Is child-directed speech tailored to aid language development?

Because child-directed speech seems ubiquitous in certain cultures and because there is a positive association between language input and learning outcomes it has often been concluded that one function of child-directed speech is to aid children’s language development. I will address the logical fallacy behind this reasoning and report results of a scoping review of the research literature on child-directed speech that examined whether the existing evidence supports this conclusion. It shows that the limited evidence for this claim is confined to some very specific linguistic domains and learning tasks. Most research linking features of children’s language input to learning outcomes turns out to be agnostic about whether these features are exaggerated in child-directed speech. I will end by discussing how different mechanisms that may drive the production of child-directed speech can account for cultural diversity in its implementation.

This talk is part of Linguistic Circle - Invited talks on a range of Linguistics topics from high-profile speakers, organised by School of Philosophy, Psychology and Language Sciences - Linguistics and English Language department of the University of Edinburgh. It took place on 19th January 2023.