Executive functions in deaf and hearing children: The mediating role of language skills in inhibitory control

This study aimed to analyze one of the critical components of inhibitory control-the ability to suppress interference-in deaf and hearing children and to investigate the mediating role of language skills in this central component of executive functions. To this end, a cross-sectional study was carried out with 40 deaf children with and without cochlear implants (CIs) and 21 hearing children age 7-10 years. The ability to suppress interference was assessed with the children's version of the Attentional Network Test (child-ANT), and language skills were assessed with a computerized version of the Carolina Picture Vocabulary Test (CPVT), a receptive vocabulary test. As a measure of control of nonverbal cognitive abilities, we used the Test of Nonverbal Intelligence (TONI-2). The results showed that deaf children had lower nonverbal IQ than hearing children. In addition, deaf children, compared with hearing children and regardless of whether they used CIs, showed a lower range of receptive vocabulary and a poorer ability to suppress the interference of distractors in the child-ANT. Linear regression mediation analyses revealed that this more significant interference effect was mediated by receptive vocabulary level and not by hearing deprivation. These results are consistent with the hypothesis that language is one of the critical factors in the development of executive functions.