Encyclopedia of Personality and Individual Differences

Living Edition
| Editors: Virgil Zeigler-Hill, Todd K. Shackelford

Defense Mechanisms

Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-28099-8_1372-1



Defense mechanisms (sometimes called adaptive mental mechanisms) reduce conflict and cognitive dissonance during sudden changes in internal and external reality. If such changes in reality are not “distorted” and “denied,” they can result in disabling anxiety and/or depression. Choice of defense is involuntary, but such choice can lead to enormous differences in mental health.

Defense mechanisms can restore psychological homeostasis by ignoring or deflecting sudden increases in impulse, affect, and emotion. Defense mechanisms can provide a mental time-out to adjust to sudden changes in reality or self-image. Defenses can mitigate sudden irresolvable conflict with important people, living or dead. Finally, defenses can mitigate conflict due to social learning or conscience.


The boundary between pathology and adaptation is ambiguous....


Defense Mechanism Personality Disorder Cognitive Dissonance External Reality Global Assessment Scale 
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Authors and Affiliations

  1. 1.Harvard Medical SchoolBostonUSA

Section editors and affiliations

  • Simon Boag
    • 1
  1. 1.MacQuarie UniversityNorth RydeAustralia