Defense Mechanism is an unconscious psychological strategies brought into play by various entities to cope with reality and to maintain self-image. Healthy persons normally use different defenses throughout life. An ego defense mechanism becomes pathological only when its persistent use leads to maladaptive behavior such that the physical and/or mental health of the individual is adversely affected. The purpose of ego defense mechanisms is to protect the mind/self/ego from anxiety, social sanctions or to provide a refuge from a situation with which one cannot currently cope.
Because of anxiety provoking demands created by the id, superego and reality, the ego has developed a number of defense mechanisms to cope with anxiety. Although we may knowingly use these mechanisms, in many cases these defenses work unconsciously to distort reality.
Structural model: The id, ego, and superego
The concept of id impulses comes from Sigmund Freud’s structural model. According to this theory, id impulses are based on the pleasure principle: instant gratification of one's own desires and needs. Sigmund Freud believed that the id represents biological instinctual impulses in ourselves, such as aggression (Thanatos or the Death instinct) and sexuality (Eros or the Life instinct). For example, when the id impulses (e.g. desire to have sexual relations with a stranger) conflict with the superego (e.g. belief in societal conventions of not having sex with unknown persons), unsatisfied feelings of anxiousness or feelings of anxiety come to the surface. To reduce these negative feelings, the ego might use defense mechanisms (conscious or unconscious blockage of the id impulses).
Freud also believed that conflicts between these two structures resulted in conflicts associated with psychosexual stages.
Definitions of individual psyche structures
Freud proposed three structures of the psyche or personality:
Id: a selfish, primitive, childish,