Reduced affect

Reduced affect display, sometimes referred to as emotional blunting, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings (affect display) either verbally or non-verbally, especially when talking about issues that would normally be expected to engage the emotions. Expressive gestures are rare and there is little animation in facial expression or vocal inflection. Reduced affect can be symptomatic of autism, schizophrenia, depression, posttraumatic stress disorder, depersonalization disorder,schizoid personality disorder or brain damage. It may also be a side effect of certain medications (e.g., antipsychotics and antidepressants). Individuals with blunted or flat affect show different regional brain activity when compared with typical individuals.

Reduced affect should be distinguished from apathy, which explicitly refers to a lack of emotion, whereas reduced affect is a lack of emotional expression regardless of whether emotion is actually reduced or not.

Blunted affect is a lack of affect more severe than restricted or constricted affect, but less severe than flat or flattened affect. "The difference between flat and blunted affect is in degree. A person with flat affect has no or nearly no emotional expression. He or she may not react at all to circumstances that usually evoke strong emotions in others. A person with blunted affect, on the other hand, has a significantly reduced intensity in emotional expression".

Shallow affect has equivalent meaning to blunted affect. Factor 1 of the Psychopathy Checklist identifies shallow affect as a common attribute of psychopathy.

In making assessments of mood and affect the clinician is cautioned that "it is important to keep in mind that demonstrative expression can be influenced by cultural differences, medication, or situational factors"; while the layperson is warned to beware of applying the criterion lightly to "friends, otherwise [he or she] is likely to make false judgments, in view of the prevalence of schizoid and cyclothymic personalities in our 'normal' population, and our [US] tendency to psychological hypochondriasis".

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