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

Patients with major depressive disorder Who May Qualify: - Meeting DSM-5 criteria for major depressive disorder (single or recurrent episodes) - With a MADRS score \>= 24 - For which a new line of treatment is needed - No previous line of antidepressant for this episode or wash-out long-enough to avoid carry-over effects - Valid health care insurance Who Should NOT Join This Trial: - Treatment-resistant depression (defined as insufficient response despite at least 2 trials of antidepressant prescribed at adequate dose and duration) - Subjects with a trial of escitalopram and/or vortioxetine for the current episode, or with contra-indication to one of these two drugs - Subjects with a diagnostic of persistent depressive disorder, bipolar disorder or schizophrenia, neurodeveloppemental disorder, unremitted substance abuse disorder other than tobacco, personality disorder severe enough to compromise the follow-up (based on investigator's appreciation). - Subject with a history of neurological disorder: parkinson's disease, dementia - Contraindications to MRI scanning: pregnancy, claustrophobia, metallic implants - Pregnant or breastfeeding women - involuntary hospitalisation and legal protection measures Healthy volunteers Who May Qualify: \- Valid health care insurance Who Should NOT Join This Trial: - Subjects with a diagnostic of persistent depressive disorder, bipolar disorder or schizophrenia, neurodeveloppemental disorder, unremitted substance abuse disorder other than tobacco, personality disorder severe enough to compromise the follow-up (based on investigator's appreciation). - Subject with a history of neurological disorder: parkinson's disease, dementia - Contraindications to MRI scanning: pregnancy, claustrophobia, metallic implants - Pregnant or breastfeeding women Always talk to your doctor about whether this trial is right for you.