Natural dynamics of caregiver-child affect are linked to communication and children’s word knowledge

Abstract

Children learn language in the context of rich social interactions that unfold in parallel with continuous emotional experiences. We investigated how fluctuations in affect are linked to caregiver-child communication and children’s word knowledge. Multi-day household audio recordings and densely-sampled ratings of affect revealed that children (24-30 months) were more likely to know words that they heard more often in contexts with higher valence or arousal. These moments were also associated with denser communication, relative to moments of lower valence and arousal. The amount of turn-taking surrounding word tokens partially mediated the relation between affect and word knowledge, suggesting that moments of higher valence or arousal facilitate word learning in part by supporting mutually engaging communication. This investigation expands the definition of word-learning contexts to include affective states and associated communicative behaviors, and underscores the importance of looking beyond linguistic communication to understand how children learn language.