Abstract
We examined the perception of Japanese consonant length by three groups of Vietnamese speakers and a group of 10 Japanese speakers. Two of the Vietnamese groups consisted of learners of Japanese with one group participating in Vietnam (n = 17) and the other in Japan (n = 13). The third Vietnamese group consisted of 12 participants inexperienced in Japanese. Unlike Japanese, consonant length is non-contrastive in Vietnamese. Thus, we were interested in how different experience with Japanese may influence the perception of difficult Japanese contrasts. The overall mean discriminability in d-prime was 1.0, 1.9, 3.1 and 4.5 for the non-learner group, the learner group in Vietnam, the learner group in Japan and the native Japanese group, respectively. A clear difference between the two learner groups demonstrates learnability of Japanese consonant length for grownups. At the same time, the qualitative difference between the advanced learners and native Japanese speakers suggests genuine and persistent difficulty of Japanese consonant length. By providing additional empirical data beyond the segmental level, this study helps us to better evaluate the extent to which current theories of second language (L2) speech learning account for the acquisition of a wide range of L2 sounds by speakers from diverse first language backgrounds.
Acknowledgments
Portions of this work were presented at the 2nd International Conference on Tone and Intonation (TAI 2023) held in Singapore and the 5th International Symposium on Applied Phonetics (ISAPh 2024) held in Tartu, Estonia. We thank the editors and two anonymous reviewers for their thorough reading and insightful comments.
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Author contributions: Kimiko Tsukada was responsible for the conception and design of the work, the acquisition, analysis and interpretation of data for the work and writing of the paper. Đích Đào and Trang Le were responsible for the acquisition of data for the work. We agree to be accountable for all aspects of the work.
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Conflict of interest: The authors have no conflicts of interest to declare.
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Ethics statement: We received approval from the University of Oregon Institutional Review Board and the Macquarie University Research Office (human research ethics) to conduct this research. All participants gave informed consent before taking part.
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