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ove -- a chemical affair
POSTED 28 JAN 2000 What is falling in love? What accounts for the dreamy days, the sleepless nights, the urgent desire satisfied by the lover's simple presence? Whence the bliss, the acceptance, the blind-eyed eagerness to overlook obvious faults?

While we're at it, what maintains the endless devotion of married couples long after the flameout of doe-eyed infatuation? How can they stand living together for half a century?

Can the bond between mother and infant tell us about romantic love?

When will these guys start answering their stupid questions?

Now.

The Why Files has noticed that some scientists have focused on love and attachment as a physiological process rather than poetry. These folks say being in love involves neurologically active chemicals, not just psychologically active words and sexually active bodies. This focus on the process of love is revealing what makes us tick, romantically speaking.

And it's helped probe the way love changes with time. Helen Fisher, an anthropologist who studies love at Rutgers University, sees three phases to the process:

1. Lust: the craze for sex. "Lust evolved to get you out looking for anything," she says.
2. Attraction: the stage of emotional involvement. When attraction goes right, Fisher says, "You're romantic, passionate, elated, giddy, euphoric."
3. Attachment: attraction may evolve into a long-term relationship marked by calm, peace and security. (Okay, it's a bit idealized, but we hope you get the picture).

Lust responds mainly -- in both sexes -- to testosterone, the "male" hormone.

Attraction is marked by high levels of the neurotransmitter dopamine (also activated by cocaine and nicotine), norepinehprine (adrenaline), the heart-pumping hormone used to respond to emergencies, and low levels of serotonin, another major neurotransmitter.

Attachment is associated with oxytocin, a hormone released during childbirth and nursing, and vasopressin, or anti-diuresis hormone. Vasopressin slows the formation of urine, and at high levels, increases pressure in certain blood vessels.

ood news, bad news
Granted, it's enjoyable, but the attraction phase cannot last forever.

According to Anthony Walsh, a professor of criminology at Boise State University, and author of The Science of Love, "We develop a tolerance for the individual who is responsible for turning on the drugs [like dopamine] within us."

But the good news is that after the euphoria of the mating game evaporates, we can finally return to the life we forgot. "We'd get nothing done if we went around like a giggling schoolgirl," Walsh says. Or, we might add, a bumbling schoolboy.

A different set of chemicals takes over as attraction cedes to attachment. Key among them is oxytocin, a hormone released by the hypothalamus gland that helps stimulate the uterus to contract during childbirth, and allows milk to be released during nursing.

Walsh says lots of oxytocin is also found in the blood of men and women during orgasm. To him, this means that the hormone that promotes bonding between mother and infant during nursing does the same thing when adults are intimate.

That makes sense when you consider that nature -- is there a diplomatic way to say it? -- is lazy. Once the hormone and its receptors were invented for one reason, they were appropriated for another, Walsh says. "Mother Nature mimics, capitalizes on what's already going on between mother and infant. Anything that produces joy would be seized on for adult bonding" during the attachment phase. Why? Because the evolutionary job of attachment is to cement couples at least until their vulnerable infants can live independently.

ove sick
Even a journalist is smart enough to realize that the path of love is not always, as the old Chesterfield ads said, so smooth, so satisfying. Rejection is a fact of life, and spurned lovers are as common as cigarette butts in the gutter. Indeed, Fisher says that when Americans were asked these questions:

Have you ever rejected somebody who really loved you?

Have you ever been rejected by somebody you really loved?

BIBLIOGRAPHY
Anatomy of Love: the Natural History of Monogamy, Adultery, and Divorce, Helen Fisher, Norton, 1992.
The First Sex: the Natural Talents of Women and How They Are Changing the World, Helen Fisher, Random House, 1999,
The Science of Love, Anthony Walsh, Prometheus Books, 1999

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