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

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

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

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.”

He’s not ungrateful to see the masterpieces of Michelangelo. It’s just that his personality is primarily dopaminergic: he enjoys anticipation and planning more than doing.

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.

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.

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.

As he heads back into the street, the thought crosses his mind: there’s a big difference between wanting something and liking it.

Why? And so on. The philosopher Aristotle played this same game, but with a more serious purpose. He looked at all the things we do for the sake of something else and wondered if there was an end to it all. Why do you go to work, really? Why do you need to make money? Why do you have to pay bills? Why do you want the electricity to stay on? Where does it end? Is there anything we seek for itself only, not because it leads to something else? Aristotle decided there was. He decided there was a single thing that lay at the end of every string of Whys, and its name was Happiness. Everything we do, ultimately, is for the sake of happiness.

An important memory has been formed: important because it’s linked to survival, important because it was triggered by the release of dopamine. But what happens when dopamine gets out of control?

Dopamine circuits don’t process experience in the real world, only imaginary future possibilities. For many people it’s a letdown. They’re so attached to dopaminergic stimulation that they flee the present and take refuge in the comfortable world of their own imagination. “What will we do tomorrow?” they ask themselves as they chew their food, oblivious to the fact that they’re not even noticing this meal they had so eagerly anticipated. To travel hopefully is better than to arrive is the motto of the dopamine enthusiast.

Distinguishing between what we want and what we like can be difficult, but the disconnect is most dramatic when people become addicted to drugs.

Drugs destroy the delicate balance that the brain needs to function normally. Drugs stimulate dopamine release no matter what kind of situation the user is in. That confuses the brain, and it begins to connect drug use to everything. After a while, the brain becomes convinced that drugs are the answer to all aspects of life. Feel like celebrating? Use drugs. Feeling sad? Use drugs. Hanging out with a friend? Use drugs. Feeling stressed, bored, relaxed, tense, angry, powerful, resentful, tired, energetic? Use drugs. People in twelve-step programs such as Alcoholics Anonymous say that addicts need to watch out for three things that might trigger craving and topple them into relapse: people, places, and things.

There’s no partying there. There’s no enjoyment. This is about relieving the pain. People have this mistaken notion that you get high. What you’re really getting is relief from the low.

When an expected reward fails to materialize, the dopamine system shuts down. In scientific terms, when the dopamine system is at rest, it fires at a leisurely three to five times per second. When it’s excited, it zooms up to twenty to thirty times per second. When an expected reward fails to materialize, the dopamine firing rate drops to zero, and that feels terrible. That’s why a dopamine shutdown makes you feel resentful and deprived. It’s how a recovering drug addict feels every day as he struggles to get clean and sober. It takes an enormous amount of strength, determination, and support to overcome addiction. Don’t mess with dopamine. It hits back hard.

Boosting dopamine can lead to enthusiastic engagement with things that would otherwise be perceived as unimportant. For example, marijuana users have been known to stand in front of a sink, watching water drip from the faucet, captivated by the otherwise mundane sight of the drops falling over and over again. The dopamine-boosting effect is also evident when marijuana smokers get lost in their own thoughts, floating aimlessly through imaginary worlds of their own creation. On the other hand, in some situations marijuana suppresses dopamine, mimicking what H&N molecules tend to do. In that case, activities that would typically be associated with wanting and motivation, such as going to work, studying, or taking a shower, seem less important.

like a man who carries around a rock all day because it feels so good when he puts it down.

Addiction is not a sign of weak character or a lack of willpower. It occurs when the desire circuits get thrown into a pathological state by overstimulation.

The enhanced dopamine circuit boosted impulsive behavior, but not satisfaction—it boosted the wanting, but not the liking.

THE POWER OF EASY ACCESS When it comes to addiction, easy access matters. More people get addicted to cigarettes and alcohol than to heroin, even though heroin hits the brain in a way that is more likely to trigger addiction. Cigarettes and alcohol are a larger public health problem because they are so easy to obtain. In fact, the most effective way to reduce the problems caused by these substances is to make it more difficult to get them. We’ve all seen “quit smoking” advertisements on buses and subways. They don’t work. We’ve heard about school programs that teach kids to say no to drugs and alcohol. In many cases drug and alcohol use go up after these programs because they pique the curiosity of the adolescent students. The only thing that has been shown to work consistently is raising taxes on these products and placing limits on where and when they can be sold. When these measures are taken, use goes down.4 As barriers to the use of tobacco have gone up, barriers to pornography have gone down. In the past, getting sexually explicit pictures was something of an ordeal. People had to muster the courage to walk into a drugstore, pick up a magazine, and then hope the cashier wasn’t a member of the opposite sex. Today, pornographic pictures and videos can be had in seconds and in complete privacy. There are no barriers of embarrassment or shame. We don’t yet know if compulsive viewing of pornography is exactly the same as drug addiction, but they have things in common. As ...

The dopamine desire circuit is powerful. It focuses attention, motivates, and thrills. It has a profound influence over the choices we make. Yet it isn’t all-powerful. Addicts get clean. Dieters lose weight. Sometimes we switch off the TV, get off the couch, and go for a run. What kind of circuit in the brain is powerful enough to oppose dopamine? Dopamine is. Dopamine opposing dopamine. The circuit that opposes the desire circuit might be called the dopamine control circuit.

Dopamine encourages us to maximize our resources by rewarding us when we do so—the act of doing something well, of making our future a better, safer place, gives us a little dopamine “buzz.”

Removing dopamine appeared to diminish a rat’s will to work.

This points us toward an understanding of how dopamine affects the choices we make between working hard or taking the easy way. Sometimes we want a fancy meal, and we’re willing to work hard to prepare it. Other times all we want to do is “veg out”—we’ll tear open a bag of Cheetos in front of the TV, instead of working for even the few minutes it might take to make a simple meal. Consequently, the next step in the experiments was to introduce the element of choice.

The ability to put forth effort is dopaminergic. The quality of that effort can be influenced by any number of other factors, but without dopamine, there is no effort at all.

those who started the drug at the youngest age and took the highest doses were the least likely to develop problems with illicit drugs. Here’s why: if you strengthen the dopamine control circuit, it’s a lot easier to make wise decisions. On the other hand, if effective treatment is withheld, the weakness of the control circuit is not corrected. The desire circuit acts unopposed, increasing the likelihood of high-risk, pleasure-seeking behavior.

After the glow of satisfaction wears off, though, an uncomfortable question comes up: Will I make it next year? All the people who congratulated me—what will they think when my name disappears from the list? No one stays on the list forever; how will I bear the humiliation of being dropped?

dreams are inner representations of inner ideas. Cut off from the senses, dreams allow dopamine to run free, unconstrained by the concrete facts of external reality.

Albert Einstein once said, “My passionate sense of social justice and social responsibility has always contrasted oddly with my pronounced lack of need for direct contact with other human beings.” And “I love Humanity but I hate humans.” The abstract concepts of social justice and humanity came easily, but the concrete experience of encountering another person was too hard.

I love humanity but I hate people. —Edna St. Vincent Millay

One of the variants of the D4 gene is called 7R. People who have the 7R variant tend to be novelty-seeking. They have less tolerance for monotony and pursue whatever is new or unusual. They can be impulsive, exploratory, fickle, excitable, quick-tempered, and extravagant. On the other hand, people with low novelty-seeking personalities are more likely to be reflective, rigid, loyal, stoic, slow-tempered, and frugal.

The hedonistic paradox states that people who seek happiness for themselves will not find it, but people who help others will.

The hedonist believes that his deepest self is the part of him that experiences pleasure. Whether it’s wine, women, or song, his purpose in life is to maximize the rewards he gets when he pursues more. That’s dopamine.

A Harvard study that’s been going on for seventy-four years has found that social isolation (even in the absence of feelings of loneliness) is associated with a 50 to 90 percent higher risk of early death. That’s about the same as smoking, and higher than obesity or lack of exercise. Our brain needs affiliative relationships just to stay alive.