Watchman Newsletter

The Science of Sex

One News Now (Link) - Marcia Segelstein (June 16, 2009)

Thanks to medical science, we now know that smoking cigarettes is unhealthy. It can lead to diseases like emphysema and lung cancer, and increase the risks of heart disease and stroke. So we have acted swiftly on that information. In one generation, our attitude about smoking has undergone a remarkable transformation. Where smoking was once commonplace, and homes everywhere had ashtrays, even if only for visiting smokers, today it's almost shocking to see someone light up. Banned from airplanes, offices and many restaurants, smoking and smokers are viewed with a kind of disdain at worst, pity at best. TV shows and movies rarely show people smoking, except when they're villains. The dangers of smoking are taught to young people with almost religious zeal. Most modern parents who found evidence that their teenagers were smoking would haul them down to the nearest cancer ward for a close up look at the consequences of smoking, or at least to their doctor, who would undoubtedly back up parental warnings that smoking is dangerous to their health.

Now substitute the words "casual sex" for "smoking." Thanks to medical science, we now know that casual sex is unhealthy.

Not just because of the myriad of sexually transmitted diseases it can cause, to say nothing of the unwanted pregnancies it can create, but because of what it does to the human brain.

Two doctors, Joe McIlhaney and Freda McKissic Bush, explain what we now know about sex and the human brain in their book, Hooked: New Science on How Casual Sex Is Affecting Our Children.

Let's start with the brain chemical called dopamine. Dopamine is considered a "reward signal." We now know that when humans do exciting and rewarding things, dopamine floods the brain, producing a feeling of well-being. As the authors write: "It is dopamine that gives us a charge of excitement and rewards us for having the courage to take an action with an uncertain outcome....It should be noted, however, that dopamine is values-neutral. In other words, it is an involuntary response that cannot tell right from wrong, or beneficial from harmful it rewards all kinds of behavior without distinction."

Dopamine can make adolescents feel good about taking both good and bad risks, from being in the high school musical or trying out for a sports team to driving too fast or having sex. Any exciting behavior triggers the release of dopamine, and adolescents in particular want more once they've had some.

Oxytocin is another important brain chemical we are now learning more about. Oxytocin helps females, in particular, bond with other people. When a new mother breastfeeds her infant, for example, oxytocin floods her brain. The effect is powerful. She feels a strong desire to be with her baby, and is willing to suffer the sleepless nights and inconveniences that come with having a baby.

Oxytocin also helps females bond with men. When a woman and man touch each other in a loving way, oxytocin is released in her brain. It makes her want more of that loving touch, and she begins to feel a bond with her partner. Sexual intercourse leads to the release of even more oxytocin, a desire to repeat the contact, and even stronger bonding. But, like dopamine, oxytocin is values-neutral. It's a chemical reaction, or, as the authors write: "[I]t is an involuntary process that cannot distinguish between a one-night stand and a lifelong soul mate. Oxytocin can cause a woman to bond to a man even during what was expected to be a short-term sexual relationship." So when that short-term relationship ends, the emotional fallout can be devastating, thanks to oxytocin.

Another significant finding about oxytocin is that it produces feelings of trust. That can be good or bad, depending on the situation. "While the hormonal effect of oxytocin is ideal for marriage, it can cause problems for the unmarried woman or girl who is approached by a man desiring sex....[T]he warning is that a woman's brain can cause her to be blindsided by a bad relationship that she thought was good because of the physical contact and the oxytocin response it generates."

Males have their own neurochemical related to bonding: vasopressin. It floods the male brain during sexual intercourse, causing him to feel at least partially bonded to every woman with whom he's been intimate. If men begin a pattern of having sex with partner after partner, they risk not developing the ability to form long-term emotional attachment. As McIlhaney and Bush put it: "Their inability to bond after multiple liaisons is almost like tape that loses its stickiness after being applied and removed multiple times."

Now let's add to that new information that neuroscience teaches us about the brain chemistry of sex and bonding some cold, hard facts about how effective birth control really is when it comes to teenagers. The authors of Hooked have compiled the following statistics from various sources:

  • 20 percent of 12- to 18-year-olds using the Pill will become pregnant within six months
  • 20 percent of teens under 18 using condoms will become pregnant within a year
  • 50 percent of female teenagers who live with a boyfriend and use contraception will become pregnant within a year

I recently watched a rerun of House (a TV show about a doctor who uses unconventional methods to diagnose illnesses) and was struck by a brief interaction between the doctor and the parents of the teenage patient, who couldn't speak for himself. The parents assured Dr. House that they knew everything about their son. They were non-judgmental, they explained. The son told them everything. They knew about the time he'd gotten drunk, that he smoked pot, and that he started having sex when he was 16. They were cool. Later House discovers irrefutable proof that the son smokes cigarettes, an activity which turns out to be germane to his illness. When House brings it up with the parents, their reaction verges on hysteria. "But he knows I'd kill him," the father screams.

For those of us unconvinced by moral or religious arguments, it's time to re-order our priorities. Now that we have science behind us, it's time for society to change its collective mind when it comes to sex, just as it did with smoking. Maybe in one generation, we can undergo a transformation when it comes to sex outside of marriage. Maybe TV shows and movies will stop implying that casual sex is no big deal. Maybe we'll begin to teach young people that waiting till marriage is best. Then the dopamine and the oxytocin and the vasopressin can do their jobs of helping to make two people one.

We don't expect our kids to take up smoking. We tell them so in no uncertain terms. We should expect no less when it comes to sex, and we should tell them that also.

The authors of Hooked sum up their findings about premarital sex this way: "[T]hose who abstain from sex until marriage significantly add to their chance for avoiding problems and finding happiness."

Science now backs up what religious traditions have been teaching for generations. Who knew? Oh yeah. Him. †

Science ~ Signs of the Times