Effects of transcranial electrical stimulation on academic and cognitive skills in individuals with specific learning disabilities: A systematic review

Abstract

There has been a rising interest in utilizing transcranial electrical stimulation (TES) techniques to induce neuroplasticity and modulate cognition in children and adults. Despite the escalating interest in non-pharmacological interventions in people with specific learning disabilities (SLD), there is a noticeable absence of a thorough and up-to-date review that consolidates studies of TES in individuals with SLD.A systematic literature search, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, was conducted across PubMed, Scopus, Web of Science, Google Scholar, and Embase databases, covering the period from 2000 to September 2024. Study eligibility criteria were pre-established using the Population, Intervention, Comparison, and Outcome (PICO) model. The grade of recommendation (GOR) for each learning disability was determined based on the level of evidence (LOE). Out of 1571 initial references, the screening resulted in inclusion of nineteen studies (17 dyslexia, 2 dyscalculia). The total number of participants in the included studies was 470, of which 249 were female (52.97 %) and 221 were male (47.03 %). The mean age of participants ranged from 9.5 to 33 years. Fifteen studies employed tDCS, one study used tACS and tRNS, and one utilized tRNS exclusively. TES interventions, especially tDCS, enhanced phonological awareness, improved reading accuracy, and reduced reading time in individuals with dyslexia. In those with dyscalculia, TES improved mathematical performance but did not demonstrate significant effects on cognitive skills. Findings suggest TES interventions, particularly tDCS, are beneficial for improving cognitive skills and reading performance in individuals with dyslexia.

Keywords: Cognitive skill; Dyscalculia; Dyslexia; Learning disabilities; Transcranial electrical stimulation.