Neuromodulation techniques in obsessive-compulsive disorder: Current state of the art

Obsessive-compulsive disorder (OCD) is a chronic neuropsychiatric condition often resistant to conventional treatments such as cognitive behavioral therapy and pharmacotherapy. For treatment-refractory cases, neuromodulation techniques offer promising alternatives. This review provides an overview of recent advances in three major neuromodulation strategies: transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and deep brain stimulation (DBS). DBS has demonstrated robust efficacy across several brain targets, though clinical outcomes are influenced by interindividual variability in fiber anatomy, lead positioning, correct parameter adjustments, and symptomatology. Recent efforts focus on connectivity-based targeting, patient-specific imaging, and the development of closed-loop systems guided by electrophysiological and neuroimaging biomarkers. rTMS, a noninvasive neuromodulation technique, shows therapeutic potential but lacks consensus on optimal parameters and cortical targets, despite FDA approval of certain stimulation protocols. tDCS, while the most accessible modality, presents inconclusive evidence due to small sample sizes and heterogeneity in electrode montages. Overall, these neuromodulation techniques are rapidly evolving and hold considerable promise, but further high-quality studies are needed to standardize stimulation protocols, validate reliable biomarkers and tailor interventions to individual patient profiles. Personalized neuromodulation may represent the future of therapeutic strategies in OCD.