anhedonia

n. Diminished ability to experience pleasure. Anhedonia is one of two essential symptoms of a major depressive episode in the DSM-IV-TR (the other essential symptom is depressed mood; to have a major depressive episode, the patient must have either depressed mood or anhedonia) and the International Statistical Classification of Diseases and Related Health Problems-10 (ICD-10). Anhedonia in depression is described as an experience of no longer enjoying things that used to give one pleasure (e.g., taking walks, favorite foods, spending time with friends). Therefore, in depressed individuals anhedonia is thought to be a "state" experience - that is, once the depression (and symptom of anhedonia) lifts, the individual should find things enjoyable again. In schizophrenia, anhedonia is a common "negative" symptom and is thought to be more "trait" oriented, or a set personality feature.    - DGa