The Molecule of More: How a Single Chemical in Your Brain Drives Love, Sex, and Creativity―and Will Determine the Fate of the Human Race

by Daniel Z. Lieberman

In your brain the down world is managed by a handful of chemicals—neurotransmitters, they’re called—that let you experience satisfaction and enjoy whatever you have in the here and now. But when you turn your attention to the world of up, your brain relies on a different chemical—a single molecule—that not only allows you to move beyond the realm of what’s at your fingertips, but also motivates you to pursue, to control, and to possess the world beyond your immediate grasp. It drives you to seek out those things far away, both physical things and things you cannot see, such as knowledge, love, and power. Whether it’s reaching across the table for the salt shaker, flying to the moon in a spaceship, or worshipping a god beyond space and time, this chemical gives us command over every distance, whether geographical or intellectual.

Those down chemicals—call them the Here & Nows—allow you to experience what’s in front of you. They enable you to savor and enjoy, or perhaps to fight or run away, right now. The up chemical is different. It makes you desire what you don’t yet have, and drives you to seek new things. It rewards you when you obey it, and makes you suffer when you don’t. It is the source of creativity and, further along the spectrum, madness; it is the key to addiction and the path to recovery; it is the bit of biology that makes an ambitious executive sacrifice everything in pursuit of success, that makes successful actors and entrepreneurs and artists keep working long after they have all the money and fame they ever dreamed of; and that makes a satisfied husband or wife risk everything for the thrill of someone else. It is the source of the undeniable itch that drives scientists to find explanations and philosophers to find order, reason, and meaning.

It is why we look into the sky for redemption and God; it is why heaven is above and earth is below. It is fuel for the motor of our dreams; it is the source of our despair when we fail. It is why we seek and succeed; it is why we discov...

To your brain, this single molecule is the ultimate multipurpose device, urging us, through thousands of neurochemical processes, to move beyond the pleasure of just being, into exploring the universe of possibilities that come when we imagine. Mammals, reptiles, birds, and fish all have this chemical inside their brains, but no creature has more of it than a human being. It is a blessing and a curse, a motivation and a reward. Carbon, hydrogen, oxygen, plus a single nitrogen ...

Love is a need, a craving, a drive to seek life’s greatest prize. —Helen Fisher, biological anthropologist

Only 0.0005 percent of brain cells produce dopamine—one in two million—yet these cells appeared to exert an outsized influence on behavior. Research participants experienced feelings of pleasure when they turned dopamine on, and went to great lengths to trigger the activation of these rare cells. In fact, under the right circumstances, pursuit of feel-good dopamine activation became impossible to resist. Some scientists christened dopamine the pleasure molecule, and the pathway that dopamine-producing cells take through the brain was named the reward circuit.

Dopamine, they discovered, isn’t about pleasure at all. Dopamine delivers a feeling much more influential. Understanding dopamine turns out to be the key to explaining and even predicting behavior across a spectacular range of human endeavors: creating art, literature, and music; seeking success; discovering new worlds and new laws of nature; thinking about God—and falling in love.

Wolfram Schultz

dopamine activity is not a marker of pleasure. It is a reaction to the unexpected—to possibility and anticipation.

Why does love fade? Our brains are programmed to crave the unexpected and thus to look to the future, where every exciting possibility begins. But when anything, including love, becomes familiar, that excitement slips away, and new things draw our attention.

reward prediction error,

We constantly make predictions about what’s coming next, from what time we can leave work, to how much money we expect to find when we check our balance at the ATM. When what happens is better than what we expect, it is literally an error in our forecast of the future: Maybe we get to leave work early, or we find a hundred dollars more in checking than we expected. That happy error is what launches dopamine into action. It’s not the extra time or the extra money themselves. It’s the thrill of the unexpected good news.

That happy error is what launches dopamine into action. It’s not the extra time or the extra money themselves. It’s the t...

That’s dopamine taking charge, and it produces a feeling different from enjoying how something tastes, feels, or looks. It’s the pleasure of anticipation—the possibility of something unfamiliar and better. You’re excited about the bakery, yet you haven’t eaten any of their pastries, sampled any of their coffee, or even seen how it looks inside.

Yet sometimes when we get the things we want, it’s not as pleasant as we expect. Dopaminergic excitement (that is, the thrill of anticipation) doesn’t last forever, because eventually the future becomes the present. The thrilling mystery of the unknown becomes the boring familiarity of the everyday, at which point dopamine’s job is done, and the letdown sets in. The coffee and croissants were so good, you made that bakery your regular breakfast stop. But after a few weeks, “the best coffee and croissant in the city” became the same old breakfast.

When things become part of the daily routine, there is no more reward prediction error, and dopamine is no longer triggered to give you those feelings of excitement.

John Douglas Pettigrew,

the brain manages the external world by dividing it into separate regions, the peripersonal and the extrapersonal—basically, near and far. Peripersonal space includes whatever is in arm’s reach; things you can control right now by using your hands. This is the world of what’s real, right now. Extrapersonal space refers to everything else—whatever you can’t touch unless you move beyond your arm’s reach, whether it’s three feet or three million miles away. This is the realm of possibility.

since moving from one place to another takes time, any interaction in the extrapersonal space must occur in the future. Or, to put it another way, distance is linked to time.

This is the defining characteristic of things in the extrapersonal space: to get them requires effort, time, and in many cases, planning. By contrast, anything in the peripersonal space can be experienced in the here and now. Those experiences are immediate. We touch, taste, hold, and squeeze; we feel happiness, sadness, anger, and joy.

the brain works one way in the peripersonal space and another way in the extrapersonal space. If you were designing the human mind, it makes sense that you would create a brain that distinguishes between things in this way, one system for what you have and another for what you don’t.

The division is so fundamental that separate pathways and chemicals evolved in the brain to handle peripersonal and extrapersonal space.

when the brain is engaged with the extrapersonal space, one chemical exercises more control than all the others, the chemical associated with anticipation and possibility: dopamine. Things in the distance, things we don’t have yet, cannot be used or consumed, only desired. Dopamine has a very specific job: maximizing resources that will be available to us in the future; the pursuit of better things.

Dopamine has a very specific job: maximizing resources that will be available to us in the future; the pursuit of better things.

Love must shift from an extrapersonal experience to a peripersonal one—from pursuit to possession; from something we anticipate to something we have to take care of. These are vastly different skills, which is why over time the nature of love has to change—and why, for so many people, love fades away at the end of the dopamine thrill we call romance.

Glamour creates desires that cannot be fulfilled because they are desires for things that exist only in the imagination. Whether it’s an airplane in the sky, a movie star in Hollywood, or a distant mountain, only things that are out of reach can be glamorous; only things that are unreal. Glamour is a lie.

Picture the busy floor of a casino with a crowded blackjack table, a high-stakes poker game, and a spinning roulette wheel. It’s the epitome of Vegas glitz, but casino operators know that these high-roller games are not where the biggest profits are made. Those come from the lowly slot machine, beloved by tourists, retirees, and workaday gamblers who drop in daily for a few hours alone with flashing lights, ringing bells, and clicking wheels. The modern standard for casino design is to dedicate a whopping 80 percent of floor space to slot machines, and for good reason: slot machines bring in the majority of casino gambling revenue.

Scientific Games.

Then Skinner tried something different. He set up an experiment in which the number of presses needed to release a pellet changed randomly. Now the pigeon never knew when the food would come. Every reward was unexpected. The birds became excited. They pecked faster. Something was spurring them on to greater efforts. Dopamine, the molecule of surprise, had been harnessed, and the scientific foundation of the slot machine was born.

When it comes to love, the loss of passionate romance will always happen eventually, and then comes a choice. We can transition to a love that’s fed by a day-to-day appreciation of that other person in the here and now, or we can end the relationship and go in search of another roller coaster ride. Choosing the dopaminergic kick takes little effort, but it ends fast, like the pleasure of eating a Twinkie. Love that lasts shifts the emphasis from anticipation to experience; from the fantasy of anything being possible to engagement with reality and all its imperfections. The transition is difficult, and when the world presents an easy way out of a difficult task, we tend to take it. That’s why, when the dopamine firing of early romance ends, many relationships end, too.

If Sir Mick chases satisfaction another half century, he still won’t catch it. His idea of satisfaction is not satisfaction at all. It’s pursuit, which is driven by dopamine, the molecule that cultivates perpetual dissatisfaction. After he beds a lover, his immediate goal will be to find another.

From dopamine’s point of view, having things is uninteresting. It’s only getting things that matters. If you live under a bridge, dopamine makes you want a tent. If you live in a tent, dopamine makes you want a house. If you live in the most expensive mansion in the world, dopamine makes you want a castle on the moon. Dopamine has no standard for good, and seeks no finish line. The dopamine circuits in the brain can be stimulated only by the possibility of whatever is shiny and new, never mind how perfect things are at the moment. The dopamine motto is “More.”

Dopamine isn’t the pleasure molecule, after all. It’s the anticipation molecule. To enjoy the things we have, as opposed to the things that are only possible, our brains must transition from future-oriented dopamine to present-oriented chemicals, a collection of neurotransmitters we call the Here and Now molecules, or the H&Ns. Most people have heard of the H&Ns. They include serotonin, oxytocin, endorphins (your brain’s version of morphine), and a class of chemicals called endocannabinoids (your brain’s version of marijuana).

though dopamine and H&N circuits can work together, under most circumstances they counter each other. When H&N circuits are activated, we are prompted to experience the real world around us, and dopamine is suppressed; when dopamine circuits are activated, we move into a future of possibilities, and H&Ns are suppressed.

It’s not easy to say farewell to the dopaminergic thrill of new partners and passionate longing, but the ability to do so is a sign of maturity, and a step toward long-lasting happiness.

Lovers experience the same disconnect between anticipation and experience. The early part, passionate love, is dopaminergic—exhilarating, idealized, curious, future looking. The later part, companionate love, is H&N focused—satisfying, peaceful, and experienced through bodily senses and emotions.

Just as dopamine is the molecule of obsessive yearning, the chemicals most associated with long-term relationships are oxytocin and vasopressin. Oxytocin is more active in women and vasopressin in men.

when scientists injected oxytocin into the brains of female prairie voles, the animals formed a long-term bond with whatever male happened to be around. Similarly, when male voles that were genetically programmed to be promiscuous were given a gene that boosted vasopressin, they mated with one female exclusively, even though other receptive females were available. Vasopressin acted like a “good-husband hormone.” Dopamine does the opposite. Human beings who have genes that produce high levels of dopamine have the highest number of sexual partners and the lowest age of first sexual intercourse.

Most couples have sex less frequently as obsessive dopaminergic love evolves into companionate H&N love. This makes sense, since oxytocin and vasopressin suppress the release of testosterone. In a similar way, testosterone suppresses the release of oxytocin and vasopressin, which helps explain why men with naturally high quantities of testosterone in their blood are less likely to marry. Similarly, single men have more testosterone than married men. And if a man’s marriage becomes unstable, his vasopressin falls, and his testosterone goes up.

Testosterone drives sexual desire in both men and women.

On average, women have the highest levels of testosterone on days thirteen and fourteen of their menstrual cycle. That’s when the egg is released from the ovary, and they are most likely to get pregnant. There are also random variations from day to day and even within a day. Some women produce more testosterone in the morning, others later in the day.

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 hormone 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.

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.

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.

Dopamine can always send us chasing phantoms.

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 intensity 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.

Testosterone and dopamine have a special relationship. 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 passionate love. Therefore, denying sexual satisfaction actually enhances passion—

Dopamine got the nickname “the pleasure molecule” based on experiments with addictive drugs. The drugs lit up dopamine circuits, and test participants experienced euphoria. It seemed simple until studies done with natural rewards—food, for example—found that only unexpected rewards triggered dopamine release. Dopamine responded not to reward, but to reward prediction error: the actual reward minus the expected reward.

the passionate love can be transformed into something more enduring. It can become companionate love, which may not thrill the way dopamine does, but has the power to deliver happiness—long-term happiness based on H&N neurotransmitters such as oxytocin, vasopressin, and endorphin. It’s like our favorite old haunts—restaurants, shops, even cities. Our affection for them comes from taking pleasure in the familiar ambience: the real, physical nature of the place. We enjoy the familiar not for what it could become, but for what it is. That is the only stable basis for a long-term, satisfying relationship. Dopamine, the neurotransmitter whose purpose is to maximize future rewards, starts us down the road to love. It revs our desires, illuminates our imagination, and draws us into a relationship on an incandescent promise. But when it comes to love, dopamine is a place to begin, not to finish. It can never be satisfied. Dopamine can only say, “More.”