Effect of intensive audiovisual perceptual training on the perception and production of the /l/-/r/ contrast for Japanese learners of English

This study investigates (a) the extent to which L2 learners use phonetic information from visual cues to improve the perception of a novel phonemic contrast following a course of intensive perceptual training, and (b) the impact of perceptual training on pronunciation. 62 Japanese learners of English were initially tested on their perception of the /l/-/r/ contrast in audio, visual and audiovisual modalities, and then undertook ten sessions of intensive training, before being tested again. Eighteen were trained using auditory stimuli, 25 using natural audiovisual stimuli and 19 using audiovisual stimuli combining a synthetic face with natural speech. All three groups of learners showed a significant benefit of training but learners with audiovisual training did not show greater improvement than listeners with auditory training. The ‘Auditory-training’ group improved their auditory perception of the sounds to a greater extent than the AV-training groups, and the AV (natural face) trainees improved their sensitivity to visual cues to a greater extent than those trained with auditory or AV (synthetic face) stimuli. The learners’ pronunciation of /l/-/r/ consonants improved significantly following perceptual training, with a greater improvement seen for those trained audiovisually with natural stimuli.