BRAIN AND BEHAVIOR INDEXES OF THE ARITHMETIC ORGANIZATION IN BILINGUALS

描述(由申请人提供)：学习一门以上的语言会改变行为以及大脑的结构和功能组织，这些变化超出了语言的范畴。因此，双语者不能简单地被视为一个大脑中的两个单一语言者，在一个五分之一的人在家里说英语以外的语言的国家，了解双语如何影响其他认知系统是至关重要的。这项提议旨在了解如何为每种语言的多种双语格式、数字和数字词表示和获取算术事实，如乘法表。语言和算术被认为是紧密联系在一起的，因为算术概念是通过言语学习的。因此，懂多种语言可能会影响这些概念的组织和处理方式。我们提出了一系列研究，使用事件相关电位(ERPs)-一种对大脑皮层活动的快速时间动态敏感的技术-以及行为表现分析，以揭示在处理每种格式的算术概念时的定性和定量差异。我们测量了简单乘法问题(3x2=6)的解的响应时间(RT)和事件相关电位(ERPs)，在该问题中，操作数和解之间的同余被操纵。不同格式的一致试验和不一致试验之间的处理差异可以阐明算术事实表征的联系和基本结构。初步数据表明，学习算术的语言(LOLA)，而不是占主导地位的语言(L1)，比另一种语言(LL2)具有更强和更准确的表征。AIM 1通过操纵解决方案在代码之间创建语言切换来测试表示之间的代码间连接。这将使我们能够根据开关的方向确定任何不对称的开关成本，并反过来测试抑制机制。目标2将确定LL2的熟练程度是否可以改进这种格式的算术事实的表示。类似地，Aim 3询问在LL2中专门使用算术事实的经验是否可以改善这个网络中的表示。也就是说，可以通过实践重新学习，比如对于用第二语言教授数学的个人来说，扭转了Lola和LL2之间的强烈不对称。我们将首先测量每个目标的速度、正确性判断和准确性，以发现代码之间任何明显的行为差异。然后我们将测量两个对算术概念之间的算术一致性和关联性敏感的ERP成分，N400，刺激开始后最高400ms的负波，对心理词典中条目之间的激活扩散敏感，以及后期正向成分，反映对意外解决方案的更多受控加工。这些分量的幅度、潜伏期或分布的变化可以阐明码内和码之间的联系。我们的研究将测试目前唯一的双语算术模型，并导致更好地理解算术的大脑组织，以及在正常和异常条件下学习和使用的后果。 公共卫生相关性：研究集中在语言和算术概念之间的联系(例如，Dehaene等人，2003；Campbell等人，1999；Campbell和Epp，2004)，但还没有能够在单一语言系统中明确地显示这些概念之间的关系，也没有阐明在使用一种以上语言的大脑中进行算术处理的独特环境。目前的项目使用脑电活动的直接测量-事件相关电位-以及行为分析来揭示双语者的三个代码(第一和第二语言以及阿拉伯数字)中简单算术的概念表征之间的联系，以及理解每个代码中潜在的认知和神经过程的性质。这些研究将开始阐明双语者语言表现差异的基础，同时提供更广泛的语言和算术模型，最终有助于我们了解儿童学习障碍的处理障碍，如计算障碍，并改进教学和测试方法，同时考虑到双语者和单语者的差异处理策略。

DESCRIPTION (provided by applicant): Learning more than one language alters behavior and the structural and functional organization of the brain, with changes extending beyond the realm of language. Thus the bilingual cannot be viewed as simply two monolinguals in one brain, and in a country where 1 in 5 people speak a language other than English at home, it is essential to understand how being bilingual can impact other cognitive systems. This proposal aims to understand how arithmetic facts, such as multiplication tables, are represented and accessed for the multiple bilingual formats, digits and number words in each language. Language and arithmetic are thought to be tightly linked because arithmetic concepts are learned through verbalization. Thus, knowing more than one language may affect the way in which these concepts are organized and processed. We propose a series of studies that use event related potentials (ERPs) - a technique sensitive to the rapid temporal dynamics of cortical brain activity - along with behavioral assays of performance, to uncover qualitative and quantitative differences in processing arithmetic concepts in each format. We measure response times (RT) and ERPs to the solutions of simple multiplication problems (3x2=6) in which the congruence between operands and solutions is manipulated. Processing differences between congruent and incongruent trials across formats can shed light on the connections and basic structure of arithmetic fact representation. Preliminary data indicate that the language of learning for arithmetic (LolA), rather than the dominant language (L1), has stronger and more precise representations than the other language (LL2). Aim 1 tests the intercode connections between representations by manipulating the solution to create language switches between codes. This will allow us to determine any asymmetrical switching costs based on the direction of a switch and in turn test inhibitory mechanisms. Aim 2 will determine if the level of proficiency in Ll2 can improve the representation of arithmetic facts in this format. In a similar vein, Aim 3 asks whether experience specifically using arithmetic facts in Ll2 can improve the representations in this network. That is, can relearning through practice, such as for individuals teaching math in their second language, reverse the strong asymmetries between LolA and Ll2. We will first measure the speeded correctness judgments and accuracy for each aim, to uncover any overt behavioral differences across the codes. We will then measure 2 ERP components that are sensitive to arithmetic congruency and relatedness between arithmetic concepts, the N400, a negative wave peaking 400 ms post-stimulus onset sensitive to the spread of activation between entries in the mental lexicon, and the Late Positive Component, reflecting more controlled processing of unexpected solutions. Changes in amplitude, latency or distribution of these components can elucidate the connections within and between codes. Our studies will test the only current model for bilingual arithmetic, and lead to a better understanding of the brain organization for arithmetic, with consequences for learning and use under normal and abnormal conditions. PUBLIC HEALTH RELEVANCE: Studies have focused on the connection between language and arithmetic concepts (e.g., Dehaene et al., 2003; Campbell, et al., 1999; Campbell and Epp, 2004), but have not been able to show the relationship between these definitively in a single language system, nor have they elucidated the unique circumstances surrounding arithmetic processing in a brain with more than one language. The current project uses a direct measure of electrical brain activity - event related potentials - along with behavioral assays to uncover the connections between the conceptual representations for simple arithmetic in a bilingual's three codes (first and second languages and Arabic digits), as well as to understand the nature of the underlying cognitive and neural processes within each code. These studies will begin to elucidate the basis of performance differences observed across a bilingual's languages, and at the same time inform models of language and arithmetic more generally, which can ultimately inform our understanding of impaired processing in childhood learning disabilities, such as dyscalculia, as well as to improve teaching and testing methodologies taking into account differential processing strategies for bilinguals and monolinguals alike.