Predictors of Theory of Mind performance in bilingual and monolingual children

Aims and objectives/purpose/research questions: The goal of the current study was to examine whether language and Executive Function (EF) skills predict Theory of Mind (ToM) performance in bilingual and monolingual children. Design/methodology/approach: Participants included 44 monolingual English-speaking children (M-Age = 7.03, SD = 1.23), 44 simultaneous English-Spanish bilingual children (M-Age = 7.36, SD = 1.18), and 27 English first language (L1) bilinguals (native English speakers learning Spanish through dual immersion programs; M-Age = 7.58, SD = 1.24). In the second-order false belief task, children were asked to reason about one character's thoughts about another character's thoughts. Three components of EF were measured: inhibition (via a flanker task); updating of working memory (via a Corsi blocks task); and shifting (via a card sort task). The Clinical Evaluation of Language Fundamentals 4th Edition indexed omnibus English language skills. Data and analysis: Separate logistic regression models were constructed to analyze the predictors of ToM performance for each group controlling for age, socioeconomic status, and non-verbal IQ. Findings/conclusions: Language ability, but not EF skills, predicted ToM performance in simultaneous bilinguals. In contrast, EF skills but not language predicted ToM performance in monolinguals and in English L1 bilinguals. Originality: This is the first study to show that children with distinct language acquisition histories approach verbal ToM problems differently.