UNDERSTANDING THE EFFECTS OF STROKE USING FUNCTIONAL CONNECTIVITY MRI

摘要（官方） 描述（由申请人提供）：行为缺陷和中风造成的解剖损伤之间的关系只是部分的，因为生理功能障碍可以在远离病变的脑区测量。这些非局部生理缺陷可以使用功能连接磁共振成像（fcMRl）来评估，其测量血氧水平依赖（BOLD）信号中脑区域之间的时间相关性。在健康成年人中的fcMRl研究已经确定了作为不同行为功能（如注意力、运动控制和语言）基础的分布式脑网络。我们先前对具有空间忽视的中风患者的工作已经表明，注意力网络内的fcMRl缺陷与患者在被忽视领域中的缺陷相关。这项资助提出，fcMRl可以更广泛地用于理解中风在行为领域产生的缺陷。我们将在中风患者的大样本中测量fcMRl，并测试中风如何在脑网络中产生功能障碍以及这种功能障碍如何与行为缺陷相关的几种假设。我们预测，减少在运动和注意力网络，这是双边组织的半球间连接，将与相应的行为缺陷，这些相关性将显示功能特异性。例如，手臂定义的运动网络内的连接性将比下肢功能更好地预测上肢功能。我们确定连接和行为之间的相关性，在一个不对称的组织网络，语言，并比较半球间与半球内连接的重要性。我们研究了多个大脑网络的功能如何相互作用，产生一个单一的行为缺陷，并假设一些网络的连接，如注意力，与跨域的行为相关。我们纵向测量fcMRl以确定连接性是否以不同速率在不同网络中恢复以及该恢复是否与行为恢复相关。最后，我们研究了中风所产生的连通性变化如何取决于结构受损的神经束类型。

Abstract (Official) DESCRIPTION (provided by applicant): The relationship between the behavioral deficits and anatomical damage produced by a stroke is only partial, since physiological dsyfunction can be measured in brain regions far removed from the lesion. These non-local physiological deficits can be assessed using functional connectivity magnetic resonance imaging (fcMRl), which measures the temporal correlation between brain regions in the blood-oxygenation-level-dependent (BOLD) signal. Studies of fcMRl in healthy adults have identified distributed brain networks that underlie different behavioral functions, such as attention, motor control, and language. Our previous work on stroke patients with spatial neglect has shown that fcMRl deficits within the attention network correlate with a patient's deficit in the neglected field. This grant proposes that fcMRl can be used more broadly to understand the deficits produced by stroke across behavioral domains. We will measure fcMRl in a large, heterogeneous sample of stroke patients, and test several hypotheses of how strokes produce dysfunction in brain networks and how this dysfunction correlates with behavioral deficits. We predict that decreases in inter-hemispheric connectivity in motor and attention networks, which are bilaterally organized, will correlate with corresponding behavioral deficits and that these correlations will show functional specificity. For example, connectivity within an arm-defined motor network will predict upper-extremity function better than lower-extremity function. We determine the correlation between connectivity and behavior in an asymmetrically organized network, language, and compare the importance of inter-hemispheric vs intra-hemispheric connectivity. We examine how the functioning of multiple brain networks interact to produce a single behavioral deficit, and hypothesize that the connectivity of some networks, such as attention, correlates with behavior across domains. We measure fcMRl longtitudinally to determine if connectivity recovers in different networks at different rates and whether that recovery correlates with behavioral recovery. Finally, we study how changes in connectivity produced by a stroke depend on the type of tracts that are structurally damaged.