Abnormality (behavior)

Abnormality, in the vivid sense of something deviating from the normal or differing from the typical (such as an aberration), is a subjectively defined behavioral characteristic, assigned to those with rare or dysfunctional conditions. Defining who is normal or abnormal is a contentious issue in abnormal psychology.

Several conventional criteria

A common approach to defining abnormality is a Multi-Criteria approach, where all definitions of abnormality are used to determine whether an individuals behavior is abnormal. For example, if an individual is engaging in a particular behavior that is preventing them from 'functioning', breaks a social norm and is statistically infrequent, then psychologists would be prepared to define this individual's behavior as abnormal. A good example of an abnormal behavior assessed by a multi-criteria approach is depression: it is commonly seen as a deviation from ideal mental stability, it often stops the individual from 'functioning' a normal life, and, although it is a relatively common mental disorder, it is still statistically infrequent; most people will not experience significant major depressive disorder in their lifetime 3.

References

1NIMH factsheet on frequency of mental disorders.
2Article on complicated grief.
3Article on results of the National Comorbidity Study

See also