Flexibly choosing a language in bilingual contexts lets bilingual children use all their linguistic resources, potentially enabling richer expression than single language contexts permit. This study aims to (1) assess whether bilingual children benefit from using all their languages, (2) explore how language balance and executive functioning relate to dual language management, and (3) examine the link between language mixing in an experimental task and daily life. To address these aims, bilingual children (English-Dutch, Polish-Dutch, Turkish-Dutch; n = 49) aged 4–7 years participated in a semantic verbal fluency task under three conditions: an either-language condition (free use of both languages) and two single-language conditions (restricted to children’s dominant or non-dominant language). Language balance was based on children’s proficiency in both languages. Executive functioning measures comprised selective attention and working memory. Results revealed a small, non-significant increase in word production in the either-language condition versus the single-language conditions. Children with stronger attention produced more words overall. In the either-language condition, balanced children with high attention skills benefited most. In contrast, balanced children with more limited attention skills struggled in the single-language conditions. Children switched more in the either-language condition. Switching in the task did not correlate meaningfully with daily language mixing. In summary, the either-language condition provided only minor benefits, with attention playing a key role and interacting with contextual requirements and language balance. The findings highlight the complexity of bilingual language use and caution against overgeneralizing experimental results to settings in daily life.
Blom et al. (Sat,) studied this question.