Contrastive input enhancement in captioned video for L2 pronunciation learning

Abstract

This study investigated the potential of input enhancement in captioned video to facilitate learners’ perceptual sensitivity to a difficult L2 vowel contrast (/æ/-/ʌ/). Participants were randomly assigned to two control and four experimental viewing conditions to explore the effects of audiovisual input (a 30-minute TV episode) on perceptual learning. Textual enhancement on captions highlighted target sounds contrastively (two colors) or non-contrastively (one color) in words transcribed orthographically or in IPA phonetic symbols. Learners’ /æ/-/ʌ/ perception gains were assessed through lexical and phonetic identification and discrimination tasks. Eye-gaze measures were used to determine the effectiveness of enhancement in drawing learners’ attention to the target contrast across viewing conditions. Perceptual learning was observed, although not always consistently across tasks and conditions.