Neural correlates of treatment-induced recovery of phonological processing in chronic aphasia

 描述(由申请人提供)：这个项目的总体目标是确定慢性失语症患者治疗后语音恢复的神经相关因素。语音缺陷(语音处理)是左半球中风后失语症中最常见和最持久的损害之一，可能会对口语和书面语言产生重大的功能后果。这些缺陷通常通过行为疗法来治疗，这些行为疗法包括有针对性的活动，鼓励大脑重组，以支持语言技能的重新学习。虽然许多人通过治疗获得了相当大的收益，但支持这些改善的神经底物却鲜为人知。具体地说，当高度专门化的左半球永久语言区域受损时，如何支持语音技能的提高尚不清楚。为了解决这个问题，我建议研究在语音治疗前后功能磁共振成像(FMRI)过程中与语音任务(假词阅读)相关的大脑区域激活的变化。采用病例系列设计，对8名经历了左侧大脑中动脉中风的人进行研究，研究在四次扫描过程中(治疗前两次，治疗后两次)在假词阅读过程中的反应准确性和fMRI激活。假词阅读的行为改善将通过与治疗前、治疗中和治疗后收集的临床数据进行比较来验证。循证治疗方案将作为正在进行的研究项目(授予教师赞助者的R01DC07646-09)的一部分实施，持续约14周。假词阅读任务引起的治疗前后大脑激活的差异将被视为一种治疗效果。假词阅读能力的改善与对语言网络和周边组织未受损(即残留)的左侧永久区域的依赖有关。也有人预测，成功的治疗反应将需要更多的注意力资源来支持任务表现，这应该通过增加背部的双半球额顶网络的激活来证明。这项研究的发现有望更好地理解支持语言恢复的神经机制，并有可能为失语症的治疗方法提供参考。1

 DESCRIPTION (provided by applicant): The overall goal of this project is to identify the neural correlates of treatment-induced recovery of phonology in individuals with chronic aphasia. Deficits in phonology (speech sound processing) are among the most common and persistent impairments in aphasia after left hemisphere stroke, and can have significant functional consequences for spoken and written language. These deficits are typically treated with behavioral therapy involving targeted activities that encourage brain reorganization to support relearning of language skills. While many individuals make considerable gains through treatment, the neural substrates supporting these improvements are poorly understood. Specifically, it is not clear how improved phonological skills are supported when highly specialized left-hemisphere persiylvian language regions are damaged. To address this question, I propose to study changes in regional brain activation associated with a phonological task (pseudoword reading) performed during functional magnetic resonance imaging (fMRI) before and after phonological treatment. Using a case series design across eight individuals who experienced left middle cerebral artery stroke, I will study response accuracy and fMRI activation during pseudoword reading over the course of four scanning sessions (2 before and 2 after treatment). Behavioral improvement in pseudoword reading will be validated by comparison with clinical data collected before, during, and after treatment. The evidence-based treatment protocol will be implemented as part of an ongoing research project (R01DC07646- 09 awarded to the faculty sponsor), lasting approximately fourteen weeks. Differences in pre-post treatment brain activation evoked by the pseudoword reading task will be considered an effect of therapy. It is hypothesized that improvements in pseudoword reading will be associated with reliance on the undamaged (i.e. residual) left persiylvian regions of the language network and perilesional tissue. It is also predicted that a successful treatment response will require increased engagement of attentional resources to support task performance, and this should be evident by increased activation of a bi-hemispheric fronto-parietal network dorsal to the perisylvian language region. The findings from this study are expected to provide a better understanding of the neural mechanisms that support language recovery, and have the potential to inform treatment approaches for aphasia. 1