Treating developmental dyslexia using transcranial stimulation combined with a reading stimulation program: A pilot study

Objective: Evaluate the effect of transcranial direct current stimulation (tDCS) combined with reading therapy on the performance of reading tasks in a serie of cases of children and adolescents with developmental dyslexia (DD). Method: (IRB/UNIFESP number:1281/2017). Four dyslexic students (two children and two adolescents) were evaluated with regards to rate and accuracy of reading fluency on three occasions: pre-intervention as well as one and six months after intervention. The intervention consisted of five consecutive sessions of active tDCS (1 mA for 20 minutes), followed by a two-day interval and another five sessions of tDCS combined with cognitive skills stimulation of phonological processing and decoding of words. Anodal tDCS was administered over the left parieto-occipital cortex, with the cathode placed over contralateral deltoid muscle. Each session was preceded by execution of semantic-lexical and phonological evocation tasks. Data were analyzed using Friedman test and JT method for analysis of clinical significance and the reliable change index. Results: Improvements were found in text reading rate and accuracy and word accuracy at the one-month and six-month evaluation. A significant increase was found in correct reading of words and pseudowords six months after intervention. Most of the improvements were reliable, with clinical significance in some cases. Conclusion: Transcranial direct current stimulation combined with a reading stimulation program proved effective at improving reading skills in these participants.