Language interaction in the development of speech rhythm in simultaneous bilinguals

This study aims to analyse facilitatory and inhibitory effects of bilingualism on first language acquisition of prosody. The speech rhythm produced by Spanish–English 2-, 4- and 6-year-old bilinguals was analysed acoustically and compared to adult and child monolingual baselines. Our results demonstrate that despite an even-timed bias for the production of vocalic materials also found for monolinguals, bilinguals do not show the anticipated uneven-timed bias in their consonant interval production. Bilinguals therefore follow a different developmental path from monolinguals with two rhythmically distinct languages at early stages of language acquisition. Rhythmic acquisition is characterized by language interaction, which leads to faster mastery of consonant interval durations, especially in the structurally more complex language, English. We argue that the interaction of languages in bilinguals and the subsequent transfer provides a developmental advantage to bilingual children leading to more fine-tuned motor control, and possibly more stable mental representations. We place the results in the context of the dynamic systems theory, which has the interaction of language subsystems as its main tenet.