Comparing the Efficacy of fMRI-Guided vs. Standard iTBS in Treating Depression

This trial is comparing two types of transcranial magnetic stimulation (TMS) for treating depression: standard TMS (which targets a fixed brain area) versus fMRI-guided TMS (which uses brain scan data to personalize where the stimulation is directed). The goal is to see if a more personalized approach improves outcomes for people with major depressive disorder (MDD) who haven't responded to antidepressants. **You may be eligible if...** - You are 18 years or older and can speak and read English - You have been diagnosed with major depressive disorder without psychotic features in your current episode - You have not adequately responded to at least one antidepressant medication in the current episode - Your depression is moderate or severe (score ≥ 15 on the Hamilton Rating Scale) - Your doctor has referred you for TMS treatment - Your psychiatric medications have been stable for at least 4 weeks **You may NOT be eligible if...** - You have bipolar I or II disorder - You have a history of psychosis, epilepsy, or a metallic head implant or pacemaker - You currently use illegal drugs (other than medically prescribed cannabis) - You are pregnant or breastfeeding - You are acutely suicidal - You have a serious, unstable medical or neurological illness - You have previously failed electroconvulsive therapy (ECT) in the current episode Talk to your doctor to see if this trial is right for you.