Context-Guided Personalized iTBS for Depression

The goal of this randomized clinical trial is to learn whether context-guided personalized intermittent theta burst stimulation (iTBS) works better than standard iTBS for adults with major depressive disorder. iTBS is a noninvasive treatment that uses magnetic pulses to stimulate specific areas of the brain. Participants will be assigned by chance to one of two treatment groups. The standard treatment group will receive iTBS at a commonly used target in the left dorsolateral prefrontal cortex after watching a neutral video. The personalized treatment group will receive iTBS at an individual brain target selected using magnetic resonance imaging data. Before each treatment session, participants in this group will watch a positive emotional video intended to activate brain functions related to the selected target. Both groups will receive five iTBS sessions per day for five consecutive treatment days. Participants will continue their stable antidepressant treatment during the study. The main question is whether context-guided personalized iTBS results in a higher treatment response rate than standard iTBS two weeks after treatment. Treatment response is defined as a reduction of at least 50% from baseline in the 17-item Hamilton Depression Rating Scale score. Researchers will also compare early changes in depression, anxiety and other clinical symptoms, changes in brain imaging measures, and any side effects. Clinical and brain imaging assessments will be conducted before and after the treatment course, and clinical symptoms will be assessed again two weeks after treatment.

Inclusion Criteria: * Male or female outpatients or inpatients aged 18 to 55 years, inclusive. * Right-handed. * Diagnosis of major depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), confirmed using the Mini International Neuropsychiatric Interview (MINI). Both first and recurrent depressive episodes are eligible. * A 17-item Hamilton Depression Rating Scale (HAMD-17) total score of at least 14 at both screening and baseline. * At enrollment, participants may be antidepressant-free or may have received an antidepressant at no less than the minimum effective dose for at least 4 weeks. The antidepressant may be combined with no more than two other medications, and the type and dosage of medications must remain unchanged from enrollment until study completion. * At least primary school education and able to understand the study procedures and requirements. * Able to undergo magnetic resonance imaging and intermittent theta burst stimulation safely. * Voluntarily agrees to participate and provides written informed consent. Exclusion Criteria: * Serious or unstable medical or neurological illness. * Pregnancy or breastfeeding. * History of seizure, epilepsy, hydrocephalus, or central nervous system tumor. * Contraindication to magnetic resonance imaging, including claustrophobia, an electronic or metallic implant, or a non-removable metallic dental prosthesis. * Receipt of systematic modified electroconvulsive therapy, transcranial magnetic stimulation, deep brain stimulation, vagus nerve stimulation, or another physical neuromodulation treatment within 3 months before screening. * Excessive head motion during MRI scanning (rotation exceeding 3.0° and/or translation exceeding 3 mm) * Resting motor threshold remaining at or above 70% of the device maximum stimulator output after repeated testing, when the investigator considers continued treatment to present a safety concern.