International Study to Predict Optimized Treatment - in Depression

This study is for adults with major depression who have not yet tried certain antidepressant medications. Researchers are looking for patterns in brain activity and cognitive (thinking) tests that might predict which antidepressant medication works best for a particular person. The goal is to help doctors choose the right treatment for each patient from the start, rather than through a process of trial and error. You may be eligible if: - You have been diagnosed with major depressive disorder (MDD) - Your depression score on the Hamilton Rating Scale is 16 or higher (indicating moderate to severe depression) - You are between 18 and 65 years of age - You are fluent in English or Dutch You may NOT be eligible if: - You are currently having thoughts of suicide - You have bipolar disorder, psychosis, or a primary eating disorder - You have previously used or are currently using antidepressants, specifically escitalopram, sertraline, or venlafaxine XR - You have had a head injury that caused you to lose consciousness - You have serious problems with your vision, hearing, or hand movement that would prevent you from completing tests Talk to your doctor about whether this trial might be right for you.