1. Perceptual Adaptation to Foreign Accents by Second Language Learners
- Author
-
Hitoshi Nishizawa
- Abstract
Many studies evidence the flexibility of speech perception in the first language (L1), which allows rapid adaptation to unfamiliar foreign accents. Two influential studies by Bradlow and Bent (2008) and a follow-up study by Baese-Berk et al. (2013) found that increased variability as a function of the number of talkers and accents facilitated the generalization of adaptation across talkers and accents by L1 listeners. However, very few studies have examined second language (L2) learners as listeners (Baese-Berk, 2018). Thus, little is known about perceptual flexibility in L2. Critically, there has been no study directly examining the effect of increased variability on adaptation to foreign accents by L2 listeners. My goal with this study is to address this research gap by closely following these studies with L2 listeners. I examine if variability facilitates adaptation to unfamiliar foreign accents by L2 listeners.To do this, I recruited 280 Japanese learners of English for a two-day experiment that consisted of a pre-test, treatment, and post-test. For the pre-test and post-test, I used a Mandarin talker and a Vietnamese talker. The participants were randomly assigned to seven groups and received different treatments: an identical-talker group, single-medium group, single-high group, single-low group, multi-talker group, multi-accent group, and control group. The identical-talker group had the same Mandarin talker as the tests. The rest of the groups had a different talker from the tests. The single-medium group featured one Mandarin talker with a similar level of intelligibility to the test talkers, while the single-high group had a high intelligibility Mandarin talker, and the single-low group had a low intelligibility Mandarin talker. The multi-talker group had five Mandarin talkers. The multi-accent group had five L2 accents that included the Mandarin accent but not the Vietnamese accent. The talkers in the multi-talker and multi-accent groups featured similar intelligibility levels to the single-medium talker. The control group had five American L1 talkers. In the pre-test, treatment, and post-test, the L2 listeners transcribed short sentences. Accuracy of word recognition was used as a measure of adaptation. The results showed no statistically significant improvements in any of the groups. Numerically however, the control group and the single-high group improved more than others for the Mandarin talker, while the single-medium and multi-talker groups improved more than others for the Vietnamese talker. The small improvements suggest possible differences in the mechanism of adaptation to foreign accents between L1 and L2, which may be modulated by listeners' proficiency. I discuss how speech perception theories and hypotheses that were developed within studies on L1 listeners and L2 phoneme acquisition theories may or may not explain the results. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]
- Published
- 2024