Comparison of the Efficacy of Accelerated Intermittent Theta Burst Stimulation and Accelerated Continuous Theta Burst Stimulation in Patients With Treatment-Resistant Depression

This study is comparing two forms of a brain stimulation treatment called theta burst stimulation (TBS) — an accelerated version that delivers multiple sessions per day — to see which works better for people with severe depression that hasn't responded to medication. TBS uses magnetic pulses to stimulate areas of the brain involved in mood. **You may be eligible if...** - You are between 18 and 65 years old - You have been diagnosed with major depressive disorder - Your depression has not improved after trying at least 2 different antidepressant medications - Your depression is currently severe (score of 20 or higher on standard depression scales) - You are right-handed - You have been on the same antidepressant at the same dose for the past 4 weeks **You may NOT be eligible if...** - You have a neurological condition (such as Parkinson's, multiple sclerosis, or a history of stroke) or significant medical illness like uncontrolled diabetes or kidney failure - You have a pacemaker, metal implants in your head, or other devices that could interact with magnets - You have a psychiatric diagnosis other than depression (e.g., bipolar disorder, schizophrenia) - You are pregnant or breastfeeding - You have severe depression with psychotic features (hallucinations or delusions) Talk to your doctor to see if this trial is right for you.