Effects of transcranial direct current stimulation combined with speech therapy in two children with autism spectrum disorder: a clinical case series

Abstract

ABSTRACT | BACKGROUND: Transcranial direct current stimulation (tDCS) has shown promise as an adjunctive therapy for neurological and developmental conditions, including autism spectrum disorder (ASD). OBJECTIVE: To describe the preliminary effects of a tDCS protocol combined with traditional speech therapy in two children with ASD. METHODS: This case series involved two male children, aged 4-5 years, diagnosed with ASD. A total of 30 tDCS sessions (1mA, 30 minutes each) were delivered over 10 weeks (CP5–Fp2 montage), combined with language-focused speech therapy. Parents completed the Social Responsiveness Scale (SRS-2) before and after the intervention. RESULTS: Quantitative improvements were observed in social cognition, communication, and motivation, alongside reductions in restrictive behaviors. Qualitative gains included enhanced verbal intention, vocabulary, sentence construction, and emotional regulation. CONCLUSION: These findings support the feasibility and potential therapeutic benefit of combining tDCS with speech therapy in young children with ASD, warranting further investigation in controlled trials.