Vagus Nerve Stimulation (VNS) Electroencephalogram (EEG) Protocol Supplement

The purpose of this study is to examine the autonomic and physiologic effects of implanted VNS in treatment-resistant depression patients. To examine the neurophysiologic effects of Vagus Nerve Stimulation (VNS) in treatment-resistant depression.

Inclusion criteria

• Participants must be at least 18 years old.
• Participants must be able to read, understand and have the capacity to provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization.
• Proficiency in English sufficient to complete questionnaire and follow instructions during fMRI assessments and iTBS interventions.
• Willingness to comply with all study procedures and the ability to communicate with study personnel about adverse events and other clinically important information
• Participant must be currently enrolled in the REVEAL study and implanted with a VNS device for the clinical indication of Major Depressive Disorder (MDD)

a. Clinical Indication of MDD as defined: Participant has a diagnosis of chronic (≥ 2 years) or ≥ 4 recurrent depressive episodes as defined by DSM-5 criteria documented using the MINI criteria and psychiatric medical record review.

• For females of reproductive potential: use of highly effective contraception for at least 1 month prior to screening and agreement to use such a method during study participation.
• Access to ongoing psychiatric care before and after completion of the study.
• In good general health, as evidenced by medical history
• Agreement to adhere to Lifestyle Considerations throughout study duration.

Exclusion criteria

• Participant is pregnant
• Participant does not speak or read English
• Any other clinical reasons deemed by the investigator of the study for which the participant would not be an appropriate candidate for the study.
• Contraindication to MRI (ferromagnetic metal in their body)
• Contraindication to EEG
• Medication Contraindications