Language Switching with Alzheimer's Disease

我们提出了一系列研究，应用认知神经心理学的方法来研究 西班牙语-英语双语者阿尔茨海默病(AD)的行为表现。我们使用双语模式 阿尔茨海默病患者的语言处理和认知能力下降激发实验操作，这将揭示 双语阿尔茨海默病患者认知功能障碍的机制/S。我们还解决了关键的实际问题， 旨在确定双语者在认知评估过程中是否应该被允许使用任何一种语言，如果 一种语言的测试会阻碍另一种语言的后续性能，更广泛地说，如何最大化 测试双语者对AD的表现和测试敏感性。理论上的考虑始于证据： 尽管当双语者只说一种语言时，他们似乎与单一语言者没有什么不同，但两者都 语言始终保持活跃状态(它们不能仅仅“关闭一种语言”)。双语者也会转换语言 无论是跨越语境(例如，在家中还是在工作中)，以及在句子中(当与其他双语者交谈时)。 由于只在某些时候使用每种语言，双语者使用每种语言的频率也低于 只会说一种语言的人，他们只使用一种他们知道的语言。因此，双语者面临着独特的控制要求 他们的日常语言使用：选择说哪种语言，转换语言，提取更少的东西 经常使用的语言表示法，以及管理语言之间的竞争。团结在一起， 拟议中的研究将考察这些差异如何影响一些最常用的认知测试 (例如，图片命名、列表记忆、语言流畅性)。这些研究还将检查实验任务。 旨在引出更自然的相关演讲，包括参考沟通任务和阅读- 最近在双语者中表现出对AD敏感的发声任务。每一项拟议的研究都集中在关键 我们假设会影响考试成绩的因素--尤其是患有阿尔茨海默病的双语者--包括：(A) 在测试块之间切换语言(顺序效应)，(B)在测试块内切换( 语言“选项)，以及(C)具有来自语义和句法上下文的不同程度的支持的切换。我们 假设与健康对照组相比，双语AD患者将表现出更大的测试顺序效应，并且 从“使用任何一种语言”的选择中获益减少(这会导致自愿转换语言)。 患有阿尔茨海默病的双语者也可能表现出更明显的转换障碍和施加控制能力降低 当句法上下文不支持语言切换时使用的主要语言。建议进行的研究 将开发诊断双语者阿尔茨海默病的独特工具，并将揭示哪些认知机制 对于在单一认知系统中管理两种语言的激活、表征和使用至关重要。反过来, 拟议的研究将限制双语语言处理的心理语言学模型，并将提供 关于双语能力如何导致老年人认知功能保持更高水平的线索 在AD中，双语能力的哪些方面最具挑战性？

We propose a series of studies that apply a cognitive neuropsychological approach to investigate the behavioral presentation of Alzheimer’s disease (AD) in Spanish-English bilinguals. We use models of bilingual language processing and cognitive decline in AD to motivate experimental manipulations that will reveal the mechanism/s underlying cognitive deficits in bilinguals with AD. We also address critical practical questions, aiming to determine if bilinguals should be allowed to use either language during cognitive assessment, if testing in one language hinders subsequent performance in the other, and more generally how to maximize test performance and test sensitivity to AD in bilinguals. Theoretical considerations begin with evidence that although bilinguals do not seem different from monolinguals when they speak in just one language, both languages always remain active (they cannot just “shut one language off”). Bilinguals also switch languages both across contexts (e.g., at home vs. at work), and within sentences (when conversing with other bilinguals). By virtue of using each language only some of the time, bilinguals also use each language less frequently than monolinguals who only use the one language they know. Thus, bilinguals face unique control requirements in their everyday language use: choosing which language to speak, switching languages, retrieving less frequently used linguistic representations, and managing competition between languages. Together, the proposed studies will examine how these differences affect some of the most commonly used cognitive tests (e.g., picture naming, list memory, verbal fluency). These studies will also examine experimental tasks designed to elicit more naturalistic connected speech, including a referential communication task and a read- aloud task that recently demonstrated sensitivity to AD in bilinguals. Each proposed study focuses on key factors that we hypothesize can affect test performance – especially in bilinguals with AD, including: (a) switching languages across testing blocks (order effects), (b) switching within a testing block (the “either language” option), and (c) switching with varying degrees of support from semantic and syntactic context. We hypothesize that relative to healthy controls, bilinguals with AD will exhibit larger testing order effects, and reduced benefit from the option to “use either language” (which invites voluntary language switching). Bilinguals with AD may also exhibit more prominent switching deficits and reduced ability to exert control over the dominant language when language switches are not supported by syntactic context. The proposed studies will develop unique tools for diagnosis of AD in bilinguals and will reveal which cognitive mechanisms are critical for managing activation, representation, and use of two languages in a single cognitive system. In turn, the proposed studies will constrain psycholinguistic models of bilingual language processing and will provide clues as to how bilingualism leads to higher maintenance of cognitive functioning in older age by revealing which aspects of bilingualism are most challenging in AD.