| This thesis investigates the linguistic factors that mediate lexical access in bilinguals. A fundamental question regarding bilingualism is whether the bilingual lexicon has a language-specific organization (having independent or modular memory stores for each known language) or a language-non-specific organization (having an integrated memory store containing all known words in both languages). Previous studies have largely demonstrated that bilinguals simultaneously access representations from both languages during comprehension, thus adhering to the non-selective activation approach. However, the degree to which activation spreads across language representations has been found to depend on several mitigating factors, which are the focus of this research.;Chapter 3 (Libben et al., under revision) presents two experiments that use a similar sentence reading paradigm as that employed in Chapter 2, but tested English dominant English-French bilinguals reading in their native language. In Experiment 1, participants were presented only with English sentences while in Experiment 2, French filler sentences were also included. Results suggested that, when bilinguals read in their native language they are able to selectively access the context-appropriate language. However, in the presence of second language cues, non-selective spreading of activation occurs. The three experiments presented in Chapter 4 use behavioural techniques to test the generalizability of the findings reported in the previous two studies and investigate specific participant- and lexical-features that contribute to non-selective access patterns.;Together these studies argue for an integrated and context-sensitive bilingual language processing system where the semantic framework that is constructed during reading provides important top-down influences on lexical access of words that are cross-linguistically ambiguous. The theoretical and applied implications of these findings, as well as avenues for future research are discussed.;The three studies presented in this dissertation investigate access to words that exist across languages such as interlingual homographs (e.g., chat ---casual talk in English, cat in French) and cognates (e.g., film and piano, which are identical in English and French). In Chapter 2 (Libben & Titone, 2009), we investigate the effect of sentence context and semantic constraint on non-selective access for bilinguals reading in their second language, using eye-movement methodology. French-English bilinguals read English sentences containing cognates, interlingual homographs, or matched control words. Sentences provided low or high semantic constraint for target-language meanings. Results suggested that bilinguals, reading in their second language, show non-selective access to cross-linguistically ambiguous words during sentence reading, but that this activation is attenuated in high constraint contexts during later stages of processing. |
