Effect of transcranial direct current stimulation on dichotic listening test results in children with disorders of psychological development

IntroductionWe use dichotic listening (DL) test to assess functional brain asymmetry when we treat children with disorders of psychological development (DPD) by transcranial direct current stimulation (tDCS).AimIn this work we carry out retrospective analysis of children with DPD and study the influence of tDCS on auditory verbal stimuli perception characteristics obtained by DL tests.Material and methodsWe analyzed the DL test results of 6–13-year-old children; 26 children with specific developmental disorders of scholastic skills (SDDSS), 31 children with specific developmental disorders of speech and language (SDDSL), and 39 healthy children were tested. Some of the children with DPD (21 children) were tested only once, 26 – before and after tDCS, and 10 – before and after the treatment without tDCS. In all cases we estimated laterality indices (LI) and the amounts of “erroneous” answers (ErrA).Results and discussionIn the DPD group before the treatment the LI values were lower and the ErrA values were higher in comparison to the values of healthy children; the differences were more significant in the SDDSL than in the SDDSS subgroup. In the SDDSL subgroup after tDCS the LI values got closer to those of the healthy children, and the ErrA values decreased. The LI and ErrA values of children who had not received tDCS treatment did not change.ConclusionsThe DL test reveals the characteristics of brain asymmetry in case of DPD, and can be useful when planning tDCS treatment and estimating its effectiveness.