Investigations of the dynamic nature of intrinsic brain networks

内在大脑网络的动态性质的研究

基本信息

批准号：
8425675
负责人：
Jessica R Cohen
金额：
$ 5.39万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-03-01 至 2014-02-28
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): The brain has an amazing ability to flexibly engage different functional networks based on the demands of a constantly changing environment. Sometimes forces acting on an intrinsic, baseline environment are transient, such as the dynamic cognitive demands of daily life. At other times they are longer term, and occasionally permanent, such as the changes that occur due to aging, brain damage, or psychiatric disorders. Recently there has been a focus on measuring the intrinsic functional connectivity of networks of brain regions during rest using functional MRI (fMRI). The application of graph theoretical tools taken from the field of mathematics to these intrinsic brain networks allows for the quantification of network properties, such as the degree to which groups of brain regions separate themselves into largely independent networks (or modules), and the identification of the role of individual brain regions, such as whether a region is integral for communication across multiple brain regions and networks, or whether a region limits its interactions to a small subset of brain regions within a single network. This proposal aims to extend this characterization of intrinsic brain networks to other contexts to assess the brain's potential for plasticity in different contexts. The proposed research, therefore, will investigate both the reconfiguration of global brain organization and the changing roles of individual brain regions from intrinsic network configuration in two different contexts: 1) disruption of functioning due to focal brain lesions, and 2) specific cognitive demands due to administration of different conditions of a cognitive task. METHOD: This research proposal will apply state-of-the-art methodologies and analyses to address the specific aims. The first experiment will analyze data that was collected from patients with focal brain lesions and age-matched healthy controls to assess the extent of network reconfiguration after brain damage. I hypothesize that adaptive network reconfiguration will occur if the role of intact tissue within the network that sustained te brain damage changes to be more similar to the role that the damaged tissue had in healthy, intrinsic brain organization. I predict that within-network adaptation is a more accurate manner of characterizing compensatory changes in brain organization than is focusing purely on intact tissue anatomically close to the damaged tissue (i.e., perilesional tissue) or on intact tissue in homologous regions in the undamaged (i.e., contralesional) hemisphere. The second experiment will examine the brain's ability to reconfigure in different cognitive contexts in healty young adults. I hypothesize that adaptive network reconfiguration will occur by changing network organization toward a single context-specific network made up of cognitively relevant regions and connections across separate intrinsic networks. Critically, the adaptive nature of this reconfiguration will be assessed by relating behavioral performance to the degree to which regions integral for task performance are important for communication within that context-specific network.

描述（由申请人提供）：大脑具有惊人的能力，可以根据不断变化的环境的需求灵活地参与不同的功能网络。有时，作用于内在基线环境的力量是短暂的，例如日常生活的动态认知需求。有时它们是长期的，有时是永久性的，例如由于衰老、脑损伤或精神疾病而发生的变化。最近，人们开始关注使用功能磁共振成像 (fMRI) 来测量休息期间大脑区域网络的内在功能连接。将数学领域的图论工具应用于这些内在的大脑网络可以量化网络属性，例如大脑区域组将自身分成很大程度上独立的网络（或模块）的程度，以及识别各个大脑区域的作用，例如某个区域是否是多个大脑区域和网络之间通信的组成部分，或者某个区域是否将其交互限制在单个网络内的一小部分大脑区域。该提案旨在将内在大脑网络的这种表征扩展到其他环境中，以评估大脑在不同环境下的可塑性潜力。因此，拟议的研究将研究全球大脑组织的重新配置以及在两种不同背景下内部网络配置中各个大脑区域的角色变化：1）由于以下原因而导致的功能中断：局灶性脑损伤；2）由于执行认知任务的不同条件而产生的特定认知需求。方法：本研究计划将应用最先进的方法和分析来实现特定目标。第一个实验将分析从局灶性脑损伤患者和年龄匹配的健康对照组收集的数据，以评估脑损伤后网络重新配置的程度。我假设，如果网络中持续脑损伤的完整组织的作用变得更类似于受损组织在健康的内在脑组织中的作用，就会发生适应性网络重新配置。我预测网络内适应是一种更准确地表征大脑组织补偿性变化的方式，而不是纯粹关注解剖上接近受损组织（即病灶周围组织）的完整组织或未受损组织（即病变周围组织）中同源区域的完整组织。，对侧）半球。第二个实验将检查健康年轻人的大脑在不同认知环境中重新配置的能力。我假设自适应网络重新配置将通过将网络组织改变为单个特定于上下文的网络来实现，该网络由认知相关区域和跨独立内在网络的连接组成。至关重要的是，这种重新配置的适应性性质将通过将行为表现与任务表现不可或缺的区域对于特定环境网络内的通信的重要程度相关联来评估。