Ever heard the familiar complaints: "All he wants is sex!" and "She's just not the hot babe I got together with!"? Well, they seem to be backed up by actual research. A new study shows that women tend to lose sexual interest in their mates, while men lose affectionate interest in theirs. Researchers found that after 4 years, less than half of the 30-year-old women polled wanted regular sex. Men's desire to engage in tenderness for its own sake fell off just as quickly. (Full article and link to research abstract.)

Researchers didn't bother to explain why the men's affection fell off, and they concluded that a woman loses interest in sex once she "has her mate" in a secure relationship. (However, the declines were not just observed in married couples.) The researchers seem to rest their conclusion on a secondary finding: women who were less well educated than their mates stayed sexually active longer, implying (in the researchers' view) that women's sexual desire is governed primarily by the social status of their mates. ¹

Digging Deeper

There's enough research on the effects of sex on the brain (via neurochemicals) to support a more illuminating hypothesis to explain these findings. In fact, it saddens us that researchers fail to consider a possible neurochemical explanation, for reasons we will explain in a moment.

Unpopular as the notion may be, there is growing evidence that the effects of sex on the brain are in some ways similar to the effects of recreational drugs. That is, orgasm is the high phase of a cycle that also has a low phase. During the low phase, lovers' neurochemistry is profoundly different than during the orgasm phase. It changes the way they see each other for the worse.

In addition to evidence of a low phase in the orgasmic sex cycle, or "passion cycle," there is evidence that may begin to explain why the sexes tend to behave differently from each other after exhausting their mutual magnetism with passion. The study suggests that in most men, this natural drop (which corresponds with a drop in a neurochemical called dopamine in specific parts of the brain) exacerbates the addictive cycle of sex. In most women it causes apathy or mood swings, and may actually dampen libido (unless they move toward the "male" addictive cycle). Over time, these recurring, distinctive withdrawal behaviors drive the sexes apart...and perhaps on to new (or additional) mates.

Unfortunately, by not addressing our inherent passion cycle, we humans do three things:

• We perpetuate the belief that the only normal sex is sex that keeps lovers locked in a deteriorating cycle of highs and lows.
• When the lows overtake us, this blindspot leaves us vulnerable to the clumsy, and possibly dangerous, sexual enhancement drugs marketed (and soon to be marketed) by the pharmaceutical companies.
• By indirectly targeting the wrong problem for correction, we discourage ourselves from investigating the various lovemaking traditions that would protect our lovemaking from this addictive cycle, and strengthen our emotional bonds.

Sex is addictive?

Recent brain science supports the idea that orgasm is the beginning of a cycle, not unlike shooting heroin.² (Also see 'Mind-benders: When 'Natural' Is Risky' ) Following the initial "bliss" of intense passion, there is a withdrawal phase, which can be uncomfortable.

The most important neurochemical player in this cycle seems to be dopamine (also dubbed "the molecule of addiction"). At moderate levels dopamine is a wonderful contributor to feelings of wellbeing. It makes us cheerful, optimistic, curious, and willing to try new things. It also helps us stay focused on goals and choose rewarding courses of action - like mating.

However, too much dopamine in the reward circuit of the brain is not a good thing because when it goes too high it automatically drops afterward. Until we recover, it remains abnormally low, creating withdrawal symptoms. Indeed, low dopamine³ can give rise to surprisingly intense psychological distress, which profoundly affects mood and outlook. (In the case of orgasm, other brain chemical changes may also contribute to this "hangover" effect, such as a subsequent rise in prolactin,⁴ and a decrease in testosterone receptors that can last up to a week.⁵)

In short, after exhausting their passion, lovers have good reason not to "feel like themselves" for some indeterminate period of time.⁶ Unfortunately, they then project these natural changes onto each other, so they feel - and behave - differently toward one another. Sooner or later, this recurring malaise often pushes mates out of love. In fact, we believe this natural perception shift will turn out to be the most important factor in the disharmony between the sexes. Yet, it's such a fundamental aspect of our nervous system that we may not recognize it until we make love differently.

His and Hers?

The results of the study mentioned earlier suggest that the genders tend to react to the underlying cycle in characteristic ways - men by withdrawing emotionally, women by withdrawing sexually. In fact, however, everyone reacts differently to this drop off of dopamine. Apathy, irritability, mood swings, a sense of depletion, emotional neediness, emotional numbness, and an urge to pursue addictive behaviors or substances, are common responses to the post-passion withdrawal phase in both sexes.

In other words, post-passion neurochemical strategies are not strictly gender-specific. It is not always men who want more sex, or women who want more non-goal-oriented affection. In relationships where the woman's libido is higher than her mate's, he often loses interest in sex - and the woman is equally disinclined to be generous with unconditional affection (i.e., affection without orgasm as her goal).

This phenomenon suggests to us that testosterone may also be a key player in determining sexual strategy. For example, men naturally have more testosterone than women, and testosterone has been shown to stimulate the release of dopamine in the reward circuit. Similarly, high libido in women is a function of their higher than average testosterone. Such women may also be particularly susceptible to the dopamine cycle, and therefore prone to experience orgasm as especially addictive. In general it seems that the discomfort of the withdrawal phase is more severe for those who are very sexually-active (engaging in pornography/masturbation). Could it be because they are (or become) more dopamine-sensitive?

In short we hypothesize that the passion cycle has very distinctive effects on "male-model" lovers (whether male or female), and equally distinctive effects on female lovers. Let's consider the differences between these two models in more depth.

Two strategies for staying in love

Recent research on pair bonding⁷ suggests that both oxytocin⁸ and dopamine are necessary for the feeling of being "in love" - that is, to maintain what scientists call a pair bond.⁹ Both men and women want to remain in that "in love" state. Leaving aside the initial rush of mutual infatuation neurochemistry, which affects both lovers,¹⁰ what strategies do lovers use when they strive to retrieve that "in love" sensation - as recurring discomfort shifts perception for the worse?

"My Big Libido"

We humans tend to believe that an intense urge to have sex is proof of a "mighty libido," but it may turn out that in today's porn-saturated, pro-orgasm culture, it is more often simply proof of "intense withdrawal discomfort" caused by low dopamine following sexual satiation (over-stimulation of the reward circuit of the brain). In effect, a burning desire to make love is not evidence that the withdrawal (or low dopamine) phase has passed; it may instead signal its nadir.

As explained, a male-model lover in the "ebb" portion of the passion cycle is desperate to get his dopamine up - something passion can easily achieve. Not only that, orgasm will usually temporarily bump up his oxytocin.¹¹ So his strategy for returning to feeling "in love" is to strive for orgasm with his partner. Briefly, his strategy succeeds.

Unfortunately, however, when his dopamine plummets shortly afterward, his emotional bond also weakens again. This leaves the post-passion lover in a particularly uncomfortable bind: emotionally distant (because the dopamine, or desire, element of the bonding mechanism is largely absent) and (very soon) sexually-frustrated. One possible outcome is a pattern of cold behavior, completely lacking in affection, punctuated by brief periods of lust (excruciatingly portrayed by Leo Tolstoy in The Kreutzer Sonata).¹²

In a sense, for the male-model lover, libido has two rather distinct faces - which have noticeably different effects on his level of spontaneous affection and his perception of his mate. One type of libido arises from a genuine urge to merge (a search for deeper intimacy with another). The other is primarily the urge to seek relief during the withdrawal phase that follows sexual satiation. During the second one his urge to be affectionate naturally declines and he may perceive his lover as unusually irritating or draining.

Understandably, humanity confuses these two - very different - underlying states of mind, and fails to recognize an important truth about why a man's lovemaking affects a female partner so differently at different times. A superficial analysis instead concludes that her response is obviously due to her "unhealthy" libido.

Sex is not, in fact, just sex - regardless of the perspective of the male-model lover suffering from low dopamine. If it were, the more someone masturbated, the happier he would be. Sex to "scratch an itch" leads to fleeting relief, but not to sustained fulfillment.¹³ Moreover, when one is in a low-dopamine phase during the days after sexual satiation, one may be concerned not with a partner's well-being at all - but only with easing one's own discomfort. While under this influence, affection is most often an unwelcome delay of relief, and confined to the brief moments of intense passion. Such behavior does not indicate a fundamental character flaw; it's largely a consequence of the intent focus on elevating dopamine to comfortable levels as quickly as possible.

The tragedy is that the harder an uncomfortable male pursues relief, the more he may drive an emotional wedge between himself and his "frigid" lover - and the less inclined she may be to offer the nourishing comfort of sexual intercourse in the future.

We believe that future research will further clarify the interaction between testosterone and dopamine, and reveal why men (and perhaps anyone who heavily pursues orgasm via pornography, lots of hot foreplay, or masturbation) may be more sensitive to dopamine levels (both high and low).¹⁴ Either way, the withdrawal phase can be acutely uncomfortable for the male-model lover. It's difficult indeed to resist the urge to get a big "reward" from raising dopamine via a quick orgasm, with or without a partner.

Unfortunately, lacking an understanding of the complete passion cycle, a male-model lover fails to realize that a "relief-orgasm" guarantees another dismal withdrawal period just ahead. Like any addict, he has deferred his problem, but not resolved it. Today's media, however, assures him that this uncomfortable addiction cycle defines "healthy sexuality." And if his love life stalls, he is advised to increase the novelty in it (to raise his dopamine).¹⁵

However, as long as he uses "hot sex" as his benchmark of fulfillment, he is caught in an intensifying addictive cycle. The low points in the cycle can ultimately convince him that he needs sexual enhancement drugs. As one man wrote,

I think there is a correlation between porn viewing and erectile dysfunction. I am sure that if a study were actually done with honest men, we would see significant results. This is the type of issue people don't talk about. However, I think the porn industry is causing a huge problem in relationships and society in general. The porn industry takes advantage of the uninformed public by charging for the porn. Then the pharmaceutical companies sell us drugs to treat the side effects.

"My Broken Heart"

The female response to withdrawal discomfort generally leads to a different overall strategy. It may be heavily influenced by oxytocin, perhaps because a woman naturally produces more oxytocin than a man. As with dopamine, oxytocin has lots of benefits when at balanced levels.¹⁶ Research reveals that oxytocin tends to calm, speed healing, increase sexual receptivity, and counter the effects of cortisol (stress), cravings, and depression. Oxytocin is also linked to emotional bonds. Indeed, we could not fall in love without it.

However, as with dopamine, excessive oxytocin (or oxytocin binding to the "wrong" receptors) can have quite different effects. Recent research shows that relationship distress is actually associated with higher oxytocin (possibly due to high prolactin) — but does not counter a woman's stress response.¹⁷ In other words, her high oxytocin doesn't help her cope when she perceives disharmony in her relationship (a common perception during with withdrawal phase of the passion cycle). Indeed, high oxytocin may exacerbate her insistence upon a closer union (making her clingy, demanding, or irrationally jealous).¹⁸ She may also seek relief through processing her relationship woes with friends, shopping, eating chocolate ice cream, and so forth.

Low dopamine may contribute to the desperation that many women exhibit during this phase. Low dopamine tends to show up in both sexes as a sense of lack. (Other symptoms of low dopamine include depression, sleep disorders, and "restless leg" syndrome.) Yet, whereas low dopamine may make a man may feel depleted and emotionally distant (in between his attempts to self-medicate with orgasm), it takes a different form in a woman. Her sense of lack seems to manifest as a craving for reassurance.

She may believe that she is simply responding to her partner's changed (and less attentive) behavior. After all, it is often evident to the woman that feelings of genuine affection are absent (or geared strictly toward his arousal), and that he is in a selfish frame of mind. Being used as a "fix" is not at all the same experience as intercourse as a mutual act of nourishing intimacy. However, in our experience, her post-passion mood swings are predictable enough to be linked to her own passion cycle and its fluctuating neurochemicals. In short, regardless of her mate's actual behavior, she is likely to feel like her needs are not being met. As a friend in this phase of her romance wrote,

He mentioned he doesn't want to feel vulnerable. What happens is that I feel Love for him even more, which is frustrating. I've chosen the wrong man again.

All of this means that, during withdrawal, just as a man perceives his first order of business to be raising his dopamine with passion, a woman perceives her first order of business to be resolving the relationship disharmony that is associated with her elevated oxytocin (and prolactin?). Her exaggerated behavior not infrequently drives her partner away…indirectly causing her to fulfill evolution's command to end her relationship and move on.

The media's assurance that a happy sex life is one that conforms to the addictive passion cycle has unwelcome implications for women as well. Researchers tend to pathologize a woman's natural lack of response to a lover suffering from withdrawal (especially during her own withdrawal). Pharmaceutical companies are already seeking approval for drugs that would artificially elevate her dopamine with sexual enhancement drugs. These could very likely have risky side effects.

In truth, her libido is most likely dormant, not ill (as those who opt for affairs will attest.¹⁹) More significantly, such drugs cannot duplicate the subtle, complex neurochemical dance required to keep partners "in love." At best they can inflame the addictiveness of sex, and, sadly, the severity of the withdrawal phase itself - creating even more emotional friction.

Evolution Wins

Whatever the strategy, neither gender solves the problem of restoring the lost feeling of being "in love." Too often, couples try to duplicate mutual magnetism by fantasizing, watching pornography, engaging in more intense foreplay or novel positions. This tactic certainly has noticeable short-term effects, but, as a dopamine-increasing strategy, it ultimately intensifies the cycle of highs and lows. Therefore, it can create intense mood swings that erode the emotional bond of the couple.

Frequently, the woman, reflecting on the natural attentiveness of the early days of courtship, mistakenly concludes that the full correction lies in technique. "If only my partner would show more affection or engage in extended foreplay, then I would feel more satisfied." In fact, however, going through the motions of affectionate foreplay cannot entirely duplicate the fulfillment that accompanies mutual desire for deeper union. When either partner is suffering from withdrawal, sex simply doesn't feel the way it does when both are "in love."

Alas, evolution has shaped both men and women to slide from feeling "in love" toward feeling disillusioned. Selfishness and defensiveness replace mutual consideration as the basis of the relationship. This may explain the brevity of the "honeymoon" period during most relationships. One study found that the glow generally begins to fade in the second year of marriage.²⁰

In this way intimate relationships tend to become hostile or flat over time - and yet surprisingly rapidly. We say "surprisingly" because friendships and relationships with pets and children don't suffer such rapid, radical deterioration.

Why is the problem largely confined to intimate partners? To keep us moving on to new mates in order to increase genetic diversity. Unfortunately this evolutionary "move on" command works all too well. Over 95% of all mammals are non-monogamous.

In our experience, lovers have to change the way they make love if they would stay more affectionate, feel satisfied, and maintain a healthy libido. This solution, which is very ancient and found in diverse cultures, is the best protection against passion's neurochemical roller coaster ride.

My husband recently said that making love is like inflating a balloon. Having an orgasm is like popping the balloon, whereas if you finish without an orgasm it is like you are a balloon that takes several days to gradually deflate, leaving you much longer to enjoy the inflated feeling. (As I have mentioned before, I love how - even though he does not acknowledge any relationship harmony effects through this style of lovemaking, or anything wrong with orgasm - he prefers avoiding it because he simply feels better after.)

What really soothes sexual frustration?

Long ago, the Chinese noticed that ejaculation, although depleting physical reserves, has the opposite effect on sexual desire. "After an immediate postcoital letdown, there is a rapid psychological rebound and an intensification of erotic interest [and wet dreams]." This is consistent with the addiction cycle described above.

This insight also suggests a cure for sexual addiction: "When the ching is full, one is free of lustful thoughts."²¹ In other words, when one avoids feelings of depletion (low dopamine), one's sexual frustration declines.

The ancient Chinese solution? Make love frequently, but without the orgasm, and thereby gain the many benefits of sexual intimacy while avoiding the addictive high/low cycle of sex. This course protects mutual magnetism, or healthy libido. (We would define healthy libido as a genuine desire for the deeper intimacy of intercourse - which is not dependent upon climax for satisfaction.)

It is mutual magnetism, not simply lust, that supports a profound emotional connection with one's mate. The mainstream media cannot envision mutual magnetism without orgasm - or sexual frustration. However, the result of a connection based on love is a natural increase in sexual self-control, as explained by Dr. J. William Lloyd:

Karezza [lovemaking without orgasm] is easy and successful just in proportion to the abundance of mutual love - hard and difficult just in proportion as mere sex-craving dominates love. If the woman loves her mate so much that his mere presence, voice, touch, are a heaven of joy to her, so much that the sex-relation is only an adjunct and she could be happy if entirely without it, then, by a sort of paradox, not only does she enjoy it twice as exquisitely as her merely sex-craving sister, but can let it go at any moment without a pang. On the other hand the more the man rises above mere sex-hunger in delicious perfection of romantic love, the more easy and natural and effortless becomes Karezza-control, and the less likely is he to [ejaculate]...

A less-driven, more affectionate, approach benefits us because we stay bonded more easily, granting us the many healthy benefits of trusted companionship (faster healing, increased longevity, better overall health).²² With this alternative approach, dopamine doesn't drop off radically, as it does after orgasm, and generous touch and trusted companionship sustain the production of oxytocin. In short, this other approach to lovemaking protects the neurochemistry that maintains the pair bond.

In the end, the most satisfying sexual encounters occur when we are not making love because we're seeking relief from an uncomfortable withdrawal. Fulfilling lovemaking is a function of an inner sense of abundance (moderate levels of dopamine) and lots of selfless consideration for each other (ideal levels of oxytocin). This state is dependent upon balanced brain chemistry in the reward circuit of the brain - and the self-discipline necessary to maintain it. Only then can we consistently make love with each other's well-being at heart - and elude evolution's tactic of diverging libidos.