Lack of funding to complete the trial phase of the study.

Current medical therapies for depression take weeks to achieve full efficacy, and are ineffective in many patients or cause intolerable side effects, emphasizing the need for a deeper understanding of depression and its treatment. Identifying early brain biomarkers of treatments responses seems necessary to improve antidepressant treatment outcome. In this study we aim to detect early brain responses to a fast acting antidepressant-like treatment administered intravenously during a Real-Time Neurofeedback functional magnetic resonance imaging (MRI) Task to predict antidepressant treatment outcome in depression. At completion of the neuroimaging task, participants will enter a placebo-controlled clinical trial with a selective serotonin reuptake inhibitor (SSRI).

Inclusion Criteria:

Inclusion criteria will include Hamilton Depressive Rating Scale (HDRS) scores >15 and Snaith-Hamilton Pleasure Scale scores (SHAPS) > 7.

Exclusion Criteria:

suicidal ideation, comorbid conditions that are medical, neurological or psychiatric, pregnancy, use of hormones (including birth control) or use of psychotropic agents. We will only permit certain past anxiety disorder diagnoses, including generalized anxiety, panic, agoraphobia, social phobia.

We will also exclude left-handed individuals and patients who have used any centrally acting medications, nicotine, or recreational drugs within the past 2 months.