Discrimination of foreign language speech contrasts by English monolinguals and French/English bilinguals

The primary aim of this study was to determine whether late French/English bilinguals are able to utilize knowledge of bilabial stop contrasts that exist in each of their separate languages to discriminate bilabial stop contrasts from a new language (Thai). Secondary aims were to determine associations between bilabial stop consonant production in the L1 and the L2, between language learning factors and production and discrimination, and to compare English bilinguals' and monolinguals' discrimination. Three Thai bilabial stop consonant pairs differentiated by Voice Onset Time (VOT) (combinations of [b], [p], and [ph]) were presented to 28 French-English bilinguals, 25 English-French bilinguals, and 43 English monolinguals in an AX discrimination task. It was hypothesized that L2 experience would facilitate discrimination of contrasts that were phonemic in the L2 but not in the L1 for bilinguals. Only limited support for this hypothesis was found. However, results indicate that high production proficiency bilinguals had higher discrimination of the phonemic L2 contrasts (non-phonemic in L1). Discrimination patterns indicate lasting L1 influence, with similarity between unknown foreign language contrasts and L1 contrasts influencing discrimination rates. Production results show evidence for L2 influence in the L1. Results are discussed in the context of current speech perception models.