Bilingual Babbling: Evidence for Language Differentiation in Dual Language Acquisition

In this study, we examined the babbling of a pre-verbal child who was learning English and French simultaneously. There were three overarching goals to the research: 1) To examine evidence for language differentiation during pre-lexical stages of bilingual acquisition; 2) To examine whether the time course of phonological development during the pre-verbal stages of bilingual acquisition is in line with that of children exposed to only one language or whether there are delays as a result of dual language exposure and learning; and 3) To examine evidence for babbling drift (Brown, 1958; Weir, 1966), that is, the notion that the babbling of pre-verbal children exhibits features of the target language system as the child approaches the stage of first-word productions. We regard these results as preliminary since further analyses must be done before we can provide a comprehensive picture of this child’s development and because acoustic analyses of certain features must be carried out to complement our phonological analyses. Moreover, analyses of additional children will be important to demonstrate the generalizability of these findings. A central issue in research on bilingual acquisition is when neuro-cognitive differentiation of two languages occurs in children exposed to two languages from birth (Genesee, 1989). Early conceptualizations argued that children exposed to two languages from birth go through an initial stage when there is a single linguistic system, comprised of fused subsystems (e.g., Volterra & Taeschner, 1978). However, recent evidence in our lab and other’s indicates that differentiation is evident in the one-word stage of bilingual development onward (see Deuchar & Quay, 2000; Genesee, 2001; and Meisel, 2001, for reviews). Evidence for differentiation can be found in lexical, syntactic, and pragmatic