Effects of a short, intensive, multi-session tDCS treatment in developmental dyslexia: Preliminary results of a sham-controlled randomized clinical trial

Abstract

Developmental Dyslexia (DD) significantly interferes with academic, personal, social and emotional functioning. Nevertheless, established therapeutic options are still scarce. Research has begun to emerge studying the potential action of transcranial direct current stimulation (tDCS) for ameliorating reading. However, there are still open questions regarding the most suitable tDCS protocol in young with DD. The current study tested the effectiveness of a short, intensive and multi-session tDCS protocol and presented preliminary data from a randomized sham-controlled crossover trial. Twenty-seven children and adolescents with DD were randomly assigned to active tDCS or sham tDCS. Active tDCS group received five daily-consecutive sessions of left anodal/right cathodal set at 1mA for 20min over parieto-occipital regions. Reading measures, including text, high frequency word, low frequency word and non-word lists, were recorded before, immediately after the treatment and 1-week later. We found that only the active tDCS group ameliorated non-word reading speed immediately after and 1-week later the end of the treatment compared to the baseline. Some suggestions for the development of future tDCS protocols in children and adolescents with DD are given.

Keywords: Children; Neurodevelopmental disorders; Non-invasive brain stimulation; Reading; Specific learning disorders; Therapeutic intervention; Young.