DOI: 10.6084/m9.figshare.28342510
title: Impact of phonological awareness intervention combined with transcranial direct current stimulation on rapid automatized naming and verbal short term memory in developmental dyslexia: a randomized controlled trial

description: This study evaluates the effects of phonological awareness (PA) and combined PA/transcranial direct current stimulation (tDCS) interventions to improve rapid automatized naming (RAN) and verbal short-term memory (VSTM) in developmental dyslexia. In this randomized, double-blind, sham-controlled clinical trial, we included a PA+sham tDCS group [Mean age: 9.54 (1.15), 71% male] and a PA+ active tDCS group [Mean age: 9.18 (1.30), 85% male] in which we applied tDCS over the left parieto-temporal junction. Each volunteer participated in 15 intervention sessions (session duration 60 min, 3 times per week × 5 weeks). Data of the groups over time were analyzed by a mixed model analysis of variance (ANOVA) with the between-subject factor group and the within-subject factor time. The PA intervention led to increased RAN and VSTM test scores in both groups after the end of interventions (<i>p</i> &lt; 0.05). tDCS had no further effect on outcome measures as compared to PA intervention alone. PA training is valuable to improve RAN and VSTM abilities in dyslexia. Anodal tDCS during the PA intervention had no further therapeutic effect on these skills. Therefore, the use of anodal tDCS over the left parieto-temporal junction is not recommended to improve RAN and VSTM functions in dyslexia. Phonological processing difficulties, including reduced phonological awareness, rapid automatized naming and verbal short-term memory are the leading cause of dyslexia.Phonological awareness training is beneficial to improve automatized naming and verbal short-term memory abilities in dyslexia.Transcranial direct current stimulation is an adjunctive method applied in reading studies to improve performance.This study showed the effectiveness of phonological awareness training on rapid automatized naming and verbal short-term memory abilities, but transcranial direct current stimulation did not have an additional effect on this improvement in the present study.Because of the limited effectiveness of transcranial direct current stimulation as adjunctive intervention in the treatment of dyslexia, rehabilitation professionals should use it conservatively.Rehabilitation professionals should use phonological awareness training to improve rapid automatized naming and verbal short-term memory instead of separate treatment of these deficits. Phonological processing difficulties, including reduced phonological awareness, rapid automatized naming and verbal short-term memory are the leading cause of dyslexia. Phonological awareness training is beneficial to improve automatized naming and verbal short-term memory abilities in dyslexia. Transcranial direct current stimulation is an adjunctive method applied in reading studies to improve performance. This study showed the effectiveness of phonological awareness training on rapid automatized naming and verbal short-term memory abilities, but transcranial direct current stimulation did not have an additional effect on this improvement in the present study. Because of the limited effectiveness of transcranial direct current stimulation as adjunctive intervention in the treatment of dyslexia, rehabilitation professionals should use it conservatively. Rehabilitation professionals should use phonological awareness training to improve rapid automatized naming and verbal short-term memory instead of separate treatment of these deficits.