Type of bilingualism, task domain, and attention demands impact children’s cognitive performance.

Abstract

The present study investigated the relation between continuous measures of two qualitatively different types of bilingual experience and outcome measures that varied in domain (verbal or nonverbal) and processing demands (degree of conflict). Participants were 195 English-speaking children, 7 years old, who were enrolled in French immersion programs. Children were assessed for their degree of "home bilingualism," reflecting language use patterns at home, and "school bilingualism," reflecting progress in learning French. None of the children spoke French at home. Participants completed verbal fluency, n-back, and global-local tasks, with conditions within tasks varying in degree of attentional processing required. Type of bilingual experience affected verbal and nonverbal tasks differently. Home bilingualism was positively associated with performance on attentionally demanding conditions of the n-back and global-local tasks, the two nonverbal tasks, whereas school bilingualism was positively associated with performance on English verbal fluency, the linguistic task. In both cases, results were modulated by the degree of bilingual experience. These results underline the importance of specifying the type and degree of bilingual experience and the details of the outcome tasks to understand the impact of bilingualism on children's development. Public Significance StatementThe possibility that bilingualism impacts children's cognitive development is controversial, but parents must make crucial decisions about their children's linguistic environments despite the absence of clear evidence. However, bilingualism can be achieved in different ways and the outcomes can be measured in different domains. The present study compares the effect of bilingualism achieved through heritage language use at home and language education in school on verbal and nonverbal task performance. The results show specific effects of each form of bilingualism on each type of outcome, underlining the complexity of these relations.