Bilingual advantage in vocabulary development: a longitudinal look at turkish-german preschoolers

Although extensive research has been conducted on bilingual vocabulary acquisition, there is still no consensus on how to assess vocabulary development in bilingual or multilingual children under three, given the complexity of learning words in two languages. This study investigates the developmental trajectories of productive and receptive vocabularies in 157 preschool-aged mono- and bilingual children aged 3 to 6, specifically focusing on Turkish-German bilingual children. We aimed to build on existing research to confirm and extend findings on vocabulary development in young bilingual children. Longitudinal data analysis revealed that bilingual children show weaker vocabulary skills in both modalities compared to same-aged monolinguals, yet demonstrate accelerated vocabulary expansion within a short timeframe. The vocabulary gap between bilingual and monolingual children is primarily thought to result from the more limited exposure to each language. The acquisition of language-independent conceptual knowledge may help facilitate transfer effects, allowing bilingual children to experience accelerated vocabulary growth under favorable exposure conditions, thereby helping them to gradually close the vocabulary gap.