UCLA

This dissertation examines the linguistic behavior of code-switching in three groups of highly proficient Cantonese-English bilinguals. Code-switching refers to alternating between two or more languages within the same sentence or between two sentences. While traditional research on bilingualism often compares bilingual speakers against monolinguals, assuming monolinguals as the baseline, this dissertation offers a new perspective by examining three distinct types of bilinguals characterized by their diverse language experience and cultural identities. The three groups include “homeland bilinguals” in Hong Kong, “heritage bilinguals” in the United States, and “immersed bilinguals” who were originally from Hong Kong but later migrated to the United States. Using cross-disciplinary psycholinguistic and sociolinguistic approaches, the dissertation addresses three central questions: (1) How does variation across language acquisition and sociocultural context influence speakers’ comprehension and production of words in the code-switching context? (2) What do code-switching practices reveal about the impact of linguistic structure? (3) What do differences in code-switching patterns across the three types of bilingual speakers reveal about the interaction between language experience, cultural identity, cognition, and language processing broadly? It was hypothesized that language experience and cultural identity, two significant factors contributing to bilinguals’ lived experiences, fundamentally influence their cognitive and language processing. Two experimental studies (Chapters 3 and 4) were conducted to examine the mechanisms underlying code-switching comprehension and production from a quantitative perspective. The results revealed that cross-linguistic lexical interference was partially modulated by sentence contexts and phonological cues (i.e., whether a code-switched word followed Cantonese or English phonology). Additionally, another experiment demonstrated that switch costs (i.e., slower behavioral response times in switch trials compared to non-switch trials) were present in voluntary code-switching production but absent in comprehension. Overall, findings from these two studies suggest that individuals’ language experience modulates switch costs in production. In contrast, switch costs are modulated by a combination of language experience, cultural identity, and cognitive control to varying degrees in comprehension. This dissertation further explores the interplay of language experience and cultural identity on code-switching practices in naturalistic conversations from the variationist and socio-pragmatic perspectives (Chapter 5). Bilinguals with more hybrid cultural identities demonstrated greater flexibility in code-switching, as evidenced by their higher overall frequency of code-switching. These bilinguals also showed greater engagement in bi-directional code-switching between Cantonese and English and utilization of a broader range of grammatical categories in code-switching. Findings from the sociolinguistic interview shed light on the intricate relationship between bilinguals’ ethnic identity, language regulation, and code-switching practices, thereby contributing to a better understanding of the unaccounted variation identified in quantitative data analysis. This dissertation underscores the importance of incorporating sociocultural contexts into bilingualism research. It also contributes to developing an integrated psycholinguistic and sociolinguistic approach to provide a syncretic account of bilingual language processing, cognitive control, social interaction, and cultural identity through code-switching.