Neural and behavioral investigations of dissociations in conceptual and linguistic factors influencing verb retrieval in people with aphasia

项目摘要 在美国，大约三分之一的中风幸存者患有失语症，这是一种影响 使用和/或理解语言的能力。单词提取障碍是失语症的主要症状。 名词提取缺陷的研究由来已久，但动词受到的关注要少得多。尽管如此， 大约70%的失语症患者有动词提取缺陷，这对失语症的成功具有很高的预测性 日常交流。针对动词提取的行为治疗改善语言功能 和沟通有效性，但对此类治疗反应的潜在机制和预测因素 是不被理解的。这项拟议的研究旨在通过研究行为、神经解剖学、 和提示型变量，这些变量表征了动词提取障碍并促进了成功的动词提取 失语症患者。 这项研究的第一个目标是表征神经解剖学的差异，以预测 失语症患者提取的是语言(动词)信息而不是概念(动作)信息。 在动词和(基于图片的)动作刺激的有效行为组合上的表现将与 白质和灰质的神经解剖学变量。这一比较将测试竞争型号的 语言和概念表征的神经基础，以及失语症语言缺陷。经典认知- 语言学研究假设失语症患者在语言任务中表现不佳，但不是 概念性任务。他们进一步预测，语言障碍的严重程度将与损伤相关 仅限于与语言相关的大脑网络。相比之下，扎根的认知账户预测人们 失语症患者在语言和概念任务上都会有障碍，假设这是由于 损害与语言或动作相关的大脑网络，这些网络共同支持这类任务的表现。 第二个目标是调查有失语症和没有失语症的人是否依赖于语言和语言 动词检索过程中的概念信息。人们会检索动词，以回应语言上的-或 与概念相关的线索。一项启动的动词命名实验将测试这两种信息类型是如何驱动 优先进行语言处理的任务中的动词提取性能(说出你在 屏幕“)。根据先前的发现，假设健康的参与者将表现出更大的促进作用 在这样的命名任务中，与语言相关的线索比与概念有关的线索更重要。失语症患者 在动词命名任务中，如果概念线索被成功地适应，预计会显示出更大的易化性 他们的语言障碍。随后的分析将确定人的水平特征(神经解剖学， 行为)，预测哪些线索有助于失语症患者的动词提取，在群体和 个人层面。这项研究将提供证据，可以促进神经认知模型，为临床提供信息 决策，并指导动词检索干预措施的选择。

Project Summary Approximately one-third of stroke survivors in the United States suffer from aphasia, a disorder that affects the ability to use and/or understand language. Word-retrieval impairments are a cardinal symptom of aphasia. Noun-retrieval deficits have long been studied, but verbs have received much less attention. Despite this, approximately 70% of people with aphasia have verb-retrieval deficits, which are highly predictive of success in everyday communication. Behavioral treatments targeting verb retrieval result in improved language function and communicative effectiveness, but the underlying mechanisms and predictors of response to such treatments are not understood. The proposed study aims to addresses this gap by investigating behavioral, neuroanatomical, and cue-type variables that characterize verb-retrieval impairments and promote successful verb retrieval in people with aphasia. The first objective of this research is to characterize neuroanatomical differences that predict how well individuals with aphasia retrieve linguistic (verb) information versus conceptual (action) information. Performance on a validated behavioral battery of verb and (picture-based) action stimuli will be compared to both white-matter and gray-matter neuroanatomical variables. This comparison will test competing models of the neural basis of language and conceptual representations, and of aphasic language deficits. Classic cognitive- linguistic accounts hypothesize that people with aphasia will perform poorly on linguistic tasks, but not conceptual tasks. They further predict that severity of linguistic impairments will be associated with lesions exclusively to language-related brain networks. In contrast, grounded cognition accounts predict that people with aphasia will have impairments in both linguistic and conceptual tasks, hypothesizing that this occurs due to damage in language- or action-related brain networks, which jointly support performance in such tasks. The second objective is to investigate whether people with and without aphasia rely on linguistic versus conceptual information during verb retrieval. People will retrieve verbs in response to either linguistically- or conceptually-related cues. A primed verb-naming experiment will test how these two information types drive verb-retrieval performance in a task that prioritizes linguistic processing (“Name the word you see on the screen”). Based on previous findings, it is hypothesized that healthy participants will show greater facilitation for linguistically-related cues than for conceptually-related cues in such naming tasks. People with aphasia are expected to show greater facilitation for conceptual cues in the verb-naming task if they have successfully adapted to their language impairments. Subsequent analyses will identify person-level traits (neuroanatomical, behavioral) that predict which cues facilitate verb retrieval in people with aphasia, at both the group and the individual level. This research will provide evidence that can advance neurocognitive models, inform clinical decision-making, and guide selection of verb-retrieval interventions.