Anhedonia in the context of "Clinical depression"

Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introduced by a group of US clinicians in the mid-1970s, the term was adopted by the American Psychiatric Association for this symptom cluster under mood disorders in the 1980 version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III), and has become widely used since. The disorder causes the second-most years lived with disability, after low back pain.

The diagnosis of major depressive disorder is based on the person's reported experiences, behavior reported by family or friends, and a mental status examination. There is no laboratory test for the disorder, but testing may be done to rule out physical conditions that can cause similar symptoms. The most common time of onset is in a person's 20s, with females affected about three times as often as males. The course of the disorder varies widely, from one episode lasting months to a lifelong disorder with recurrent episodes.

In psychology, adjustment is the condition of a person who is able to adapt to changes in their physical, occupational, and social environment. In other words, adjustment refers to the behavioral process of balancing conflicting needs or needs challenged by obstacles in the environment. Due to the various changes experienced throughout life, humans and animals have to regularly learn how to adjust to their environment. Throughout our lives, we encounter various phases that demand continuous adjustment, from changes in career paths and evolving relationships to the physical and psychological shifts associated with aging. Each stage presents unique challenges and requires us to adapt in ways that support our growth and well-being. For example, when they are stimulated by their physiological state to seek food, they eat (if possible) to reduce their hunger and thus adjust to the hunger stimulus. Successful adjustment equips individuals with a fulfilling quality of life, enriching their experiences as they navigate life’s challenges.

Adjustment disorder occurs when there is an inability to make a normal adjustment to some need or stress in the environment. Those who are unable to adjust well are more likely to have clinical anxiety or depression, as well as experience feelings of hopelessness, anhedonia, difficulty concentrating, sleeping problems, and reckless behavior.

Reduced affect display, sometimes referred to as emotional blunting or emotional numbing, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings either verbally or nonverbally, especially when talking about issues that would normally be expected to engage emotions. In this condition, expressive gestures are rare and there is little animation in facial expression or vocal inflection. Additionally, reduced affect can be symptomatic of autism, schizophrenia, depression, post-traumatic stress disorder, depersonalization-derealization disorder, schizoid personality disorder or brain damage. It may also be a side effect of certain medications (e.g., antipsychotics and antidepressants).

However, reduced affect should be distinguished from apathy and anhedonia, which explicitly refer to a lack of emotional sensation.