From the beginning of humanity, cultures and societies vary in tradition, religion, art, philosophy, and customs. One constant that remains unchanging? The essential need for love and partnership. 

Dr. Helen Fisher explains the drive for love from an anthropological perspective, exploring the science of attraction, heartbreak, rejection, and how our dopamine factories send us on lifelong quests to find “the one.”

HELEN FISHER: No matter what their gods were, what they did for a living, what they wore, the songs they sang, everything varies except love, and everybody loves. So I became convinced that this was a real thing, that we were built somehow to form partnerships. And then the day came when I thought to myself, "Well, then it must be something in the brain."

- [Narrator] The science of romantic love.

- I really began by wondering why we bother to pair up at all. 97% of mammals do not pair up; people do. So I thought that might be quite easy. And I looked at the Demographic Yearbooks of the United Nations, and in every culture in the world, and not only around the world today but historically, traditional societies, hunter-gathering societies, every single culture in the world has some mechanism for people to form some sort of partnership to rear their babies as a team. And so I really started by looking at the Demographic Yearbooks of the United Nations, reading over 90 ethnographic studies of hunter-gatherers and agrarian peoples and herding peoples, et cetera. And I just kept seeing the same pattern. And I remember I was walking along in Greenwich Village; it was about three o'clock on a weekday afternoon, and I suddenly thought to myself, "These three brain systems must have evolved: sex drive, feelings of intense romantic love, and feelings of attachment." I remember even where I was standing. And I thought maybe if I could put people into a brain scanner, I could find the basic brain pathways, the basic brain circuitry of these three basic brain systems. A lot of people have studied the sex drive. I didn't need to study that. We know some of the genes, we know some of the hormones, we know the pathways really. I mean, to some extent certainly. But quite a bit about the sex drive. So I felt that it was more important for me to study romantic love and feelings of attachment. And I focused on romantic love because people really do think it's part of the supernatural. Most people don't kill themselves over an attachment. They kill themselves over romantic love. I mean, it is such a powerful brain system that I thought to myself, "If I can figure out what's happening in the brain, maybe I can help people understand this and, in fact, maybe not even kill themselves when they are rejected." Nobody gets out of love alive. We all suffer. Some people suffer more than others. Some people respond very dramatically, and some people can get over it relatively quickly. But nobody gets out of love alive. We all have disappointments. It's such a powerful brain system. I mean, everywhere in the world. It's very interesting because, you know, I was talking to a man, an anthropologist, who studies the people in China. This was many years ago. And he said, "Oh, the Chinese don't love." Well, he didn't read any of their love poetry. Everywhere in the world, there's poetry and songs and dances and dramas that express love. So he went back to China, and he said to his assistant, who was Chinese, he said, "Well, I mean, in China they don't love." And the assistant broke down, started crying, and said, "I have a woman who doesn't love me. I don't know what I'm gonna do." And that sent him on to studying romantic love in China. And when you look around the world, I mean, the poetry. You know, a lot of anthropologists study potsherds or post holes or arrowheads or all kinds of more sophisticated things. But I really like to read poetry because I think it's a basic artifact of this basic brain system. And it always says the same thing. I remember one poem by a Chinese person, and it was something like this. It was something like, you know, "I cannot bear to put away the bamboo sleeping mat. The night I brought you home, I watched you roll it out." Even the things that a lover touches in your house acquire meaning. The brain acquires meaning to anything that has to do with romance and attachment. It's so profoundly basic to who we are. Because if you don't love and you don't attach, you don't have babies, and you don't send your DNA into tomorrow. And from a Darwinian perspective, you lose. It's very interesting. People don't think that other animals love. I've really looked at a lot of other animals, and they do love. They do form romantic, I call it animal magnetism or animal romance. And you can see a rat suddenly feel a very intense interest in another rat, only lasts for about 30 seconds. In elephants, it lasts for about five days. In foxes, it can last a long time. But most animals don't form a partnership. They feel that intense attraction, animal attraction, animal magnetism. And we now know that that attraction is basically the same brain system as our brain system of feelings of romantic love. So other animals love. Darwin said that other animals love. He even thought that butterflies felt that attraction and that this was sort of, oh, a primordial beginning of this attraction system that became incredibly elaborate in the human animal. But why is it that we bother to pair up? All kinds of other animals feel romance, but it doesn't last very long. In humans, it can last months or years, actually. We've been able to prove that romantic love can last many years. I think that the brain circuitry for human romantic love and feelings of deep attachment evolved probably 4.4 million years ago. Our ancestors were being forced out of the trees. They were gonna have to come down onto the ground because the trees were disappearing and move through very dangerous open grasslands to another group of trees and collect what they could on the ground before they went to eat in a place unmolested by predators. And with the beginning of carrying sticks and stones to protect themselves and food to eat, they began to have to walk on two legs instead of four. Chimpanzees walk on four legs, and they've got their baby on their back. We began to have to walk up on two legs instead of four, which meant that females began to have to carry their babies in their arms instead of on their backs. Now, how is a four-million-year-old female gonna have to carry the equivalent of a 20-pound bowling ball in one arm and sticks and stones in the other and protect and feed herself? She began to need a partner to help protect her while she moved along. And how could a male, four million years ago, protect a whole group of females? He could protect one. And so we went over what I call the monogamy threshold, a threshold in which the female needed a partner to help her raise her baby, at least through infancy. And males needed to protect at least one female with his DNA in her. And, of course, you know, females needed a male who wanted to stick around. Those that didn't stick around didn't have the babies and didn't pass their DNA onto you and me, leaving in the human creature today, both men and women, with a tremendous capacity to fall in love, form a partnership, and raise their children as a team. So the bottom line is, along with that, we began to evolve our human brain pathways for human romantic love and feelings of deep attachment. So I began to believe that if I looked into the brain, I could find the brain circuitry of romantic love. So I assembled a team and began to put people in the scanner. And the issue was how to scan the brain. And what I ended up with is the following protocol or research design. They would look at a picture of their sweetheart that called forth the wonderful feelings of romantic love. And they would also look at a photograph of somebody who called forth no emotions, no positive or negative emotions. The problem with that is when you're madly in love with somebody, your emotions are gonna bleed from one picture to the other. So I had to relax the brain between looking at the neutral, the positive, and the neutral. So I used a very standard psychological distraction task. I would cast on the screen a large number like 4,821, and I would ask them for 30 seconds to look at that photograph, that picture, and that number, and count backwards in increments of seven. Now, even mathematicians take some time to count in increments of seven. It takes all the blood away from brain regions linked with romantic love to brain regions linked with just simply counting backwards. So this way, they would bring a photograph of their sweetheart into the lab. They would bring a neutral photograph, somebody from the office who they barely knew, somebody from the dry cleaners, some past friend of somebody who called forth no positive or negative feelings. So they would look at those two photographs. They would look at their sweetheart, then they would count backwards. Then they would look at the neutral, then they would count backwards. So it was: positive, count back, neutral, count back. A cycle of six times, 12 times, looking at these photographs. That way, we were able to capture through the fMRI machine how you felt when you have experienced that intense feeling of romantic love, what you were doing in the brain when you were counting backwards, and how you felt when you were simply looking at the neutral photograph. And when you put the neutral and the romantic love on top of each other and cancel out what they have in common, you're left with what's going on in the brain when you're madly in love. I'll never forget the first moment that I looked at our data. I felt as if I was looking back to over four million years ago when this brain system evolved. And what we saw was activity in a tiny little factory near the base of the brain called the ventral tegmental area. It's a brain region that actually makes dopamine, a natural stimulant, and gives you that focus, that motivation, the craving, the elation of intense romantic love. And, in fact, I was really surprised. I had thought we would find all kinds of data, oh, linked with the emotions and linked with cognitive thinking processes. We did find data linked with thinking processes and the emotions. But no two people were alike, which is obvious; they'd be thinking about somebody else. But they all showed activity in this little factory near the base of the brain. And I had thought that romantic love was an emotion or a series of emotions, but what it really is is a drive, a basic mating drive that evolved millions of years ago to enable you to focus your mating energy on a single individual and start the mating process. As a matter of fact, we now call it a survival mechanism. The basic brain region that generates the dopamine and gives you that feeling of romantic love lies right next to the factory that orchestrates thirst and hunger. Thirst and hunger keep you alive today. Romantic love enables you to focus your mating energy and drive your DNA into tomorrow. So it's a basic survival mechanism that evolved millions of years ago, came out of nature, came out of other animals that feel it, but nowhere near to that degree. As a matter of fact, I think all three of these brain systems evolved in tandem. The sex drive evolved to get you out there looking for a whole range of partners. I mean, you can have sex with somebody when you're not in love with them. Romantic love evolved to enable you to focus your mating energy on just one at a time. And attachment, that third brain system, evolved to enable you to stick with this person at least long enough to raise a single child through infancy. I was absolutely positive it was not a supernatural event. And so, no, I did not think about that person at that moment. But I have been determined to show the world that this is real. So many people suffer from it. And as a matter of fact, you know, a lot of people came and wanted to talk to me, a lot of journalists, et cetera, after we discovered this data. And I thought to myself at the time, "You know, Helen, this really isn't very important." You know, when you're madly in love with the right person, there's no problem. The real problem is when you've been rejected in love. That's when you turn into a pest, not only for all your friends and family, but it's a dangerous situation. So I thought to myself, "Now what I've got to do is put people into the machine who've been rejected in love. That's where I can make a contribution to humanity." Well, then, my next study was putting people into the brain scanner who had just been rejected in love. That was a lot harder because, you know, before I put people in this brain scanner, you really talk to them for a long time. You've gotta make sure that they are madly in love or that they are rejected in love because these machines are expensive, and it's extremely time-consuming. And I also have to tell them what's gonna go on in the machine. I've got to get them to bring me the correct pictures so it triggers the right response in the brain. So I have long discussions with all of our subjects, our participants, before I put them in the machine. And when you've been rejected in love, one girl didn't show up for the scanning. She had not been out of bed for almost four days. Another person cried so hard in the machine that we couldn't use the data. She moved too much. Another person, after the scanning, came out of the machine and was so angry that he went home and, you know, drank too much. And so I began to realize very early, now I'm playing with something that is so powerful that I began to make sure that I walk with them for a while after the scan was over, that I called them that evening and the following morning to make sure that everything was all right. This is when people kill themselves. This is when people kill somebody else. This is when they stalk. This is when they cry all night. This is when they can slip into clinical depression. So I thought it was an extremely important study. I still think it is. And I was determined to see whether rejection in love was actually an addiction. I had even thought that happy love was an addiction because, you know, when you're madly in love, you'll do the craziest things. And sure enough, I was able to put 15 men and women into the scanner who had just been dumped. I was able to find activity in a lot of brain regions. One brain region is that same basic ventral tegmental area, the VTA, that pumps out the dopamine that gives them the feeling of intense dramatic love. Also found activity in a brain region linked with deep feelings of attachment. You don't stop loving somebody when they've dumped you. I found activity in a brain region linked with pain, with physical pain. It is a brain region that also becomes active when you have a toothache. The difference between a toothache and intense rejection is the toothache goes away after you get to the dentist. And with rejection in love, you can feel that pain for months, maybe sometimes years. But most important, I found activity in three brain regions linked with craving and addiction specifically. And what I was looking for is activity in a brain region called the nucleus accumbens. It's the basic brain region that becomes active when you are addicted to cocaine, heroin, booze, alcohol, cigarettes, gambling, all of the addictions. And so I was able to prove that romantic love when you are rejected is an addiction. It is a love addiction. Then we went back, and we were able to find that people who were madly and happily in love were also addicted. We also found activity in this basic brain region, the nucleus accumbens. So I'm trying to get the world to understand how important this brain system is. You know, it's so interesting, some psychologists, you know, you'll go in and they'll say, "Well, just get rid of him. You know, he beats you up. Just get rid of him." And they don't really realize that this person might not be able to get rid of them. As a matter of fact, I really believe in many of the principles of AA, Alcoholics Anonymous, and I do think that we need to treat this particular addiction as a very special addiction with very special therapies.