Mental state language and quality of conversational experience in deaf and hearing children

Deaf children from hearing parents show a protracted delay in their performance on standard ‘theory of mind’ measures that concern their knowledge of false beliefs and other reality incongruent mental states. Considerable evidence indicates that children’s early experience of adults’ mental state talk predicts their later social cognitive development. However, no previous study has analyzed access to conversation about mental states in very young deaf children. We compared the conversational input of hearing parents to young deaf and hearing children aged 17 to 35 months in the UK and Sweden. Parents of hearing children used far more cognitive mental state language with their infants and their conversations were characterized by more communicatively effective turn-taking than parents of deaf children. These findings indicate that conversational input about mental states to very young deaf children differs significantly in those areas of interaction thought to be crucial for later social cognitive development and this difference is robust across two different cultures