Defence mechanism

A defence mechanism is an automatic, largely unconscious way the mind shields itself from anxiety, guilt or pain. Sigmund Freud introduced the idea, and his daughter Anna Freud set out the main mechanisms in her 1936 book The Ego and the Mechanisms of Defence. Later psychoanalysts added more and ranked them from less to more mature.

Common examples

• Denial — refusing to accept a painful fact, such as a diagnosis.
• Projection — seeing your own unwanted feelings in someone else.
• Rationalisation — giving a sensible-sounding reason for something done for other motives.
• Displacement — taking anger out on a safer target, such as shouting at the children after a row at work.
• Humour and sublimation — turning difficult feelings into jokes, work or creativity; usually counted as mature defences.

Defences are normal and often helpful in the short term. They become a problem when they are rigid and stop you facing something that needs attention — denying chest pain, for example, or a drinking problem. The concept comes from psychodynamic theory; therapists use it to understand behaviour, not as a diagnosis.