Bilingual Language Control

在日常生活中经常使用一种以上语言的人，即双语者，似乎很容易在语言之间来回切换，没有任何明显的困难。然而，最近的研究表明，双语者和单语者在各种测试中存在微妙但可靠的差异，包括测量语言能力的测试和测量其他认知技能（例如，避免分心的能力）的测试。这种差异在进行测试的所有环境中，包括教育和医疗环境中，都具有潜在的重大影响。在某些情况下，双语者可能比单语者表现得更不流利，因为他们知道其中一种语言中的一些单词，而不知道另一种语言中的一些单词。似乎允许双语者在测试期间在语言之间来回切换应该消除与双语相关的任何测试劣势。然而，在某些测试情况下，语言转换本身也会带来缺点（例如，反应速度变慢）。重要的是要确定人们如何受到他们不同的语言经历的影响，这既是出于与学术目标相关的实际原因，也是出于与发展对人类获得和保持语言技能的能力的理解相关的科学原因。这些知识将影响越来越多的美国人，因为目前超过五分之一的美国人在家说英语以外的语言，而且这个数字还在增长。这些研究将通过一系列的行为实验来比较年轻和年老的西班牙语-英语双语者，旨在确定：1)双语和衰老如何共同影响测试成绩；2)语言转换何时可以提高快速流利地生成单词和句子的能力。当前工作的一个驱动假设是，语言选择有时是相对自动实现的，但在其他时候需要努力。这一假设将通过询问语言转换能力如何随着双语者年龄的增长而变化来验证；尽管自动过程在衰老过程中应该保持不变，但需要集中精力的过程应该减少。这些研究将阐明双语能力和考试成绩之间的关系，并将明确一个清晰的双语语言产生的理论模型，这可能为在教育和医疗环境中为双语个体开发理论驱动的经验优化奠定必要的基础。

People who regularly use more than one language in their daily life, bilinguals, seem to easily switch back and forth between languages without any obvious difficulty. However, recent research studies demonstrated subtle but reliable differences between bilinguals and monolinguals on a variety of tests including both tests that measure linguistic ability and tests that measure other cognitive skills (e.g., the ability to avoid distraction). Such differences have potentially significant implications in all settings where testing occurs, including educational and medical settings. In some cases, bilinguals might appear to be less fluent than monolinguals because they know some words in one of their languages but not in the other. It might seem that allowing bilinguals to switch back and forth between languages during testing should eliminate any testing disadvantage associated with bilingualism. However, language switching can itself introduce disadvantages in some testing situations (e.g., slowing of responses). It is important to identify how people might be affected by their diverse linguistic experiences both for practical reasons related to academic goals and for scientific reasons related to developing an understanding of the human capacity for acquiring and maintaining language skills. Such knowledge will affect an increasing number of Americans as more than 1 in 5 currently speaks a language other than English at home and this number is growing. The proposed studies will compare young to aging Spanish-English bilinguals in a series of behavioral experiments designed to identify 1) how bilingualism and aging jointly affect test performance, and 2) when language switching may enhance the ability to rapidly and fluently produce words and sentences. A driving hypothesis underlying the current work is that language selection is sometimes implemented relatively automatically but at other times requires effort. This hypothesis will be tested by asking how language switching ability changes as bilinguals get older; whereas automatic processes should stay the same in aging, processes that require focused effort should decline. These studies will clarify the relationship between bilingualism and test performance and will specify a well-articulated theoretical model of bilingual language production that may lay the groundwork necessary to develop theory-driven optimization of experience for bilingual individuals in educational and medical settings.