Contemporary Theories of Sexual Orientation

Traditional theories on sexual orientation have argued for biological causation and then focused on finding evidence for this perspective in physiological and psychological studies. While some evidence suggests that biology may play some small role in sexual orientation development, theorists recognize the complex interplay between nature and nurture in the formation of both gender orientation and sexual orientation. After a discussion of research on gender orientation, this article presents a multidisciplinary review of the literature on sexual orientation development. As greater professional and public acceptance of homosexuality and bisexuality emerge in our culture, our awareness of the wide diversity of sexual expression is expanding.

Keywords Androphilia; Bisexual; Gonad; Gynephilia; Heterosexual; Homosexual; Monozygotic Twins; Neurology; Polysexual

Sex, Gender, & Sexuality > Contemporary Theories of Sexual Orientation

Overview

The nature versus nurture debate is a central theme in any review of contemporary theories of sexual orientation. It centers on the question of whether a person is born heterosexual or homosexual, or if people develop their sexual orientation through childhood interactions with family members and playmates. In part, the answer to this question depends upon how one approaches the issue. Experts in genetics, neurology, and related biological sciences tend to develop perspectives based upon more innate physical qualities that impact human behavior, while social scientists and psychologists tend to focus on human interactions as a basis of social development. Likewise, some individual scholars view one factor as causal in the development of sexual orientation, while others seek a more integrated theoretical analysis that considers several factors.

Thus, although the balance of this article looks at the various factors individually, it is important to consider how complex and interconnected biology and psychology can be. It is also important to consider how most scholars believe that one's sexual orientation is not a fixed or absolute concept. Rather, they believe that one's sexual orientation can differ over time and according to one's life experiences. Many people, for example, have had both homosexual and heterosexual experiences during their lifetime. And though a person may identify himself or herself as homosexual, heterosexual, or bisexual, even this self-definition may differ from that of an outside observer. In thinking about sexual orientation, therefore, it is important to keep one's mind open to the complexities of the human experience.

One important way to deepen our understanding of sexual orientation is to first expand our knowledge of gender orientation. Traditionally, people in Western cultures have believed that there are two genders: male and female. However, Harbeck (2007) and others have argued that "male" and "female" represent two extreme points on a continuum of gender identity. Their work suggests that this continuum can be described in an integrated theory that takes into account a variety of causal factors like:

• Genetic and other biological predispositions;
• Biological and environmental modifications (hormones, surgery, pollution);
• Developmental experiences (family, peers, social institutions);
• Psychological dispositions/trait factors (temperament, identity, lifespan);
• Social and cultural structures and process (masculinity, femininity, gender, and other learned behaviors); and
• Contextual factors (availability, acceptability).

The World Health Organization, for example, indicates that in approximately one out of every 2,000 births in this country, the baby is born visibly intersex. In these cases, a specialist in sex differentiation is to be consulted in order to begin the process of defining the baby's gender. Similar anomalies can be found in internal sex organs, genetic markers, and other neurological and biological materials. Scholars have referred to these conditions as "intersex" or "disorders of sex development," but those eager to abolish the negative connotations of these labels use the phrase "variations of sex development."

While we know that a significant number of individuals have physiological gender variations, little is known about the number of individuals who have psychological gender variations or identify with a gender variation. Additionally, we now know that environmental pollution plays a role in gonad function as well as in the sex development of various species such as green mussels, frogs, sea bass, roaches, rodents, and swallows (Nagarajappa, 2006; Thomas, 1982; Sitzlar, 2008). Thus, some scholars have begun arguing that gender may be more diverse than previously thought, and may even be becoming more diverse.

Thus, bridging the discussion of gender identity and sexual orientation is the topic of intersexuality or transgender identities. Transgender is an umbrella term that encompasses both transvestites and transsexuals. Transvestites are individuals who wear the clothing normally ascribed to the opposite gender in a given society, and adopt the stereotypical mannerisms associated with that gender. For example, a male transvestite might wear a dress, high heeled shoes, and makeup to adopt the persona of a woman. Individuals may engage in this behavior for emotional satisfaction, sexual arousal, or self-identification. Since their pleasure in wearing clothes of the opposite gender is not necessary linked with sexual orientation, transvestites may be heterosexual, homosexual or bisexual.

Transsexuals, or intersexuals, are individuals who identify with a physical sex different from the one with which they were born and raised. These individuals may have aspects of the male/female duality or they may have been assigned the wrong gender at birth. Transsexuals may choose to ignore these feelings, or they may choose to wear the clothing of and pass as the opposite gender. They may or may not choose to undergo gender reassignment through hormone therapy or surgery. Transsexuals and their advocates are somewhat divided over this last point, as some question the need for hormone therapy and surgery to change the gender of an individual, arguing that this process enhances traditional, distorted views of gender in our society rather than supports gender diversity. In terms of their sexual orientation, transgendered individuals who are attracted to women express gynephilia, while individuals attracted to men express androphilia.

Further Insights

Sexual orientation can be defined in many ways, but the most familiar definitions are also the legal definitions: heterosexuality, homosexuality and bisexuality. Heterosexuality is a sexual attraction to individuals of the opposite gender, while homosexuality is an attraction to individuals of the same gender. Bisexuality is an attraction to both men and women, although some individuals choose to use the words "polysexual" or "pansexual" to avoid bisexuality's implicit assumption that only two genders exist. Asexuality is a lack of sexual interest altogether. In 2013 a Gallup study estimated that the nationwide average of lesbian, gay, bisexual, and transgender individuals in the United States is between 3.5 and 4 percent; estimates in different states range from 1.7 percent (North Dakota) to 10 percent (District of Columbia).

Kauth described sexual orientation as "a biologically based processing bias continuously exploited or challenged by social and cultural conditions," taking into account both sides of the nature versus nurture debate on sexual orientation (2000; LeVay, 2008). Rather than identifying any one factor as a determinant of sexual orientation, such a definition takes in several factors: anatomical brain studies, functional brain studies, genetics/chromosomal, birth order, anatomical, cognitive, developmental, psychoanalytic theories, behaviorism/socialization, sexual experiences, social constructionism, sociocultural, and personal identity.

Anatomical Brain Studies

A number of studies on the anatomical aspects of sexual orientation have focused on the brain. One of the more well-known studies was conducted by LeVay, who argued that the hypothalamus, a part of the underside of the brain which controls hormone production and release, is different in gay and straight men (1991). However LeVay's critics have pointed out that since all of his research was conducted on the brains of individuals who died of AIDS, the results of his study may be invalid. More recently, Savic and Lindstrom suggested that when comparisons are made of left and right brain hemispheres, differences can be seen between heterosexual and homosexual individuals (2008). Similarly, Gorski reported that "the anterior commissure, a bundle of fibers running across the midline of the brain, is larger in women and gay men than heterosexual men" (1978; Odent & Odent, 2006, ¶10).

LeVay has suggested that these differences in brain anatomy may be caused by some prenatal factor (like hormone levels) that affects the fetus' development and, thus, the baby's sexual orientation (2003, 2008). This theory is called the early fixation hypothesis. While studies have failed to find a link between adult's hormone levels and sexual orientation, Dorner and others have argued that prenatal hormone levels may impact the sexual orientation of an individual in later life (1969). Although little empirical evidence is offered, it is the case that certain medical conditions (like congenital adrenal hyperplasia, in which high levels of testosterone-like hormones masculinize external genitalia in female fetuses) and drugs can impact a fetus' physiological gender characteristics. However, so far no research has proven that these conditions or drugs actually increase the person's likelihood of being homosexual (LeVay, 2003, 2008). In fact, research suggests that the majority of women affected by congenital adrenal hyperplasia identity as heterosexual, which would seem to disprove the theory that female fetal exposure to male hormones can cause lesbianism (Peplau, Spaulding, Conley, & Veniegas, 1999).

Functional Brain Studies

Preliminary studies of brain function have found minor differences between heterosexual and homosexual individuals in terms of startle response, sounds produced by the inner ear, sexual arousal and brain activity, neurotransmitter function, and odor response (LeVay, 2003, 2008).

Genetics/Chromosomal

In his studies of male homosexuals in Mormon populations that maintained excellent geologies, Hamer reported that individuals with a certain constellation of genetic material at the Xq28 gene loci on the X chromosome had a 70% likelihood of being gay (1993). If that composition was not present, individuals had a 100% likelihood of not being gay. Note that the gene loci was on the male's X chromosome, meaning that this genetic characteristic is carried in the mother's DNA. However, similar studies conducted on women failed to find any significance, and efforts to replicate Hamer's findings have been inconclusive (Hamer & Copeland, 1994; Hamer & Hu, 1993; LeVay 2008). Another researcher, Mustanski, reported finding evidence of linkage with sexual orientation at markers 8p12, 7q36, and 10q26, with the latter two being affected by equal parts of maternal and paternal genetic influences (LeVay, 2008).

In their review of the literature on genetic studies of twins, Bearman and Bruckner concluded that, while genetics may play a part in sexual orientation, its role is dwarfed by those of other factors, and sexual orientation is more likely socially constructed than biologically determined (2002). Other studies of twins have found that while monozygotic twins are more likely to have the same sexual orientation, this tendency does not prove that sexual orientation is primarily biological (Peplau, et. al., 1999; LeVay, 2008). Studies of siblings have found that lesbians do seem to report a greater number of siblings who also are gay, but, again, this correlation does not prove that genetics is the exclusive cause of homosexuality (Peplau, et. al., 1999).

Birth Order

Focusing on birth order as a causal factor, Blanchard and Klassen reported that gay men are more likely to be among the youngest of their siblings and to have more older brothers than heterosexual men (1997; LeVay, 2008). They argued that because mothers develop male-specific antibodies during each pregnancy with a male child and because the antigens involved in brain masculinization gradually grow weaker with each pregnancy, subsequent male children are more likely homosexually oriented.

Anatomical

Several studies have concluded that lesbian women's index fingers are shorter than their ring finger, whereas most women's ring and index fingers are about the same length (LeVay, 2008). Another study found a difference in fingerprint patterns between straight and gay men, but these findings have not been replicated (LeVay, 2008).

Cognitive

Other researchers have focused on finding differences in how heterosexual and homosexual individuals acquire knowledge through reasoning, intuition and perception. LeVay provided a detailed review of their findings in areas such as:

• Visuospatial tasks (straight men were slightly more able than gay men),
• Object location memory (gay men did better than straight men, and lesbian and straight women were equal),
• Verbal fluency (mixed results, but slight advantage to gay men and lesbians),
• Aggressiveness (gay men were less aggressive than straight men, and lesbian and straight women were equal), and
• Handedness (homosexuals were more likely to be left-handed than their heterosexual counterparts) (LeVay, 2008).

However, these findings are not consistent overall.

Developmental

Daryl Bem, a psychologist from Cornell University, has become known for his argument that children's biologically determined temperaments can cause some to be attracted to activities that are associated with a gender role other than the one that corresponds to their physical sex. Thus, a temperamentally nurturing boy may prefer to play with dolls, or a temperamentally aggressive girl may prefer to play football. Bem argued that because of these temperamental and activity differences, these children will grow up feeling different from their own gender groups and eventually eroticize these differences, leading to same-sex attraction. Bem's theory is based upon numerous studies which suggest that gay males, in particular, report not conforming to gender roles during childhood. However, much of Bem's theoretical framework is based upon an analysis of male behavior, so it may not be applicable to female sexual orientation development (Swidey, 2005).

One interesting related argument put forth by Bem is that sexual orientation need not be based upon gender (Bem, 1996). Attachment theories of sexual orientation development hold that individuals feel sexual arousal toward others and then develop attachment bonds that define their sexual orientation (Zeifman & Hazan, 1997). In other words, a male would feel sexual arousal toward women and then develop attachment bonds that lead to heterosexuality. However, this theory would seem to be contrary to the experience of many lesbian women, who report the opposite experience of forming a strong emotional attachment to another woman that then develops into a sexual relationship (Peplau, et. al., 1999).

Psychoanalytic Theories

Inversion theory is based upon Freudian psychosexual developmental analysis. Under this theory, boys are thought to become homosexual if they have a close relationship with a dominant mother while their father is distant or absent. Girls, on the other hand, become lesbian because they have a strong, unconscious dislike of their mothers or because of penis envy (LeVay, 2008). However, analyst Richard Isay has argued that a same-gender parent's negative behavior toward their pre-gay child may be a response to the child's atypical gender characteristics rather than the cause of them (1996, 1989).

Though not many scholars uphold inversion theory today, it is still important since it has guided biological studies of homosexuality with its assumptions that gay men are physically and emotionally effeminate and lesbians physically and emotionally masculine. Much of the traditional literature on sexual orientation builds upon this premise, seeking affirmation of the view that atypical gender characteristics explain sexual orientation. Over the decades, dozens of studies have compared the masculine and feminine qualities of lesbians and heterosexual women, and a good number have concluded that lesbians score higher on masculine traits such as straightforwardness, sense of honor, direct speech, and voice inflexions (Peplua, 1999). However, others have shown that when study participants are matched upon socioeconomic factors, educational level, and feminist beliefs, the differences between lesbians and heterosexual women are nonexistent.

Behaviorism/Socialization

Behaviorist and socialization theories suggest that gender and sexual orientation are learned behaviors which are consciously and unconsciously inculcated by parents, peers, and society at large. However, critics of these theories argue that while gender identity and roles, sexual orientation, sexual attitudes and beliefs, and sexual knowledge are influenced by cultural attitudes and values, alone they cannot account for homosexuality, since most homosexual individuals are raised by heterosexual role models. Similarly, studies have shown that homosexual parents are no more likely to socialize their child to be homosexual than are heterosexual parents.

Sexual Experiences

Some individuals argue that early sexual experiences can influence one's sexual orientation. A young woman, who has been raped, for example, may be averse to sex with men and become lesbian. Similarly, a young boy who sexually experiments with other boys may come to define himself as homosexual. However, critics charge that this explanation fails to describe most people's sexual experimentation and development. Most scholars believe that this theory is not credible.

Social Constructionism

Others follow Foucault in claiming that gender, gender roles, and sexual orientation are labels, which society imposes upon the individual and which the individual internalizes (1978). As such, sexual orientation labels do not arise from within the individual, but are adopted by him or her (LeVay, 2008).

Sociocultural

In her cross-cultural review of women's sexuality, Blackwood suggested that cultures vary significantly in the extent to which they regulate women's lives, sexuality, and reproduction (1986). For instance, marriage, whether arranged or freely chosen, is often the expected outcome for women in most cultures. Some cultures, however, are accepting of sexual relationships between women who are married to men, as long as they are inconspicuous and informal (Peplua, 1999). Khan, for example, reported that in modern Pakistan, if a woman refuses to marry she is a "pariah," but if she marries and engages in sexual relationships with women, these relationships are overlooked as long as she fulfills her marital and familial obligations (1997).

Personal Identity

Despite whatever role the developmental or physiological processes play in sexual orientation, more and more scholars are emphasizing that it is the individual's self-knowledge, self-acceptance, and identity that ultimately defines his or her sexual orientation. Their research has led them to observe that some individuals may identify with different sexual orientations at various times in their lives, while others may adhere to a heterosexual identity, though they may have had numerous homosexual encounters. For instance, in his study of the "tearoom trade" (sex between men in public restrooms) Humphrey's found that a majority of his study's participants were married and did not define themselves as homosexual (Humphreys, 1970). Some would argue that such men are closeted gay men, but an increasing number of scholars would accept the study participants' heterosexual self-definition by separating personal identity from sexual behavior.

Conclusion

Can sexual orientation be changed? Although several "therapeutic" techniques have been applied to alter sexual orientation, there is no evidence that this reparative or conversion therapy works. In fact, the American Psychiatric Association suggests that reparative therapy has numerous risks, including depression, anxiety, and self-destructive behavior. Aversion therapy, for example, may teach one to curb homosexual behaviors, but behavior is only one aspect of an individual's sexual orientation. Those who undergo this sort of therapy may continue to have same-gender feelings of attraction and arousal. These types of therapies generally stem from the belief that homosexuality is a disorder. While this belief remains intact in some socially conservative segments of society, there is a growing professional and public awareness that sexual orientation and gender orientation are multifaceted and complex expressions of human life.

Terms & Concepts

Androphilia: Having a sexual attraction to males.

Bisexual: Having a sexual attraction to both males and females.

Gonad: An organ that produces reproductive cells, or gametes. In males, these organs are the testes; in females, they are the ovaries.

Gynephilia: Having a sexual attraction to females.

Heterosexual: Having a sexual attraction to members of the opposite sex.

Homosexual: Having a sexual attraction to members of one's own sex.

Monozygotic Twins: Twins who developed from a single egg (also called identical twins).

Neurology: The study of the nervous system.

Polysexual: Having a sexual attraction to both males and females. Some individuals prefer to use this term rather than "bisexual" because they do not believe that there are only two genders.

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Suggested Reading

Balen, A., Creighton, S., Davies, M., MacDougall, J., & Stanhope, R. (Eds.). (2004). Paediatric and adolescent gynaecology: A multidisciplinary approach. Cambridge, UK: Cambridge University Press.

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Dreger, A. D. (1998). Hermaphrodites and the medical invention of sex. Cambridge, MA: Harvard University Press.

Fjelstrom, J. (2013). Sexual orientation change efforts and the search for authenticity. Journal Of Homosexuality, 60, 801–827. Retrieved November 4, 2013 from EBSCO Online Database SocINDEX with Full Text. http://search.ebscohost.com/login.aspx?direct=true&db=sih&AN=87672396

Harbeck, K. M. (Ed.). (1991). Coming out of the classroom closet: Gay and lesbian students, teachers, and curricula. New York: Haworth.

Harbeck, K. M. (1997). Gay and lesbian educators: Personal freedoms/Public constraints. Malden, MA: Amethyst Press.

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