Mechanism of Action of Transcranial Magnetic Stimulation

Mechanism of Action of Transcranial Magnetic Stimulation

This is an observational neuroimaging study assessing the effects of TMS on the brains of patients with unipolar depression.

This project aims to use functional connectivity magnetic resonance imaging (fcMRI) to study patients with unipolar depression receiving TMS. Patients will be scanned before and after a full course of TMS and clinical measures for depression severity and memory will be obtained at the same times.The project has the following aims and hypothesis: (1) to determine the therapeutic antidepressant mechanism of action of TMS at the circuit level (2) to study the use of fcMRI as a state biomarker for depression (3) to study the use of fcMRI as a predictor of response for depression.

Inclusion Criteria:

1. Males and females between the ages of 18-80
2. DSM-IV diagnosis of Depressive Episode
3. Patients requiring TMS treatment as part of their psychiatric care

Exclusion Criteria:

1. Comorbid DSM-IV primary diagnoses of schizoaffective disorder, schizophrenia or dementia.
2. Substance use disorder (abuse or dependence) with active use within the last 3 months
3. Severe or unstable medical illness.
4. MRI contraindications as determined by MGH department of radiology.