Ever fall in love with total abandon, experience mind-boggling sex, been sure you wanted to stay together forever -- and then notice recurring emotional friction arising? Does one of you sometimes becomes clingy or demanding while the other feels devoured and needs "space?"
This misery isn't necessarily due to bad luck or personality quirks. Quite possibly it's coming from an ancient genetic program running in a primitive part of your brain. It becomes more evident after lovers' initial booster shot of honeymoon neurochemistry wears off, so new lovers firmly believe they are immune -- as do people who aren't getting enough loving.
Consider what happens when you drop a male rat into a cage with a receptive female rat. First, there's a frenzy of copulation. Eventually, the fireworks stop. As a result of his changed body chemistry, he now finds her uninteresting. However, if a new female shows up, his exhaustion will miraculously fade long enough for him to gallantly attempt his fertilization duties.
His renewable virility is not indicative of an insatiable libido. Nor does it increase his well-being -- although it may look (and temporarily feel to him) that way. His behavior correlates with surges of neurochemicals in his brain, which command him to leave no female unfertilized (the "Coolidge Effect"). Surging dopamine (the "I gotta have it!" substance) is a "Yes!" Dropping dopamine -- as copulation with a familiar mate continues -- says, "Okay...I'm done."
Dopamine naturally drops after orgasm, which plays right into this phenomenon. Incidentally, this tendency for "fertilization frenzy" to move us toward novel partners is not confined to males. Female rodents have been seen flirting a lot more -- arching in inviting displays -- with unfamiliar partners than with those with which they've already copulated.
Does a variation of the Coolidge Effect show up in human behavior? "I quit counting at 350 lovers," confessed a man from Los Angeles, "and I guess there must be something terribly wrong with me because I always lost interest in them sexually so quickly. Some of those women are really beautiful, too." At the time of our chat his third wife had just left him for a Frenchman and he was discouraged. She had lost interest in him.
Porn-using introverts are as much puppets of this subconscious drive as Italy's President Berlusconi or South Carolina's Governor Sanford. Whether someone attempts to fertilize a hot babe or a two-dimensional image, his genes are cracking the whip. Consider this man's words:
I watched a documentary on guys with extremely expensive "love dolls." One guy had so many that he was running out of room in his home. Even though these were dolls, he had already started to see them as girls he had spent enough time with. Probably why guys collect so much porn....I thought I was amassing some wonderful database of pleasure. But I can't remember ever actually going back. The compelling part is the NEW image, the novel image...the novel love doll.
Why would biology cause a regular partner to look like cold oatmeal and a new one to look like rich chocolate mousse? So more offspring with greater genetic diversity are produced (on average across populations). Your genes prefer to sail into the future on as many different boats as they can clamber aboard. Monogamy is as risky as putting all eggs in one basket.
Want proof? No mammals are monogamous (in the sense of being sexually exclusive), and only three percent even bother pair bonding. These pair-bonding outliers (including humans) are known as socially monogamous. They readily form long-term attachments and often raise their offspring together, but they frequently stray. It's the same for swans and other lovebirds.
Even if spouses manage to stay faithful, this neurochemically induced dissatisfaction can push them out of sync sexually, or make them see each other like another serving of "Hamburger Helper." Indeed, research shows that spouses tend to find each other more irritating the longer they are married.
Some couples attempt to fool the brain that a new mating opportunity has arrived by viewing porn, or acting out sexual fantasies. Others swap mates or raise their dopamine by generating intense feelings (as with bondage). However, it can be exhausting to have to orchestrate an adequate dopamine surge every time you want to make love. Indeed, the more intensely you stimulate each other, the more tolerance tends to increase, which means more and more stimulation is needed. And what happens when one partner wants a "fix" of sexual excitement and the other is not ready to invest so much effort, or run the proposed risk, to get a thrill? The more frequently and intensely we attempt to satiate each other sexually, the more restless many of us are likely to grow.
But what if couples want to stay together rather than serve strictly as prime "gene machines?" Fortunately, there are ways to expand our lovemaking repertoire with techniques that stave off habituation effortlessly. Next post: "Staying in Love the Lazy Way."
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