The Role of Language Similarity in the Development of the Infant Bilingual Lexicon

在双语家庭中长大的婴儿是如何学习单词的，这些单词在婴儿的双语头脑中是如何表现的？我们建议，这些问题的答案在很大程度上受到所涉及的语言的相似性。例如，荷兰语和英语是近距离的语言，而汉语和英语是远距离的。在词汇层面上，语言相似性反映在两种语言共有的“同源”词汇的百分比上。同源词是具有相同词源和发音相似的词的翻译（例如英语和荷兰语中的父亲和维德）。同源词在双语者中的重要性的证据来自于对成年人的命名研究。例如，成年双语者能更快地命名与同源词（父亲/维达）相对应的图片，而不是与非同源词（自行车/fiets）相对应的图片。成人双语能力的一个重要特征是对两种语言中的单词的非选择性获取。双语者激活所有潜在的候选词从任何一种语言与他们听到或想说的一致，即使在完全单语的情况下。这些发现指出了双语者大脑中两种语言之间重要的相互作用。这种相互作用在双语养育的婴儿中可能更为重要。这些婴儿通常只知道他们语言中的一个词来指代一个概念。在这种情况下，跨语言的词汇相似性可能有助于词汇识别，但它可能会阻碍特定语言词汇的建立。我们建议进行一系列的实验研究，以揭示双语婴儿的心理词汇的结构，并构建脑启发模型，探索其词汇结构的理论解释（S）。我们将利用牛津和巴塞罗那的双语学习环境。在巴塞罗那，有现成的双语婴儿学习西班牙语和加泰罗尼亚语（两种罗曼语共享许多同源词）。在牛津，有足够多的双语西班牙语和英语家庭。西班牙语和英语的同源词较少，与Barcelona contexts.Experiments形成了鲜明的对比：我们将使用新的实验范式，该范式在牛津婴儿实验室（Oxford BabyLab）的单语婴儿中率先使用，采用了众所周知的眼动追踪和神经成像技术。用单语婴儿开发的方法非常适合探索我们的研究问题。这些任务涉及婴儿在听语音的同时看图片。通过监测他们的眼球运动和记录他们的大脑活动，我们希望发现他们的两种语言如何影响他们对所看到的图片的反应的重要线索。该项目在方法上的一个重要优势是，它将以纵向方式跟踪婴儿的表现-18、24和30个月。纵向设计使我们能够考虑到婴儿在词汇发展方面的显著个体差异，并对项目收集的数据进行复杂而强大的统计分析。我们还将测试单语婴儿完全相同的一套研究作为我们的双语人口，从而提供了适当的基线，以评估双语婴儿。建模：在构建神经模型的目的是了解的机制，观察到的行为。目前的双语计算模型只考虑成年人（大而稳定）的词汇。我们将开发第一个早期双语学习的计算模型。最近，我们已经展示了单词学习神经网络模型中自组织过程的发展变化如何捕捉婴儿行为的重要方面。我们将把这些建模的见解从单语婴儿单词学习和识别到婴儿双语发展，以一种尊重我们实验结果的方式。

How do infants growing up in bilingual homes learn words and how are these words represented in the infant bilingual mind? We propose that answers to these questions are heavily influenced by the similarity of the languages involved. For instance, Dutch and English are close languages, while Chinese and English are distant. At the word level, language similarity is reflected in the percentage of 'cognate' words that two languages share. Cognates are word translations that share the same etymological origin and sound similar (such as father and vader in English and Dutch). Evidence for the importance of cognates in bilinguals comes from naming studies with adults. For example, adult bilinguals can name pictures faster when they correspond to cognates (father/vader) than pictures corresponding to non-cognates (bicycle/fiets). A critical property of adult bilingualism is that of non-selective access to the words in both languages. Bilinguals activate all potential word candidates from either language consistent with what they hear or want to say, even in fully monolingual situations. Such findings point to important interactions between the two languages in the bilingual mind. Such interactions are likely to be even more important in the case of infants raised bilingually. Such infants often know only one word in one of their languages to refer to a concept. In this situation, cross-language lexical similarity may facilitate word recognition, but it may hinder the establishment of language-specific lexicons. We propose to conduct a series of experimental studies to uncover the structure of the mental lexicon in bilingual infants, and to construct brain-inspired models to explore theoretical accounts of the structure of their lexicon(s). We will exploit the availability of bilingual learning environments in Oxford and Barcelona. In Barcelona, there is ready access to bilingual infants learning both Spanish and Catalan (two Romance languages sharing many cognates). In Oxford, there is a sufficiently large number of bilingual Spanish and English families. Spanish and English have fewer cognates and offers a critical contrast to the Barcelona context.Experiments: We will use new experimental paradigms, pioneered on monolingual infants in the Oxford BabyLab, that employ well-understood eye-tracking and neuro-imaging techniques. The methods developed with monolingual infants are ideally suited to exploring our research questions. The tasks involve infants looking at pictures at the same time as they hear speech. By monitoring their eye-movements and recording their brain activity, we hope to discover important clues as to how their two languages influence their reaction to the pictures they see. An important methodological advantage of this project is that it will follow infants' performance in a longitudinal manner - at 18, 24 and 30 months of age. A longitudinal design allows us to consider the substantial individual differences observed between infants in their vocabulary development and to apply sophisticated and powerful statistical analyses to the data collected on the project. We will also test monolingual infants on exactly the same set of studies as our bilingual population, thereby providing the appropriate baseline against which to assess the bilingual infants.Modelling: The purpose in constructing a neural model is to understand the mechanism that underlies observed behaviour. Current bilingual computational models only consider adult (large and stable) vocabularies. We will develop the first computational model of early bilingual learning. Recently, we have shown how developmental changes in the self-organising processes in neural network models of word learning can capture important aspects of infant behaviour. We will translate these modelling insights from monolingual infant word learning and recognition to infant bilingual development, in a manner that honours the results of our experiments.