The effects of non-invasive brain stimulation on cognitive impairment in depression: A systematic review and meta-analysis.

BACKGROUND

Cognition is commonly compromised in depression, and non-invasive brain stimulation (NIBS) has been well-established in the treatment of depression, but its efficacy for treating cognitive deficit has not been fully elucidated. Based on the available evidence on NIBS, we conducted a meta-analysis to systematically assess the efficacy of NIBS in improving cognitive deficits in depressed patients.

METHODS

A literature search was conducted in PubMed, Web of Science, Embase, Ovid MEDLINE, and Cochrane Library databases up to February 20, 2025. we separately assessed the effects on: global cognitive function, learning and memory, working memory, language, psychomotor speed, attention, visuospatial ability, and domains of executive function (including attentional switching, verbal fluency, inhibitory control, and cognitive flexibility).

RESULTS

A total of 23 randomized controlled trials (n = 1267) were included in this study. Analyses showed that NIBS produced significant improvement in the domains of global cognitive function (SMD=0.24, 95 % CI [0.03, 0.46]) and learning and memory (SMD=0.46, 95 % CI [0.06, 0.85]). Subgroup analyses showed that transcranial magnetic stimulation (TMS) was significantly better than the placebo control group in terms of global cognitive function improvement (SMD=0.32, 95 % CI [0.07, 0.57]). However, other cognitive dimensions showed no significant improvement with NIBS

CONCLUSION

Our findings suggest that NIBS has significant efficacy on global cognitive function, learning and memory in depressed patients. Effects on other domains were not significant. Future high-quality studies are needed to validate which stimulation programs are most effective.