Bilingualism as a cognitive reserve factor: the behavioral and neural underpinnings of cognitive control in bilingual patients with aphasia

项目总结/摘要 在双语领域，最近有一个转向调查终身行为是如何影响双语能力的。 掌握两种语言可能会使双语者在衰老1和面对临床神经病理学时受益。 4这种研究的动机是管理两种或两种以上的语言需要参与的想法。 各种控制过程5，6潜在地导致更有效地执行领域通用认知控制， 这反过来又有助于更大的认知储备。确定影响行为的因素 双语者在临床神经病理学方面的优势 需要仔细考虑被检查的结构以及潜在的神经激活 与行为表现有关。此外，在检查执行功能时， 特别是围绕着结果的生态有效性。使用允许完成的成像模式 自然环境中的任务（例如，功能近红外光谱（fNIRS）， 脑电图（EEG））而不是仰卧在扫描仪中（例如，功能磁共振 功能磁共振成像（fMRI））增加了结果的生态有效性，并允许更强大的解释， 结果的普遍性7 因此，本研究的目标是检查行为（准确性和反应时间的措施）和 两名患者（单语（MPWA）和双语（BPWA）患者）的神经（fNIRS和EEG）反应 失语症）和两个健康对照组（双语（BHC）和单语（MHC））的认知控制 任务，以消除执行功能的哪些组成部分（例如，转移、抑制和/或更新）8，9 受到双语能力的影响，以及这如何转化为失语症的认知储备因素。目标1： 研究了在三个非语言认知控制任务上的行为表现的群体差异， 双语和单语患者和健康对照组。目标2：检查 双语者和非语言认知控制任务期间的fNIRS血流动力学反应功能（HRF） 患者和健康对照组的单语者。目的3：检查EEG频率的组间差异 双语者和单语者在非言语认知控制任务中的频带功率 健康对照组。本研究的结果将为双语对行为的影响提供证据 和神经表现，并阐明如何双语作为一个认知储备因素失语症。的 这项研究的设计可以作为一个框架，为生态有效的调查的行为和 双语者和单语者在认知任务上的神经动力学表现 临床人群。

PROJECT SUMMARY/ABSTRACT In the field of bilingualism there has been a recent shift towards investigating how the lifelong act of managing two languages may benefit bilingual individuals in aging1 and in the face of clinical neuropathology.2- 4 This vein of research is motivated by the idea that managing two or more languages requires engagement of various control processes5,6 potentially leading to more efficient execution of domain-general cognitive control, which in turn contributes to greater cognitive reserve. Determining the factors that contribute to a behavioral advantage for bilinguals as compared to monolinguals in the face of comparable clinical neuropathology requires careful consideration of the constructs being examined as well as the underlying neural activation associated with behavioral performance. Furthermore, a critical concern when examining executive functioning in particular surrounds the ecological validity of results. Using imaging modalities that allow for completing tasks in naturalistic environments (e.g., functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG)) as opposed to laying supine in a scanner (e.g., functional magnetic resonance imaging (fMRI)) increases the ecological validity of results and allows for more robust interpretation and generalizability of results.7 Therefore, the goal of this study is to examine behavioral (accuracy and reaction time measures) and neural (fNIRS and EEG) responses across two patient (monolingual (MPWA) and bilingual (BPWA) patients with aphasia) and two healthy control (bilingual (BHC) and monolingual (MHC)) groups on cognitive control tasks, to disambiguate which components of executive functioning (e.g., shifting, inhibiting, and/or updating)8,9 are impacted by bilingualism and how this may translate to a cognitive reserve factor in aphasia. Aim 1: examines group differences in behavioral performance on three non-verbal cognitive control tasks between bilinguals and monolinguals across patient and healthy control groups. Aim 2: examines group differences in fNIRS hemodynamic response function (HRF) during non-verbal cognitive control tasks between bilinguals and monolinguals across patient and healthy control groups. Aim 3: examines group differences in EEG frequency band power during non-verbal cognitive control tasks between bilinguals and monolinguals across patient and healthy control groups. Results of this study will provide evidence of the impact of bilingualism on behavioral and neural performance and elucidate how bilingualism serves as a cognitive reserve factor in aphasia. The design of this study can be used as a framework for an ecologically valid investigation of the behavioral and neural dynamics underlying performance on cognitive tasks across bilinguals and monolinguals in neurotypical and clinical populations.