Individual Differences in L2 Speech Perception: The Role of Phonological Memory and Lipreading Ability

The current study investigated the effects of individual differences in lipreading ability, working memory (WM), and phonological short-term memory (PSTM) on second language (L2) speech perception. An L2 French vowel identification task was administered to 32 Australian English learners of French in audiovisual, audio-only, and visual-only conditions. Participants also completed tasks measuring their first language (L1) lipreading ability at the phoneme, word, and sentence level; a listening span task assessing their WM capacity; and a nonword repetition task assessing their PSTM. Overall, speech perception was significantly better in the audiovisual and audio-only conditions, and large individual variability was observed in the lipreading, WM, and PSTM tasks. Results revealed a significant effect of PSTM on vowel perception scores in all modalities of presentation, but no effect of WM capacity was found. In addition, lipreading ability at the word level was found to be a predictor of accurate L2 vowel perception in the visual modality.