The Bilingual Effect on Speaking

描述（由申请人提供）：双语者认识的单词几乎是单语者的两倍。他们似乎毫不费力地在正确的上下文中使用正确的单词，甚至可以在语言之间来回切换，几乎没有明显的代价。尽管如此，有证据表明，在单一认知系统中保持一种以上的语言会引入处理差异，并且随着双语者年龄的增长，一些对说话的双语影响会增加。一个明显的（也是流行的）关于双语效应的解释是，知道两个单词来表达任何给定的概念会导致语言之间的竞争。然而，我们认为，语言使用模式的差异本身就足以解释双语对说话的一些影响。我们研究了双语对说话的影响，目的是约束所有说话者的双语和语言产生模型（第1部分）。我们假设，双语者与单语者在某些方面存在差异，这些差异要么与他们不同的语言使用模式有关，要么是因为同样的任务有时会给双语者和单语者带来不同的挑战。我们测试了两种不同的关于双语如何影响单字生成、句子流利程度和语音错误（包括舌尖或TOT状态、整个单词替换和语音错误）的预测。我们还致力于开发双语控制模型，并通过引入一种以前未研究过的语言转换类型和明确操纵双语激活程度来识别可能是双语者独有的处理机制（第2节）。我们考虑的机制对衰老如何影响双语表现做出了不同的预测，我们将这些预测作为开发双语模型和解释认知表现中与年龄相关的变化的手段进行了测试。通过识别双语效应的普遍性，我们确定了年轻和老年双语者在各种任务中的正常表现，并将确定允许不同类型的双语者尽可能流利地发挥作用的条件。这些实验将限制单语和双语语言产生模型，双语和认知控制模型，以及与年龄相关的加工变化的解释，包括加工劣势（例如，与年龄相关的认知控制下降）和加工优势（例如，老年人增加了词汇经验）。

DESCRIPTION (provided by applicant): Bilinguals know virtually twice as many words as monolinguals. They seem to effortlessly use the right word in the right context, and can even switch back and forth between languages with little obvious cost. Nonetheless, evidence suggests that maintaining more than one language in a single cognitive system introduces processing differences, and some bilingual effects on speaking increase as bilinguals age. An obvious (and popular) account of the bilingual effect on speaking is that knowing two words to express any given concept introduces competition between languages. However, we propose that differences in patterns of language use alone are sufficient to explain some of the consequences of bilingualism for speaking. We investigate bilingual effects on speaking with the goal of constraining models of bilingualism and of language production in all speakers (Section I). We hypothesize that bilinguals differ from monolinguals in circumscribed ways that are either related to their different patterns of language use or arise because the same tasks sometimes present bilinguals and monolinguals with different challenges. We test the predictions of two different accounts of how bilingualism should affect single word production, sentence level fluency, and speech errors (including tip-of-the-tongue or TOT states, whole word substitutions, and sound errors). We also aim to develop models of bilingual control and to identify processing mechanisms that may be unique to bilinguals by introducing a previously uninvestigated type of language switching and by explicitly manipulating the degree of dual-language activation (Section II). The mechanisms we consider make different predictions about how aging should affect bilingual performance, and we test these predictions as a means of developing models of bilingualism and accounts of age-related changes in cognitive performance. By identifying the generality of the bilingual effect, we determine what constitutes normal performance for young and aging bilinguals in a variety of tasks, and will identify the conditions that allow bilinguals of different types to function as fluently as they can. The proposed experiments will constrain models of monolingual and bilingual language production, models of bilingual and cognitive control, and accounts of age-related processing changes including both processing disadvantages (e.g., age-related decline in cognitive control) but also processing advantages (e.g., older adults have increased experience with words).