'Wanting' is a component of anticipatory positive affect, mediating both the motivation (i.e. Re-conceptualizations of anhedonia highlight the independence of 'wanting' and 'liking'. While anhedonia was originally defined in 1896 by Théodule-Armand Ribot as the reduced ability to experience pleasure, it has been used to refer to deficits in multiple facets of reward. While the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) does not explicitly mention anhedonia, the depressive symptom analogous to anhedonia as described in the DSM-5 is a loss of interest or pleasure.

In the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5 ), anhedonia is a component of depressive disorders, substance-related disorders, psychotic disorders, and personality disorders, where it is defined by either a reduced ability to experience pleasure, or a diminished interest in engaging in pleasurable activities. While earlier definitions emphasized the inability to experience pleasure, anhedonia is currently used by researchers to refer to reduced motivation, reduced anticipatory pleasure (wanting), reduced consummatory pleasure (liking), and deficits in reinforcement learning. / ˌ æ n h i ˈ d oʊ n i ə/ AN-hee- DOH-nee-əĪnhedonia is a diverse array of deficits in hedonic function, including reduced motivation or ability to experience pleasure.

Synonyms for flat affect