A narrative review of non-invasive brain stimulation techniques in neuropsychiatric disorders: current applications and future directions

Background Neuropsychiatric disorders significantly burden individuals and society, necessitating the exploration of innovative treatment approaches. Non-invasive brain stimulation techniques have emerged as promising interventions for these disorders, offering potential therapeutic benefits with minimal side effects. This narrative review provides a comprehensive overview of non-invasive brain stimulation techniques' current applications and future directions in managing neuropsychiatric disorders.Methods A thorough search of relevant literature was conducted to identify studies investigating non-invasive brain stimulation techniques in neuropsychiatric disorders. The selected studies were critically reviewed, and their findings were synthesised to provide a comprehensive overview of the current state of knowledge in the field.Results The review highlights the current applications of non-invasive brain stimulation techniques in neuropsychiatric disorders, including major depressive disorder, Parkinson's disease, schizophrenia, insomnia, and cognitive impairments. It presents evidence supporting the efficacy of these techniques in modulating brain activity, alleviating symptoms, and enhancing cognitive functions. Furthermore, the review addresses challenges such as interindividual variability, optimal target site selection, and standardisation of protocols. It also discusses potential future directions, including exploring novel target sites, personalised stimulation protocols, integrating with other treatment modalities, and identifying biomarkers for treatment response.Conclusion Non-invasive brain stimulation techniques offer promising avenues for managing neuropsychiatric disorders. Further research is necessary to optimise stimulation protocols, establish standardised guidelines, and identify biomarkers for treatment response. The findings underscore the potential of non-invasive brain stimulation techniques as valuable additions to the armamentarium of neuropsychiatric treatments.