The impact of bilingual language learning on whole-word complexity and segmental accuracy among children aged 18 and 36 months.

This study investigates the phonological acquisition of 19 monolingual English children and 21 English?French bilingual children at 18 and 36 months. It contributes to the understanding of age-related changes to phonological complexity and to differences due to bilingual language development. In addition, preliminary normative data is presented for English children and English?French bilingual children. Five measures were targeted to represent a range of indices of phonological development: the phonological mean length of utterance (pMLU) of the adult target, the pMLU produced by the child, the proportion of whole-word proximity (PWP), proportion of consonants correct (PCC), and proportion of whole words correct (PWC). The measures of children's productions showed improvements from 18 to 36 months; however, the rate of change varied across the measures, with PWP improving faster, then PCC, and finally PWC. The results indicated that bilingual children can keep pace with their monolingual peers at both 18 months and 36 months of age, at least in their dominant language. Based on these findings, discrepancies with monolingual phonological development that one might observe in a bilingual child's non-dominant language could be explained by reduced exposure to the language rather than a general slower acquisition of phonology.