Attention and executive control during lexical processing in aphasia

描述（由申请人提供）：该项目的目的是提高我们对失语症患者（PWA）所经历的认知沟通缺陷的理解。有越来越多的研究记录了PWA的注意力和执行控制障碍，但很少有工作来描述这些障碍与特定语言过程的关系。为了解决这个问题，拟议的项目将实验研究执行注意力（Kane and Engle, 2004）与语言依赖任务中特定的语言和控制过程之间的关系。我们假设至少在一些PWA中存在执行注意力障碍，并且这种障碍的程度应该会影响个人处理语言的能力。该项目将进行两个实验，以检查执行功能和注意力对PWA识别单词和处理其含义的能力的影响。第一个实验将描述PWA在单词识别过程中强调准确性或速度的能力，第二个实验将检查设置（“上传”）执行词汇任务所需的过程的能力。该项目还将描述PWA的执行功能和注意力，并研究它们与语言表现控制的关系。这两个实验将使用词汇决策任务，在这个任务中，参与者指出刺激是真实的单词还是虚构的单词，执行功能和注意力的表征将使用一系列专门的任务来测量这些能力在语言和非语言领域的特定方面。我们将测试20名PWA和20名年龄匹配的对照组。结果将使用词汇决策任务的数学模型来解释，该模型已广泛应用于正常人的研究（扩散模型：Ratcliff， 1978）。我们预测PWA和控制的性能将在特定的扩散模型参数上有所不同，这些参数将与它们如何处理语言和响应不同的任务约束有关。我们还预测PWA在执行和注意力任务中的表现比对照组差，在语言方面的表现比非语言方面的表现下降得更大，这些差异将预测PWA在词汇决策任务中的表现。该项目与健康相关，因为它将使用严格且经过充分验证的建模方法揭示PWA中执行和注意力功能与语言处理之间的关系。预计这将对这些个体的治疗产生重要影响。该项目将成为一个培训计划的一部分，该计划将包括计算建模和统计课程，以及失语症、词汇处理、执行控制和扩散建模领域专家的指导和直接培训。该项目所要求的培训将帮助申请人成为一名能够在实验心理学和失语学之间产生转化研究的独立研究者。

DESCRIPTION (provided by applicant): The goal of this project is to improve our understanding of the cognitive-communication deficits experienced by persons with aphasia (PWA). There is a growing body of research documenting attention and executive control impairments in PWA, but less work has been done to characterize the way in which these impairments relate to specific linguistic processes. To address this, the proposed project will experimentally investigate the relationship between executive attention (Kane and Engle, 2004) and specific linguistic and control processes during language-dependent tasks. We hypothesize that executive attention impairments exist in at least some PWA, and that the degree of this impairment should affect an individual's ability to process language. The project will conduct two experiments that will examine the effect of executive function and attention on PWA's ability to recognize words and process their meanings. The first experiment will characterize the ability of PWA to place emphasis on accuracy or speed during word recognition, and the second will examine the ability to set up ("upload") the processes needed to perform a lexical task. The project will also characterize executive function and attention in PWA and examine their relationship to control of linguistic performance. The two experiments will use the lexical decision task, in which participants indicate whether stimuli are real words or made-up words, and the characterization of executive function and attention will use a battery of specialized tasks designed to measure specific aspects of these abilities in linguistic and nonlinguistic domains. We will test 20 PWA and 20 age-matched controls. Results will be interpreted using a mathematical model of the lexical decision task that has been widely applied in studies of normal individuals (diffusion modeling: Ratcliff, 1978). We predict that PWA and control's performance will differ on specific diffusion model parameters that will be related to how they process language and respond to different task constraints. We also predict that PWA will demonstrate worse performance than controls in the executive and attention tasks, with a greater decrement in performance in linguistic compared to nonlinguistic measures, and that these differences will be predictive of PWA performance on the lexical decision tasks. The project is relevant to health because it will reveal relationships between executive and attention functions and linguistic processing in PWA, using a rigorous and well-validated modeling approach. This is expected to have important implications for treatment of these individuals. This project will be part of a training program that will involve coursework in computational modeling and statistics, as well as mentorship and direct training from experts in the areas of aphasia, lexical processing, executive control, and diffusion modeling. The training entailed by this project will help prepare the applicant to become an independent investigator capable of generating translational research between experimental psychology and aphasiology.