Executive Functions and Theory-of-Mind Among Deaf Children: Different Routes to Understanding Other Minds?

Abstract

The aim of the present study was to investigate the role of executive functions (EF) in theory-of-mind (ToM) performance in deaf children and adolescents. Four groups of deaf children aged 7–16 years, with different language backgrounds at home and at school, that is, bilingually instructed native signers, oralist-instructed native signers, and two groups of bilingually instructed late signers from Sweden and Estonia, respectively, were given eight ToM and four EF measures. The bilingually instructed native signers performed at a significantly higher level on the ToM measures than the other groups of deaf children. On the EF measures, there were no significant differences found between any of the groups, with one exception—the Swedish bilingual late signers had a significantly shorter average reaction time on the go-no-go inhibition task than the oralist native signers and the Estonian bilingual late signers. However, the Swedish children's better EF performance was not mirrored in better performance on ToM tasks. Our results indicate that despite all deaf children's good general cognitive abilities, there were still differences in their performance on ToM tasks that need to be explained in other terms. Thus, whatever the cause of late signers' difficulties with ToM, poor EF-skills seem to be of minor importance.