Will You Be My Valentine? The Answer, Says An Expert, Depends on Brain Chemistry

updated 02/21/1983 AT 01:00 AM EST

originally published 02/21/1983 AT 01:00 AM EST

What is this thing called love? Increased levels of phenylethylamine, perhaps? A response to endorphins by our presynaptic receptors? Dr. Michael R. Liebowitz, who directs the Anxiety Disorders Clinic at the New York State Psychiatric Institute, believes that falling in love, suffering in a lover's absence, growing restive as romance fades—all appear to be influenced by our brain chemistry. The search for connections between emotional states and body functions—called psychobiology—is the focus of Dr. Liebowitz's book The Chemistry of Love, appropriately published on Valentine's Day by Little, Brown ($15.50). A Yale Medical School graduate, Dr. Liebowitz met Sharon, the nurse he later wed, in New York during a community takeover of Harlem Hospital—"a charged setting," he notes, conducive to stimulating attraction. Now 37, he is assistant professor of clinical psychiatry at Columbia University's College of Physicians and Surgeons. In his Manhattan office, he discussed his neurochemical theories of romance with Paula Span for PEOPLE.

Don't you find it distressing to reduce a transcendent emotion like love to a chemical equation?

I'm a big believer in the transcendence of romance. These emotional responses are so powerful that when they're going on, nobody's going to stop to think about the chemicals in his brain. Put it on a more prosaic level: I love French restaurants. I know how digestion works, I know what goes on in my body when I eat something. But that has nothing to do with my enjoyment of a good meal.

How does the brain register emotion?

The brain consists of cells with long tentacles that almost touch the tentacles of the next cell. Chemicals become important in the gaps between the tentacles, called synapses. When a nerve impulse reaches the end of a tentacle, a small packet of chemicals called neurotransmitters is released. Like ferry boats, they float across the gap and hit receptors on the next cell, stimulate it, and the message goes on. There are about 30 known or suspected chemical neurotransmitters. Increases or decreases in their activity level account for changes of mood.

How do chemicals differ in effect?

We think that depression may have to do with not enough activity by a neurotransmitter called norepinephrine; schizophrenia seems to involve too much dopamine. Obsessive compulsions like constant hand-washing may be related to a lack of serotonin. We're at a very primitive stage in our knowledge about this.

And love?

I try to distinguish between romantic attraction and romantic attachment, because I think they're chemically distinct. Attraction has to do with surges of some brain stimulant, perhaps phenylethylamine (PEA). The symptoms of falling in love are very much like what happens when you take amphetamines: Your heart beats faster, your energy goes up, you feel optimistic. There are certain chemicals in the brain, PEA being one, that have amphetaminelike effects. It seems likely that the same neurochemical events that underlie drug states are also involved in feeling attraction.

What, then, is the chemical basis for romantic attachment?

There is an area of the brain stem called the locus ceruleus that seems to trigger feelings of panic and separation anxiety. We know that narcotics like morphine inhibit the locus ceruleus. But there are also naturally occurring brain chemicals, called endorphins, that act like narcotics. I'm hypothesizing that we are genetically programmed to secrete endorphins when we are in close relationships. It's nature's way of keeping us together. Loss of the relationship, or the threat of loss, may shut down endorphin production and throw us into panic.

Why do so many people grow bored with their lovers?

What our brains respond to is chemical change, increase or decrease. Take cocaine, for instance. While the quantity of cocaine in the brain is increasing, the effect is very strong. Once it begins to level off, even though the amount stays high, the effect begins to subside. It's the same thing with a relationship—what's intense is the newness. That used to be the principle behind the honeymoon—a big, sudden dose of intimacy. Kissing and making up after a quarrel also involves a large change in intimacy level. That's why the great romances of literature, if you think about them, are never between people who stay together. Romeo and Juliet, Cathy and Heathcliff—their brains never have a chance to get used to each other, to develop a tolerance for the "high" of love.

Is this an argument for maintaining a mood of insecurity in a relationship? Is that why some people stay attached to partners who treat them badly?

It's an argument for maintaining independence. There's got to be a little bit of uncertainty in a relationship to keep it interesting. People need to be able to hold their own, to leave if things get bad. Staying attached to partners who treat them badly has to do with excessive insecurity. They're too afraid to be on their own.

Where in the brain do pleasurable feelings originate?

The emotional cash register seems to be the limbic system, located just below the two cerebral hemispheres that form the top part of the brain. In humans, the hemispheres are particularly developed, but the limbic system is rather similar in all mammals. Electrodes have been implanted in certain parts of the limbic system of rats, and when allowed to stimulate those parts electrically by pressing a lever, the animals did so over and over. Those areas are called "pleasure centers." There are also thought to be "displeasure centers" in the limbic system. Wired animals will try to avoid anything that stimulates those brain areas.

Why does being in love make everything in life seem delightful?

Roughly speaking, our pleasure centers have a threshold—a minimum level of stimulation needed to make them fire. Thresholds vary. Our mood fluctuations can be linked to changes in those thresholds. Love lowers your threshold, so everything feels possible, everything looks rosy. But that is also the basis of some problems. If your pleasure center threshold is too low, you don't worry enough. For instance, the person you are attracted to is a drinker. So what, you'll reform him. He's been divorced three times? So what, he just hasn't met the right person. You shrug off warning signals.

Do people work better when they're in love, or are they too distracted?

When people's emotional needs are being met, they work better. Love raises your energy, your enthusiasm. You are more likely to be distracted if a relationship is going badly.

What about those roller-coaster lovers who are always falling desperately in and out of love?

The name my colleague Dr. Donald Klein gives this is hysteroid dysphoria. In our anxiety and depression clinics we see people who get very depressed at the end of a romantic relationship. There's nothing abnormal about that, but we see a pattern of romantic breakup and mood crash happening over and over again. It emerges that these people are exquisitely sensitive to rejection and need tremendous attention to feel good. In a relationship, they tend to be very clingy and demanding. If they find suitable partners, frequently they drive them away. When they aren't in a relationship, they feel depressed and immediately have to find another. That drive often leads to a poor choice of partners. Some avoid romance completely after a while.

Is there a chemical solution?

We've been using a special type of antidepressant called MAO inhibitors, which raise the levels of several important neurotransmitters in the brain. In these cases, psychotherapy alone is not particularly useful. But having medication as part of treatment is immensely helpful.

Is there any way we can lower our pleasure thresholds? How do you keep the PEA flowing and ward off tolerance in your own 10½-year marriage?

You need newness, sharing and growth. The brain has to experience a change, or there'll be no excitement. My wife changed careers recently—she's opened a gift shop. We shared that. She had a lot of input into my book; we were able to share that. We're buying a new home, an old farmhouse with a few acres of land. We'll be farmers together in a small way.

So it doesn't have to be candlelit dinners that rekindle romance?

No, that's much too stereotyped. It's anything the two of you find exciting together. But settings are important. They bring back memories, which stimulate the brain chemicals. Put an ex-heroin addict back on the street and he often starts craving again.

If love is chemical, are aphrodisiacs more than myth?

You could take amphetamines and probably fall in love more easily. It's no different from a wartime romance—any time our brains are in an unusual state, it may be easier to fall in love. But unless you stay in that heightened state, it's not going to last.

How about sending Valentine bonbons or roses?

Chocolate does have a lot of PEA in it. But when researchers tried eating chocolate, their PEA didn't go up. PEA in food normally doesn't reach the blood, let alone the brain. Some people say that chocolate is a real up, and we're planning to study it. Is it the sugar? Caffeine? The PEA? Who knows? There's a tremendous PEA factor in roses. But it's in the recipient's brain, which goes bonkers because of what roses mean in our society. My wife's a sucker for roses.

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