Development of Theory of Mind in Children with Cochlear Implants: False Belief and Mental State Vocabularies

Objectives: The purposes of this study were to compare children with cochlear implants and children with normal hearing in terms of the performance of false belief task (FBT) and the use of mental state vocabulary test (MSVT), and to examine the relationship between their ability with these two tasks in each group.Methods: The subjects of the study were a total of 20 children–10 children with cochlear implants (CI) and 10 children with normal hearing (NH). For the FBT, 4 Maxi tasks and 4 Smarties tasks were presented. For the MSVT, the children were first presented with two stories and then were asked 20 questions to answer verbally.Results: The CI group showed lower performance both on the FBT and MSVT compared to the NH group. The difference of the FBT was statistically significant, but that of the MSVT was not. There was a correlation between mental state vocabulary use and the false belief task in each group. The mental state vocabulary used in the NH group was more diverse than in the CI group.Conclusion: Children with cochlear implants showed a lower performance on the false belief test and use of mental state vocabularies than their peers with normal hearing, even though they were in the same level according to a formal language test. The results of this study suggest that evaluation and intervention regarding Theory of Mind are necessary for children with CIs to have a successful social life through interaction with people around them.