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

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.