Brain Connectivity in Depression

This study will include 60 subjects with medication-refractory depression undergoing transcranial magnetic stimulation (TMS) to the left dorsal lateral prefrontal cortex (DLPFC). In order to obtain good quality data and account for attrition, 80 subjects will be recruited. Subjects will be recruited from the Clinical Program of FDA approved TMS at the Berenson-Allen Center and the Butler TMS Clinic (40 per site). Subjects will undergo an hour-long MRI scanning session, an optional DNA-sample collection, up to three 20 minute neuronavigation sessions for marking the site of TMS stimulation, questionnaires, and a behavioral testing battery before and after their TMS treatment course. The task battery will last 45-60 minutes and consist of the Emotion Conflict Resolution (ECR) task, Multi-Source Interference Task (MSIT), War Game (Gambling) task, and Associative Learning with Reversal task. Subjects' scores on the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI) will also be assessed before and after the TMS course. MRI data will be utilized to identify brain regions whose connectivity to the stimulation site co-varies with the aforementioned objective measures of symptom improvement.