Abstract
BACKGROUND: Transcranial direct current stimulation (tDCS) and virtual reality (VR) have emerged as promising non-invasive interventions in treating psychiatric disorders. Despite their individual efficacy in improving symptoms of various psychiatric conditions, the understanding of the combined use of tDCS and VR is limited. This review aims to evaluate the clinical effects and mechanisms of combined tDCS and VR in treating psychiatric disorders. METHODS: We conducted a PRISMA 2020-compliant systematic review, searching major databases (PubMed, Web of Science, Scopus, PsycINFO, ScienceDirect, Cochrane Library, Google Scholar, medRxiv and ClinicalTrials.gov) for studies from January 2000 to July 2025 that evaluated combined tDCS-VR in psychiatric populations. Eligible clinical trials were screened, with tDCS/VR parameters and clinical outcomes extracted, and randomized controlled trials appraised using the Cochrane Risk of Bias 2 tool. RESULTS: Fourteen studies met inclusion criteria: seven reviews and seven empirical trials (five randomized controlled trials, two pilot/feasibility studies) using mainly 1-2 mA prefrontal tDCS paired with disorder-congruent VR. In post-traumatic stress disorder (PTSD) and specific phobias showed short-term symptom reductions, with some PTSD benefits maintained up to 12 months. Evidence for social anxiety and mild cognitive impairment-related depression was limited to single small RCTs with transient or inconsistent improvements. Overall confidence in the evidence is limited by small sample sizes, variable protocols, and risk‑of‑bias concerns. CONCLUSION: Although seven small, heterogeneous studies indicate that combined tDCS-VR is feasible and shows preliminary therapeutic promise-most consistently in PTSD and, to a lesser extent, in specific phobias-the overall evidence base remains limited. Mechanistic findings suggesting modulation of medial and ventromedial prefrontal-amygdala circuits are still exploratory. Given substantial methodological heterogeneity, small sample sizes, and risk of bias, tDCS-VR should be regarded as experimental. The larger, well‑designed, disorder‑tailored randomized controlled trials using standardized stimulation/VR protocols, mechanistic outcome measures, and efforts to identify predictors of response are required before routine clinical implementation.