Interaction of native- and second-language vowel system (s) in early and late bilinguals

age The objective of this study was to determine how bilinguals' age at the time of language acquisition influenced the organization of their phonetic bilingualism system(s). The productions of six English and five Korean vowels by English and Korean monolinguals were compared to the productions of the same individual differences vowels by early and late Korean-English bilinguals varying in amount of exposure to their second language. Results indicated that bilinguals' age profoundly influenced both the degree and the direction of the interaction Korean between the phonetic systems of their native (L1) and second (L2) languages. In particular, early bilinguals manifested a bidirectional L1-L2 influence and vowel systems produced distinct acoustic realizations of L1 and L2 vowels. Late bilinguals, however, showed evidence of a unidirectional influence of the L1 on the L2 and produced L2 vowels that were "colored" by acoustic properties of their L1. The degree and direction of L1-L2 influences in early and late bilinguals appeared to depend on the degree of acoustic similarity between L1 and L2 vowels and the length of their exposure to the L2. Overall, the findings underscored the complex nature of the restructuring of the L1-L2 phonetic system(s) in bilinguals.