Defence mechanism

In psychoanalytic theory, defence mechanisms are unconscious psychological processes that protect the self from anxiety-producing thoughts and feelings related to internal conflicts and external stressors.

According to this theory, healthy people use different defence mechanisms throughout life. A defence mechanism can become pathological when its persistent use leads to maladaptive behaviour such that the physical or mental health of the individual is adversely affected. Among the purposes of defence mechanisms is to protect the mind/self/ego from anxiety or to provide a refuge from a situation with which one cannot cope at that moment.

Examples of defence mechanisms include: repression, the exclusion of unacceptable desires and ideas from consciousness; identification, the incorporation of some aspects of an object into oneself; rationalization, the justification of one's behaviour by using apparently logical reasons that are acceptable to the ego, thereby further suppressing awareness of the unconscious motivations; and sublimation, the process of channeling libido into "socially useful" disciplines, such as artistic, cultural, and intellectual pursuits, which indirectly provide gratification for the original drives.

Some psychologists follow a system that ranks defence mechanisms into seven levels, ranging from a high-adaptive defence level to a psychotic defence level. Assessments carried out when analyzing patients such as the Defence Mechanism Rating Scale (DMRS) and Vaillant's hierarchy of defense mechanisms have been used and modified for over 40 years to provide numerical data on the state of a person's defensive functioning.

In the first definitive book on defence mechanisms, The Ego and the Mechanisms of Defence (1936), Anna Freud enumerated the ten defence mechanisms that appear in the works of her father, Sigmund Freud: repression, regression, reaction formation, isolation, undoing, projection, introjection, turning against one's own person, reversal into the opposite, and sublimation or displacement.

Sigmund Freud posited that defence mechanisms work by distorting id impulses into acceptable forms, or by unconscious or conscious blockage of these impulses. Anna Freud considered defense mechanisms as intellectual and motor automatisms of various degrees of complexity, that arose in the process of involuntary and voluntary learning.

Anna Freud introduced the concept of signal anxiety; she stated that it was "not directly a conflicted instinctual tension but a signal occurring in the ego of an anticipated instinctual tension". The signalling function of anxiety was thus seen as crucial, and biologically adapted to warn the organism of danger or a threat to its equilibrium. The anxiety is felt as an increase in bodily or mental tension, and the signal that the organism receives in this way allows for the possibility of taking defensive action regarding the perceived danger.

Both Freuds studied defence mechanisms, but Anna spent more of her time and research on five main mechanisms: repression, regression, projection, reaction formation, and sublimation. All defence mechanisms are responses to anxiety and how the consciousness and unconscious manage the stress of a social situation.