结合高分辨率功能磁共振成像 (fMRI) 和高维分析，以比以前更高的精度揭示 MTL 次区域对内容敏感编码的贡献。实验 1 将测试 MTL 皮质分区和海马体对不同形式的内容做出独特反应以支持项目级编码的假设。一种新颖的多变量分析技术将使我们能够评估阈下活动所携带的信息。它还将揭示内容表示在成功编码时的发展性质。实验 2 将测试以下假设：恢复特定类别的内容表示以支持情景细节的记忆。我们还将考虑海马子区域的反应，以确定它们在介导编码和恢复中的计算作用。实验 3 将测试内容表征被重新激活以帮助预测未来的假设。多变量 对预期事件之前的时间点期间的模式激活进行分析将测试它们是否携带预测这些事件内容的信息。这项研究将有助于确定 MTL 内容表征的本质，让我们更清楚地了解我们如何记住周围的世界。它还将使我们深入了解内容代码在以下方面可能的功能作用： MTL。通过完成拟议项目来了解这些悬而未决的问题将有助于我们确定影响 MTL 功能或结构的疾病（包括阿尔茨海默氏病、创伤后应激障碍和精神分裂症）造成损害的根本性质。 ） 公共健康相关性：拟议的研究调查了内侧颞叶结构如何支持对经历事件内容的记忆。它还将揭示我们的记忆如何被重新激活以理解当前事件或预测未来。了解这些机制将有助于我们识别影响 MTL 功能或结构的疾病（包括阿尔茨海默病、创伤后应激障碍和精神分裂症）造成的损伤的根本性质。）