Reading and phonological awareness improvement accomplished by transcranial direct current stimulation combined with phonological awareness training: A randomized controlled trial

Abstract

Phonological awareness (PA) training is a core intervention in dyslexia. Recently, transcranial direct current stimulation (tDCS) has been probed as a complementary intervention for increasing reading ability in dyslexia, but not for enhancing the efficacy of PA. The aim of the current study was thus to examine whether tDCS combined with a PA intervention improves reading, but also PA abilities as a proxy in children with dyslexia. A randomized, double-blind, sham-controlled clinical trial was performed to assess the effects of tDCS (applied bilaterally over the temporo-parietal junction with the anode placed over the left, and the cathode placed over the right hemisphere) combined with PA training on reading and PA abilities in dyslexic patients. Twenty-eight participants were randomly assigned to active (PA + anodal tDCS) or sham (PA + sham tDCS) groups. Each subject participated in 15 treatment sessions. PA and real/non-word reading were evaluated at baseline before the intervention, at the end of the fifth, tenth, and final intervention sessions, and then 6 weeks after intervention. In the active tDCS group, the mean scores of non-word reading and PA tests were significantly improved during, immediately, and 6 weeks after the treatment, as compared to the sham tDCS group. tDCS is thus a promising complementary intervention if combined with PA training to enhance PA and reading abilities in dyslexia for an extended period after treatment.