The goal of this study is to learn whether 5 days of accelerated intermittent theta burst stimulation (iTBS), a rapid form of transcranial magnetic stimulation (TMS), which is a non-invasive procedure that uses magnetic fields to stimulate brain activity, works to treat depression in adults.

The main questions it aims to answer are:

• Does accelerated iTBS reduce depressive symptoms compared to sham (placebo) stimulation?
• Are there measurable brain, biological, and digitally measured emotion changes associated with treatment response?

Participants will:

• Be randomly assigned to receive either active iTBS or sham stimulation
• Receive 10 stimulation sessions per day for 5 consecutive days (total of 50 sessions)
• Complete MRI brain scans and EEG recordings before and after treatment
• Provide blood and saliva samples to measure biological markers
• Complete depression rating scales and questionnaires at baseline, during treatment, and at follow-up visits
• Use a secure mobile app to record brief facial and vocal samples during the 5-day treatment and at follow-up visits
• Return for follow-up visits at 1 week and at 1, 3, 6, and 12 months after treatment

Inclusion Criteria:

• English speaking
• Able to provide informed consent
• 18-65 years old
• Meets MDD criteria per the Mini International Neuropsychiatric Interview (MINI)

Exclusion Criteria:

• Unable to consent (due to medical condition, acute psychosis, substance use, etc)
• Use of benzodiazepines or medications that would interfere with TMS treatment as per PI discretion
• Active substance use or severe substance use that in the opinion of the PI would interfere with study participation
• Untreated, active psychosis
• Female patient who is breastfeeding, pregnant or who is planning a pregnancy during the study
• Contraindications to receiving TMS and/or MRI as determined by screening questionnaires
• Participation in any clinical study with exposure to any investigational treatment or product within the previous 30 days, or plan on concurrent participation in other studies.

De-identified individual participant data (IPD) of the results reported in publications may be made available upon reasonable request. Requests will be reviewed by the Principal Investigator to ensure that the proposed use is scientifically appropriate and consistent with participant consent and institutional policies.