Effects of bilingualism on foreign language learning during kindergarten years: investigating underlying mechanisms

Abstract This study examines the underlying mechanisms driving the bilingual advantage in learning English as a foreign language (EFL) among kindergarten-aged children. Participants included 85 Dutch-speaking monolinguals and 34 bilingual children. We assessed children’s English vocabulary and grammar as the outcome variables. Furthermore, phonological awareness, executive functions and motivation to learn English were measured as potential mediators of the bilingualism–EFL relationship. We also controlled for child age, non-verbal IQ, Dutch (majority language) proficiency, intensity of school English instruction, parental education and exposure to English activities. Results showed that bilingual children outperformed monolinguals in English receptive vocabulary, but only for noncognate words; no differences emerged for cognate words or English grammar. However, none of the proposed mediators explained this advantage. Findings are discussed in terms of why the effect was limited to vocabulary and potential alternative mechanisms not explored in the present study.