The Bilingual Acquisition of English and Mandarin: Chinese Childr ...

In addition, findings on speech and language perception in monolinguals indicate that newborn infants have general auditory discrimination capacities that adapt to the language they are exposed to. Infants can discriminate language-related signals, both segmental and suprasegmental, and these discriminatory abilities focus the child’s attention on acoustic information in the input that is relevant to the development of their native language (cf. Genesee, 2003). Bosch and Sebastián-Gallés (2001) reported that Spanish-Catalan bilingual infants can discriminate between their two native languages at 135 to 139 days of age, the same age at which monolingual children discriminate between these same languages. In other words, the bilingual children were the same as monolinguals in their discrimination capacities as a result of dual language exposure. There is evidence that infants’ impressive auditory discrimination and memory capacities are based on in utero language experiences during the last trimester. It appears that infants respond not simply to the mother’s familiar voice but rather to the general acoustic properties of the speech signal (DeCasper & Spence, 1986). Thus prosodic features could provide evidence of two languages for young infants, especially because speech heard in utero is low-pass filtered—that is, the infant in the womb will hear much more of the lower frequencies, the fundamental frequency that carries some prosodic features (Caroline Jones, personal communication, 20 August 2004). As for how soon and in what ways early experience affects the perceptual systems that underlie language acquisition, Janet Werker’s recent study has shown that babies who are exposed to two languages in utero are beginning the process of bilingual acquisition in the womb (Australian ABC Radio National, 2011).

This overemphasis on parental input has underestimated bilingual children’s capacity to absorb input from other sources, such as peer or sibling input and overheard conversations between other people—all of which play an important role in certain areas of monolingual children’s