The sense of identification with either the male or female sex, as manifested in appearance, behavior, and other aspects of a person's life.
Influenced by a combination of biological and sociological factors, gender identity emerges by the age of two or three and is reinforced at puberty. Once established, it is generally fixed for life.
Aside from sex differences, other biological contrasts between males and females are already evident in childhood. Girls mature faster than boys, are physically healthier, and are more advanced in developing oral and written linguistic skills. Boys are generally more advanced at envisioning and manipulating objects in space. They are more aggressive and more physically active, preferring noisy, boisterous forms of play that require larger groups and more space than the play of girls the same age. In spite of conscious attempts to reduce sex role stereotyping in recent decades, boys and girls are still treated differently by adults from the time they are born. The way adults play with infants has been found to differ based on gender—girls are treated more gently and approached more verbally than boys. As children grow older, many parents, teachers, and other authority figures still tend to encourage independence, competition, and exploration more in boys and expressivity, nurturance, and obedience in girls.
A major step in the formation of gender identity occurs at about the age of three when children first become aware of anatomical differences between the sexes, usually through observation of siblings or peers. The awareness of physical difference is followed by awareness of the cultural differences between males and females and identification with the parent of the same sex, whose behavior the child begins to imitate. The most famous 20th-century theory about the acquisition of gender identity at this stage of life is the Oedipus complex formulated by Sigmund Freud (1856-1939). Like its female counterpart, which Freud termed the Electra complex, the Oedipus complex revolves around a child's wish to possess the parent of the opposite sex, while simultaneously wishing to eliminate the parent of the same sex, who is perceived as a rival.
In the Oedipus complex, the young boy develops incestuous desires toward his mother, while regarding his father as a rival for her affections. Fearing that the father will cut off his penis in retaliation—a phenomenon Freud called castration anxiety—the boy represses his forbidden desires and finally comes to identify with the father, internalizing his values and characteristics, which form the basis for the child's superego. In the female version of this theory, the young girl's discovery of sexual difference results in penis envy, which parallels castration anxiety in boys. The girl blames her mother for depriving her of a penis, and desires her father because he possesses one. As in the Oedipus complex, the girl eventually represses her incestuous desires and identifies with the same-sex parent (in this case, the mother).
The Oedipus complex has been widely criticized, especially by feminist critics who reject its assumption that "anatomy is destiny." One respected feminist theory is that of Nancy Chodorow, for whom the central factor in gender identity acquisition is the mother's role as primary caregiver, which leads to a greater sense of interrelatedness in girls, who identify with the mother and go on to reproduce the same patterns of mothering in their own adult lives, while boys, needing to identify with the parent of the opposite sex, acquire a defining sense of separateness and independence early in life. This "reproduction of mothering," being both biologically and sociologically determined, is at least theoretically open to the possibility of change if patterns of parenting can be altered.
The formation of gender identity has been approached in different terms by Lawrence Kohlberg (1927-1987), who formulated the concept of gender constancy, the awareness that gender remains fixed throughout a person's lifetime. Kohlberg noted that while children are aware of their own gender and the gender of others by the age of three, they do not really begin assuming appropriate gender-based behavior until the age of about seven, when they first understand that gender is permanent—that they cannot change gender the way they can change their clothes or their behavior. Kohlberg believed that children do not start systematically imitating the behavior of members of their own sex until that point.
While most people follow a predictable pattern in the acquisition of gender identity, some develop a gender identity inconsistent with their biological sex, a condition variously known as gender confusion, gender identity disorder, or transgender, which affects about 1 in 20,000 males and 1 in 50,000 females. Researchers have found that both early socialization and hormonal factors may play a role in the development of gender identity disorder. People with gender identity disorder usually feel from their earliest years that they are trapped in the wrong body and begin to show signs of gender confusion between the ages of two and four. They prefer playmates of the opposite sex at an age when most children prefer to spend time in the company of same-sex peers. They also show a preference for the clothing and typical activities of the opposite sex; transsexual males may show interest in dresses and makeup. Females with gender identity disorder are bored by ordinary female pastimes and prefer the rougher types of activity typically associated with males, such as contact sports.
Both male and female transsexuals believe and repeatedly insist that they actually are members of the opposite sex. They desire to live as members of the opposite sex, sometimes manifesting this desire by cross-dressing, either privately or in public. In some cases, adult transsexuals (both male and female) have their primary and secondary sexual characteristics altered through a sex change operation, consisting of surgery followed by hormone treatments.
Chodorow, Nancy. The Reproduction of Mothering: Psychoanalysis and the Sociology of Gender. Berkeley: University of Berkeley Press, 1978.
Diamant, Louis, and Richard D. McAnulty, eds. The Psychology of Sexual Orientation, Behavior, and Identity: A Handbook. Westport, CT: Greenwood Press, 1995.
Golombok, Susan, and Robyn Fivush. Gender Development. Cambridge: Cambridge University Press, 1994.