Transcranial direct current stimulation (tDCS) for cognitive impairment in schizophrenia: A systematic review and meta-analysis of randomized controlled trials

Abstract

Cognitive deficits represent a core symptom domain in schizophrenia, with limited responsiveness to pharmacological interventions. Transcranial direct current stimulation (tDCS) has emerged as a promising non-invasive neuromodulatory technique targeting cognitive enhancement. This systematic review and meta-analysis synthesized randomized controlled trials (RCTs) assessing the efficacy of tDCS on cognitive outcomes in schizophrenia. A comprehensive literature search identified 33 RCTs (n = 1372) evaluating cognitive effects of tDCS in patients with schizophrenia or schizoaffective disorder. Studies varied in montage, intensity, duration, and session count. Risk of bias was assessed using the Jadad scale and Cochrane RoB 2 tool. Quantitative meta-analyses were Cognitive deficits represent a core symptom domain in schizophrenia, with limited responsiveness to pharmacological interventions. Transcranial direct current stimulation (tDCS) has emerged as a promising non-invasive neuromodulatory technique targeting cognitive enhancement. This systematic review and meta-analysis synthesized randomized controlled trials (RCTs) assessing the efficacy of tDCS on cognitive outcomes in schizophrenia. A comprehensive literature search identified 33 RCTs (n = 1372) evaluating cognitive effects of tDCS in patients with schizophrenia or schizoaffective disorder. Studies varied in montage, intensity, duration, and session count. Risk of bias was assessed using the Jadad scale and Cochrane RoB 2 tool. Quantitative meta-analyses were conducted across eight cognitive domains using multilevel random-effects models.