Why People Become Attached After Intimacy

after-sex-attachmentYou’re in love?

Oh, really?

It has been widely observed that people in relationships –or, more problematically, people who aren’t in relationships– become attached after physical intimacy. Suddenly, after sex, proclamations of love and living happily ever after become commonplace. Two people become more attached to each other than they ever were before (and one person may become more attached than the other). What is happening? Does sex create love or increase feelings of love? Not exactly, but it can certainly give rise to feelings that mimic true love.

The Biological Reasons

So why do these feelings of “love” and attachment occur? Biologically, a major influence are the release of hormones and neurochemicals, especially oxytocin (also known as “the love or cuddle hormone”), dopamine, and vasopressin.

Oxytocin is released upon intimate touch and greatly increases feelings of love, trust, security, and bonding. It also decreases feelings of stress. When you cuddle, kiss, or engage in other forms of significant physical contact with another person, oxytocin is released and bonding occurs.

In both sexes, oxytocin levels rise dramatically during orgasm. At the same time, the neurotransmitter dopamine is released. Dopamine creates a strong sense of pleasure, excitement, and well-being. Dopamine is addictive — we want more and more of whatever brings us that pleasurable feeling.

The combined effects of oxytocin and dopamine cause you to not only feel attached to your partner, but to associate your sexual partner with a sense of pleasure, trust, and happiness. In men, vasopressin acts similarly to oxytocin to increase feelings of attachment and love.

attached-huggingDo these loving feelings last?

In a word, no.

Oxytocin and dopamine levels drop after orgasm. How steep these drop are and when they happen depends on the person and their unique biochemistry. Oxytocin, however, can be kept at high enough levels to sustain feelings of bonding if two people remain in contact. The problem is with dopamine and an associated hormone called prolactin.

At first, due to the action of oxytocin and dopamine, physical intimacy causes you to want more physical contact — you want that high that comes with the person you are attached to. But with a drop in dopamine levels comes a sense of irritability and depression. Over time, these highs and lows may become associated with your sexual partner.

Prolactin adds to these negative feelings. Prolactin levels increase after orgasm and work to curb sexual desire. But such high levels of prolactin eventually cause moodiness and feelings of anxiety and depression. In combination with the “downs” involved in a decrease in dopamine, you begin to see your “love” for what it is — a biochemical high.

So you’re not in love?

Sex is not love and the feelings created by sex can not sustain a relationship. What you feel post-coital is not love, but a very  strong sense of attachment created by the action of molecules in the body. It would be helpful to keep this in mind before you declare your love for someone you barely know, begin shopping for wedding rings and a new home, or otherwise commit yourself to a sexual partner.

What are your experiences with this phenomenon? Have you ever become attached after physical intimacy?

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Women, Men, and Empathy

empathyAre women more empathic than men?

Empathy is the ability to understand and share in the feelings and emotions of another person. Empathy is not limited to negative emotions, but includes positive and neutral feelings. The ability to empathize is connected to a person’s own capacity to feel and identify with their emotions.

Most popular opinions on differences in empathy between the genders hold that women are naturally more empathic than men. Women are traditionally and biologically the nurturing sex; women take care of others emotionally, as well physically and psychologically. But has the conclusion that women are more empathic been demonstrated on a large scale? Yes, but not in the way that most people would think. The greater empathic ability of women is likely not biologically determined, but social in origin.

A large number of studies across cultures and time periods have focused on gender differences in empathy. Most of these studies draw similar results: women show a greater capacity to identify with and understand others’ emotions. Women instinctively mirror emotional expressions more than men do. They are also more able to identify what a person is feeling. One study on brain activity and feelings found that while women identified the emotions they saw, their brain’s reflected these emotions: neural centers associated with emotions were activated. They could understand a person’s feelings in many settings — riding a bike, playing, walking.  On the other hand, while men could sometimes correctly recognize the feelings, men’s brain activity indicated they weren’t identifying with these feelings themselves: they weren’t empathizing. Instead they were simply using memory and pattern recognition to determine the emotions from those they had seen before.

baby-empathyOne may be tempted to think these studies show that gender differences in empathy are innate. But they don’t. These studies also show that men and women do not consistently differ in their ability to recognize emotions, most importantly, their own emotions. The first step towards empathizing is being able to identify emotions. This signifies that men and women are born with equal ability to empathize but these abilities begin to differ later on in life.  The brain can reflect exposure because it is plastic: it changes as a result of experience. In other words, the life experiences of women may be causing them to become more empathic, or those of men may be causing them to become less empathic, or both.

The main conclusion to be drawn from studies and surveys on empathy is that everyone is born with the capacity for empathy. People show differences in empathy not due to biology, but because their life has (or has not) been favorable to the ability to empathize.

See also:

The Johnny Depp Factor or Do Women Like Feminine Men?


I missed the “Johnny Depp” boat. I never understood why women swooned over Johnny Depp. I could see he had great bone structure, a modest personality, good acting skills. But was that it? Apparently not — according to some, Johnny has a perfect blend of many feminine features with some masculine features. In other words, he is the type of man many women dream of.

The theory that women like feminine men is a fairly new one. Men and women alike presume that women like the rugged, athletic, and muscle-bound men. But the idea that women like feminine men has been supported by a variety of unrelated studies.

In one popular internet study done in the United Kingdom, men with traditionally feminine features were rated as being better for long-term relationships. Judging digitally altered photos, participants chose the most feminine-looking men as warmer and more committed. Men with more masculine features were seen as better for the short-term.

The theory that women are more inclined to feminine men is used to support another theory. Amongst those researching the idea that homosexuality is partly hereditary, a prominent theory is that genes which predispose to homosexuality are actually several feminizing genes. These genes survive in the population because they are beneficial to those who only get a few of them. These feminized men have greater success with women and a better chance at reproducing. 

A large study involving self-identified gay and straight men and their siblings found evidence which supported both hypotheses. Brothers of gay men scored more “feminine” on a self-assessment than brothers of straight men, and these feminized men also had more female sexual partners on average. The most feminine men had better success with women. The study and similar ones are discussed by Simon LeVay in the detailed popular science piece Gay, Straight, and the Reason Why.

If feminine men are more attractive overall, but masculine men are better for the short-term, then Johnny Depp’s mix of feminine and masculine creates the ideal man. Whatever the reason, one thing is certain: I still don’t find Johnny Depp that attractive. But at least I have some idea why he is so alluring to others.

See also:

Creating Gender: Tracing Beliefs About Femininity


Is gender a reflection of nature or has gender become naturalized?

In the 2010 review publication “Brainstorm: The Flaws in the Science of Sex Differences,” Rebecca M. Jordan-Young presents examples of changes in popular and scientific views about what it means to be female. Jordan-Young, a sociomedical scientist and Assistant Professor of Women’s Studies at Barnard College says that, contrary to popular belief, today’s ideas on feminine behavior are not “common sense,” and are not biological. These concepts have changed over time and across cultures; ideas about what makes “femaleness” reflect society.

A widely accepted idea of today is that men have a greater sexual drive than women. But not too long ago, in the Renaissance Era, the popular belief of the day in Western Europe was the complete opposite. Women were believed to be the sexually insatiable gender, while men were more able to control their desires. In fact, a man who slept with many women was considered effeminate. Such a man was lacking in basic “manly” self-control. The idea that the desire for many partners and sexual encounters is essential to masculine biology is anything but accurate.

On the career and education front, considerable changes have taken place in the past few decades. In the 1960s and 1970s, it was believed that women were not “temperamentally” equipped for careers such as law, medicine, and dentistry. These careers involved a level of “systematizing” that women were not biologically suited for.

Statistics at the time reinforced popular belief — in 1960, 2 percent of all law degrees in the United States were awarded to women and only 1 percent of dental degrees were conferred to women. In about 40 years, these figures rose to 42 percent and 34 percent respectively, and are continuing to rise. To younger people this data is probably unremarkable, but less than a generation before, no one would have predicted these changes.

Gender stereotyping begins early, if “baby X studies” are any indication. “Baby X studies” refers to research that involves creatively manipulating the perceived sex of infants or toddlers to analyze how observers react to the children when they are labeled as “male” or “female”.

One of the best known studies involves the showing of a short film of a baby reacting to kinds of toys. The research found that when the baby was labeled as a “boy” viewers of the film saw his reactions as displaying pleasure or anger, where the “girl” was seen as displaying fear. The film involved only one baby and all viewers of the film saw the same clips — the only difference was that some viewers were told the baby was male and others were told the baby was female. Other baby X studies had similar findings; “girls” were believed to be expressing more fear or inhibition than “boys.”

“Brainstorm” poses an interesting question — does perceived gender influence what a person is believed to be capable of and what their personality is like? Is gender a reflection of biology or a reflection of society?

See also:

Gay, Straight, and the Reason Why: Chapters Ten and Eleven


Based on Chapters Ten and Eleven of Gay, Straight, and the Reason Why: The Science of Sexual Orientation by Simon LeVay

Chapter Ten: The Older-Brother Effect

Gay men have more older brothers, on average, than do straight men. The reason for this is biological and not social in nature. It is theorized that the mother’s womb may build up certain factors with each male pregnancy, that predispose her sons to homosexuality.

With each older brother, the likelihood that a man will be gay is estimated to be 33 percent. This seems like a high percentage, but the rate of homosexuality among men with no older brothers is only 2 percent. Thus having one older brothers raises the likelihood of homosexuality to less than 3 percent.

The older-brother effect seem to only apply to right-handed men, according to several studies. This suggests that more than one mechanism may lead to homosexuality in men, and that they do so in a mutually antagonistic way.

Chapter Eleven: Conclusions

Sexual orientation is a part of a group of gendered traits. It results from the prenatal sexual differentiation of the brain, with the primary determinants being genes and sex hormones. Some characteristics of the bodies and minds of gay men are shifted in a female direction compared with straight men, and some traits of the bodies and minds of lesbians are shifted in a female direction compared with straight women.

One hypothesis:

Testosterone is the central hormone in determining whether the brain and body develop in a male or female fashion. If testosterone levels are high enough during a critical time before birth the brain is organized in a typically masculine manner — including a tendency to be attracted to women. If levels are low, the brain organizes in a female manner.

The estimated heritability of homosexuality ranges around 30-50 percent; similar to estimates for many other psychological traits. Few major genes have been identified that could be responsible for influencing homosexuality. It is likely that, like most heritable psychological traits, sexual orientation is influenced by multiple genes, each contributing a small effect. Mutual inhibition functions between brain centers that contribute to sexual orientation as shown by the occasional change in sexual orientation that results from brain damage or reduction of hormones.

Does the idea that sexual orientation is linked to gendered traits stigmatize gay people by reinforcing stereotypes? This is debatable, but the findings that gay and straight people tend to differ in gender-related traits is a valuable insight for understanding the origins of sexual orientation. The blend of gender-variant and gender-typical traits of gay people is what enables them to make their unique contributions to society. Acknowledging this should foster acceptance of gay people as they are, instead of encouraging them conform with straight majority.

See also:

Gay, Straight, and the Reason Why Series:

Gay, Straight, and the Reason Why: Chapters Eight and Nine


Based on Chapters Eight and Nine of Gay, Straight, and the Reason Why: The Science of Sexual Orientation by Simon LeVay

Chapter Eight: The Brain

All mental characteristics have some representation in the brain; sexual orientation should be no different. As mentioned in the Introduction, a region in the brain known to regulate male-typical sexual behavior –INAH3– was reported to be significantly smaller in gay men than in straight men. Other regions of the brain have been found to differ between gay and straight people.

A study was done on the brains of lesbians and straight women. The study found that lesbians had significantly less gray matter than straight women, especially in a site known to control processes that differ between men and women. In another study, gay men in a sample were found to have female-typical brain volumes and connections, while lesbians were found to have male-typical volumes and connections. The connections were found  in the brain region known as the amygdala which, among other functions, controls processing of emotion and is involved in regulation of sexual functions.

Observations on human and non-human subjects suggest that male heterosexuality is not simply an attraction to the opposite sex, but active suppression of attraction to the same sex. Damage to or removal of the analogous region of INAH3 in male rats causes a change in their usual preference for female sex partners, to a preference for male partners. Homosexual attraction and/or behavior can occur in previously heterosexual men with Klüver-Bucy syndrome, caused by damage to the amygdala; the major source of input to INAH3 and nearby brain regions involved in sexuality. In addition, homosexual attraction can appear in a minority of men who are castrated for prostate cancer. These changes suggest that there are biological mechanisms for setting up sexual attraction to one sex that depends primarily on preventing attraction to the other sex.

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Gay, Straight, and the Reason Why: Chapters Six and Seven


Based on Chapters Six and Seven of Gay, Straight, and the Reason Why: The Science of Sexual Orientation by Simon LeVay

Chapter Six: The Role of Sex Hormones

There are no consistent differences in testosterone levels between gay and straight men, according to many studies. In contrast, up to one-third of lesbians (self-identified “butch”) may have higher testosterone levels in comparison to straight women. Markers of prenatal hormonal levels shows some differences that line up with sexual orientation.

Congenital Adrenal Hyperplasia (CAH) is a condition where a fetus is exposed to extremely high levels of male sex hormones. Women affected by CAH have been shown to be more masculine in mental and behavioral traits. Since homosexuality is linked to a variety of gender-atypical traits, it is unsurprising that studies have found CAH women to also be more homosexual, on average, than women not affected by CAH.

A similar, but opposite condition is androgen insensitivity syndrome (AIS), where the molecules that sense the presence of testosterone and other male hormones functions poorly or not at all. Genetic males with this condition grow up to look like women, identify as women, and most importantly, the majority of individuals with AIS are sexually attracted to men. This is consistent with the theory that sex hormones are a key determining factor in development of sexual orientation.

In genetically healthy individuals, similar findings have been presented. Sense of hearing differs between men and women and is affected by the greater prenatal exposure of men to testosterone and other male hormones. In studies, gay men have shown more female-like responses to sound and lesbians have shown more male-like responses. These findings are consistent with sexual orientation as an aspect of gendered traits.

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Gay, Straight, and the Reason Why: Chapters Four and Five


Based on Chapters Four and Five of Gay, Straight, and the Reason Why: The Science of Sexual Orientation by Simon LeVay

Chapter Four: Childhood

Boys and girls show fairly consistent differences in mental and behavioral traits; these traits are called “gendered traits”. Some of these differences arise through socialization, but many arise through biological factors such as hormone levels. Studies have shown that children who become gay adults (“pre-gay” children) are more likely to be gender-nonconformist, i.e. show characteristics typical of the opposite gender.

Two main types of methods are used to understand the characteristics of “pre-gay” children in comparison to “pre-straight” children:

  1. Retrospective Studies

The most widely used method. In retrospective studies, adults give descriptions of what they were like as children. Using this method, researchers have found that pre-gay boys are less physically aggressive than pre-straight boys and are more likely to take part in traditionally female activities. Overall, both pre-gay boys and girls were more likely to be gender-nonconformist, but for boys, such traits were much more predictive of adult homosexuality.

2.    Prospective Studies

A method where two groups of children –a control and a particularly gender-nonconformist group– are studied up to adulthood. These studies have made similar findings; noticeable femininity in boys is a predictor of adult homosexuality. Masculine traits in girls is not particularly a predictor of lesbianism — most girls who show traditionally male traits (“tomboys”) grow into heterosexual women.

Overall, these studies suggest that homosexuality is a part of a “package” of gender-atypical traits while heterosexuality is part of a set of gender-typical traits.

Chapter Five: Characteristics of Gay and Straight Adults

Studies on adults have found that mental and behavioral traits of gay men and women is shifted towards the opposite gender, but not completely opposite. Gay men show more of a gender shift than lesbians, who show no shift at all for some gendered traits.

Women tend to be more verbally fluent than men and better at tasks involving memory. Gay men score similarly to women on tests of verbal fluency and memory, while lesbians score similarly to men on such tests. Gay men and women are similar to their straight counterparts in aspects of sexuality, except in the roles preferred in sexual encounters. Some gay men are more receptive and some lesbians (so-called “butch” lesbians) are more dominant. Gay men strongly prefer more masculine partners and lesbians mildly prefer more feminine partners.

See also:

Gay, Straight, and the Reason Why Series:

Gay, Straight, and the Reason Why: Chapters Two and Three


Based on Chapters Two and Three of Gay, Straight, and the Reason Why: The Science of Sexual Orientation by Simon LeVay

Chapter Two – Why We Need Biology

The primary nonbiological theories for the origin of sexual orientation have encouraged the search for biological explanations. As a whole, these theories and their weaknesses make clear the need for biology in understanding sexual orientation and homosexuality.

  • Psychoanalytic Theories (pioneered by Sigmund Freud)

A. In males, the erotic instinct, also called the libido, is directed towards other males early on in life. This libido is later usually transferred to the mother in the infamous “oedipal stage.” In pre-oedipal homosexuality this transfer process doesn’t occur or is interrupted, causing lifetime homosexuality.

B. In oedipal  homosexuality, a young male is frustrated by his inability to be with the mother that he is so attracted to. He resolves this frustration by identifying with her and seeking male partners that remind him of himself.

C. In females, the young female suffers from an unresolved oedipal complex that has been redirected towards her father. She falls in love with women who represent the mother she has grown to love and hate.

The problem with these theories: There is no evidence, and the complexity and improbability of them count against their being true.

  • Learning Theories (Early Sexual Experiences)

A. A person’s first sexual contact determines their orientation. If their first contact is with a woman, then they will desire women, if with a man, they will be attracted to men.

The problem: Most people are aware of their sexual orientation as virgins. Also, young men in some non-Western cultures and single-sex boarding schools where sexual contact with other boys is common are no more likely to become homosexual adults.

B. Children who are molested are turned off the sex of their molester; e.g. girls who are molested by men become lesbians.

The problem: Since almost one-third of women will have an experience fitting a broad definition of sexual abuse, yet much less than one-third of women are lesbians, this theory is not likely true. Also, studies have found that lesbians are no more likely than straight women to have been abused as children.

  • Learning Theories (Gender Learning)

Children, after becoming aware of their gender, learn their sexual orientation from imitation of parents or others in their social environment.

The problem: Children who are reared as the opposite gender due to tragedies during infancy (e.g. males who lose their penis due to disorder or surgery) do not accept this gender. They are attracted to others of their assigned  gender and in most cases, revert back to their original gender.

Chapter Three – Outline of a Theory

The basic pathway that controls the development of sexual orientation (and other traits concerning gender) in nonhuman animals:

  1. Differences in sex hormone levels during development cause the brain to organize in a more male or female-like manner. These hormone levels are also modified by random variability, genetic differences, and environmental factors.
  2. Early sex hormone levels and the resulting differences in brain development influence preference for male and/or female partners later on in life.

This pathway appears to be the same route by which humans develop sexual orientation.

See also:

Gay, Straight, and the Reason Why Series:

Gay, Straight, and the Reason Why: Introduction and Chapter One


Note: I am currently reading a nonfiction piece by neuroscientist Simon LeVay entitled Gay, Straight, and the Reason Why: The Science of Sexual Orientation. For the next few weeks, at the beginning of each week, I’ll be publishing a summary of a chapter or two of the book.


Simon LeVay, a British-American and openly gay neuroscientist gained media attention in the early ’90s when he published a groundbreaking paper in the journal Science. The article, entitled “A difference in hypothalamic structure between heterosexual and homosexual men”, detailed his study on the brains of late humans which found that a region in the brain known to regulate sexual behavior was considerably smaller on average in gay men than in heterosexual men. This paper and similar papers of the time inspired new biological research into the contentious question: Why are gay people gay?

In Gay, Straight, and the Reason WhyLeVay outlines the research that has taken place since then and lays the foundation of a credible theory for the biological origins of sexual orientation via gender.

Chapter One – What is Sexual Orientation?

Sexual orientation is usually judged on the basis of a person’s sexual attraction to others — opposite sex attraction means heterosexuality, same sex attraction is known as  homosexuality, sexual attraction to both sexes equals bisexuality. Sexual orientation, contrary to belief, has little to nothing to do with sexual behavior, i.e. the extent to which a person has sexual contact with men or women. Sexual behavior is influenced by a variety of factors which are not a part of actual attraction, such as availability of sexual partners and a person’s sense of morality. Sexual attraction itself can be divided into two parts — physical attraction; the desire to engage in sexual contact, and romantic/emotional attraction; the desire for non-sexual psychological union.

Sexual orientation in men and women is generally stable throughout life, but moreso for men than for women. Some women but few men have true changes in sexual orientation later on in life.

Heterosexuality is far and away the most common sexual orientation for both men and women. How many people in the world are non-heterosexual (homosexual or bisexual)? Most surveys across the globe have resulted in similar numbers — about 3.5 percent of men and 1.5-2 percent of women in the world have attraction to persons of the same sex. Non-heterosexual men are mostly homosexual, while non-heterosexuality in women is divided close to evenly between homosexual and bisexual.

Gay and bisexual people have existed across time periods and cultures. Studies in large cities in non-Western countries such as the Philippines and Guatemala have shown that gay men exist in around the same numbers as those that live in large Western capitals. Ancient Greek writings suggest that the sexual attraction of some men and women for those of their gender was well-known and tolerated. This evidence suggests that homosexuality has a biological rather than social origin.

See also:

Gay, Straight, and the Reason Why Series: