The Best Insurance Against Infidelity

October 11, 2010

Though the neuroscience of sexual attraction has only recently become a practical field of study, humans have understood that sex is chemistry for thousands of years. Those fortunate enough to have fallen head over heels in love can attest to the potent cocktail that surges through the bloodstream as they enjoy the heady first stages of requited physical attraction and lust.

Marnia Robinson, author of the book Cupid’s Poisoned Arrow: From Habit to Harmony in Sexual Relationships, has written extensively on the topic of our sex lives, believing that if we understand our biological responses, we have more control over initiating and controlling them. She describes herself as someone who “writes books about the unwelcome effects of evolutionary biology on intimate relationships.” Recently, she penned the article Cupid’s Ammo for The Good Men Project.

“When you’re hit by Cupid’s arrow, you effectively become delusional. You don’t realize this, of course, because, well, you’re delusional. You’re convinced that the person you met last week at your buddy’s wedding is The One, and you expect the passion you’re feeling to keep you quivering with interest and ecstasy for a lifetime.”

Cupid’s “ammo” is the jolt of neurological impulses that kickstarts mating in the mammalian brain. That programming is designed to increase the genetic variety of offspring – the greater the diversity of genes, the better the chance of long-term survival. That set of triggers is rather hostile to monogamy, as it turns out.

“The mammalian brain’s mating agenda urges you to:

(1) fall in love recklessly with fireworks that propel sperm to egg,

(2) bond long enough to fall in love with your kids so they have two caregivers,

(3) get fed up with your mate,

(4) look for a new one.

Cold, heartless, but effective.”

We’re not really designed for monogamy. On the other hand…staying in a successful monogamous relationship confers enormous benefits on all parties, including children:

  • Close, trusted companionship protects psychological and physical health.
  • Having two caregivers improves kids’ chances of well-being.
  • One household is also cheaper to maintain than two.
  • Serial seduction can be downright tiring—and expensive.

Unfortunately, realizing the benefits of monogamy over the long-term isn’t possible if you get fed up with your mate and look for a new one, as the divorce rate demonstrates. Yet maintaining sexual attraction for an extended period is not easily achieved – scientists say that the “honeymoon cocktail” of passion and desire lasts two years max. Even worse, the answer is not just having more sex with lots of orgasms – in fact, that may be counterproductive!

Robinson explains that “Intense sexual stimulation can actually dampen the pleasure response in many brains, at least temporarily. This can be a powerful trigger for a mammal to seek greener pastures.”

Fertilization duty done here; time to find this mate less alluring—and respond to any potential novel mate with gusto.

This natural waning of desire has been dubbed the Coolidge Effect because of an incident between the former President and his wife. In his recent book Decoding Love, Andrew Trees shares the story:

“The first couple were separately touring a government farm. Mrs. Coolidge noticed a rooster mounting a hen and asked how often the rooster copulated. The answer was dozens of times a day, to which she replied, “Please tell that to the president.” When Coolidge was later told about this exchange, he asked if the rooster always mated with the same hen and was informed that the rooster copulated with different hens. Coolidge smiled pleasantly and said, “Tell that to Mrs. Coolidge.””

(As an aside, I’d like to observe that Mrs. Coolidge’s wanting multiple rounds, and Mr. Coolidge’s teasing, sounds like shorthand for an excellent sex life, the Coolidge Effect notwithstanding.)

Experiments with rats have confirmed that dopamine production rises until climax, then subsides. Each subsequent encounter with the same female rate produces a smaller spike, and after several times, it barely rises above normal. It takes a new female rat to produce a strong initial spike again. It is the expectation of a reward, rather than the reward itself, that produces dopamine, and expectation will be highest when the female is still a novelty. The implications for humans are obvious. A woman’s best strategy is to prolong the period of anticipation and expectation as long as possible, thereby increasing her odds of having inspired emotional investment before the highest dopamine spike occurs.

Among long-term couples, the dopamine production is going to level off, and the desire for a new sexual conquest is natural, if not welcome. Robinson believes that the key to staying in love, and keeping the cheating urge at bay, is to actively promote and engage in behaviors that chemically promote bonding.

Since most of us don’t realize that subtle neurochemical shifts are coloring our views, we tend to blame each other. The good news is that the ancient mammalian brain is also home to the only part of the brain that can stay in love. Just as too much sexual stimulation can put lovers out of sync, “attachment cues” can help them look good to each other indefinitely.

Robinson says that bonding behaviors send a message to the unconscious brain to strengthen this emotional tie. They include:

  • Skin-to-skin contact
  • Gazing into each other’s eyes
  • Kissing with lips and tongues
  • Wordless sounds of contentment and pleasure
  • Stroking with intent to comfort
  • Touching and sucking of nipples/breasts
  • Spooning or hugging each other in silence
  • Placing a calming hand on our lover’s genitals
  • Gentle intercourse

These behaviors are not intended to serve as foreplay, as they are not about producing sexual tension or anticipation. They are meant to produce feelings of comfort and love.

While many young readers will feel that they have no need of such advice – they’re still pursuing that chemical cocktail of delusional desire. It seems to me that there are several implications here for new relationships, as well as for casual sexual ones.

1. Anticipation is key.

Both parties are likely to enjoy a higher dopamine surge if they have been in pursuit of a reward that has been challenging to achieve.

2. Getting into a rut where sex is always expected will more rapidly drive down the dopamine rush.

Women should continue to be selective about sex, even with a monogamous partner. Though there’s nothing wrong with having sex to start a good night’s sleep, having rote sex out of habit is not likely to promote bonding. Keep sex special.

3. During casual sex the male will quickly receive the message “My work is done here” before engaging in any of the bonding behaviors that mitigate that message and inspire him to stick around.

4. Women interested in relationships and commitment should carefully evaluate men for their orientation with respect to bonding behaviors.

Many players have learned to feign interest in them, knowing that women are more likely to grant sexual access after being courted with general signs of affection and caring. Though the timeline has accelerated from months to hours in the contemporary sexual marketplace, bonding behaviors are still recognized as important signals of commitment. The longer a woman can observe these behaviors before having sex, the more certain she can be that the man is relationship-oriented.

5.  It’s not uncommon for women to request “just cuddling” on occasion.

If men actively nurture those bonding moments in the relationship, they’re less likely to get requests for bonding instead of sex.

6. Bonding behaviors promote sexual loyalty, as well as trust in one’s partner.

Sex can be wonderful at all ages and stages of a relationship, even after 25 years of marriage. Monogamy is not easy. The sexual relationship evolves and shifts over time, reflecting life’s highs and lows, and there will be times when your relationship is not rewarding in the exact way you want it to be right then.

Good relationships and good sex require strong emotional bonds. Bonding behaviors are our insurance policy against infidelity.