Sex and Addiction

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Sex has many characteristics in common with addictive behaviors. Regulated by the brain's limbic system or "primitive brain," sex is driven by the region known as the reward circuitry. Dopamine, the craving neurochemical that impels fertilization behavior, also impels addictions to substances. This article examines how dopamine’s unnerving high/low cycle tends to promote emotional separation between mates and increase susceptibility to addictions. It suggests an ancient, but forgotten, way of making love that appears to heal the separation urge, and soothe cravings and depression.

Biology Has Plans for Our Love Lives

There is a common biological mechanism at work behind such diverse phenomena as the one-night stand, the sexless marriage, high rates of infidelity, and porn addiction. It produces the universal experience that "the honeymoon never lasts longer than a year," a reality confirmed in a recent study of the healthiest, happiest four percent of 2200 newlywed couples (Kiecolt-Glaser, 2001). It is why close friendships that bloom into love affairs so often turn sour. Essentially, humans are programmed to lose interest and then seek the stimulation of a novel partner, thereby increasing their offspring's genetic variety.

Biology uses powerful neurochemicals to achieve its agenda. For example, at a neurochemical level, falling in love is a lot like taking recreational drugs according to anthropologist Helen Fisher (Fisher, 2004). She shows how we are wired for three programs: lust, romantic love, and attachment. estranged coupleHowever, all too often mates find that they are also wired for a fourth program: emotional separation. Even when this built-in urge to separate doesn't split couples apart, it can kindle frustration, disharmony, a sense of stagnation, and cravings for other partners or for addictive substances.

When couples drift apart, they cheat themselves of the most beneficial gifts of intimacy. Studies show that close, trusted - and especially, harmonious - companionship is associated with increased longevity (Young, 2004), faster healing (DeVries, 2004), and lower rates of illness (Coyne, 2001), depression and alcoholism. (Horwitz, 1996) In short, biology asks us to make costly sacrifices just for a few more shots at genetic immortality.

In Love & Survival, Dean Ornish points out that love and intimacy are more powerful determinants of health than improved diet, stopping smoking, genetic make-up, more exercise, or prescription drugs. If companionship came in drug form, doctors who failed to prescribe it would be guilty of malpractice. (Ornish, 1998) Research suggests that oxytocin is behind these gains. As the authors address later in this article, experience reveals that lovers can train themselves to produce steadier supplies of oxytocin, while eluding the high/low separation trigger entirely.

Sex’s Hidden Hangover

What neurochemical mechanism drives intimate partners apart with such predictability? Astonishingly, it is built right into fertilization-driven sex. Over-stimulation of the limbic system triggers sexual satiation neurochemicals, which radically change our outlook toward each other. Unlike other mammals, who confine their mating frenzies to periods of estrus, humans can become sexually aroused at any time. Unfortunately, the blasts of dopamine that accompany sexual climax are potentially highly addictive and would interfere with other evolutionary priorities, such as hunting and gathering or feeding infants. Indeed, when researchers wired rats so that they could push a lever in their cages to stimulate the nerves on which dopamine acts, the rats pushed the lever until they dropped, not stopping to eat or mate (Olds, 1954).

To protect against this result, humans, too, possess a mechanism for sexual self-regulation. Ours, however, is more akin to starting and stopping in heavy traffic, leaving us vulnerable to intense cravings and relationship friction. What evidence is there that sex over-stimulates the brain? In 2003, a Dutch scientist reported that brain scans of people having orgasm resemble scans of a heroin rush (Holstege, 2003). Dopamine soars during copulation and orgasm. (Putnam, 2001)

These natural highs are only the first part of a neurochemical roller coaster ride - a ride that is essentially a sublte form of the cycle of all addictions. As we will see in a moment, after orgasm, dopamine plummets, prolactin soars, and androgen receptor activity drops off for up to a week. In short, "what goes up must come down," returning us to homeostasis. dopamine hangover Sadly, these subsequent neurochemical shifts lead to radical changes in perception, coloring our perception and altering our behavior.

When the neurochemistry of passion pounds between our ears, we see "Mr." or "Ms. Right." When the hangover kicks in, we may see "Mr. Hyde" or "Medusa." Or we "need space," overreact to remarks, feel needy, or find third parties compellingly attractive. During this natural recovery period we may also experience intense cravings, as we unconsciously seek to raise our dopamine levels again.

The Science Behind the Hangover

Recent neurochemical discoveries reveal three components of the post-orgasm hangover.

Dopamine The first of these is the sudden drop in dopamine that follows orgasm. At ideal levels, dopamine equates with feelings of well-being and healthy decision-making. We feel optimistic and open, much like pre-pubescent children, who have not yet climbed aboard the dopamine roller coaster and are delighted by everything from bugs to Barbies.

Dopamine Levels

Dopamine chart

At high levels, however, dopamine is the "I’ve got to have it, whatever the repercussions" neurochemical that lights up the brain's reward circuitry. It renders us single-minded and demanding. Biology employs this powerful means to motivate behaviors vital to survival and passing on genes, such as eating, drinking, taking risks, and, above all, engaging in fertilization behavior.

Yet, our culture, unlike that of our ancestors in whom this mechanism evolved, offers countless opportunities to over-stimulate ourselves with dopamine: alcohol, compulsive shopping, recreational drugs, junk food, and so on. Indeed, we do not even have to leave our computers to accommodate our addictions. Predictably, high levels of dopamine are associated with addictions, gambling, fetishes, anxiety, and so on.

When dopamine drops after orgasm, it falls below ideal levels, and can change our whole outlook on life. Low dopamine is associated with depression, feeling unable to love, and, again, addictions, as sufferers desperately seek to feel better. Fertilization-driven sex, in effect, pushes us back and forth from one dopamine extreme to the other. Either extreme can bring out the worst in us, and the resulting mood swings themselves can make intimacy bewildering. Prolactin-Dopamine relationship chart


To keep the brakes on for a while, biology employs an additional neurochemical: prolactin. Prolactin performs many functions, and it also appears to play a prominent role in regulating sex. As dopamine drops after orgasm, prolactin immediately rises in both men and women, acting as a sexual satiation mechanism. (Kruger, 2003) In men, it no doubt contributes to the "roll over and snore" phenomenon. In women, its effects may affect mood. Researchers do not yet know how long prolactin levels stay up in humans after orgasm, but in female rats prolactin surges continue for two weeks after mating, even if they are not pregnant. (Polston, 2001)

During withdrawal from cocaine (another high-dopamine activity), prolactin levels rise and require two weeks to return to normal levels. (Contoreggi, 2003) Prolactin may influence our mating behavior beyond serving as sexual brakes. Like dopamine, it affects our moods and behavior. Prolactin is touted as a pleasant, satiation neurochemical (in relation to sex), but it has many jobs in the body, and it appears to be a stress hormone, associated with feelings of despair. For example, when first caged, wild monkeys showed high levels of cortisol for a couple of days while they tried to escape. Once they realized they were trapped, prolactin levels rose. Those tested at seven months had the highest levels of prolactin. (Suleman, 2001)

High prolactin could be contributing to the long-term discouragement that seems to overtake so many intimate relationships. Jeremy Heaton, MD maintains that as we learn more about sex and aging, prolactin will be a major player. (Heaton, 2003) Certainly, the conditions associated with high levels of prolactin closely resemble the list of things that couples complain about as their honeymoons end.

Symptoms associated with excess prolactin
Women Men
Loss of libido Loss of libido
Mood changes / depression Mood changes / depression
Hostility, anxiety Impotence
Headache Headache
Menopausal symptoms, even when estrogen is sufficient Infertility
Signs of increased testosterone levels Decreased testosterone levels
Weight gain Weight gain
Intercourse may become painful because of vaginal dryness

Androgen Additional evidence of a lingering post-orgasm hangover comes from sexually exhausted male rats. The number of androgen receptors decreases in the hypothalamus, curtailing the effects of testosterone and altering behavior. Changes linger for up to seven days, corresponding with the rats' lack of libido. Also see Men: Does Frequent Ejaculation Cause a Hangover?.

More Evidence of a Post—passion Hangover

For better or worse, there is one way to jumpstart flagging libido during the post-passion hangover period. Unfortunately, it offers more proof that biology cares fervently about propelling genes into the future, and little about sustaining the many benefits that flow from harmonious companionship (at least beyond the initial mating frenzy of the honeymoon period - see Will Orgasms Keep You in Love?). No matter how sexually exhausted and uninterested a rat is in a current mate, if a novel female is introduced, the male will rise to the occasion and perform his fertilization duties. (Fiorino, 1997) This process can be continued until the gallant rat nearly dies.

The neurochemical hangover discussed above is the key to understanding the "Coolidge Effect." As dopamine drops, the rat loses interest in his mate and copulation ceases. When a new partner appears, dopamine soars again and the rat revives long enough to deliver more genes. candy hearts

The "Coolidge Effect" has been observed in every species tested, and is not confined to males. Female rodents also prefer to seduce new mates, (Lester, 1988) except when oxytocin is injected into key parts of their brains, as we will see in a moment. Abundant anecdotal evidence suggests that the "Coolidge Effect" also manipulates humans. As a man from sensual Los Angeles once related, "I quit counting at 350 lovers, and I'm still confused as to why I lost interest in all of them sexually so quickly. Some of those women are really beautiful." His third wife had just left him for a Frenchman.

In short, biology's mechanism for regulating sexual behavior sets up a cycle of highs and lows that drives a wedge between lovers. Indeed, when anthropologists studied two hunter-gatherer cultures believed to be representative of our distant ancestors (the !Kung of Africa and the Mehinaku of South America), they found exactly this pattern at work: lots of romance and impulsive sexual behavior - and lots of churning and heartache in intimate relationships. Unless we consciously intervene, our neurochemistry programs us for intense passion followed by emotional alienation. Helen Fisher estimates that humans are designed to stay together less than four years, the time it takes to get a child on its feet. Across 58 cultures worldwide, she found that divorce rates peaked at this point. (Fisher, 1995)

Can Sex Heal Addiction?

Changes in dopamine, prolactin and androgen receptor levels powerfully affect our mood, our level of desire for intimacy, our perception of our mates, and our susceptibility to addictive activities and substances. spilled wineAt a brain chemical level, sex sets up an addictive cycle of highs and lows. A burning desire to make love may not indicate that equilibrium is restored; we may, in fact, unwittingly be using our mate to self-medicate to cope with a neurochemical hangover. Orgasm, like any other "fix," is temporary relief, the prelude to discomfort and the search for another high. Drug companies now market dopamine agonist drugs to increase libido. (See 'Super Size Orgasms') They perpetuate this very cycle, with its attendant risks of relationship disharmony and susceptibility to other addictions.

Again, the reward circuitry that governs sex is the same one that drives all addictions. Those who treat sexual addiction frequently discover dual diagnoses (alcoholism, gambling, drug use) among their patients. Hamsters who have mated react to amphetamines more than virgin hamsters (Bradley, 2001). Teens who are sexually active use more recreational drugs than those who are not (Columbia University, 2004).

In an important study from the Pacific Institute for Research done in 2005, the authors concluded that "sex, drugs and alcohol among teens actually precede—and apparently lead to—the onset of adolescent depression, which contradicts the common belief that depressed teens may be 'self-medicating' through substance abuse and sex." 1

When we allow biology or its surrogate, prescription drugs, to govern our love lives we amplify a weak point in our design. Yet the existence of this weak point suggests a possible solution. Some years ago, at the beginning of their romance, the authors experimented with an ancient approach to lovemaking in which lovers avoid orgasm during sex in favor of a less goal driven, more affectionate approach.

The result of this practice is improved health, harmonized emotions, the cessation of desires and impulses, and, at the highest level, the transcendent integration of the entire energy body. Lao Tzu, Hua Hu Ching, third-century BCE

To their surprise, within four months, Gary quit drinking. He had suffered from a 12-year, closet addiction to alcohol, which he had long tried unsuccessfully to overcome. Within a year, he was also off of prescription antidepressants. (Chronic depression had run in his family.) He felt better, was calmer and more productive, and, for the first time, found it easy to sleep through the night with his soon-to-be-wife. Marnia's chronic yeast infections and urinary tract infections disappeared.

What had happened? Two things. First, the authors had escaped the dopamine high/low cycle described above, with its attendant mood swings and emotional friction, enabling them to stay together harmoniously. Second, they were unconsciously sustaining higher levels of oxytocin with a regime of regular exchanges of affection and caring attention. This became clear when Gary analyzed recent brain chemistry research in an effort to understand what was occurring.

Like most neurochemicals, oxytocin performs different functions depending upon where and when it is released. For example, dripped into a pregnant woman as "pitocin," it can bring on birth contractions. It also causes breast milk to be ejected. However, in recent years scientists have discovered many surprising functions of oxytocin. One of the most significant is its ability to bond us with each other - when it is released in the limbic system. Oxytocin is behind parent/child bonds, deep friendships, even the conviction that one's dog is the most adorable creature in the world. We could not fall in love without it. Now, scientists are begining to elucidate the neurobiology of how oxytocin might ease dopamine-based cravings. See Oxytocin modulates dopamine-mediated reward in the rat subthalamic nucleus.

Oxytocin is not about "lust," though. It is behind the selfless desire to nurture, and be close to, another. It also plays a role in monogamy. Injected into the brain of a promiscuous rodent, it will make a familiar partner more appealing than unfamiliar partners. (Harmon, 2002) Just as dopamine and its hangover are the keys to our promiscuity (because the grass may soon look greener elsewhere) oxytocin seems to be the key to wanting to stay with one partner. Can we just pop an oxytocin pill and stay deeply in love? No. Oxytocin does not cross the blood/brain barrier, except by means of peripheral injection or risky nasal sprays. This means that if we want the many benefits that come from its presence in the limbic system, we would be wise to employ the behaviors that encourage its production there.

Now, scientists are begining to elucidate the neurobiology of how oxytocin might ease dopamine-based cravings. See Oxytocin modulates dopamine-mediated reward in the rat subthalamic nucleus.

Oxytocin's Many Benefits

In the course of his analysis, Gary also learned that oxytocin is the answer to the question, "What is the mechanism by which love and affection positively affect our health?"

Fear - Cortisol Love - Oxytocin
Aggression Anti-stress hormone
Arousal, Anxiety, Feeling stressed-out Feeling calm and connected, Increased curiosity
Activates addictions Lessens cravings & addictions
Suppresses libido Increases sexual receptivity
Associated with depression Positive feelings
Can be toxic to brain cells Facilitates learning
Breaks down muscles, bones and joints Repairs, heals and restores
Weakens immune system Faster wound healing
Increases pain Diminishes sense of pain
Clogs arteries, Promotes heart disease and high blood pressure Lowers blood pressure, Protects against heart disease
Obesity, Diabetes, Osteoporosis ---

-- Oxytocin reduces cravings. When scientists administered it to rodents who were addicted to cocaine, morphine, or heroin, the rats opted for less drugs, or showed fewer symptoms of withdrawal. (Kovacs, 1998) Oxytocin also reduces cravings for sweets. (Billings, 2006)

-- Oxytocin calms. A single rat injected with oxytocin has a calming effect on a cage full of anxious rats. (Agren, 2002)

-- spilled wineOxytocin appears be a major reason that SSRIs ease depression, perhaps because high levels of cortisol are the chief culprits in depression and anxiety disorders. (Uvnas-Moberg, 1999)

-- Oxytocin increases sexual receptivity and counteracts impotence, which is why this other way of making love remains pleasurable. (Pedersen, C.A., 2002), (Arletti, 1997)

-- Oxytocin counteracts the effects of cortisol, the stress hormone. (Legros, 2003) Less stress means increased immunity and faster recovery.

Oxytocin isn't all hearts and flowers, however. For some of it's less heart-warming attributes see Liquid Love and Oxytocin Revisited. Yet there's no indication that oxytocin released naturally in response to normal attachment cues would cause unwanted side effects.

The bonding, soothing qualities of oxytocin explains why companionship can increase longevity - even among those who are HIV positive (Young, 2004). Or speed recovery: wounded hamsters heal twice as fast when they are paired with a sibling, rather than left in isolation (Detilliona, 2004). It may also explain why, among various species of primates, care-giving parents (whether male or female) live significantly longer. (Cal Tech, 1998) It also reduces stress: Influence of a ‘Warm Touch’ Support Enhancement Intervention Among Married Couples on Ambulatory Blood Pressure, Oxytocin, Alpha Amylase, and Cortisol

Incidentally, a surge of blood-level oxytocin often accompanies orgasm, which sometimes causes people to conclude that more orgasms must lead to tighter emotional bonding. Who knows? First, researchers suggest that oxytocin's role during orgasm is solely to bring on the contractions that move semen to various strategic locations, just as oxytocin causes smooth muscle to go into birth and nursing contractions. (Vignozzi, 2004) It is not clear that oxytocin levels surge at orgasm in the limbic system - where bonding occurs. In any case, they soon drop, as does the other neurochemical most important for sustaining bonds: dopamine. This is why orgasms may not keep you in love.

Second, oxytocin is a less reliable marker of orgasm than the "shutdown" neurochemical, prolactin (Kruger, 2003), which means that oxytocin does not always rise at orgasm. In any case, when dopamine drops too low (after a passion bout), so does oxytocin - and lovers lose their desire for closeness. By contrast, when dopamine stays at ideal levels, it helps maintain oxytocin levels as well.

The interplay between these two neurochemicals is generally overlooked, which causes some to assume blindly that we can consistently have high dopamine and high oxytocin. Finally, even if a surge in bloodstream oxytocin at orgasm does somehow encourage bonding, it should be obvious that something even more powerful is eroding that bonding in most long-term relationships. If orgasm cemented relationships, then marriages would be more stable, not far less stable, than they were 50 years ago.

Meanwhile, how can we cause the brain to release oxytocin where it best stabilizes our brain chemistry and benefits our relationships? Daily caring touch, especially stroking, is one way. Another is selfless giving - or nurturing another - as a parent would a child. Neurochemicals and behavior tend to be circular. That is, a change in behavior induces changes in neurochemistry, and vice versa. Close, trusted companionship also seems to promote the production of oxytocin. The more we produce, the more receptive we are to it. Oxytocin receptors do not down-regulate as dopamine receptors do. This means we do not need an ever-increasing level to get the same feeling of being in love. evolutionMates appear more and more appealing over time, rather than the reverse.

Sustained production of oxytocin is the loophole in biology’s plan, since it helps to keep us from moving on to new partners. (No, oxytocin nasal spray will not bond you to your mate, although it appears to reduce hyper-vigilance.) Finally, more affectionate, non-goal-driven lovemaking may aid addicts because it encourages sustained production of oxytocin.

The insight that sex can heal cravings is thousands of years old (Lao Tzu, trans. 1992), and has resurfaced in various cultures since then (Gnostics, Robinson, trans.1978), (Karezza, Stockham, 1902). The link between sex and addiction deserves careful investigation. Perhaps the ancient Taoists were wise to teach that sex is like fire or water.

"Both fire and water can kill, yet both may also bestow life." Taoist Proverb


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