A diminished ability to desire, seek, or take pleasure in experiences has a specific term in clinical literature, as well as its own measurement scales, and, according to the research framework used by the National Institute of Mental Health, its own distinct domain. The term is anhedonia. It is classified as a separate entity rather than simply the lack of positive mood.
This distinction underlies a claim currently being shared in a condensed form: that individuals who struggle to simply choose to feel better are not lacking in effort or gratitude. The evidence supports a more restricted version of this claim than the wording suggests. Treatment benefits most individuals, including those experiencing this symptom. The research indicates a symptom that generally shows slower and less complete improvement compared to the accompanying sadness, and that appears on different measurement tools.
We are writers, not healthcare professionals. What follows is an interpretation of the research, not medical guidance.
The origin of the term
The French psychologist Théodule Ribot introduced the term anhedonia in 1896, applying it to a complete loss of both physical and mental pleasure in cases of melancholia. It became a formal part of psychiatric diagnosis in the third edition of the Diagnostic and Statistical Manual, released in 1980, and continues to be included in DSM-5. A major depressive episode there requires five or more symptoms, with at least one being either depressed mood or a loss of interest and pleasure. Neither is individually required. Each can act as a pathway.
This framework has been in place for decades, and it is often the part most summaries overlook.
Researchers have since dissected the term. Kent Berridge and Terry Robinson’s research on reward established a distinction between wanting and liking, differentiating the attraction to something from the enjoyment derived from it. Der-Avakian and Markou, in their 2012 review in Trends in Neurosciences, outlined reward processing as involving motivation, consumption, and learning. In a 2011 paper in Neuroscience & Biobehavioral Reviews, Michael Treadway and David Zald argued that the psychiatric definition of anhedonia was too vague to be beneficial because it did not differentiate between consummatory and motivational deficits. A person can lose one while retaining the other, still taking pleasure in a meal once it is presented while struggling to create the motivation to prepare it.
The reasons for separate measurement from low mood
The separation began with questionnaires rather than brain imaging, and it predates neuroscience.
In 1988, David Watson, Lee Anna Clark, and Auke Tellegen published the Positive and Negative Affect Schedule in the Journal of Personality and Social Psychology: two ten-item mood scales. Across their development samples, the two scales showed correlations between minus 0.12 and minus 0.23, which the authors described as consistently low. In a psychiatric inpatient sample of 61 individuals, the correlation reached minus 0.27. Low, but not nonexistent. Reporting minimal positive feelings and reporting a significant amount of negative feelings turned out to be largely, though not entirely, distinct aspects to assess.
These are facts about self-reported items, not neural systems, and the two are frequently conflated in secondary accounts.
The NIMH framework establishes the separation structurally. Its Research Domain Criteria categorize Positive Valence Systems and Negative Valence Systems as distinct domains, with constructs under the first including reward responsiveness, reward learning, and reward valuation, and effort categorized beneath reward valuation. This framework is a hypothesis aimed at dissecting the issue, adopted by a funding agency due to the inadequacy of older diagnostic categories in yielding results. It structures research but does not provide definitive answers.
The clinical literature backs this assertion without finality. A 2025 review in Translational Psychiatry by Congchong Wu and colleagues at Zhejiang University School of Medicine compiles evidence indicating that individuals with major depression and significant anhedonia differ from those without it in symptom patterns, reported cognitive challenges, and responses to treatment. The review reiterates a background figure from a 2019 systematic review by Cao and colleagues in Progress in Neuro-Psychopharmacology and Biological Psychiatry, estimating that about 70 percent of people with major depressive disorder display clinical features of anhedonia. This figure serves as a summary statement rather than derived prevalence.