Dissertation Title: Perceptual flexibility during second language learning: the role of language experience in Korean-English bilinguals’ pitch perception

Abstract: 

It is well established that native language speakers selectively tune into the most diagnostic acoustic parameters for contrasting sounds, and this process has impacts on their perceptual sensitivity (Francis & Nusbaum, 2002; Goldstone, 1994; Heeren & Schouten, 2008; Nosofsky, 1986). Recent work has converged to provide a great deal of evidence toward language-specific categorization by bilingual listeners, suggesting shared L1/L2 phonology system with phonetic properties of each sound established in language specific way (Dmitrieva, 2019; Elman et al., 1977; Grosjean, 1985; Hazan & Boulakia, 1993). While this work has predominantly examined changes in phonemic boundaries, there has been much less work examining language-specificity in cue-weightings or perceptual sensitivity. As these aspects of perception have primarily been explored through the lens of cumulative effects of long-term language experience, our understanding of short-term language experience, such as change in bilinguals’ language mode, remains largely unclear. The present study seeks to bridge this gap by examining the effects of language mode on the relative reliance on cues and perceptual sensitivity.

The current study examined perception of pitch by Korean-English bilinguals, building on evidence that pitch contrasts stop consonants in Korean, but not in English (Bang et al., 2018; Kong & Lee, 2018; Lisker & Abramson, 1964).This cross-linguistic differences in the use of pitch provides a testing ground to assess the extent of perceptual changes at the level of cue-weighting and perceptual sensitivity. Three research questions are posed:1) How does the contrastive use of pitch in L1 language warps perceptual sensitivity? 2) To what extent bilinguals’ perceptual patterns are affected by language mode? and 3) What is the relationships between L2 learning history and language-specific listening strategies?

In this experiment, Korean-English bilinguals and English monolinguals categorized and rated sounds varying in F0 and VOT in English and Korean mode. In addition, both groups discriminated pairs of sounds varying in F0 in small steps in each language mode. Listeners heard acoustically identical target stimuli, within language-specific experiment settings and instructions, in English and Korean modes. Results found that Korean-English bilinguals exhibited perceptual warping of pitch through acquired similarity. This perceptual warping was limited to listeners’ L1 Korean language mode. There was a significant correlation between L2 exposure and L1 cue-weighting. These results provide support for the localized warping model for perceptual sensitivities (Goldstone, 1994) and effects of L2 on L1 perception from ADAPPT model (de Leeuw & Chang, 2023)

Advisor Committee Chair: Dr. Melinda Fricke, Assistant Professor, Department of Linguistics at the University of Pittsburgh

Committee Members: Dr. Alan Juffs, Professor, Department of Linguistics; Dr. Claude E. Mauk, Teaching Professor, Department of Linguistics; and Dr. Seth Wiener, Associate Professor of Modern Languages.