Prediction of the Therapeutic Response in Depression Based on Neuro-computational Modeling Assessment of Motivation

This study uses brain scans and computer-based tests to see if a person's motivation patterns (measured through brain activity) can predict which antidepressant medication will work best for them. Healthy volunteers are also enrolled for comparison. **You may be eligible if you have depression and...** - You have a current diagnosis of major depressive disorder that is moderate to severe - You need to start a new treatment (no previous antidepressant tried for this episode, or long enough off prior treatment) - You have valid health insurance **You may NOT be eligible if...** - You have treatment-resistant depression (failed 2 or more adequate antidepressant trials) - You have bipolar disorder, schizophrenia, dementia, or Parkinson's disease - You have contraindications to MRI (metal implants, claustrophobia) or are pregnant - You have a severe substance use disorder **Healthy volunteers** may also join if they have no mental health diagnoses, no neurological conditions, and can have an MRI. Talk to your doctor to see if this trial is right for you.