Obsessive-Compulsive Disorder (OCD) is a chronic and often disabling neuropsychiatric condition that affects approximately 2–3% of the global population. It is characterized by intrusive, unwanted thoughts (obsessions) and repetitive behaviors (compulsions) that individuals feel driven to perform. While standard treatments such as selective serotonin reuptake inhibitors (SSRIs) and cognitive-behavioral therapy (CBT) are effective for many, up to 60% of patients experience inadequate response or intolerable side effects, leading to persistent symptoms and a significant reduction in quality of life.
In this context, Repetitive Transcranial Magnetic Stimulation (rTMS) has emerged as a promising, non-invasive neuromodulation technique for treatment-resistant OCD. It works by using magnetic pulses to stimulate specific regions of the brain implicated in the pathophysiology of OCD, particularly those within the cortico-striatal-thalamo-cortical (CSTC) circuits, including the dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC), supplementary motor area (SMA), and anterior cingulate cortex (ACC).
Repetitive Transcranial Magnetic Stimulation (rTMS) modulates brain activity by applying either low-frequency (LF ≤1 Hz) stimulation, which decreases cortical excitability, or high-frequency (HF ≥5 Hz) stimulation, which enhances activity. The selection of frequency and target region depends on the patient's symptom profile and brain activity patterns:
- Low-frequency rTMS over the supplementary motor area (SMA) or dorsolateral prefrontal cortex (DLPFC) aims to suppress hyperactivity associated with compulsions.
- High-frequency rTMS over the medial Prefrontal Cortex (mPFC) or anterior cingulate cortex (ACC) seeks to enhance underactive regulatory areas involved in executive function and emotion regulation.
Studies suggest that targeting the right dorsolateral prefrontal cortex (DLPFC) with low-frequency rTMS and the bilateral supplementary motor area (SMA) with inhibitory rTMS can lead to significant symptom improvement, often measured by reductions in Yale-Brown Obsessive Compulsive Scale (Y-BOCS) scores.
Several randomized controlled trials and meta-analyses have supported the efficacy of Repetitive Transcranial Magnetic Stimulation in reducing OCD symptoms:
- A network meta-analysis found that low-frequency rTMS over the dorsolateral prefrontal cortex (DLPFC) and supplementary motor area (SMA) was more effective than sham treatment.
- High-frequency rTMS over the anterior cingulate cortex (ACC) and medial Prefrontal Cortex (mPFC) has also shown efficacy, and the US FDA has approved this protocol for adults with OCD based on large-scale clinical trials.
Repetitive Transcranial Magnetic Stimulation (rTMS) is generally well-tolerated. The most commonly reported side effects include mild scalp discomfort or headache.
Clinical improvements are often observed after 10–20 sessions, with some studies
Repetitive Transcranial Magnetic Stimulation (rTMS) may be particularly beneficial for:
- Patients with treatment-resistant OCD
- Individuals with intolerance to medication side effects
- Those seeking a non-invasive, brain-directed treatment
- Patients experiencing executive dysfunction, intrusive thoughts, or persistent compulsions
Repetitive Transcranial Magnetic Stimulation (rTMS) represents a cutting-edge, evidence-based intervention for patients struggling with OCD who have not responded to conventional therapies. By targeting dysfunctional brain circuits through magnetic stimulation, Repetitive Transcranial Magnetic Stimulation (rTMS) offers a new therapeutic pathway that enhances brain plasticity, restores cognitive control, and reduces obsessive-compulsive symptoms.