Study on iTBS Regulating the Reward Circuit Function to Improve Anhedonia in Depression

Inclusion Criteria: 1. Aged 18-45 years, and right-handed; 2. Diagnosed with major depressive disorder (MDD) by at least two qualified psychiatrists, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), with a Montgomery-Åsberg Depression Rating Scale (MADRS) score ≥ 20 or a 17-item Hamilton Depression Rating Scale (HAMD-17) score ≥ 17; 3. Evaluated by a psychiatrist as having prominent anhedonia, and meeting the cutoff criteria on two self-report anhedonia scales, including a Snaith-Hamilton Pleasure Scale, Chinese version (SHAPS-C) score ≥ 20, or a Temporal Experience of Pleasure Scale, Chinese version (TEPS-C) score ≤ 76; 4. Medication type and dosage remained unchanged for at least 4 weeks prior to treatment initiation and throughout the study period; 5. MADRS item 10 score ≤ 4. Exclusion Criteria: 1. A history of epilepsy, seizures, stroke, or other serious organic brain diseases; 2. Presence of severe infectious diseases, malignant tumors, or other major unstable medical conditions; 3. Intellectual disability or developmental delay, presence of psychotic symptoms, or meeting the diagnostic criteria for other psychiatric disorders; 4. A history of substance abuse or psychoactive substance use; 5. Presence of intracranial implants (e.g., aneurysm clips, shunts, stimulators, cochlear implants, or electrodes), or any other metallic objects in or near the head that cannot be safely removed (excluding dental fillings); 6. Contraindications to MRI or structural intracranial abnormalities detected on MRI; 7. Pregnant or breastfeeding women; 8. Receipt of electroconvulsive therapy (ECT) within the past 6 months, or transcranial magnetic stimulation (TMS) within the past 3 months; 9. Current daily use of lorazepam \> 2 mg (or an equivalent dose), or use of antiepileptic drugs at any dose; 10. Presence of strong suicidal ideation, or a MADRS item 10 score \> 4.