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Defense Mechanisms

  1. Phebe Cramer

Published Online: 30 JAN 2010

DOI: 10.1002/9780470479216.corpsy0254

Corsini Encyclopedia of Psychology

Corsini Encyclopedia of Psychology

How to Cite

Cramer, P. 2010. Defense Mechanisms. Corsini Encyclopedia of Psychology. 1–2.

Author Information

  1. Williams College

Publication History

  1. Published Online: 30 JAN 2010


A defense mechanism may be defined as a cognitive operation or form of thinking that functions to protect a person from undue anxiety or loss of self-esteem. These mental mechanisms and their function operate outside of awareness, so that people do not realize why they are thinking in a particular way. For example, when Johnny says “Grandma doesn't like me” in the absence of any objective evidence that this is the case, it may well be that Johnny does not like his Grandma, but cannot recognize this emotion in himself, because it would be an unacceptable feeling. In this case, Johnny is attributing his own unacceptable feeling to someone else and would be displaying the defense mechanism of projection to hide his true feelings, while at the same time he is providing an explanation for why he avoids his Grandma.


  • defense mechanisms;
  • developmental hierarchy;
  • personality;
  • psychopathology;
  • stress