Relationship of semantic representations to connectivity-based brain architecture

语义表示与基于连接的大脑结构的关系

• 批准号: 8911209
• 负责人: Sonya H Mehta
• 金额: $ 3.89万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-16 至 2017-06-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8911209
• 关键词: Accounting; Address; Animals; Anterior; Aphasia; Architecture; Autistic Disorder; Base of the Brain; Binding; Categories; Classification; Clinical; Data; Data Analyses; Dementia; Developmental reading disorder; Diffusion Magnetic Resonance Imaging; Disease Progression; Event; Face; Functional Magnetic Resonance Imaging; Geometry; Goals; Imaging Techniques; Individual; Knowledge; Language; Left; Light; Link; Measures; Mediating; Names; Nature; Participant; Patients; Pattern; Persons; Play; Population; Probability; Research; Retrieval; Role; Schizophrenia; Semantics; Specificity; Stimulus; Structure; Techniques; Temporal Lobe; Testing; Training; base; lexical retrieval; neuroimaging; public health relevance; research study; response; social; theories

 DESCRIPTION (provided by applicant): Decades of research provide evidence that the left anterior temporal lobe (ATL) plays a critical role in the retrieval of semantic (conceptual or word meaning) representations during naming. However, the nature of these representations and how they relate to the functional organization of the ATL remains elusive. The goal of this project is to combine newly emergent imaging techniques (multi-voxel pattern analysis fMRI and diffusion MRI-based cortical parcellation) to explicitly investigate the organization of semantic knowledge support within the left ATL. Specifically, we will focus on addressing the prevailing theories that the left ATL 1) supports domain general (i.e. category-independent) representations, 2) supports representations specifically for persons (or social entities), or 3) supports representations for unique entities (e.g. famous faces or landmarks). We hypothesize that there are functional subdivisions within the ATL, with different cortical sectors supporting each of these representations. Furthermore, we hypothesize that the functional subdivisions within the ATL will have distinct patterns of anatomical connectivity patterns (reflecting the nature of information binding), and that connectivity-defined cortical regions are an appropriate level of organization to assess semantic structure. To test our hypotheses, we will analyze data from two event-related fMRI experiments in which participants named entities from several different conceptual categories (animals, famous faces, unique TV characters, and landmarks). We will use diffusion MRI data to parcellate the left ATL into sub-regions based on the homogeneity of their anatomical connectivity profiles and multi-voxel pattern analysis fMRI to interrogate the information content in order to reveal the semantic structure of the representations within each parcel. These approaches have the potential to shed light on the nature of semantic representations and to establish a link between their emergence and underlying connectivity-based brain architecture. The findings and approaches proposed here have significant potential for application to clinical populations with altered semantic representations like degenerative dementia, or schizophrenia, and altered language abilities like aphasia, autism and developmental dyslexia. Moreover, our theoretical and methodological framework offers a means to measure the integrity of semantic knowledge in patients and to track disease progression, and treatment or training responses.

 描述（由申请人提供）：数十年的研究提供的证据表明，左前颞叶 (ATL) 在语义（概念或单词）检索中发挥着关键作用。 然而，这些表示的本质以及它们与 ATL 功能组织的关系仍然难以捉摸，该项目的目标是新结合新兴成像技术（多体素模式分析 fMRI 和扩散 MRI）。具体来说，我们将重点关注左 ATL 1) 支持领域通用（即类别无关）表示的流行理论， 2）支持专门针对个人（或社会实体）的表示，或 3）支持独特实体（例如著名的面孔或地标）的表示。我们认为 ATL 中有功能细分，不同的皮质部分支持这些表示。此外，我们追求 ATL 内的功能细分将具有不同的解剖连接模式（反映信息绑定的本质），并且连接定义的皮层区域是评估语义的适当组织级别。为了检验我们的假设，我们将分析两个与事件相关的功能磁共振成像实验的数据，其中参与者从几个不同的概念类别（动物、著名面孔、独特的电视角色和地标）命名实体，我们将使用扩散 MRI 数据进行分区。根据其解剖连接剖面的同质性和多体素模式分析功能磁共振成像，将左 ATL 分为子区域，以询问信息内容，以揭示每个地块内表示的语义结构，这些方法有可能揭示这一点。语义表征的本质，并在它们的出现和潜在的基于连接的大脑结构之间建立联系，这里提出的发现和方法对于具有退行性痴呆或精神分裂症等语义表征以及语言能力等的临床人群具有巨大的应用潜力。此外，我们的理论和方法框架提供了一种衡量患者语义知识完整性并跟踪疾病进展以及治疗或训练反应的方法。