Language learning, recasts, and interaction involving AAC: background and potential for intervention.

For children with typical development, language is learned through everyday discursive interaction. Adults mediate child participation in such interactions through the deployment of a range of co-constructive strategies, including repeating, questioning, prompting, expanding, and reformulating the child's utterances. Adult reformulations of child utterances, also known as recasts, have also been shown to relate to the acquisition of linguistic structures in children with language and learning disabilities and children and adults learning a foreign language. In this paper we discuss the theoretical basis and empirical evidence for the use of different types of recasts as a major language learning catalyst, and what may account for their facilitative effects. We consider the occurrence of different types of recasts in AAC-mediated interactions and their potential for language facilitation, within the typical operational and linguistic constraints of such interactions. We also consider the benefit of explicit and corrective forms of recasts for language facilitation in conversations with children who rely on AAC. We conclude by outlining future research directions.