The Molecule of More

Shawn wiped a clear space in the steamed-over bathroom mirror, ran his 
fingers through his black hair, smiled. “This’ll work,” he said. 
“Wait. Hold still,” said Samantha. She swept a lock off his forehead. 
“This’ll make you look so handsome.”
“And then . . .”
“Down, boy,” said Samantha, and she gave him a peck on the cheek.
DOPAMINE GETS YOU INTO BED . . . 
AND THEN GETS IN THE WAY
From eager anticipation to the physical pleasures of intimacy, the stages 
of sex recapitulate the stages of love: sex is love on fast forward. Sex 
begins with desire, a dopaminergic phenomenon driven by the hor-
mone testosterone. It continues with arousal, another forward-looking, 
dopaminergic experience. As physical contact begins, the brain shifts 
control to the H&Ns to deliver the pleasure of the sensory experience, 
mainly with the release of endorphins. The consummation of the act, 
orgasm, is almost entirely a here-and-now experience, with endorphins 
and other H&N neurotransmitters working together to shut down 
dopamine.

---

21
LOVE
This transition was caught on camera when men and women in 
the Netherlands were placed in brain scanners and then stimulated 
to orgasm. The scans showed that sexual climax was associated with 
decreased activation throughout the prefrontal cortex, a dopaminer-
gic part of the brain responsible for placing deliberate restrictions on 
behavior. The relaxation of control allowed the activation of H&N cir-
cuits necessary for sexual climax. It didn’t matter whether the person 
being tested was a man or a woman. With few exceptions the brain’s 
response to orgasm was the same: dopamine off, H&N on.
That’s how it’s supposed to be. But just as some people have dif-
ficulty moving from passionate love to companionate love, it can be 
also be difficult for dopamine-driven people to let the H&Ns take over 
during sex. That is, highly driven women and men sometimes find it a 
significant challenge to turn off their thoughts and just experience the 
sensations of intimacy—to think less and feel more.
While H&N neurotransmitters let us experience reality—and reality 
during sex is intense—dopamine floats above reality. It is always able to 
conjure up something better. To add to its seduction, it puts us in control 
of that alternate reality. That these imagined worlds may be impossible 
doesn’t matter. Dopamine can always send us chasing phantoms.
Sexual encounters, especially those within ongoing relationships, 
fall prey to these dopamine phantoms all the time. A survey of 141 
women found that 65 percent of them daydreamed during intercourse 
about being with another person or even doing something completely 
different. Other studies have put the figure as high as 92 percent. Men 
daydream during sex about as much as women, and the more sex both 
men and women have, the more likely they are to daydream.
It is ironic that brain circuits that give us the energy and motivation 
we need to get ourselves into bed with a desirable partner subsequently 
get in the way of our enjoying the fun. Part of it may involve the inten-
sity of the experience. Sex for the first time is more intense than sex 
for the hundredth time—especially sex for the hundredth time with 
the same partner. But the climax of the experience, orgasm, is almost 
always intense enough to move even the most detached dreamer into 
the immediate world of H&N.

---

22
THE MOLECULE OF MORE
WHY MOM WANTS YOU TO WAIT 
UNTIL YOU’RE MARRIED
Though changes in culture have made the attitude passé in 
some quarters, there are still a lot of mothers (and anxious 
fathers) who encourage their daughters to “save themselves 
for marriage.” This is often a part of a larger moral or reli-
gious teaching, but is there any advantage to waiting that is 
based in brain chemistry?
Testosterone and dopamine have a special relation-
ship. During passionate love, testosterone is the one H&N 
that is not suppressed in favor of dopamine. In fact, they 
work together to form a feedback loop—a perpetual motion 
machine that enhances our feelings of romance. Passionate 
love usually increases the desire to have sex. Testosterone 
revs up that desire. Increased desire in turn increases pas-
sionate love. Therefore, 
denying
sexual satisfaction actually 
enhances passion—not necessarily forever, of course, and 
not without significant sacrifice, but the effect is real. Thus 
we find a chemical explanation that, long ago, may have 
been at least part of the basis for behavior we see today. 
Waiting prolongs the most exciting phase of love. The bit-
tersweet feelings of distance and denial are the business 
end of a chemical reaction. 
Passion deferred is passion sustained. If mom wants her 
daughter to get married, amplifying the passion is a good 
way to help things along. Dopamine tends to shut down 
once fantasy becomes reality, and dopamine is the driving 
chemical of romantic love. So what would raise dopamine 
more: agreeing to sex now, or keeping it in the future? Mom 
knows the answer, even if we’re only now learning why. 

---

23
LOVE