The effect of bilingualism on semantic processing

虽然在理解双语对语言处理的影响方面取得了很大进展，但关于双语如何影响语义处理和结构，仍有很多有待了解的地方。此外，研究刚刚开始探索双语者之间的个体差异，如习得年龄和熟练程度，如何影响语义功能。我的研究计划将通过三组实验来解决这些问题。

While much progress has been made in understanding the effects of bilingualism on language processing, much remains to be understood about how bilingualism impacts semantic processing and structure. Moreover, research has just begin to explore how individual differences between bilinguals, such as age of acquisition and proficiency, might affect semantic function. My program of research will address these questions through three sets of experiments. The first set of experiments will use event-related potential (ERP) and behavioural methodologies to study the influence of semantic information from each language on word processing in bilinguals. Specifically, I will examine the effects of semantic richness on word recognition. Semantic richness refers to the amount of information associated with a word; previous research (including mine) has demonstrated that words with more information associated to them are processed more efficiently. I will examine (a) whether bilinguals use semantic richness information in the same way as monolinguals; and (b) whether semantic information from the language that is not in use (non-target language) affects processing of the target language. For example, are items of high French semantic richness processed more efficiently in English? The second set of experiments will study the neurocognitive profile of bilinguals of differing second language proficiency, age of acquisition, and use, and examine how this profile affects language performance. I will use behavioural and ERP methodologies to examine (1) the effects of age of acquisition, proficiency in the second language, and current use of the second language, on performance in tasks assessing language and executive function, and (2) the interaction between executive function and language performance in bilinguals. The third set of experiments will use computational modeling to examine the semantic structure of the bilingual lexicon, or how different informational sources drive semantic access and processing. Specifically, we will use distributional models to analyze the contributions of age of acquisition, and second langauge proficiency and current use to performance on verbal fluency and visual lexical decision. This research program will provide important new information about the impact of language experience on language processing. While much research has explored the impact of semantic information on word processing in monolinguals, much less is known about the effects in bilinguals. Moreover, characteristics specific to bilinguals (age of acquisition, L2 proficiency and use) influence processing in both languages, in ways we are just beginning to understand. The research proposed here will answer these questions.