Dysfunctional Reward Processing in Depression.

Anhedonia - diminished pleasure and/or decreased reactivity to pleasurable stimuli - is a core feature of depression that frequently persists after treatment. As a result, extensive effort has been directed towards characterizing the psychological and biological processes that mediate dysfunctional reward processing in depression. Reward processing can be parsed into sub-components that include motivation, reinforcement learning, and hedonic capacity, which, according to preclinical and neuroimaging evidence, involve partially dissociable brain systems. In line with this, recent findings indicate that behavioral impairments and neural abnormalities in depression vary across distinct reward-related constructs. Ultimately, improved understanding of precise reward-related dysfunctions in depression promises to improve diagnostic and therapeutic efforts in depression.