High-Resolution fMRI of Medial Temporal Lobe Mechanisms in Declarative Memory

陈述性记忆中内侧颞叶机制的高分辨率功能磁共振成像

• 批准号: 7755357
• 负责人: Anthony D Wagner
• 金额: $ 38.53万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-02-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7755357
• 关键词: Address; Alzheimer' s Disease; Anterior; Attention; Clinical; Code; Concept Formation; Coupling; Data; Dependence; Discrimination; Elements; Event; Familiarity; Functional Imaging; Functional Magnetic Resonance Imaging; Functional disorder; Goals; Hippocampal Formation; Hippocampus (Brain); Human; Individual; Knowledge; Learning; Left; Medial; Mediating; Memory; Memory impairment; Methods; Nature; Organism; Outcome; Pattern; Performance; Population; Primates; Process; Relative (related person); Research; Research Personnel; Resolution; Response to stimulus physiology; Retrieval; Role; Schizophrenia; Sensory; Signal Transduction; Source; Stimulus; Structure; Temporal Lobe; Testing; Translating; Visual; base; blood oxygen level dependent; dentate gyrus; directed attention; experience; flexibility; forgetting; imaging modality; indexing; insight; memory encoding; mild neurocognitive impairment; novel; programs; relating to nervous system; research study; response; segregation; selective attention; theories

DESCRIPTION (provided by applicant): Declarative memory permits an organism to bridge the past with the present, providing information about prior events that serves to inform present decisions and action. Declarative memory critically depends on the medial temporal lobe (MIL), which is composed of the hippocampal formation (dentate gyrus, fields of cornu Ammonis, and subiculum) and the surrounding entorhinal, perirhinal, and parahippocampal cortices. Though decades of research have aimed to characterize the role of MIL in declarative memory, fundamental questions remain regarding the functional contributions of specific MTL substructures. Recent advances in functional imaging have now made it possible to begin to address these questions in humans. The proposed research will use high-resolution functional MRI and anatomically-based analysis methods to delineate the role of specific MTL cortical and hippocampal subfields in declarative memory. The proposed experiments will test anatomically-informed theory-driven hypotheses regarding the nature of declarative memory and its dependence on MTL function. Expts 1-3 will examine novelty-encoding processes in the anterior/posterior and coronal axes of MTL, focusing on whether content-sensitive encoding effects are present within distinct MTL cortices and hippocampal subfields. Expts 4-9 will explore the function of MTL substructures and their interactions during declarative memory encoding and retrieval, focusing on decomposition of mechanisms that support conjunctive and item memory. Expts 10-12 will test hypotheses about the nature of MTL retrieval mechanisms signaling item familiarity and temporal recency, including their dependence on study- test perceptual similarity. Expts 13-14 will examine how hippocampal and MTL cortical encoding mechanisms that encode item and conjunctive memories are impacted by goal-directed attention, including attention-dependent enhancement and suppression of MTL responses. The basic knowledge to be gained from this programmatic effort to test theory-driven hypotheses of declarative memory and MTL substructure function promises to yield new insights into the nature of learning and memory impairments in clinical populations. Declarative memory deficits accompany a number of clinical conditions, including schizophrenia, mild cognitive impairment, and Alzheimer's disease. We will directly translate the obtained outcomes to inform our collaborative studies of MTL dysfunction in schizophrenia.

描述（由申请人提供）：陈述性记忆允许有机体将过去与现在联系起来，提供有关先前事件的信息，这些信息用于告知当前的决定和行动。陈述性记忆主要依赖于内侧颞叶（MIL），它由海马结构（齿状回，氨角区和下托）和周围的内嗅，嗅周和海马旁皮质组成。虽然几十年的研究旨在描述MIL在陈述性记忆中的作用，但关于特定MTL子结构的功能贡献的基本问题仍然存在。功能成像的最新进展使我们有可能开始在人类中解决这些问题。拟议的研究将使用高分辨率的功能磁共振成像和解剖学为基础的分析方法来描绘特定的MTL皮质和海马子字段在陈述性记忆中的作用。拟议的实验将测试解剖学上知情的理论驱动的假设，陈述性记忆的性质和它的依赖MTL功能。摘要1-3将检查新奇的编码过程中的前/后和冠状轴的MTL，集中在内容敏感的编码效果是否存在于不同的MTL皮质和海马子字段。练习4-9将探讨MTL子结构的功能及其在陈述性记忆编码和提取过程中的相互作用，重点是支持连接记忆和项目记忆的机制的分解。练习10-12将测试关于MTL提取机制的性质的假设，这些机制发出项目熟悉度和时间近因的信号，包括它们对学习测试感知相似性的依赖。练习13-14将研究海马和MTL皮质编码机制，编码项目和连接记忆的影响目标导向的注意，包括注意依赖性增强和抑制MTL反应。从这个程序性的努力，以测试理论驱动的假设陈述性记忆和MTL子结构功能的基础知识有望产生新的见解的性质，学习和记忆障碍的临床人群。陈述性记忆缺陷伴随许多临床病症，包括精神分裂症、轻度认知障碍和阿尔茨海默病。我们将直接翻译所获得的结果，为我们的精神分裂症MTL功能障碍的合作研究提供信息。