Training Japanese listeners to identify English /r/ and /l/: IV. Some effects of perceptual learning on speech production

This study investigated the effects of training in /r/–/l/ perceptual identification on /r/–/l/ production by adult Japanese speakers. Subjects were recorded producing English words that contrast /r/ and /l/ before and after participating in an extended period of /r/–/l/ identification training using a high-variability presentation format. All subjects showed significant perceptual learning as a result of the training program, and this perceptual learning generalized to novel items spoken by new talkers. Improvement in the Japanese trainees’ /r/–/l/ spoken utterances as a consequence of perceptual training was evaluated using two separate tests with native English listeners. First, a direct comparison of the pretest and post-test tokens showed significant improvement in the perceived rating of /r/ and /l/ productions as a consequence of perceptual learning. Second, the post-test productions were more accurately identified by English listeners than the pretest productions in a two-alternative minimal-pair identification procedure. These results indicate that the knowledge gained during perceptual learning of /r/ and /l/ transferred to the production domain, and thus provides novel information regarding the relationship between speech perception and production.