Scientists can only measure so much of the one thing we long for most

By Raj Kaushik / Special to The Sunday Herald

'IT'S THE BEST thing that's ever happened to me. There is a kind of sparkling chemistry between us."

They kiss, cuddle and show off their love amid the shower of camera flashes. It is not unusual when you hear the same person saying after a while, "Last time I was young and naпve. This time it is real."

Strange but true, some people, like Hollywood queen Elizabeth Taylor, repeatedly get hooked up with the wrong person and make a mockery of love.

There are also people who really do understand the depth of love. Some people do not even dream of a person other than their spouses.

What is Love? In some cases love vanishes in no time, while in others it appears to decay with time like a radioactive curve, and in still others love blossoms and seems to imitate our universe, which expands relentlessly.

In extreme cases, love can also turn into obsession or even hatred.

For centuries, love has been considered a mystical phenomenon. It's associated with the mind, heart, body and soul. Now scientists are trying to understand its nature and complexities.

In the mid-1960s, psychologist Dorothy Tennov surveyed 400 people about what it's like to be in love. Many of her respondents talked about fear, shaking, flushing, weakness, and stammering. Indeed, when human beings are attracted to one another, it sets off quite a chain reaction in the body and brain.

There's a lot more going on in a body that's in love than simply sweaty palms or faster heartbeat or happy thoughts. Humans produce over 30 hormones in various organs called endocrine glands, as well as in the brain and kidneys. Without hormones our bodies wouldn't grow or mature sexually.

Hormones actually cause our hearts to speed up under stress, and help the body convert food into energy. In fact, recent studies have focused on exactly what kind of chemical and brain activities occur at different stages of human courtships.

Stage one: Fantasy Fairy tales have always been an integral part of our childhoods. Girls dream about boys (think of the prince who appears in most fairy tales) with slightly feminized faces because they appear warmer, kinder and trustworthier.

Long before personals columns, long before Internet dating, we relied on our own perceptions and construct a fantasy around the information we perceive and collect. Even when we aren't in love, imagining about being in love arouses us emotionally and sexually.

In the early 1970s, Dr. Julie Heiman, a psychologist at the University of Washington, asked college students to wear a tampon-like device that detected blood flow to the vagina. While they wore it, young women listened to romantic tape recordings and to erotic ones. In this study, women, like men, were found to be more aroused by erotic tapes than romantic ones.

Today, websurfers often engage in erotic chats and experience sexual and emotional arousal without seeing, touching, smelling and cuddling a person at the other end.

Take Mike, for example, a typical computer geek. He is in love with a girl whom he has never met. But whenever Mike thinks of her, he feels elevated. Having a strong sense of pleasure by daydreaming is the beginning of love.

Stage two: Lust

In the past few decades, scientists have discovered chemicals and hormones that are triggered when we're attracted to someone. They now know that for both men and women it's a combination of testosterone - a hormone that triggers our sex drive - and neurotransmitters in the brain that boost our heart rate, blood pressure and sweat production. During puberty, testosterone levels are at their lifetime peak.

This release of testosterone is what gets Mike out the door looking for a partner. One day while window-shopping, Mike suddenly catches a glimpse of Carolyn. She is the princess of his dreams.

Mike's hypothalamus - the brain region that triggers the chemicals responsible for emotion - tells his body to send out attraction signals: his pupils dilate; his heart pumps harder so that his face flushes; he sweats slightly, which gives his skin a warm glow; glands in his scalp release oil to create an extra shine to his hair.

In the night, Mike does not sleep properly. Carolyn's heart-shaped face, small at the jaw with wide eyes, directs his brain to secrete increasing levels of dopamine, creating an intense desire to meet Carolyn. Scientists say it's partly the dopamine that makes us crave being with someone special.

Next morning, Mike waits for Carolyn near her home. As Carolyn comes out of her lane, Mike approaches her, excreting his pheromones in the air. Carolyn sounds excited when Mike greets her. Unlike hormones that circulate in an individual's bloodstream, a pheromone molecule acts at a distance from the person who excretes it and has an effect on another person.

When they meet the next night at a restaurant, Mike's stomach flip-flops and he starts feeling giddy at the sight of her. His brain pathways become intoxicated with elevated levels of dopamine, norepinephrine (another neurotransmitter) and particularly phenylethylamine (PEA).

This cocktail of natural chemicals gives Mike a slight buzz, as if he had taken a very low dose of amphetamines (or a large dose of chocolate, another source of PEA). PEA contributes to that almost irrational, on-top-of-the-world feeling that attraction can create. It gives Mike the energy to stay up all night talking to Carolyn.

Stage three: Romance

A recent study done at Emory University shows that female voles (small rodents) choose their mates in response to dopamine being released in their brains. When injected with dopamine in a male vole's presence, the female will pick him out of a crowd later. Chocolate also elevates levels of dopamine in the brain.

Norepinephrine, a euphoria-inducing chemical in the brain, stimulates the production of adrenaline and makes Mike's blood pressure soar when he makes romantic moves on Carolyn.

As Mike is falling in love, his brain produces higher levels of serotonin. Serotonin is closely associated with the control of moods, which can fluctuate drastically in the journey of love. Serotonin's role in romance is still not fully understood, but it can have a calming effect on people.

To be timeless and boundless, love requires time and space. Scientists estimate that PEA is typically released for 18 months to 4 years. They believe that after this period one's body gets used to this love stimulant.

At this stage Mike's love may either lose its charm and grace, or may cool into what Helen Fisher, author of Anatomy of Love, calls "attachment."

Stage four: Attachment Our brain's hypothalamus controls "primitive" behaviours such as sex, aggression, and feeding. It produces the two hormones vasopressin and oxytocin. Derived from the Greek for swift birth, oxytocin is also known as the cuddle chemical.

The Nobel-prize work of Vincent du Vigneaud in 1953 pioneered the synthesis of oxytocin and vasopressin.

Dopamine stimulates the production of oxytocin. Scientists have known since 1906 that oxytocin stimulates human female contractions during childbirth.

It blunts the physical pain of childbirth and induces sensations of pleasure. The role of oxytocin in males is not known yet.

Oxytocin's romantic power was first recognized in 1979 when virgin male rats whose brains were injected with the hormone began to display maternal behaviour. Several research studies have shed light on oxytocin's role in the early stages of sexual passion and in the process of bonding beyond birth.

In a preliminary study published in the July 1999 issue of Psychiatry, oxytocin is shown to be associated with the ability to maintain healthy interpersonal relationships and healthy psychological boundaries with other people.

Both men and women release oxytocin at the moment of sexual orgasm, suggesting that it might be involved in strengthening the bond between couples. A sense of belonging brings further increases in oxytocin, which may suggest why some couples would long to be together in life and death.

Love is Life

"When you feel loved, nurtured, cared for, supported, and intimate, you are much more likely to be happier and healthier. You have a much lower risk of getting sick and, if you do, a much greater chance of surviving," Dean Ornish concludes in his book, Love and Survival, the Scientific Basis for the Healing Power of Intimacy (HarperCollins, 1998).

In a similar vein, a 10-year study by doctors at the Royal Edinburgh Hospital in Scotland suggests that chemicals produced during sex enhance mind and check the aging process.

The science of love is important in understanding its real depth. But most scientists believe that this area is in its infancy. We are still performing experiments on monkeys and rodents. Obviously, the findings of these experiments are not directly applicable to humans.

Most scientists would also agree that science involved in love can't explain everything. Culture, ethnic, religious and educational backgrounds, personality, and scores of other variables would also have significant influence in shaping the course and meaning of love.

Love is essential for life.

"Love alone is capable of uniting living beings in such a way as to complete and fulfill them, for it alone takes them and joins them by what is deepest in themselves," said Pierre Teilhard de Chardin, a visionary French Jesuit, paleontologist, biologist, and philosopher.

Former Halifax resident Raj Kaushik now works in Toronto.