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：
8315847
负责人：
Jessica R Cohen
金额：
$ 5.22万
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. PUBLIC HEALTH RELEVANCE: This research will further knowledge of the adult brain's potential for plasticity due to changes to its intrinsic, baseline environment, including brain damage, aging, and the cognitive demands of a dynamically altering environment. It is proposed that a potential mechanism underlying neural plasticity is the changing role of individual brain regions to adapt to the demands of the current environment and that this plasticity results in reconfiguration that is adaptive (as assessed by network organization close to a healthy state after brain damage and a relationship between reconfiguration and performance in healthy networks during cognitive performance). Crucially, this increased knowledge can lead to treatments involving cognitive training and rehabilitation in cognitively impaired or brain-damaged individuals that target adaptive reconfiguration.

描述（由申请人提供）：大脑具有基于不断变化的环境的需求而灵活参与不同功能网络的惊人能力。有时，作用于内在的基线环境的力是短暂的，例如日常生活的动态认知需求。在其他时候，它们是长期的，偶尔是永久的，例如由于衰老，脑损伤或精神疾病而发生的变化。最近，使用功能性MRI（fMRI）在REST期间衡量大脑区域网络网络的固有功能连通性。从数学领域到这些固有的大脑网络采集的图理论工具的应用可以量化网络属性，例如大脑区域群体在很大程度上将自己分为很大程度上独立的网络（或模块）的程度，以及单个大脑区域的作用，例如在多个大脑区域中的跨多个区域和一个区域之间的互动或一个区域是否相互互动，是否是一个区域的一体范围。该建议旨在将内在的大脑网络的特征扩展到其他情况，以评估大脑在不同情况下的可塑性的潜力。因此，拟议的研究将调查全球大脑组织的重新配置，以及各个大脑区域从固有网络配置在两种不同的情况下的变化局灶性大脑病变，以及2）由于认知任务的不同条件而引起的特定认知需求。方法：本研究建议将采用最新的方法和分析来解决具体目标。第一个实验将分析从患有局灶性脑病变和年龄匹配的健康对照的患者收集的数据，以评估脑损伤后网络重新配置的程度。我假设，如果网络中完整的组织在网络中的作用持续脑损伤变化，以与受损的组织在健康的内在脑组织中的作用更相似，则会发生自适应网络重新配置。我预测，与纯粹关注完整的组织在解剖学上的完整组织相比，网络内的适应性是一种更准确的表征大脑组织中补偿性变化的方式，在未受损的半脑（即，相反）半脑中，在解剖学上的完整组织（即，围环组织）或同源区域的完整组织。第二个实验将检查大脑在治愈年轻人中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更改为由单独的内在网络跨认知相关区域和连接组成的单个上下文特定网络。至关重要的是，将通过将行为绩效与任务绩效组成部分相关的程度来评估这种重新配置的适应性，这对于在该上下文特定的网络中对沟通至关重要。公共卫生相关性：这项研究将进一步了解成年大脑的可塑性，这是由于其内在，基线环境的变化，包括大脑损伤，衰老以及动态改变环境的认知需求。有人提出，神经可塑性的潜在机制是各个大脑区域适应当前环境需求的作用，这种可塑性会导致适应性的重新配置（正如网络组织在脑损伤后接近健康状态的网络组织评估，以及在认知能力表现过程中健康网络中重新配置和在健康网络中的重新配置之间的关系）。至关重要的是，这种增加的知识会导致涉及靶向适应性重新配置的认知受损或脑部损害的个体的认知训练和康复的治疗方法。