Doctoral Dissertation Research: An ERP Investigation of Individual Differences in the Processing of Wh- Dependencies by Native and Non-Native Speakers

在我们这个多元化的社会里，多语言能力变得越来越重要，尽管人们对是什么让一个人成为一名优秀的第二语言学习者知之甚少。儿童相对容易地获得语言，而成年人则表现出熟练掌握第二语言的持续困难。人们假设认知能力增强的个体对语言的处理和理解能力更强，这表明认知能力的个体差异可能与成功的语言处理有关。本论文利用脑电研究认知能力的个体差异对第二语言理解的影响，重点研究英语母语者和英语母语者对复句的实时理解。使用大脑成像技术EEG来检查第二语言的处理过程，可能会提高我们对大脑在多大程度上能够自我重组以适应成年后一种新语言的理解。因此，该项目有望为更广泛地了解大脑可塑性的本质提供新的见解。这个项目考察了本族语和非本族语者的语言加工在多大程度上是定性相似的，检验了语言学习和语言加工中不同理论的预测。当参与者读到一句话时，比如“我想知道采访戴夫的编辑是谁”，他们必须搜索句子中“谁”这个词的来源位置，这种关系被称为wh依赖。参与者将阅读这样的句子，因为他们的大脑活动是通过脑电记录的，以便在整个句子中跟踪wh依赖的处理。该项目考察了学习者和本族语者对wh依存关系的处理在多大程度上涉及预测结构中尚未遇到的部分，以及这两组人是否只试图在语法允许的句子位置完成依存关系。所有参与者还将接受一系列认知测试的评估，以确定认知能力的个体差异如何影响母语和非母语的加工。使用脑电可以检验母语者和学习者是否使用性质相似的加工机制，以及加工过程是否在相似的时间进程中展开，从而提供了两个群体之间更准确的比较，并为成人第二语言(L2)习得的可能性和局限性提供了新的线索。

Multilingualism is increasingly important in our diverse society, although relatively little is known about what makes someone a 'good' second language learner. While children acquire language with relative ease, adults show persistent difficulty becoming proficient in a second language. It has been hypothesized that individuals with increased cognitive abilities are better able to process and comprehend language, suggesting that individual differences in cognitive abilities may be related to successful language processing. This dissertation uses electroencephalography (EEG) to examine how individual differences in cognitive abilities influence second language comprehension, focusing on how native English speakers and Chinese-speaking learners of English comprehend complex sentences in real time. Using the brain imaging technique EEG to examine the processing of a second language has the potential to advance our understanding of the extent to which the brain is able to reorganize itself to accommodate a new language in adulthood. Thus, this project holds promise for providing new insights regarding the nature of brain plasticity more broadly. This project examines the extent to which processing in native and non-native speakers is qualitatively similar, testing the predictions of alternative theories in language learning and language processing. When a participant reads a sentence like "I wonder who the editor interviewed Dave with," they must search for the position in the sentence from which the word "who" originated, a relationship that is referred to as a wh- dependency. Participants will read sentences such as these as their brain activity is recorded using EEG in order to track the processing of the wh- dependency throughout the sentence. The project examines the extent to which the processing of wh-dependencies in both learners and native speakers involves predicting parts of the structure that have not yet been encountered and whether both groups only attempt to complete the dependency in positions in the sentence that the grammar allows. All participants will also be assessed on a battery of cognitive tests, in order to determine how individual differences in cognitive abilities impact native and non-native processing. Using EEG allows for an examination of whether natives and learners use qualitatively similar processing mechanisms and whether processing unfolds on a similar time-course, providing a more precise comparison between the two populations and shedding new light on the possibilities and limitations of adult second language (L2) acquisition.