This is your brain in love

In a fascinating new book, evolutionary anthropologist Helen Fisher examines the chemistry responsible for the giddiness, fixations and overarching lunacy associated with romantic love.

By Carlene Bauer

Jan 27, 2004 | Claude Lévi-Strauss and Charles Darwin probably never received letters containing such desperate pleas as "Do you think it's possible for someone to fall in love with you after a year of being together ... I would love to hear from you because my heart is just breaking and I don't know what to do." But for evolutionary anthropologist Helen Fisher, who has spent her career writing on the biology behind human intimacy, handling such correspondence is all in a day's work. In her latest book, "Why We Love: The Nature and Chemistry of Romantic Love," Fisher, the author of "The Anatomy of Love" and "The First Sex," examines the brain chemistry responsible for the swooning, stalking and general irrationality associated with romance. She argues that romantic love is a basic human drive like hunger, orchestrated by neurotransmitters and hormones, that evolved to ensure we would find mates suitable enough to raise families with, thereby propagating the species.

According to Fisher, a research professor at Rutgers University, the bliss we feel when we fall in love is the result of elevated levels of dopamine and norepinephrine, which can result in sleeplessness, exhilaration and single-mindedness, among other things, and low levels of serotonin, which can set the mind racing toward obsession. What we're feeling in those early throes of passion is an addiction, she says. Some may think this sounds like a just-so story with footnotes, but there's something comforting in the notion that maybe it's the dopamine talking when it's 2 in the morning and you've been Googling your office crush for the past seven hours.

Fisher is a gamine 58-year-old whose fine-spun blond hair and modulated yet exclamatory manner recall Doris Day -- if Doris Day were a Ph.D. with a penchant for giving no-nonsense advice to the lovelorn, reporters included. Among her tips? Don't think you can fornicate frequently and indiscriminately without, à la "A Midsummer Night's Dream," one day waking up to find you've fallen in love with an ass. And maybe lay off the Prozac.

The big news in this book is an experiment in which you scanned the brains of people in love. And you found differences between men and women.

We weren't even thinking of looking for that. Although I did write a book on gender differences ["The First Sex"], most of what I talk about is the evolution of a brain system that's in everybody. I'm interested in why we're all alike. What we discovered is that the parts of the brain that lit up and became active when someone falls in love are part of the reward system in the brain. And one of them is the ventral tegmental area, a tiny part in the midbrain, quite far down, that makes dopamine and sprinkles it around the brain. When the prefrontal cortex -- the part behind your forehead, the thinking part -- realizes that you are not getting your reward, those dopamine cells work harder and pump out more dopamine and you feel more motivation, more ecstasy, and that's why -- think of Romeo and Juliet -- when there are barriers to the relationship, you try harder and you love harder.

On average, men tended to show more activity in two regions in the brain: One was associated with the integration of visual stimuli and the second was with penile erection. This really shouldn't come as a surprise. Everybody knows that men are highly visual -- men spend their lives commenting on women, looking at porn, and the like. I believe these visual networks evolved 1 or 2 million years ago because men needed to look at a woman and size up her ability to give him healthy babies. If he saw that she was young and healthy and happy, it would be adaptive for him to become aroused to start the mating process. Men definitely fall in love faster than women -- there's good psychological data on that. And I think that's because they are more visual.

And women?

Several regions associated with memory recall became active. And I couldn't figure out why at first, and then I thought to myself, my goodness -- for millions of years women have been looking for someone to help them raise their babies, and in order to do that you really can't look at someone and know whether they're honest or trustworthy or whether they can hit the buffalo in the head and share the meat with you. You've got to remember what they said yesterday, what they said three weeks ago, what they gave your mother two months ago at the midwinter festival. For millions of years women have had the hardest job on earth -- raising tiny helpless babies for as long as 20 years. That is an enormous job. There's no other animal on earth for whom motherhood is so complex. And if their husband died they'd have to expend an enormous amount of metabolic energy to find another one, and they're that much older, and the clock is ticking -- it's an adaptive strategy to remember all these details.

So you're saying this would explain why, a copious amount of undergraduate women's studies notwithstanding, I feel myself turning into Alice Kramden when, during arguments with my boyfriend, I dredge up things he wishes I'd forget?

Women remember. It drives both sexes crazy. If women could forget a few things, it might be better for them. Men complain about their marriages much less than women do; they remarry faster than women do. Throughout their lives women have many more complaints during the marriage. But if men could remember a few things, it would probably be better for them too!

Falling in love seems too unpredictable and individual a process to qualify objectively. How was it possible for you to decide whether someone was sufficiently far gone to use them as a subject?

I established about 20 primary characteristics of romantic love, and I did it several ways. First I went through the last 25 years of psychological literature, looking for the things that come up over and over again. And I looked at poetry from around the world -- from ancient Sumer, China and India [for similarities in the expression of love across time and history]. Other anthropologists use potsherds, arrowheads, all kinds of things, and it just seemed to me that songs and poems are artifacts, too. Then I created a questionnaire, which I gave to 430 Americans and 420 Japanese of all ages. And those candidates who said they were in love responded to the characteristics outlined in the questionnaire in positive ways.

So here are the basic characteristics: You lose a sense of self, your edges become porous -- this person almost invades, but it's a very pleasant invasion. Then there are mood swings -- real giddiness and ecstasy when things are going well, but if you don't hear from him via e-mail or phone, there's despair.

But the main characteristic for me is obsessively thinking about the person. When I was interviewing people to put into the fMRI machine, the first thing I asked them was how long they'd been in love, because I wanted them really crazy -- I wanted them in the beginning stages, because these machines are expensive, they're time-consuming for everybody. So they had to be absolutely nuts. The second question I asked was, what percentage of the day or evening do you think about this person? And I was looking for those who said 85, 90 percent -- as in, I can't stop, she's never out of my mind.

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