Discrimination of American vowels in disyllables mixed in speech babble by experienced Japanese and Russian learners of English.

Abstract

Previous studies in this laboratory examining speeded discrimination of American English (AE) vowels in quiet by Japanese (JP) and Russian (RU) late L2 learners indicated differences in relative difficulty of non‐native contrasts that were predictable from L1 phonological differences. Response latencies were a sensitive measure of continuing L2 perceptual difficulties. In the present study, the same task (a speeded categorial ABX task with disyllabic stimuli) was administered to Japanese and Russian listeners, with stimuli mixed in speech babble at three levels (SNR 0, 6, 12). Eight experimental contrasts (four with spectral plus duration differences and four with spectral differences only) and four control contrasts were tested in lists with both vowel contrast and noise level varying randomly. Results indicated that both L2 groups performed more poorly than native AE control subjects on many of the experimental contrasts, including those differentiated by duration as well as spectral differences. Again differences in relative perceptual difficulty across L2 groups emerged. Perceptual assimilation patterns and performance on a test of English fluency and pronunciation (versant) were correlated with discrimination performance across individuals. [Work supported by NSF.]