Dimensional Approach to Evaluate Reward Processing in Major Depressive Disorder Pre- and Post-Desvenlafaxine Treatment

Anhedonia (the lack of pleasure in normally pleasurable things) is a common symptom of major depressive disorder (MDD), and it may impact how patients with depression experience reward. Understanding how anhedonia is related to the experience of reward may help improve how depression is treated. Computer tasks can be used to measure how reward is experienced, and these measures might be able to predict things like who is likely to become depressed, or who will respond to antidepressant medication. Studying the relationship between anhedonia and reward in patients with depression might also tell us something about how to improve diagnosis and treatment of other psychiatric disorders.This is an open label controlled treatment study lasting 8 weeks. The brain scans will be used to find changes in brain areas that may be related to how people perform on the tasks. The investigators goal is to use this information to help us find a reliable predictor that can be used to guide MDD treatment.