Meta-analysis of the Effectiveness of Transcranial Electrical Stimulation Interventions on Executive Function and Mathematical Performance in children with Specific Learning Disorder

Learning disorder is a neurodevelopmental disorder that leads to difficulties in learning and performance of reading, writing, and mathematics. Transcranial electrical stimulation is one of the recent interventions that has been used in this group. The current paper aimed to systematically combine the findings of the existing studies to find the effectiveness of these brain stimulation interventions in improving the executive functions and mathematical performance of individuals with learning disorders, as well as the possible moderating variables using the meta-analysis method.  

The statistical population of the research was all published studies including scientific articles and theses. The systematic literature turned 21 studies in the meta-analysis, and 64 effect size Cohen’s ds were extracted and analyzed using CMA3 software.

The findings showed a significant moderate combined effect size in both fixed and random effects models. Moreover, the effect size of the transcranial random noise stimulation was shown to be larger than the transcranial direct-current stimulation and transcranial alternating current stimulation. In addition, the meta-regression showed that age is a significant predictor and moderator with a better effectiveness in younger individuals.

These findings reveal that transcranial electrical stimulation, especially random noise method, as one of the effective interventions in improving the executive functions and mathematical performance of children with learning disorder.