[Page 185]Anhedonia is a core symptom of multiple mental health disorders. Although the term anhedonia was originally defined as an inability to experience subjective pleasure (an + hedone, Greek for “without” + “pleasure”), contemporary conceptualizations have broadened the use of the term to encompass deficits in anticipation, motivation, cost-benefit decision making, and reinforcement learning, in addition to feelings of pleasure and positive emotionality. The clinical presentation and underlying pathomechanisms of anhedonia may therefore vary both interdiagnostically as well as intradiagnostically.

Since the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, anhedonia has been featured prominently in the classification of disorders such as major depression and schizophrenia, and it may also occur in the context of anxiety disorders and substance use disorders as well as other ...