Application of graph theory to both resting-state and task-based fMRI data to uncover brain-behavior relationships related to therapy outcomes in aphasia

项目摘要 虽然存在许多失语症康复的治疗范例，并在行为上取得了成功 结果，关于恢复期间神经重组的“最佳”模式，仍有很多争论。这 缺乏共识的部分原因可能是对神经重组和神经重建之间联系的探索不彻底。 行为。拟议的项目将把图论方法应用于基于任务的和静态的两种状态 功能磁共振成像(rs-fMRI)数据，用于检查与治疗结果相关的功能连接性的变化 患有失语症。图论和rS-fMRI目前在临床行为学中的应用还很少。图论是 在认知科学的其他领域广受欢迎，作为一种有意义的表征技术 大脑网络动力学。静息状态功能磁共振成像在临床研究的其他领域越来越受欢迎，如 对一般认知功能的一种容易获得且信息丰富的测量方法。 20名失语症(PWA)参与者将在四个时间点使用fMRI进行扫描。在扫描1之间 和扫描2，将不提供任何治疗，为每个PWA建立基线对照。在扫描2和 扫描3，将提供为期10周的单词查找治疗。在扫描3和扫描4之间，将不会有任何治疗 以允许测量维护效果。使用的处理方法是抽象词检索 训练。之所以选择这种疗法，是因为它不仅被证明在改善抽动障碍方面是成功的 单词检索，但也改进了对未经训练的相关具体单词的检索(即泛化) (Kiran，Sandberg，&Abbott，2009；Sandberg&Kiran，2014)。这使得治疗更有效，而且 是促进积极神经变化的好人选。此外，抽象和具体的词语也被 显示出不同的神经激活模式。这允许对直接培训进行系统检查 以及治疗对脑重组的概括作用。对于图论分析，区域 兴趣(ROI)将使用数据驱动的空间受限方法来定义，该方法由Hillary博士和 莫勒纳尔。一旦为每个时间点定义了相关矩阵，图论度量将是 在每个时间点进行计算和比较，以系统地检查功能连接性的变化 与治疗结果有关。 本提案中的方法学方法是创新的，使用了之前的两次基线扫描 治疗和治疗后的两次维护扫描以及图论和rS-fMRI在脑血管疾病中的应用 检查失语症患者与治疗相关的脑重组。这一项目的圆满完成是 希望有助于为目前中风后最佳重组模式的理论提供信息，并提供基础 为测量失语症患者的脑重组建立信息量大且合适的方法。

Project Summary Although many treatment paradigms exist for aphasia rehabilitation with behaviorally successful outcomes, there is still much debate regarding the “best” pattern of neural reorganization during recovery. This lack of consensus may be due, in part, to incomplete exploration of the link between neural reorganization and behavior. The proposed project will apply graph theoretical measures to both task-based and resting-state fMRI (rs-fMRI) data to examine changes in functional connectivity related to treatment outcomes in persons with aphasia. Graph theory and rs-fMRI are currently underutilized in clinical aphasiology. Graph theory is gaining popularity in other areas of cognitive science as a meaningful technique for the characterization of brain network dynamics. Resting-state fMRI has been gaining popularity in other areas of clinical research as an easily acquired and informative measure of general cognitive functioning. Twenty participants with aphasia (PWA) will be scanned using fMRI at four time points. Between scan 1 and scan 2, no therapy will be provided, establishing a baseline control for each PWA. Between scan 2 and scan 3, ten weeks of word finding therapy will be provided. Between scan 3 and scan 4, no therapy will be provided, allowing for measurement of maintenance effects. The treatment used is abstract word retrieval training. This treatment was chosen because it has been shown to be not only successful at improving abstract word retrieval, but also improving retrieval of related concrete words that are not trained (i.e., generalization) (Kiran, Sandberg, & Abbott, 2009; Sandberg & Kiran, 2014). This makes the treatment more effective and a good candidate for promoting positive neural changes. Furthermore, abstract and concrete words have been shown to have differing neural activation patterns. This allows for the systematic examination of direct training and generalization effects of treatment on brain reorganization. For the graph theory analysis, regions of interest (ROIs) will be defined using a data-driven spatially-constrained approach developed by Drs. Hillary and Molenaar. Once correlations matrices are defined for each time point, graph theoretical measures will be calculated and compared at each time point to systematically examine changes in functional connectivity related to therapy outcomes. The methodological approach in this proposal is innovative in the use of two baseline scans before treatment and two maintenance scans after treatment and the application of graph theory and rs-fMRI to examine treatment-related brain reorganization in aphasia. The successful completion of this project is expected to help inform current theories of optimal reorganization patterns after stroke and provide groundwork for establishing informative and appropriate methods for measuring brain reorganization in aphasia.