Acoustic Analysis of Code-Switching Patterns in Multilingual Urban Communities

Thesis Abstract

This study investigates the acoustic characteristics and patterns of code-switching in multilingual urban communities, where linguistic dynamism significantly influences communication practices. As urban centers increasingly become melting pots of diverse languages, understanding the phonetic and prosodic features associated with code-switching phenomena can elucidate how bilingual and multilingual speakers navigate identity, social cohesion, and communicative efficiency. The primary aim is to analyze the acoustic properties of code-switched utterances and to identify patterns that distinguish them from monolingual speech within such communities. The study also seeks to explore how contextual factors—such as social setting, interlocutor identity, and conversational purpose—affect these phonetic features. The research objectives include (1) to document and compare acoustic features—such as pitch, formant frequencies, speech rate, and intonation contours—of code-switched versus non-code-switched speech; (2) to determine the influence of linguistic combinations (e.g., language A to language B switches) on acoustic variation; (3) to examine relationships between socio-demographic variables (e.g., age, education level) and code-switching patterns; and (4) to develop an acoustic profile of code-switching behaviors in the studied communities. The study hypothesizes that distinct acoustic signatures characterize code-switched speech, which vary systematically with linguistic context and social factors. Employing a mixed-methods research design, the study combines quantitative acoustic analysis with qualitative contextual insights. The population comprises approximately 500 multilingual residents in a major metropolitan city known for its vibrant linguistic diversity. A stratified random sampling technique was used to select 120 participants, balanced across age groups, gender, and language backgrounds. Data was collected via naturalistic conversations recorded in various settings—marketplaces, social gatherings, and workplaces—using high-fidelity digital audio recorders. An additional structured elicitation task was employed to induce controlled code-switching instances. Acoustic data were analyzed using Praat software to extract relevant features including fundamental frequency (F0), formant frequencies (F1, F2, F3), speech rate, and intonation patterns. These features were statistically analyzed using multivariate analysis of variance (MANOVA) to identify significant differences between code-switched and monolingual speech, as well as regression analysis to investigate predictors of acoustic variation. A mixed-effects modeling approach was employed to account for within-subject variability. The social and contextual factors influencing code-switching patterns were further explored through thematic analysis of interview transcripts and observational notes. Expected findings include identifiable acoustic markers—such as variations in pitch range, intonation contours, and speech tempo—distinguishing code-switched speech from monolingual utterances. Additional anticipated results involve variations in acoustic features based on the language pairs involved, speaker demographics, and contextual factors. These findings are expected to contribute quantitatively to the understanding of how multilingual speakers physiologically adapt their speech production during code-switching, thus offering a robust framework for future phonetic and sociolinguistic research. The theoretical foundation of this study incorporates the Speech Accommodation Theory and the Phonetic Convergence Model, which suggest that speakers modify their speech patterns to accommodate conversational partners and social contexts. By integrating these models with empirical acoustic data, the thesis advances knowledge of the phonetic mechanisms underpinning code-switching phenomena. Overall, this research provides valuable insights into the intersection between sociolinguistics and phonetics in multilingual settings. This study’s implications extend to language policy, speech therapy, and intercultural communication training within urban multilingual environments. Key contributions include the development of an acoustic profile of code-switching that can serve as a diagnostic tool for speech-language professionals and as a basis for technological applications such as improved speech recognition systems for multilingual contexts. Recommendations emphasize the importance of considering phonetic variability in language education, the design of language learning tools, and speech processing technologies. Future research should explore longitudinal patterns of acoustic change with increasing exposure to multilingual environments, further elucidating the dynamic nature of speech production in these settings.