The Nature and Chemistry of Romantic Love
Humans have evolved three distinctly different brain systems for mating and reproduction: sex drive, romantic love, and attachment.
Published February 12, 2006
By Adelle Caravanos
You can’t sit still, you can’t sleep, you can’t eat, and the same few thoughts are obsessively repeating in your mind. You may have contracted a strange viral disease or a deadly bacterial infection.
Or, you may be in love.
According to anthropologist Helen Fisher, hyperactivity, insomnia, loss of appetite and obsessive thinking are all symptoms of romantic love. More and more, scientists are gaining an understanding of the biological and chemical mechanisms behind the euphoric feeling of being in love. Fisher, a visiting research professor at Rutgers University and former research associate at the American Museum of Natural History in New York, has written hundreds of articles and published four books on love and sex, including, most recently, Why We Love: The Nature and Chemistry of Romantic Love (Henry Holt, 2004).
A year ago, Fisher was approached by Match.com, an online dating community, to assist in the development of a new relationship website. Fisher, a past chairwoman of The New York Academy of Science’s anthropology section, accepted the role of chief scientific advisor to Chemistry.com, a new website that treats matchmaking as a science.
Love Maps for the Road of Life
Researching the project, Fisher completed questionnaires at various dating websites, and found that they had one thing in common. They all appeared to match by sociological similarities, such as educational level and religiosity, she says. But that’s only half the puzzle. The other half is chemical.
We build an unconscious list of characteristics that we’re looking for in a mate as we grow up — a love map, Fisher says. Fifty percent of your love map is based on social factors, according to Fisher; but the other half is biologically constructed. Meeting another person who fits into your love map can actually trigger your brain circuitry for romantic love.
To effectively match people, Fisher first needed to systematically categorize the objects of her matchmaking. Her 30 years of research into the brain and behavior led her to explore the chemical roots of personality — how much do hormonal levels affect character, and could the understanding of this chemistry predict a successful match?
A Match Made in Hormones
Specific personality traits correlate to increased hormonal activity in the brain, according to Fisher. For example, increased dopamine levels are linked to risk taking, spontaneity and optimism, while high serotonin activity correlates to loyalty, conscientiousness and calmness. A high level of estrogen (in males or females) is associated with imagination, verbal ability and idealism; and testosterone relates to rationality, inventiveness and directness.
Fisher developed four categories that she associated with the personality traits related to these hormones. High levels of dopamine produce the Explorer personality; serotonin yields the Builder; estrogen, the Negotiator; and testosterone, the Director. These four categories became part of the criteria for matchmaking on Chemistry.com.
Who Are You?
Fisher designed an interactive, online test to enable Chemistry.com customers to identify their own levels of each of the four hormones, and thus, the corresponding characteristics.
One question asks users to assess the size of their ring finger in relation to the index finger. According to Fisher, a longer ring finger is a clear sign that a person experienced a rush of testosterone in the womb, due to the amount of androgen, or male hormone, receptors in the fourth finger. This increased amount of testosterone indicates a Director personality.
Another question asks if a person has a tendency to count things around them. Fisher says that people who find themselves involuntarily counting, whether it be steps in a staircase or rosebuds on wallpaper, have been found to have higher levels of dopamine — Explorers.
And you just might be a Negotiator if you experience deja vu frequently. Fisher hypothesizes that the experience of feeling as if you are reliving a particular moment is related to high estrogen levels in the brain.
Nobody Loves You Better
Once your dominant personality is identified, how does Fisher suggest matching you?
Biologically speaking, she would generally match people with high levels of estrogen (Negotiators) with those who have increased levels of testosterone (Directors). In the same way, Fisher says, Explorers with elevated dopamine activity are well-matched with Builders who have increased serotonin activity. The two are balancing each other out, and the personalities not only fall in love, but stay in love, because they’re enough different from each other to remain mysterious and attractive, she says.
This sort of chemistry is backed up by evolution, Fisher says. It is adaptive to find a partner who is not exactly like you so you can create more genetic variety in your young, Fisher explains. We’re drawn to these other personality types for good Darwinian reasons.
She cites as an example the sweaty t-shirt experiment in which women asked to select from a number of worn men’s shirts chose those worn by men with immune systems that differed from their own. In theory, the mating of two individuals with very different immune systems will produce more viable offspring.
Similarly, Fisher notes that people are drawn to potential partners who have different, but complementary, dopamine, serotonin, estrogen and testosterone systems. This way, they can pool both their genetic and psychological resources to not only bear but also jointly raise healthy children.
Even if you don’t want to have children, says Fisher, we still have these ancient unconscious strategies for mating.
The Evolution of Love
Humans have evolved three distinctly different brain systems for mating and reproduction, according to Fisher — sex drive, romantic love, and attachment.
She believes that the sex drive evolved to motivate individuals to look at a whole range of partners. Romantic love — the obsessive fascination and elation associated with the early part of a relationship — developed to enable a person to focus mating energy on one partner at a time, thereby conserving time and energy.
Attachment, or the feeling of comfort and security that develops in long-term relationships, evolved to enable an individual to tolerate that person long enough to rear a child together, as a team, according to Fisher.
Fisher is not convinced that romantic love is evolutionarily designed to last forever. Once a couple was expecting a child, it would’ve been much more adaptive to move into the attachment phase, to raise children in a more calm, stable, rational state, Fisher says. Romantic love is not rational, it’s an enormous energy expenditure that is metabolically expensive. You’re walking all night, talking till dawn — we’d all die of sexual exhaustion, if romantic love lasted continually.
Till Death Do Us Part
Then does evolution dictate that romantic love always dies out?
Fisher cited the studies of Elaine Hatfield, who found that people in good, long-term relationships reported not only a deep sense of attachment to their partners, but also low-grade feelings of romantic love. This emotion comes back, at various times when a couple is on vacation, before or after they make love, even when one partner says something funny.
According to Fisher, there are two keys to making love last.
First, couples need to do new things together — novelty and variety has been shown to drive up the activity of dopamine and norepinephrine, both chemicals that are associated with feelings of romantic love. Go swimming after dark, go to a different restaurant for dinner, says Fisher. Even the smallest change of pace can reignite passion.
Second, and more obviously, according to Fisher, it’s important to pick the right person from the get-go. The chemistry between two people is what causes the feeling of romantic love in the first place, and helps to keep it percolating.
And if you’ve ever worried that overanalyzing the euphoria that your lover inspires will somehow diminish it, Fisher offers some reassurance.
You can know all the chemistry involved in a piece of chocolate cake, says Fisher, and still eat that cake and get that intense rush of joy. Similarly, you can learn all there is to know about love, she says, and still feel the madness.
