Effects of transcranial direct current stimulation on language recovery in chronic post-stroke aphasia

Background: Aphasia is a major cause of long-term disability in post-stroke patients. Non-invasive brain stimulation, particularly transcranial direct current stimulation (tDCS), has shown promise in enhancing language recovery. However, evidence from Indonesia remains scarce. This study aimed to evaluate the effects of tDCS on language recovery in chronic post-stroke aphasia (PSA). Methods: This quasi-experimental study included 30 patients with chronic PSA, divided into 2 groups: 15 received 5 sessions of tDCS combined with language training, while 15 underwent language training alone. Language abilities were assessed using the Tes Afasia untuk Diagnosis Informasi dan Rehabilitasi (TADIR) or Aphasia Test for Diagnostic Information and Rehabilitation at baseline, post-therapy, and 2 weeks post-therapy. Statistical analysis was conducted using the Friedman test. Results: Participants (93.3% male) had a median age of 56 years (range: 33-65 years). The tDCS group showed significant improvements in TADIR subtests, including verbal fluency, word naming, speech rate, verbal comprehension, and writing (P < 0.05). The control group showed improvements in fewer subtests, namely verbal fluency, word naming, and repetition. Conclusion: Combining tDCS with language training may enhance recovery in specific language domains, notably writing, among patients with chronic PSA. However, most between-group comparisons did not reach statistical significance, and findings should be interpreted as exploratory. Larger controlled trials are needed to establish the efficacy and clinical relevance of tDCS in aphasia rehabilitation.