Lexical retrieval deficits across semantic contexts in stroke-induced aphasia

中风引起的失语症跨语义上下文的词汇检索缺陷

• 批准号: 10537244
• 负责人: Elizabeth Jane Anderson
• 金额: $ 3.65万
• 依托单位: SAN DIEGO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10537244
• 关键词: Affect; Aphasia; Behavior; Behavioral; Behavioral Paradigm; Brain; Brain region; Canis familiaris; Categories; Clinical Assessment Tool; Communication; Dissociation; Electrophysiology (science); Frequencies; Future; Goals; Image; Impairment; Individual; Intervention; Knowledge; Language; Lead; Left; Lesion; Link; Location; Measures; Modeling; Names; Nature; Outcome; Patients; Performance; Play; Prefrontal Cortex; Process; Production; Research; Research Project Grants; Resolution; Retrieval; Role; Semantics; Source; Specificity; Speech; Stroke; Taxonomy; Techniques; Temporal Lobe; Testing; Wolves; clinical development; design; driving force; individualized medicine; innovation; lexical; lexical retrieval; personalized medicine; stroke-induced aphasia; treatment choice; treatment planning

Project Summary The goal of this proposal is to investigate the sources of variability in lexical retrieval deficits in individuals with left hemisphere stroke-induced lesions and how these deficits may be uniquely impacted depending on semantic context. We will achieve this by examining the brain dynamics of lexical retrieval and behavior in individuals with left prefrontal cortex (LPFC) versus left posterior temporal cortex (pLTC) lesions compared to matched controls. Lexical retrieval deficits are observed to some extent in all individuals with stroke-induced aphasia. Lexical activation and selection are key processes enabling us to retrieve words as we speak. Lexical activation occurs through spreading activation from semantic to lexical representations and is facilitated in semantically-related contexts. Lexical selection is the selection of the target word from activated semantically- related alternatives and can be slowed in semantically-related contexts. Lexical retrieval stages can be differently affected depending on the type of semantic context. Taxonomically-related words (e.g., wolf and dog) have been linked with semantic interference. However, thematically-related words (e.g., dog and leash) have been linked with facilitation. Lexical retrieval is often impaired in individuals with aphasia, but the driving forces behind lexical retrieval deficits and how these may be differentially impacted depending on the type of semantic context are not well understood. Separating individuals who have a greater activation versus selection deficit from individuals who have a greater selection versus activation deficit may be a more informative way to characterize lexical retrieval deficits and may help predict the impact of different semantic contexts in a more individualized manner. Here, we propose that activation deficits, corresponding to a deficit in lexical activation, are associated with pLTC lesions as individuals with lesions in the pLTC have been shown to struggle with recognizing the correct word even when presented to them as an option to choose from. Contrastively, we propose that selection deficits, involving a deficit in the ability to suppress co-activated lexical items during selection, are associated with LPFC lesions as the LPFC has been proposed to play a role in overcoming semantic interference. Aim 1 will dissociate individuals with lexical activation versus selection retrieval deficits by using pre-established behavioral paradigms allowing this dissociation. Aim 2 will investigate the impact of taxonomic and thematic relationships on lexical retrieval subprocesses in individuals with pLTC and LPFC lesions through the use of electrophysiological techniques. The results of this study will provide a key step towards understanding how different lexical retrieval deficits interact with semantic contexts, and the associated brain dynamics in stroke-induced aphasia, providing a knowledge basis for the future development of clinical assessment tools for lexical retrieval.

项目摘要 该提案的目的是调查患有词汇检索缺陷的可变性来源 左半球中风引起的病变以及这些缺陷如何受到唯一影响 语义上下文。我们将通过检查词汇检索和行为的大脑动态来实现这一目标 左前额叶皮层（LPFC）与左后颞皮层（PLTC）病变的个体相比 匹配的控件。在所有中风诱导的个体中，都观察到词汇检索缺陷 失语症。词汇激活和选择是关键过程，使我们能够在说话时检索单词。词汇 激活是通过从语义到词汇表示的传播激活而发生的，并在 与语义相关的上下文。词汇选择是从激活的语义上选择目标词的选择 相关的替代方案，可以在语义相关的上下文中放慢速度。词汇检索阶段可以是 根据语义上下文的类型受到不同影响。与分类学相关的单词（例如狼和狗） 与语义干扰有关。但是，主题相关的单词（例如，狗和皮带）具有 与便利有关。失语症的个体经常会损害词汇检索，但是驱动力 在词汇检索缺陷的背后以及如何根据语义的类型对它们产生差异影响 上下文不太了解。分离具有更大激活与选择缺陷的个人 从选择更大与激活赤字的个人可能是一种更有信息的方式 表征词汇检索缺陷，可能有助于预测不同语义环境的影响 个性化的方式。在这里，我们提出激活缺陷，对应于词汇激活的不足， 与PLTC病变有关，因为PLTC中有病变的个体已被证明与 即使将其呈现给它们作为选择的选项，也可以识别正确的单词。相反，我们 提出选择缺陷，涉及抑制共同激活词汇项目的能力的赤字 选择，与LPFC病变相关 语义干扰。 AIM 1将使个人与词汇激活与选择检索缺陷分离 通过使用预先建立的行为范式允许这种解离。 AIM 2将调查 PLTC和LPFC个体中词汇检索子过程的分类和主题关系 通过使用电生理技术的病变。这项研究的结果将提供关键步骤 要了解不同的词汇检索缺陷如何与语义上下文相互作用以及相关的 中风引起的失语症中的大脑动力学，为未来临床发展提供了知识基础 词汇检索的评估工具。