The Effects of Short-Term Bilingual Exposure on Executive Functions, Theory of Mind, and Receptive Vocabulary in Monolingual Mandarin-Speaking Preschoolers

While the cognitive impact of long-term bilingualism has been extensively examined, less is known about the developmental outcomes of short-term bilingual exposure among young children in low-resource settings. This study examines the effects of short-term bilingual exposure on Executive Functions (EFs), Theory of Mind (ToM), and receptive vocabulary in monolingual Mandarin-speaking preschoolers from rural China. Sixty-five children (Mage = 53.4 months) were assigned to a 10-week English enrichment program (bilingual exposure group, n = 29) or a monolingual control group (n = 36). Pre- and posttest assessments measured inhibitory control, working memory, cognitive flexibility, ToM (via false-belief tasks), and Mandarin receptive vocabulary. Research Findings: Repeated measures ANCOVAs revealed a selective bilingual benefit. The bilingual group showed significant improvement in inhibitory control but not in working memory, cognitive flexibility, or ToM. Conversely, the monolingual group demonstrated greater gains in receptive vocabulary, suggesting a temporary differentiation in first language growth rates characteristic of the initial stages of emergent bilingualism. Practice or Policy: These findings underscore the positive impact of short-term bilingual exposure in fostering specific cognitive skills among rural preschoolers and highlight important implications for educational interventions in contexts where children often face limited opportunities for cognitive and educational enrichment.