16 Jul Cross-linguistic influence in simultaneous and early sequential bilingual children: a meta-analysis
How a bilingual child’s two languages affect each other has been a prominent topic of research in the field of bilingual first language acquisition over the past three decades. Such cross-linguistic influence, most commonly investigated at the level of (morpho)syntax, has been attested in both the spontaneous and elicited speech production of simultaneous bilingual children, as well as in their comprehension and judgements of sentences (see Serratrice, 2013, for an overview). Cross-linguistic influence is defined here as the overuse or overacceptance of (morpho)syntactic properties in bilingual children’s one language under influence of their other language. For example, Italian–English bilingual children have been found to overuse overt subject pronouns in Italian and this has been argued to result from cross-linguistic influence from English (e.g., Serratrice, Sorace & Paoli, 2004). Researchers have aimed to identify the contexts in which cross-linguistic influence is most likely to appear. Well-studied predictors of cross-linguistic influence include surface overlap, language domain, language dominance, and age (e.g., Foroodi-Nejad & Paradis, 2009; Hulk & Müller, 2000; Müller & Hulk, 2001; Sorace & Serratrice, 2009; Yip & Matthews, 2000).
Evidence for the contribution of these predictors is mixed, however. Cross-linguistic influence is not always found when predicted (e.g., Argyri & Sorace, 2007; Nicoladis, 2002, 2003) and it is sometimes found when not predicted (e.g., Foroodi-Nejad & Paradis, 2009; Strik & Pérez-Leroux, 2011). Furthermore, cross-linguistic influence varies from child to child, as evidenced by the large standard deviations found in many studies (e.g., Mykhaylyk & Ytterstad, 2017; Nicoladis, 2006). As a consequence, there is neither consensus on the extent to which cross-linguistic influence in bilingual language acquisition takes place, nor what predicts it. To shed light on these issues, we conducted a meta-analysis to systematically examine the effect of morphosyntactic cross-linguistic influence in relation to surface overlap, language domain, language dominance, and age.
Morphosyntactic development in bilingual children
Despite the many studies on the topic, the circumstances under which cross-linguistic influence emerges remain elusive. Cross-linguistic influence has been attested in various language combinations, for different linguistic properties, and using different tasks, but findings are inconsistent. Study outcomes can differ even when the same morphosyntactic property in the same language was under investigation (compare Rodina, Kupisch, Meir, Mitrofanova, Urek & Westergaard, 2020; Schwartz, Minkov, Dieser, Protassova, Moin & Polinsky, 2015). Various predictors of cross-linguistic influence have been identified to explain this variability. Typically, these have been discussed in relation to the presence of cross-linguistic influence – namely, whether certain conditions have to be met for cross-linguistic influence to occur – and in relation to the strength of cross-linguistic influence – namely, whether under certain circumstances the effect size of cross-linguistic influence increases.
In this study, we focus on four factors frequently studied in relation to cross-linguistic influence: (1) the type of surface overlap between bilingual children’s languages, (2) the language domains involved, (3) language dominance, and (4) children’s age.
Predictors of cross-linguistic influence
Surface overlap Language domain Language dominance Age
This meta-analysis is the first study to systematically assess the effect size of cross-linguistic influence in bilingual children and effects of surface overlap, language domain, language dominance and age. Overall, there was a significant effect of cross-linguistic influence across studies and its average effect size was small to moderate. Furthermore, the results of most of the studies were consistent with cross-linguistic influence. Cross-linguistic influence was stronger from children’s societal language into their non-societal language than vice versa. No effects were found for surface overlap – either as defined by the authors of the studies or based on the adult language system only – language domain, language dominance as operationalized by the authors of the studies, or age. These findings suggest that cross-linguistic influence is part and parcel of being bilingual and can manifest itself in various linguistic contexts.
VAN DIJK, C., VAN WONDEREN, E., KOUTAMANIS, E., KOOTSTRA, G., DIJKSTRA, T., & UNSWORTH, S. (2021). Cross-linguistic influence in simultaneous and early sequential bilingual children: A meta-analysis. Journal of Child Language, 1-33. doi:10.1017/S0305000921000337