Shyness as a risk factor for second language acquisition of immigrant preschoolers

•Shy immigrant children show lower second language competence than non-shy children.•A highly pronounced degree of shyness impairs local language acquisition.•The association between shyness and language is not moderated by the measurement method.

The aim of this study was to examine whether shyness is a risk factor for second language acquisition in immigrant preschoolers. Results from studies on first language acquisition indicate that shy children show less favorable language development; however, it remains unclear how shyness affects second language acquisition. As second language skills are often acquired in interactions outside the family where shyness is more evident, we postulate that shyness has a strong negative effect on second language acquisition. This hypothesis was examined using standardized tests and parental ratings in a sample of 330 immigrant preschoolers cross-sectionally and with 130 immigrant preschoolers longitudinally. The analyses revealed lower second language competence as well as slower language development in shy immigrant children compared to their non-shy counterparts. The present study highlights that not only contextual but also personality factors need to be considered for a comprehensive understanding of second language acquisition in immigrant children.