Sexual orientation describes a pattern of emotional, romantic, or sexual attractions to the opposite sex, the same sex, both, or neither, and the
genderGender is a range of characteristics used to distinguish between males and females, particularly in the cases of men and women and the masculine and feminine attributes assigned to them. Depending on the context, the discriminating characteristics vary from sex to social role to gender identity...
s that accompany them. By the convention of organized researchers, these attractions are subsumed under
heterosexualityHeterosexuality is romantic or sexual attraction or behavior between members of the opposite sex or gender. As a sexual orientation, heterosexuality refers to "an enduring pattern of or disposition to experience sexual, affectional, physical or romantic attractions to persons of the opposite sex";...
,
homosexualityHomosexuality is romantic or sexual attraction or behavior between members of the same sex or gender. As a sexual orientation, homosexuality refers to "an enduring pattern of or disposition to experience sexual, affectional, or romantic attractions" primarily or exclusively to people of the same...
,
bisexualityBisexuality is sexual behavior or an orientation involving physical or romantic attraction to both males and females, especially with regard to men and women. It is one of the three main classifications of sexual orientation, along with a heterosexual and a homosexual orientation, all a part of the...
, and
asexualityAsexuality , in its broadest sense, is the lack of sexual attraction and, in some cases, the lack of interest in sex. Sometimes, it is considered a lack of a sexual orientation...
. According to the
American Psychological AssociationThe American Psychological Association is the largest scientific and professional organization of psychologists in the United States. It is the world's largest association of psychologists with around 154,000 members including scientists, educators, clinicians, consultants and students. The APA...
, sexual orientation is enduring and also refers to a person's sense of "personal and
social identityA social identity is the portion of an individual's self-concept derived from perceived membership in a relevant social group. As originally formulated by Henri Tajfel and John Turner in the 1970s and 80s, social identity theory introduced the concept of a social identity as a way in which to...
based on those attractions, behaviors expressing them, and membership in a community of others who share them." The term
sexual preference largely overlaps with sexual orientation, but is distinguished in psychological research. A person who identifies as bisexual, for example, may sexually prefer one sex over the other. "Sexual preference" may also suggest a degree of voluntary choice, which is disputed in terms of sexual formation.
The current consensus among scholars is that sexual orientation is not a choice. No simple, single cause for sexual orientation has been conclusively demonstrated, but research suggests that it is by a
combination of genetic, hormonal, and environmental influencesBiology and sexual orientation is the subject of research into the role of biology in the development of human sexual orientation. No simple, single cause for sexual orientation has been conclusively demonstrated, but research suggests that it is by a combination of genetic, hormonal, and...
, with biological factors involving a complex interplay of genetic factors and the early uterine environment. Research over several decades has demonstrated that sexual orientation ranges along
a continuumThe concept of the heterosexual–homosexual continuum is a psychological and philosophical understanding of human sexuality that places sexual orientation on a continuum from heterosexuality to homosexuality...
, from exclusive attraction to the opposite sex to exclusive attraction to the same sex. It is usually discussed in terms of heterosexuality, bisexuality and homosexuality, though asexuality is increasingly recognized as a fourth category. These categories are aspects of the more nuanced nature of sexual identity. For example, people may use other labels or none at all.
While sexual orientation is reported in this article primarily within
biologyBiology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
and
psychologyPsychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...
, including
sexologySexology is the scientific study of human sexuality, including human sexual interests, behavior, and function. The term does not generally refer to the non-scientific study of sex, such as political analysis or social criticism....
, for reports within
anthropologyAnthropology is the study of humanity. It has origins in the humanities, the natural sciences, and the social sciences. The term "anthropology" is from the Greek anthrōpos , "man", understood to mean mankind or humanity, and -logia , "discourse" or "study", and was first used in 1501 by German...
and
historyHistory is the discovery, collection, organization, and presentation of information about past events. History can also mean the period of time after writing was invented. Scholars who write about history are called historians...
, including social constructionism, see the section on other explanations.
Sexual orientation distinguished from sexual identity and behavior
Most definitions of sexual orientation include a psychological component, such as the direction of an individual's erotic desire, or a behavioral component, which focuses on the sex of the individual's sexual partner/s. Some people prefer simply to follow an individual's self-definition or
identityIdentity is a term used to describe a person's conception and expression of their individuality or group affiliations . The term is used more specifically in psychology and sociology, and is given a great deal of attention in social psychology...
.
The
American Psychological AssociationThe American Psychological Association is the largest scientific and professional organization of psychologists in the United States. It is the world's largest association of psychologists with around 154,000 members including scientists, educators, clinicians, consultants and students. The APA...
states that "[s]exual orientation is an enduring emotional, romantic, sexual, or affectional attraction toward others. It is easily distinguished from other components of sexuality including biological sex, gender identity (the psychological sense of being male or female), and the social gender role (adherence to cultural norms for feminine and masculine behavior). Sexual orientation exists along a continuum that ranges from exclusive heterosexuality to exclusive homosexuality and includes various forms of bisexuality. Bisexual persons can experience sexual, emotional, and affectional attraction to both their own sex and the opposite sex. Persons with a homosexual orientation are sometimes referred to as gay (both men and women) or as lesbian (women only). Sexual orientation is different from sexual behavior because it refers to feelings and self-concept. Individuals may or may not express their sexual orientation in their behaviors."
Sexual identitySexual orientation identity describes how persons identify their own sexuality. In addition, they may choose not to identify their sexual orientation, or dis-identify with a sexual orientation.This may or may not relate to their actual sexual orientation...
and sexual behavior are closely related to sexual orientation, but they are distinguished, with identity referring to an individual's conception of themselves, behavior referring to actual sexual acts performed by the individual, and orientation referring to "fantasies, attachments and longings." Individuals may or may not express their sexual orientation in their behaviors. People who have a homosexual sexual orientation that does not align with their sexual identity are sometimes referred to as '
closetedCloseted and in the closet are metaphors used to describe lesbian, gay, bisexual, transgender, queer/questioning and intersex people who have not disclosed their sexual orientation or gender identity and aspects thereof, including sexual identity and sexual behavior.-Background:In late 20th...
'. The term may, however, reflect a certain cultural context and particular stage of transition in societies which are gradually dealing with integrating sexual minorities. In studies related to sexual orientation, when dealing with the degree to which a person's
sexual attractionSexual attractiveness or sex appeal refers to an individual's ability to attract the sexual or erotic interest of another person, and is a factor in sexual selection or mate choice. The attraction can be to the physical or other qualities or traits of a person, or to such qualities in the context...
s, behaviors and identity match, scientists usually use the terms
concordance or
discordance. Thus, a woman who is attracted to other women, but calls herself heterosexual and only has sexual relations with men, can be said to experience discordance between her sexual orientation (homosexual or lesbian) and her sexual identity and behaviors (heterosexual).
Sexual identity may also be used to describe a person's perception of his or her own
sex, rather than sexual orientation. The term
sexual preference has a similar meaning to
sexual orientation, but it may be incorrectly interpreted as endorsing the notion that sexual orientation is, in whole or part, a matter of choice.
Sexualities included
Sexual orientation traditionally was defined as including
heterosexualityHeterosexuality is romantic or sexual attraction or behavior between members of the opposite sex or gender. As a sexual orientation, heterosexuality refers to "an enduring pattern of or disposition to experience sexual, affectional, physical or romantic attractions to persons of the opposite sex";...
,
bisexualityBisexuality is sexual behavior or an orientation involving physical or romantic attraction to both males and females, especially with regard to men and women. It is one of the three main classifications of sexual orientation, along with a heterosexual and a homosexual orientation, all a part of the...
, and homosexuality.
AsexualityAsexuality , in its broadest sense, is the lack of sexual attraction and, in some cases, the lack of interest in sex. Sometimes, it is considered a lack of a sexual orientation...
is now considered a sexual orientation by some researchers and has been defined as the absence of a traditional sexual orientation. An asexual has little to no sexual attraction to males or females.
Androphilia and gynephilia
Androphilia and
gynephilia (or
gynecophilia) are terms used in behavioral science to describe sexual attraction, as an alternative to a homosexual and heterosexual conceptualization. They are used for identifying a subject's object of attraction without attributing a
sex assignmentSex assignment refers to the assigning of the biological sex at the birth of a baby. In the majority of births, a relative, midwife, or physician inspects the genitalia when the baby is delivered, sees ordinary male or female genitalia, and declares, "it's a girl" or "it's a boy" without the...
or
gender identityA gender identity is the way in which an individual self-identifies with a gender category, for example, as being either a man or a woman, or in some cases being neither, which can be distinct from biological sex. Basic gender identity is usually formed by age three and is extremely difficult to...
to the subject. Related terms like
bisexual and
pansexual do not make any assignations to the subject. Using
androphilia and
gynephilia can avoid confusion and offense when describing people in non-western cultures, as well as when describing
intersexIntersex, in humans and other animals, is the presence of intermediate or atypical combinations of physical features that usually distinguish female from male...
and
transgenderTransgender is a general term applied to a variety of individuals, behaviors, and groups involving tendencies to vary from culturally conventional gender roles....
people.
Psychiatrist
Anil AggrawalAnil Aggrawal M.D. is a professor of forensic medicine at the Maulana Azad Medical College, New Delhi, India. He is known chiefly as the Editor-in-Chief of the Internet Journal of Forensic Medicine and Toxicology.-Early life:Dr...
explains that androphilia, along with gynephilia, "is needed to overcome immense difficulties in characterizing the sexual orientation of transmen and transwomen. For instance, it is difficult to decide whether a transman erotically attracted to males is a heterosexual female or a homosexual male; or a transwoman erotically attracted to females is a heterosexual male or a lesbian female. Any attempt to classify them may not only cause confusion but arouse offense among the affected subjects. In such cases, while defining sexual attraction, it is best to focus on the object of their attraction rather than on the sex or gender of the subject." Sexologist
Milton DiamondMilton Diamond is a retired professor of anatomy and reproductive biology at the University of Hawai'i at Mānoa. He has had a very long and productive career in the study of human sexuality...
writes, "The terms heterosexual, homosexual, and bisexual are better used as adjectives, not nouns, and are better applied to behaviors, not people. This usage is particularly advantageous when discussing the partners of transsexual or intersexed individuals. These newer terms also do not carry the social weight of the former ones."
Some researchers advocate use of the terminology to avoid
biasBias is an inclination to present or hold a partial perspective at the expense of alternatives. Bias can come in many forms.-In judgement and decision making:...
inherent in
WesternWestern culture, sometimes equated with Western civilization or European civilization, refers to cultures of European origin and is used very broadly to refer to a heritage of social norms, ethical values, traditional customs, religious beliefs, political systems, and specific artifacts and...
conceptualizations of human sexuality. Writing about the
SamoanSamoan may refer to:* a native of, or relating to, the Samoan Islands in the South Pacific Ocean** the Samoan language, the native language of the Samoan Islands** a member of the Samoans, a Polynesian ethnic group of the Samoan Islands...
fa'afafineFa'afafine may be viewed as a third gender specific to Samoan culture.Fa'afafine are biological males who have a strong feminine gender orientation, which the Samoan parents recognize quite early in childhood. Not always are they raised as female children or rather 'third gender' children...
demographic, sociologist Johanna Schmidt writes that in cultures where a
third genderThe terms third gender and third sex describe individuals who are categorized as neither man nor woman, as well as the social category present in those societies who recognize three or more genders...
is recognized, a term like "homosexual transsexual" does not align with cultural categories.
Other researchers, such as
Bruce BagemihlBruce Bagemihl is a Canadian biologist, linguist, and author of the book Biological Exuberance: Animal Homosexuality and Natural Diversity.-Life and career:He served on the faculty of University of British Columbia, and he earned a Ph.D...
, have criticized the labels "androphilia" and "gynephilia/gynecophilia" as confusing and degrading. Bagemihl writes, "...the point of reference for 'heterosexual' or 'homosexual' orientation in this nomenclature is solely the individual's genetic sex prior to reassignment (see for example, Blanchard et al. 1987[24], Coleman and Bockting, 1988[25], Blanchard, 1989[26]). These labels thereby ignore the individual’s personal sense of gender identity taking precedence over biological sex, rather than the other way around." Bagemihl goes on to take issue with the way this terminology makes it easy to claim transsexuals are really homosexual males seeking to escape from stigma.
Gender, transgender, cisgender, and conformance
The earliest writers on sexual orientation usually understood it to be intrinsically linked to the subject's own sex. For example, it was thought that a typical female-bodied person who is attracted to female-bodied persons would have masculine attributes, and vice versa. This understanding was shared by most of the significant theorists of sexual orientation from the mid nineteenth to early twentieth century, such as
Karl Heinrich Ulrichsfor the periodical directory, see Ulrich's Periodicals DirectoryKarl-Heinrich Ulrichs , is seen today as the pioneer of the modern gay rights movement.-Early life:...
, Richard von Krafft-Ebing,
Magnus HirschfeldMagnus Hirschfeld was a German physician and sexologist. An outspoken advocate for sexual minorities, Hirschfeld founded the Scientific Humanitarian Committee, which Dustin Goltz called "the first advocacy for homosexual and transgender rights."-Early life:Hirschfeld was born in Kolberg in a...
,
Havelock EllisHenry Havelock Ellis, known as Havelock Ellis , was a British physician and psychologist, writer, and social reformer who studied human sexuality. He was co-author of the first medical textbook in English on homosexuality in 1897, and also published works on a variety of sexual practices and...
,
Carl JungCarl Gustav Jung was a Swiss psychiatrist and the founder of Analytical Psychology. Jung is considered the first modern psychiatrist to view the human psyche as "by nature religious" and make it the focus of exploration. Jung is one of the best known researchers in the field of dream analysis and...
, and
Sigmund FreudSigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
, as well as many gender-variant homosexual people themselves. However, this understanding of homosexuality as sexual inversion was disputed at the time, and, through the second half of the twentieth century,
gender identityA gender identity is the way in which an individual self-identifies with a gender category, for example, as being either a man or a woman, or in some cases being neither, which can be distinct from biological sex. Basic gender identity is usually formed by age three and is extremely difficult to...
came to be increasingly seen as a phenomenon distinct from sexual orientation.
TransgenderTransgender is a general term applied to a variety of individuals, behaviors, and groups involving tendencies to vary from culturally conventional gender roles....
and
cisgenderCisgender is an adjective used in the context of gender issues and counselling to refer to a class of gender identities formed by a match between an individual's gender identity and the behavior or role considered appropriate for one's sex.Kristen Schilt and Laurel Westbrook defined "cisgender"...
people may be attracted to men, women, or both, although the prevalence of different sexual orientations is quite different in these two populations (see sexual orientation of transwomen). An individual homosexual, heterosexual or bisexual person may be masculine, feminine, or
androgynousAndrogyny is a term derived from the Greek words ανήρ, stem ανδρ- and γυνή , referring to the combination of masculine and feminine characteristics...
, and in addition, many members and supporters of lesbian and gay communities now see the "gender-conforming heterosexual" and the "gender-nonconforming homosexual" as negative
stereotypeA stereotype is a popular belief about specific social groups or types of individuals. The concepts of "stereotype" and "prejudice" are often confused with many other different meanings...
s. However, studies by
J. Michael BaileyJohn Michael Bailey is an American psychologist and professor at Northwestern University. He is best known among scientists for his work on the etiology of sexual orientation, from which he concluded that homosexuality is substantially inherited...
and KJ Zucker have found that a majority of gay men and lesbians report being gender-nonconforming during their childhood years.
The majority of transgender people today identify with the sexual orientation that corresponds with their gender; meaning that a transwoman who is solely attracted to women would often identify as a lesbian. Female-attracted
transmenA trans man, transman, trans guy, or FTM is a transgender or transsexual man: a person who was assigned female at birth, but who identifies as male....
often consider themselves straight men, yet some participate in the lesbian community.
Sexual orientation sees greater intricacy when non-binary understandings of both sex (male, female, or
intersexIntersex, in humans and other animals, is the presence of intermediate or atypical combinations of physical features that usually distinguish female from male...
) and gender (man, woman,
transgenderTransgender is a general term applied to a variety of individuals, behaviors, and groups involving tendencies to vary from culturally conventional gender roles....
,
third genderThe terms third gender and third sex describe individuals who are categorized as neither man nor woman, as well as the social category present in those societies who recognize three or more genders...
, or
gender variantGender variance, or gender nonconformity, is behaviour or gender expression that does not conform to dominant gender norms of male and female...
) are considered. Sociologist
Paula Rodriguez RustPaula Claire Rodriguez Rust is an American sociologist who studies sexual orientation, especially bisexuality. Rust is author of Bisexuality in the United States and Bisexuality and the Challenge to Lesbian Politics: Sex, Loyalty, and Revolution.-Life and career:Rust earned a Ph.D. in Sociology...
(2000) argues for a more multifaceted definition of sexual orientation:
Relationships outside of orientation
Gay and lesbian people can have sexual relationships with someone of the opposite sex for a variety of reasons, including the desire for family with children and concerns of discrimination and religious
ostracism.
While some
GLBTLGBT is an initialism that collectively refers to "lesbian, gay, bisexual, and transgender" people. In use since the 1990s, the term "LGBT" is an adaptation of the initialism "LGB", which itself started replacing the phrase "gay community" beginning in the mid-to-late 1980s, which many within the...
people hide their respective orientations from their spouses, others develop positive gay and lesbian identities while maintaining successful marriages.
Coming outComing out is a figure of speech for lesbian, gay, bisexual, and transgender people's disclosure of their sexual orientation and/or gender identity....
of the closet to oneself, a spouse of the opposite sex, and children can present challenges that are not faced by gay and lesbian people who are not married to people of the opposite sex or do not have children.
Fluidity of sexuality
The
American Psychiatric AssociationThe American Psychiatric Association is the main professional organization of psychiatrists and trainee psychiatrists in the United States, and the most influential worldwide. Its some 38,000 members are mainly American but some are international...
(APA) has stated, "some people believe that sexual orientation is innate and fixed; however, sexual orientation develops across a person's lifetime". The APA also says that "most people experience little or no sense of choice about their sexual orientation". "
[F
]or some
["people"
] the focus of sexual interest will shift at various points through the life span..." A community may change over time. In a joint statement with other major American medical, psychology, educator, and religious organizations, the APA says that "different people realize at different points in their lives that they are heterosexual, gay, lesbian, or bisexual". A report from the
Centre for Addiction and Mental HealthThe Centre for Addiction and Mental Health is a consortium of mental health clinics at several sites in Toronto, Ontario, Canada. Its name in French is Centre de toxicomanie et de santé mentale...
states, "For some people, sexual orientation is continuous and fixed throughout their lives. For others, sexual orientation may be fluid and change over time". "There . . .
[was, as of 1995,
] essentially no research on the longitudinal stability of sexual orientation over the adult life span. . . .
[I
]t
[was
] . . . still an unanswered question whether . . .
[the
] measure
[of "the complex components of sexual orientation as differentiated from other aspects of sexual identity at one point in time"
] will predict future behavior or orientation. Certainly, it
[was
] . . . not a good predictor of past behavior and self-identity, given the developmental process common to most gay men and lesbians (i.e., denial of homosexual interests and heterosexual experimentation prior to the coming-out process)."
"
[A number of
] lesbian women, and some heterosexual women as well, perceive choice as an important element in their sexual orientations."
Born bisexual, then monosexualizing
Innate bisexualityInnate bisexuality is a term introduced by Sigmund Freud , that expounds all humans are born bisexual but through psychological development become monosexual while the bisexuality remains in a latent state.There is no modern scientific consensus as to...
, or predisposition to bisexuality, is an idea introduced by
Sigmund FreudSigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
, based on work by his associate
Wilhelm FliessWilhelm Fliess was a German Jewish otolaryngologist who practised in Berlin. On Josef Breuer's suggestion, Fliess attended several "conferences" with Sigmund Freud beginning in 1887 in Vienna, and the two soon formed a strong friendship...
. According to this theory, all humans are born bisexual but through psychological development, which includes both external and internal factors, become monosexual while the bisexuality remains in a latent state.
Efforts to change sexuality
No major mental health professional organization has sanctioned efforts to change sexual orientation and virtually all of them have adopted policy statements cautioning the profession and the public about treatments that purport to change sexual orientation. These include the American Psychiatric Association, American Psychological Association, American Counseling Association, National Association of Social Workers in the USA, the Royal College of Psychiatrists, and the Australian Psychological Society. According to the American Psychological Association and the Royal College of Psychiatrists' Gay and Lesbian Mental Health Special Interest Group, there is no sound scientific evidence that sexual orientation can be changed.
In 2009 the American Psychological Association Task Force on Appropriate Therapeutic Responses to Sexual Orientation conducted a systematic review of the peer-reviewed journal literature on sexual orientation change efforts (SOCE) and concluded:
Efforts to change sexual orientation are unlikely to be successful and involve some risk of harm, contrary to the claims of SOCE practitioners and advocates. Even though the research and clinical literature demonstrate that same-sex sexual and romantic attractions, feelings, and behaviors are normal and positive variations of human sexuality, regardless of sexual orientation identity, the task force concluded that the population that undergoes SOCE tends to have strongly conservative religious views that lead them to seek to change their sexual orientation. Thus, the appropriate application of affirmative therapeutic interventions for those who seek SOCE involves therapist acceptance, support, and understanding of clients and the facilitation of clients' active coping, social support, and identity exploration and development, without imposing a specific sexual orientation identity outcome.
NARTH, which describes itself as a "professional, scientific organization that offers hope to those who struggle with unwanted homosexuality," disagrees with the mainstream mental health community's position on conversion therapy. The American Psychological Association and the Royal College of Psychiatrists expressed concerns that the positions espoused by NARTH are not supported by the science and create an environment in which prejudice and discrimination can flourish.
Measuring sexual orientation
Varying definitions and strong
social norms about sexualityA sexual norm can refer to a personal or a social norm. Most cultures have social norms regarding sexuality, and define normal sexuality to consist only of certain legal sex acts between individuals who meet specific criteria of age, consanguinity , race/ethnicity A sexual norm can refer to a...
can make sexual orientation difficult to quantify.
Scales for assessments
From at least the late nineteenth century in Europe, there was speculation that the range of human sexual response looked more like a continuum than two or three discrete categories. Berlin sexologist
Magnus HirschfeldMagnus Hirschfeld was a German physician and sexologist. An outspoken advocate for sexual minorities, Hirschfeld founded the Scientific Humanitarian Committee, which Dustin Goltz called "the first advocacy for homosexual and transgender rights."-Early life:Hirschfeld was born in Kolberg in a...
published a scheme in 1896 that measured the strength of an individual's sexual desire on two independent 10-point scales, A (homosexual) and B (heterosexual). A heterosexual individual may be A0, B5; a homosexual individual may be A5, B0; an asexual would be A0, B0; and someone with an intense attraction to both sexes would be A9, B9.
Fifty years later, American sexologist
Alfred KinseyAlfred Charles Kinsey was an American biologist and professor of entomology and zoology, who in 1947 founded the Institute for Sex Research at Indiana University, now known as the Kinsey Institute for Research in Sex, Gender, and Reproduction, as well as producing the Kinsey Reports and the Kinsey...
wrote in
Sexual Behavior in the Human Male (1948):
The
Kinsey scaleThe Kinsey scale, also called the Heterosexual-Homosexual Rating Scale, attempts to describe a person's sexual history or episodes of his or her sexual activity at a given time. It uses a scale from 0, meaning exclusively heterosexual, to 6, meaning exclusively homosexual...
measures sexual orientation from 0 (exclusively heterosexual) to 6 (exclusively homosexual), with an additional category, X, for those with no sexual attraction to either women or men. Unlike Hirschfeld's scale, the Kinsey scale is one-dimensional.
Simon LeVaySimon LeVay is a British-American neuroscientist. He is known for his studies about brain structures and sexual orientation.-Personal life:LeVay was born on August 28, 1943 in Oxford, England...
wrote, "it suggests (although Kinsey did not actually believe this) that every person has the same fixed endowment of sexual energy, which he or she then divides up between same-sex and opposite-sex attraction in a ratio indicative of his or her own sexual orientation."
Means of assessment
Means typically used include surveys, interviews, cross-cultural studies, physical arousal measurements sexual behavior, sexual fantasy, or a pattern of erotic arousal. The most common is verbal self-reporting or self-labeling, which depend on respondents being accurate about themselves.
Biology
Research has identified several biological factors which may be related to the development of sexual orientation, including
geneA gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s,
prenatal hormonesThe hormonal theory of sexuality holds that, just as exposure to certain hormones plays a role in fetal sex differentiation, such exposure also influences the sexual orientation that emerges later in the adult...
, and
brainThe human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
structure. No single controlling cause has been identified, and research is continuing in this area.
The prevailing view is that sexual orientation is biological in nature, determined by a complex interplay of genetic factors and the early uterine environment. Sexual orientation is therefore not a choice. That is, individuals do not choose to be homosexual, heterosexual, bisexual, or asexual. There is no substantive evidence to support the suggestion that early childhood experiences, parenting, sexual abuse, or other adverse life events influence sexual orientation. However, studies do find that as aspects of sexuality expression have an experiential basis, parental attitudes towards a particular sexual orientation may affect how their children experiment with behaviours related to a certain orientation.
Homosexuality was once thought to be the result of troubled family dynamics or faulty psychological development. Those assumptions are now understood to have been based on misinformation and prejudice . Current scientific investigation seeks to find biological explanations for the adoption of a particular sexual orientation. As yet there are no replicated scientific studies supporting any specific biological etiology for human sexual orientation. although scientific studies have found a number of statistical biological differences between gay people and heterosexuals, which may result from the same underlying cause as sexual orientation itself.
Genetic factors
GeneA gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s may be related to the development of sexual orientation. There have been many studies conducted in order to search for a "gay gene". In Dean Hamer's study, his team found that 33 of the 40 pairs of gay brothers that were studied, had the same distinctive marker near the end of their X chromosome. However, he cautioned that a gene like this would unlikely be the cause of homosexuality. At one time, studies of twins appeared to point to a major genetic component, but problems in experimental design of the available studies have made their interpretation difficult, and one recent study appears to exclude genes as a major factor.
Hormones
The hormonal theory of sexuality holds that, just as exposure to certain
hormonesBiology and sexual orientation is the subject of research into the role of biology in the development of human sexual orientation. No simple, single cause for sexual orientation has been conclusively demonstrated, but research suggests that it is by a combination of genetic, hormonal, and...
plays a role in fetal sex differentiation, such exposure also influences the sexual orientation that emerges later in the adult.
Fetal hormones may be seen as either the primary influence upon adult sexual orientation or as a co-factor interacting with genes or environmental and social conditions.
A 2010 endocrinology study by Garcia-Falgueras and Swaab states that intrauterine exposure to hormones is largely the determinative criteria.
The auditory system
Sexual orientation depends on the ability of one person to identify the sex of another. In humans, this is a learned mental process. In 2008, it was suggested that innate root cues and mechanisms determine the sexual orientation of the adult.
These root cues and mechanisms process information that the child receives from the environment. They identify other sexual orientation cues that are embedded in the information flow, and internalize them in information structures. At
pubertyPuberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
, sexual orientation emerges. Adults of the same sexual orientation share common root cues and mechanisms. Different root cues and mechanisms result in different orientations. Different life experiences cause personal variations within an orientation.
The innate cues satisfy universality conditions: they do not depend on race, ethnicity, culture, or historical period. Root cues that are transmitted by men are different from those transmitted by women. The brains of boys and girls process those cues using the same innate mechanisms. Boys and girls whose innate brains are tuned to root cues transmitted by men will be sexually attracted, at puberty, to men. Boys and girls whose innate brains are tuned to women’s root cues will be sexually attracted, at puberty, to women. The emerging sexual orientation at
pubertyPuberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
depends on that actual innate tuning of the boy or the girl. That innate tuning may be
geneticGenetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
or due to sex hormones concentration in early developmental stages.
In humans, hearing is the only sense that satisfies the universality conditions. Both the vocal and
auditory systemThe auditory system is the sensory system for the sense of hearing.- Outer ear :The folds of cartilage surrounding the ear canal are called the pinna...
s are genetically differentiated between the sexes. Voice is one of the most robust, reliable, universal cues which are used for identifying the sex of a person. In addition, the auditory system shows differentiation along sex and orientation lines.
Currently, most of our knowledge about the underlying causes of sexual orientations is in the form of correlations between physiological features and sexual orientation. The auditory system provides not only correlations, but also feasible explanations of cause-effect relationships between system and mechanisms on one hand, and observed behaviors on the other. More studies are needed, though, to resolve the issue.
Sexual arousal
Studying human
sexual arousalSexual arousal, or sexual excitement, is the arousal of sexual desire, during or in anticipation of sexual activity. Things that precipitate human sexual arousal are called erotic stimuli, or colloquially known as turn-ons. There are many potential stimuli, both physical or mental, which can cause...
has proved a fruitful way of understanding how men and women differ as genders and in terms of sexual orientation. A clinical measurement may use
penilePenile plethysmography , or "phallometry", refers to measurement of bloodflow to the male genital. The most commonly reported methods of conducting penile plethysmography involve the measurement of the circumference of the penis with a mercury-in-rubber strain gauge, or the volume of the penis with...
or
vaginal photoplethysmographThe Vaginal photoplethysmograph is a type of plethysmograph. It consists of a clear acrylic, rod-shaped device that contains a light source, and a light detector. The light source illuminates the capillary bed of the vaginal wall and the blood circulating within it...
y, where genital engorgement with blood is measured in response to exposure to different erotic material.
Some researchers who study sexual orientation argue that the concept may not apply similarly to men and women. A study of
sexual arousalSexual arousal, or sexual excitement, is the arousal of sexual desire, during or in anticipation of sexual activity. Things that precipitate human sexual arousal are called erotic stimuli, or colloquially known as turn-ons. There are many potential stimuli, both physical or mental, which can cause...
patterns found that women, when viewing erotic films which show female-female, male-male and male-female sexual activity (oral sex or penetration), have patterns of arousal which do not match their declared sexual orientations as well as men's. That is, heterosexual and lesbian women's sexual arousal to erotic films do not differ significantly by the genders of the participants (male or female) or by the type of sexual activity (heterosexual or homosexual). On the contrary, men's sexual arousal patterns tend to be more in line with their stated orientations, with heterosexual men showing more penis arousal to female-female sexual activity and less arousal to female-male and male-male sexual stimuli, and homosexual and bisexual men being more aroused by films depicting male-male intercourse and less aroused by other stimuli.
Another study on men and women's patterns of sexual arousal confirmed that men and women have different patterns of arousal, independent of their sexual orientations. The study found that women's genitals become aroused to both human and nonhuman stimuli from movies showing humans of both genders having sex (heterosexual and homosexual) and from videos showing non-human primates (bonobos) having sex. Men did not show any sexual arousal to non-human visual stimuli, their arousal patterns being in line with their specific sexual interest (women for heterosexual men and men for homosexual men).
These studies suggest that men and women are different in terms of sexual arousal patterns and that this is also reflected in how their genitals react to sexual stimuli of both genders or even to non-human stimuli. It must be stated that sexual orientation has many dimensions (attractions, behavior,
identitySexual identity is a term that, like sex, has two distinctively different meanings. One describes an identity roughly based on sexual orientation, the other an identity based on sexual characteristics, which is not socially based but based on biology, a concept related to, but different from,...
), of which sexual arousal is the only product of sexual attractions which can be measured at present with some degree of physical precision. Thus, the fact that women are aroused by seeing non-human primates having sex does not mean that women's sexual orientation includes this type of sexual interest. Some researchers argue that women's sexual orientation depends less on their patterns of sexual arousal than men's and that other components of sexual orientation (like emotional attachment) must be taken into account when describing women's sexual orientations. In contrast, men's sexual orientations tend to be primarily focused on the physical component of attractions and, thus, their sexual feelings are more exclusively oriented according to
sexIn biology, sex is a process of combining and mixing genetic traits, often resulting in the specialization of organisms into a male or female variety . Sexual reproduction involves combining specialized cells to form offspring that inherit traits from both parents...
.
More recently, scientists have started to focus on measuring changes in brain activity related to sexual arousal, by using
brain-scanning techniquesNeuroimaging includes the use of various techniques to either directly or indirectly image the structure, function/pharmacology of the brain...
. Given that sexual feelings are the product of perceptions or fantasies which are processed in the brain, measuring brain regions' activity should further show how people of different sexual orientations differ in this respect.
A study on how heterosexual and homosexual men's brains react to seeing pictures of naked men and women has found that both hetero- and homosexual men react positively to seeing their preferred sex, using the same brain regions. The only significant group difference between these orientations was found in the
amygdalaThe ' are almond-shaped groups of nuclei located deep within the medial temporal lobes of the brain in complex vertebrates, including humans. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.-...
, a brain region known to be involved in regulating
fearFear is a distressing negative sensation induced by a perceived threat. It is a basic survival mechanism occurring in response to a specific stimulus, such as pain or the threat of danger...
.
Although these findings have contributed to understanding how sexual arousal can differentiate between genders and sexual orientations, it is still a matter of debate whether these results reflect differences which are the result of social learning or genetic or biological factors. Further studies are needed to clarify how much of people's reactions to sexual stimuli of their preferred gender are due to learned or innate factors.
Social detection
The attempt to detect sexual orientation in social situations is known as
gaydarGaydar is a colloquialism referring to the intuitive ability of a person to assess others' sexual orientations as homosexual, bisexual, or heterosexual. Gaydar relies almost exclusively on non-verbal clues and LGBT stereotypes...
; some studies have found that guesses based on face photos perform better than chance.
Birth order
Recent studies found an increased chance of homosexuality in men whose mothers previously carried to term many male children. This effect is nullified if the man is left-handed.
Influences on sexual orientation: professional organizations' statements
A legal brief dated September 26, 2007, and presented on behalf of the American Psychological Association, California Psychological Association, American Psychiatric Association, National Association of Social Workers, and National Association of Social Workers, California Chapter, stated:
And added in a footnote:
The
American Psychological AssociationThe American Psychological Association is the largest scientific and professional organization of psychologists in the United States. It is the world's largest association of psychologists with around 154,000 members including scientists, educators, clinicians, consultants and students. The APA...
, the
American Psychiatric AssociationThe American Psychiatric Association is the main professional organization of psychiatrists and trainee psychiatrists in the United States, and the most influential worldwide. Its some 38,000 members are mainly American but some are international...
, and the
National Association of Social WorkersThe National Association of Social Workers is a professional organization of social workers in the United States. It had over 150,000 members as of January 2008 and provides guidance, research, up to date information, advocacy, and other resources for its members and for social workers in general...
in 2006 stated:
The
American Academy of PediatricsThe American Academy of Pediatrics is the major professional association of pediatricians in the United States. The AAP was founded in 1930 by 35 pediatricians to address pediatric healthcare standards. It currently has 60,000 members in primary care and sub-specialist areas...
in 2004 stated:
The
Royal College of PsychiatristsThe Royal College of Psychiatrists is the main professional organisation of psychiatrists in the United Kingdom responsible for representing psychiatrists, psychiatric research and providing public information about mental health problems...
in 2007 stated:
The American Psychiatric Association stated:
United States
Demographics of sexual orientation
The multiple aspects of sexual orientation and the boundary-drawing problems already described create methodological challenges for the study of the demographics of sexual orientation. Determining the frequency of various sexual orientations in real-world populations is difficult and controversial.
Most modern scientific surveys find that the majority of people report a mostly heterosexual orientation. However, the relative percentage of the population that reports a homosexual orientation varies with differing methodologies and selection criteria. Most of these statistical findings are in the range of 2.8 to 9% of males, and 1 to 5% of females for the United States – this figure can be as high as 12% for some large cities and as low as 1% for rural areas.
Estimates for the percentage of the population that are bisexual vary widely, at least in part due to differing definitions of bisexuality. Some studies only consider a person bisexual if they are nearly equally attracted to both sexes, and others consider a person bisexual if they are
at all attracted to the same sex (for otherwise mostly heterosexual persons) or to the opposite sex (for otherwise mostly homosexual persons). A small percentage of people are not sexually attracted to anyone (
asexualityAsexuality , in its broadest sense, is the lack of sexual attraction and, in some cases, the lack of interest in sex. Sometimes, it is considered a lack of a sexual orientation...
).
Kinsey data
In the oft-cited and oft-criticized
Sexual Behavior in the Human MaleThe Kinsey Reports are two books on human sexual behavior, Sexual Behavior in the Human Male and Sexual Behavior in the Human Female , by Dr. Alfred Kinsey, Wardell Pomeroy and others and published by Saunders...
(1948) and
Sexual Behavior in the Human FemaleThe Kinsey Reports are two books on human sexual behavior, Sexual Behavior in the Human Male and Sexual Behavior in the Human Female , by Dr. Alfred Kinsey, Wardell Pomeroy and others and published by Saunders...
(1953), by Alfred C. Kinsey et al., people were asked to rate themselves on a
scaleThe Kinsey scale, also called the Heterosexual-Homosexual Rating Scale, attempts to describe a person's sexual history or episodes of his or her sexual activity at a given time. It uses a scale from 0, meaning exclusively heterosexual, to 6, meaning exclusively homosexual...
from completely heterosexual to completely homosexual. Kinsey reported that when the individuals' behavior as well as their identity are analyzed, most people appeared to be at least somewhat bisexual — i.e., most people have some attraction to either sex, although usually one sex is preferred. According to Kinsey, only a minority (5–10%) can be considered fully heterosexual or homosexual. Conversely, only an even smaller minority can be considered fully bisexual (with an equal attraction to both sexes). Kinsey's methods have been criticized as flawed, particularly with regard to the randomness of his sample population, which included prison inmates, male prostitutes and those who willingly participated in discussion of previously taboo sexual topics. Nevertheless,
Paul GebhardPaul H. Gebhard, born , was an American anthropologist and sexologist. Born in Rocky Ford, Colorado, he earned a B.S. and a Ph.D. from Harvard in 1940 and 1947, respectively. Gebhard followed Alfred Kinsey as the second director of the Kinsey Institute and served in that capacity from 1956 to...
, subsequent director of the Kinsey Institute for Sex Research, reexamined the data in the
Kinsey ReportsThe Kinsey Reports are two books on human sexual behavior, Sexual Behavior in the Human Male and Sexual Behavior in the Human Female , by Dr. Alfred Kinsey, Wardell Pomeroy and others and published by Saunders...
and concluded that removing the prison inmates and prostitutes barely affected the results.
Social constructionism and Western societies
Because sexual orientation is complex and multi-dimensional, some academics and researchers, especially in
Queer studiesQueer studies is the critical theory based study of issues relating to sexual orientation and gender identity usually focusing on lesbian, gay, bisexual, transgender and intersex people and cultures. Universities have also labeled this area of analysis Sexual Diversity Studies, Sexualities...
, have argued that it is a historical and
social constructionSocial constructionism and social constructivism are sociological theories of knowledge that consider how social phenomena or objects of consciousness develop in social contexts. A social construction is a concept or practice that is the construct of a particular group...
. In 1976, philosopher and historian
Michel FoucaultMichel Foucault , born Paul-Michel Foucault , was a French philosopher, social theorist and historian of ideas...
argued that
homosexualityHomosexuality is romantic or sexual attraction or behavior between members of the same sex or gender. As a sexual orientation, homosexuality refers to "an enduring pattern of or disposition to experience sexual, affectional, or romantic attractions" primarily or exclusively to people of the same...
as an identity did not exist in the eighteenth century; that people instead spoke of "sodomy", which referred to sexual acts. Sodomy was a crime that was often ignored but sometimes punished severely (see
sodomy lawA sodomy law is a law that defines certain sexual acts as crimes. The precise sexual acts meant by the term sodomy are rarely spelled out in the law, but are typically understood by courts to include any sexual act deemed unnatural. It also has a range of similar euphemisms...
). He wrote, "'Sexuality' is an invention of the modern state, the industrial revolution, and capitalism."
Sexual orientation is a concept that evolved in the industrialized West and there is a controversy as to the universality of its application in other societies or cultures. Non-westernized concepts of male sexuality differ essentially from the way sexuality is seen and classified under the Western system of sexual orientation. The validity of the notion of sexual orientation as defined in the West, as a biological phenomenon rather than a social construction specific to a region and period, has also been questioned within the industrialized Western society.
Heterosexuality and homosexuality are terms often used in European and American cultures to encompass a person's entire social identity, which includes self and personality. In Western cultures, some people speak meaningfully of gay, lesbian, and bisexual identities and communities. In other cultures, homosexuality and heterosexual labels do not emphasize an entire social identity or indicate community affiliation based on sexual orientation.
Some historians and researchers argue that the emotional and affectional activities associated with sexual-orientation terms such as gay and heterosexual change significantly over time and across cultural boundaries. For example, in many English-speaking nations it is assumed that same-sex kissing, particularly between men, is a sign of homosexuality, whereas various types of same-sex kissing are common expressions of
friendshipFriendship is a form of interpersonal relationship generally considered to be closer than association, although there is a range of degrees of intimacy in both friendships and associations. Friendship and association are often thought of as spanning across the same continuum...
in other nations. Also, many modern and historic cultures have formal ceremonies expressing long-term commitment between same-sex friends, even though homosexuality itself is taboo within the culture.
Anthropology, history, and sexology
Some scholars of
anthropologyAnthropology is the study of humanity. It has origins in the humanities, the natural sciences, and the social sciences. The term "anthropology" is from the Greek anthrōpos , "man", understood to mean mankind or humanity, and -logia , "discourse" or "study", and was first used in 1501 by German...
,
historyHistory is the discovery, collection, organization, and presentation of information about past events. History can also mean the period of time after writing was invented. Scholars who write about history are called historians...
, and
sexologySexology is the scientific study of human sexuality, including human sexual interests, behavior, and function. The term does not generally refer to the non-scientific study of sex, such as political analysis or social criticism....
have argued that social categories such as heterosexual and homosexual are not universal. Different societies may consider other criteria to be more significant than sex, including the
respective ages of the partnersAge disparity in sexual relationships refers to sexual relations between people with a significant difference in age. Whether these relationships are accepted and the question of what counts as a significant difference in age has varied over time; and varies over cultures, different legal systems,...
, whether partners assume active or passive sexual roles, and their social status.
Perception of sexual orientation and other people's reactions
One person may presume knowledge of another person's sexual orientation based upon perceived characteristics such as appearance, clothing, tone of voice, and accompaniment by and behavior with other people. Perceived sexual orientation may affect how a person is treated. For instance, in the United States, the
FBIThe Federal Bureau of Investigation is an agency of the United States Department of Justice that serves as both a federal criminal investigative body and an internal intelligence agency . The FBI has investigative jurisdiction over violations of more than 200 categories of federal crime...
reported that 15.6% of
hate crimeIn crime and law, hate crimes occur when a perpetrator targets a victim because of his or her perceived membership in a certain social group, usually defined by racial group, religion, sexual orientation, disability, class, ethnicity, nationality, age, gender, gender identity, social status or...
s reported to police in 2004 were "because of a sexual-orientation bias." Under the
UKThe United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
Employment Equality (Sexual Orientation) Regulations 2003, as explained by Advisory, Conciliation and Arbitration Service, "workers or job applicants must not be treated less favourably because of their sexual orientation, their perceived sexual orientation or because they associate with someone of a particular sexual orientation."
Politics and theology
Two researchers, raising (1995) 'serious doubt whether sexual orientation is a valid concept at all,' warned against increasing politicization of this area.
Professor Michael King stated, "The conclusion reached by scientists who have investigated the origins and stability of sexual orientation is that it is a human characteristic that is formed early in life, and is resistant to change. Scientific evidence on the origins of homosexuality is considered relevant to theological and social debate because it undermines suggestions that sexual orientation is a choice."
See also
- Affectional orientation
Affectional orientation is used both alternatively and side-by-side with sexual orientation. It is based on the perspective that sexual attraction is but a single component of a larger dynamic. To holders of this view, one's orientation is defined by whom one is predisposed to fall in love with,...
- Ascribed characteristics
Ascribed characteristics, as used in the social sciences, refer to properties of an individual, over which that individual has very little, if any, control. Typical examples include race, ethnicity, gender, caste, height, and sexual orientation. The term is more or less equally apt for...
- Hate crime
In crime and law, hate crimes occur when a perpetrator targets a victim because of his or her perceived membership in a certain social group, usually defined by racial group, religion, sexual orientation, disability, class, ethnicity, nationality, age, gender, gender identity, social status or...
- LGBT
LGBT is an initialism that collectively refers to "lesbian, gay, bisexual, and transgender" people. In use since the 1990s, the term "LGBT" is an adaptation of the initialism "LGB", which itself started replacing the phrase "gay community" beginning in the mid-to-late 1980s, which many within the...
(Lesbian, Gay, Bisexual, and Transgender)
- List of anti-discrimination acts
- LGBT rights by country or territory
- Human male sexuality
Human male sexuality covers physiological, psychological, social, cultural, and political aspects of the human male sexual response and related phenomenon...
, including non-western perspectives on sexual orientation
- Marriage
Marriage is a social union or legal contract between people that creates kinship. It is an institution in which interpersonal relationships, usually intimate and sexual, are acknowledged in a variety of ways, depending on the culture or subculture in which it is found...
- Same-sex marriage
Same-sex marriage is marriage between two persons of the same biological sex or social gender. Supporters of legal recognition for same-sex marriage typically refer to such recognition as marriage equality....
- Sexual orientation and military service
The military forces of the world have differing approaches to the enlistment of homosexual and bisexual individuals. The armed forces of most developed countries have now removed policies excluding non-heterosexual individuals...
- Sexual Orientation Hypothesis
The sexual orientation hypothesis is an hypothesis proposed by Donald McCreary in 1994 that describes male and female sexual orientation and their societal acceptance....
- Terminology of homosexuality
The terminology of homosexuality has been a contentious issue since the emergence of LGBT social movements in the mid-19th century. As with racial terms within the United States—such as negro, black, colored, and African American—the choice of terms regarding sexual orientation may imply a certain...
- Mental roots of sexual orientation
A theory about the development of sexual orientation and sexual arousal suggests that these behavior patterns are learned unconsciously from asexual experiences during childhood. The learning begins when the child distinguishes between men and women by the pitch of their voice...
Further reading
- Anders Agmo, Functional and Dysfunctional Sexual Behavior (Elsevier, 2007).
- Brum, Gil, Larry McKane, & Gerry Karp, Biology Exploring Life (John Wiley & Sons, Inc., 2d ed. 1994), p. 663. (About INAH-3.)
- De La Torre, Miguel A.
Miguel A. De La Torre is a professor of Social Ethics and Latino/a Studies at Iliff School of Theology, a religious scholar, author, and an ordained minister.-Biography:...
, Out of the Shadows, Into the Light: Christianity and Homosexuality (Chalice Press, 2009).
- Dynes, Wayne, ed., Encyclopedia of Homosexuality. (New York & London: Garland Publishing, 1990).
- Sell, Randall L., Defining and measuring sexual orientation: a review, in Archives of Sexual Behavior, 26 (6) (December 1997), 643–658. (excerpt).
- Wunsch, Serge, PhD thesis about sexual behavior (Paris: Sorbonne, 2007).
External links