Development of theory of mind in deaf and hearing children: the effects of communicative experiences

Abstract

The present study investigated understanding of false beliefs in deaf and hearing children. Two nonverbal false belief tests were used to compare deaf children (mean age: 5.2) with two groups of hearing children. The comparison of deaf and hearing children attending preschool (mean age: 5.0) who are matched in terms of spatial cognitive skills showed that hearing children were performing better than deaf children even when tested nonverbally. However deaf and hearing children without preschool experience (mean age: 4.8) who are matched in terms of their parental education level, but not spatial cognitive skills did not differ. Two verbal false belief tests were also used for hearing children Hearing children with preschool experience performed better than the ones without preschool experience in both nonverbal and verbal false belief tests. Skill in spatial cognition was found to be a mediating variable between preschool experience and verbal false belief understanding. The level of dialogical communication during a play session between mother and child was found related to performance on the verbal false belief test in hearing children. Although no association was found between false belief understanding and the number of mental state terms produced by the mothers of deaf and hearing children, there was a significant correlation between the number of mental state terms produced by the mothers and the children. The results are discussed with regard to the effects of language and conversational competence in the acquisition of a theory of mind.Key words: theory of mind, deaf children, preschool, nonverbal false belief tests, spatial cognition skills.