Hybrid perceptual training to facilitate the learning of nasal final contrasts by highly proficient Japanese learners of Mandarin

Native speakers of Japanese experience challenges in differentiating Mandarin nasal finals, even after years of experience with Mandarin. We used a hybrid perceptual training approach with highly proficient Japanese learners of Mandarin to improve their ability to distinguish nasal final contrasts, which are not distinctive in Japanese. Eight learners participated in a 6-day adaptive and high-variability perceptual training procedure, including a pre-, mid-, and posttest on categorisation of nasal finals, whereas eight control participants received the same three tests without the intervening training. No significant prepost performance changes were observed in the controls, whereas the trainees achieved an overall 13% improvement in identifying nasal final contrasts and better categorisation of nasal final continua. Additionally, they showed better generalisation to untrained nasal finals in both citation form and continuous speech. These findings suggest that hybrid adaptive and high-variability perceptual training helps facilitate highly proficient foreign learners' formation of non-native phonological representations.