Efficacy of Transcranial Direct Current Stimulation in the Treatment of Post-Stroke Aphasia: A Randomized Controlled Trial


  • Paveenrath Charussuriyong -
  • Rachawan Suksathien
  • Prinne Suvannang


transcranial direct current stimulation, aphasia, stroke, speech therapy, stroke rehabilitation


Objectives: To evaluate the efficacy of anodal transcranial direct current stimulation (tDCS) on improving language ability in patients with post-stroke aphasia

Study design: Double-blind randomized controlled trial

Setting: Department of Rehabilitation Medicine, Maharat Nakhon Ratchasima Hospital

Subjects: Post-stroke aphasia patients aged 18 years and over, with at least three months from stroke onset

Methods: Forty patients were randomly assigned to intervention and control groups. The intervention group received 2 mA of anodal tDCS over Broca’s area (F5) combined with speech therapy for 20 minutes per session per day on five consecutive days. The control group received sham-tDCS combined with speech therapy in the same protocol as the intervention group. Language skills were evaluated using the Thai Western Aphasia Battery at pre-treatment, post-treatment (after the session of the fifth day of treatment), and 1-month follow-up. The accessor was blinded.

Results: Thirty-two patients completed the assigned sessions. The mean age of the patients was 52.7 (SD=11.4) years. Most of them had an ischemic stroke (71.9%). The mean difference in Thai WAB-AQ scores between the intervention and control groups at post-treatment and 1-month follow-up were -0.05 (95% CI: -4.4, 4.3) and -2.38 (95% CI: -11.7, 6.9), respectively. However, the difference between the two groups did not reach statistical significance at either time point. No serious complication was found.

Conclusions: This study did not show sufficient evidence to support anodal tDCS concurrent speech therapy with additional improvement in language ability beyond those observed in patients undergoing speech therapy alone, among those with post-stroke aphasia.


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