Effectiveness of deep brain stimulation in alleviating treatment-resistant schizophrenia: a systematic review

The complexity of schizophrenia, particularly in cases resistant to traditional pharmacological treatments, poses significant challenges for clinicians and researchers. This systematic review synthesizes existing evidence on the effectiveness of deep brain stimulation in treating treatment-resistant schizophrenia. Utilizing the PRISMA 2020 guidelines, a comprehensive literature search was conducted in March 2025 using the “Connected Papers” tool and other sources such as Web of Science, PubMed, PsycINFO, Embase, and Scopus, focusing on studies related to “deep brain stimulation,” “treatment-resistant schizophrenia,” and “refractory schizophrenia.” Four studies met the eligibility criteria, revealing that deep brain stimulation targeting specific brain regions, particularly the nucleus accumbens, can lead to significant symptomatic improvements in approximately 30% of patients unresponsive to conventional antipsychotics. Despite ten adverse events recorded across thirteen procedures, deep brain stimulation offers potential benefits for select individuals. While not universally superior to existing treatments, deep brain stimulation could inform clinical practice and decision-making, highlighting its role in multidisciplinary treatment frameworks. The findings underscore the importance of innovative therapeutic approaches in psychiatry and suggest broader implications for neuromodulation techniques across various psychiatric and neurological disorders, promoting personalized and effective treatment paradigms in mental healthcare.

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