Input and Experience in Early Trilingual Development

Young children in Hong Kong and Guangzhou are speakers of Cantonese, Mandarin and English to different extents, ranging from monolinguals to highly proficient trilinguals. For families who use Cantonese and Mandarin regularly at home, nurturing trilingual competence in the child through early exposure to English is a much-welcomed concept. Despite the widespread practice of introducing English to toddlers through daily interactions at home, it is not clear whether and to what extent the relatively small amount of English input provided by the child’s caretaker can stimulate acquisition of English and impact on the other two languages, which are still developing.

The relation between language input and developmental outcome (“input-outcome relation”) is a key yet unresolved issue in psycholinguistic approaches to early trilingual development. For children being raised trilingually, their input in each language is likely to be reduced compared to their monolingual peers, but the few existing cases suggest that these children do not develop their languages more slowly than their monolingual and bilingual peers, and that the reported proportion of input in a language does not form a straightforward linear relation with the rate of acquisition in that language, pointing towards more accurate measures of input and a multi-factorial model of input-outcome relations. Building on the team’s previous research on bilingual children and a recent pilot study on a trilingual child, the study investigates input-outcome relations in Cantonese-Mandarin-English trilingual children and their monolingual peers in Hong Kong and Guangzhou for two years from 1;00 to 3;00 (N = 35). The quantity and quality of the caretaker input and the child’s acquisition of the languages will be documented, assessed and correlated systematically through an array of methods including Language Input Diary, web-based caretaker-child interaction recording, standardized parental reports, as well as direct cognitive and language assessment. Our innovative use of web-based methods incurs lower costs and offers greater flexibility and has the potential to transform research on caretaker-child interactions. The resulting database will generate highly accurate measures of fine-grained aspects of both the input and the outcome while controlling for the child’s executive functioning. The findings will be a crucial step towards a multi-factorial model of input-outcome relations in trilingualism, and for the very first time empirically address the probing questions raised by parents who are nurturing Cantonese-Mandarin-English trilingual children at home.