They say you go a little crazy when you fall in love,but do they really
mean clinically mad?
Kathryn S Brown
AS summer days heat up, so do summer lovers. There they are,
at the beach, in the store, on the corner-couples who stand so close and
stare so longingly that you blush just watching them. It's love. It's perfect,
sweet-and so definitely sick.
Songwriters have long crooned that love is insane. But scientists now have
a more precise term for it: obsessive compulsive disorder (OCD). Made
famous by checkers and washers-people who check and recheck the door to be
sure it's locked, or repeatedly try to wash away germs-OCD endlessly nags
sufferers with intrusive, anxious thoughts. Heeding these voices, people
with OCD feel compelled to repeat mundane activities or chase risky thrills,
That may not sound like blissful love, but some psychiatrists now say that
passion's thrills do indeed resemble OCD's angst, both in outward habits
and the brain's inner chemistry. Love is just a lot more fun. What's more,
these researchers say, the pathology of romance may play a pivotal role in
our evolution. Their ideas are
raising eyebrows-and causing a few giggles-among scientists. And their
conclusions might just explain why love makes you do such utterly foolish
It all started in 1990, when Donatella Marazziti a psychiatrist at the University
of Pisa in Italy, began looking for biochemical explanations for OCD. One
chief suspect was the neurotransmitter serotonin-a chemical that has a soothing
effect on the brain. Too little serotonin has been linked to aggression,
depression and anxiety; drugs in the Prozac family fight these conditions
by boosting the chemical's presence in the brain. So Marazziti set out to
measure serotonin in people with OCD.
Tracking chemicals inside the brain is tricky, so she settled
on a simpler technique: calculating the amount of serotonin in platelets,
tiny cells that are easily retrieved from an ordinary blood sample. In blood
platelets, serotonin plays a totally different role-aiding clotting-but moves
about in much the same way as it does in the brain. Which means that scientists
can gauge roughly how much serotonin is skipping about your head from the
levels of related proteins in platelets. It may be an indirect measure, explains
molecular biologist Dean Hamer of the National Cancer Institute (NCI) near
Washington DC-but it can hint at how relevant the chemical is to different
forms of behaviour.
And, as Marazziti predicted, she found evidence that serotonin levels were
unusually low in people with OCD. But she also discovered something surprising.
Interviewing these patients, Marazziti was struck by the way their persistent
one-track thoughts mirrored the musings of people in love. Throughout the
day, both the people with OCD and the lovestruck can spend hours fixating
on a certain object or that certain someone. What's more, both groups often
know their obsessions are somehow irrational, yet they can't snap out of
them. Marazziti had to wonder, if serotonin dips dangerously low in OCD,
could it be doing the same when people fall in love?
To find out, Marazziti's team went looking for love. They pinned
advertisements around the University of Pisa medical school asking for students
who had fallen in love within the past six months and who had obsessed about
their new love for at least four hours every day but who had not yet celebrated
the relationship with sex. They wanted to find Romeos and Juliets whose fresh
passion had neither been hormonally jumbled by sex nor dulled by time. Seventeen
women and three men with an average age of 24, signed up. Separately, the
scientists recruited 20 people who met the basic criteria for OCD and another
20 free from the grip of either love or psychiatric disorder.
Blood samples were taken from each member of each group, and then spun in
a centrifuge to separate out first the plasma and next the tiny platelets.
While the "normal" students had the usual level of serotonin, both the OCD
and in-love participants had about 40 per cent less of the chemical as estimated
by the amount of activity of a serotonin transporter protein in their blood
platelets. "It's often said that when you're in love, you're a little bit
crazy," Marazziti says. "That may be true."
To confirm their hunch that serotonin plummets solely during love's first
flush-and not later on-the researchers retested six of the original 20 in-love
students a year hence. Sure enough, the students' serotonin levels had bounced
back to normal while a more subtle affection for their partner had replaced
their original giddiness. According to previous studies, the same "evening
out" of emotion happens to OCD patients who take drugs that boost serotonin
levels to normal.
The offbeat study, just published in the journal Psychological
Medicine (vol 29, p 741, 1999), has researchers applauding, chuckling-and
wondering whether this is a tentative first step towards some interesting
conclusions about life and love. "Bravo!" says Thomas Insel director of Emory
University's Yerkes Regional Primate Research Center in Atlanta. "As scientists,
we're very quick to study stress, aggression, or grief, but what of love?
Why shouldn't we know about this emotion, too? Any of us who have fallen
in love know that this is a profoundly biological process. Now somebody's
actually trying to understand how."
Some scientists wonder what they've been missing all these years. "Four hours
a day!" marvels Yvette Sheline, a psychiatrist at Washington University in
St Louis. "Who spends four hours a day thinking about someone?" The new findings
may explain some quirks of human behaviour, too-such as why we feel unusually
passionate after downing a few pints. Abdulla Badawy; a biochemist at Whitchurch
Hospital in Cardiff, Wales, has shown that alcohol seems to deplete serotonin
in the brain, and that this chemical imbalance makes some people quick to
fight. Given the new study, Badawy speculates that plummeting serotonin might
also dissolve inhibitions-creating a passionate haze that lures you into
thinking that the person at the other end of the bar is unbelievably attractive.
So choose your bars carefully.
'As scientists, we're very quick to study stress, aggression, or grief, but
what of love? Why shouldn't we know about this emotion, too?'
On a more serious note, scientists who study OCD say the comparison
with new love may be quite fitting. Eric Hollander, director of the Compulsive,
Impulsive, and Anxiety Disorders Program at Mount Sinai School of Medicine
in New York, says that while most people associate OCD with anxiety, it actually
represents a broad spectrum of conditions, some of which-impulse stealing,
shopping and gambling-bring a jolt of pleasure. Romantic love might fit in
here, he says.
Hollander has studied another heart-wrenching emotion affiliated with OCD:
obsessive jealousy. One of his patients was convinced that his wife
was having an affair. Every day, he quizzed his wife about where she'd been
and who she'd seen. He also insisted that she keep all windows in the house
covered and go to the beach fully dressed, so that strangers couldn't sneak
a peek. Hollander gave this patient and five others Prozac-like drugs to
enhance serotonin levels. After treatment, the man-who also had classic OCD
checking compulsions-relaxed quite a bit. The lesson, Hollander says, is
that persistent, intrusive emotion-whether it is breathless love or nervous
jealousy-can arrive with OCD-like intensity.
To be sure, Marazziti's new study is preliminary. Because platelet measures
simply estimate overall serotonin, they can't pinpoint specific changes in
the brain. Moreover, the study is small, and the in-love participants are
mostly women-though men and women may process serotonin differently. Marazziti
is quick to call the research just a first step to understanding the biochemical
markers of love.
Image of perfection
Cupid's chemicals certainly merit a closer look. Our fate -not to mention
that of our genes-rests, in part, on the firings of neurotransmitters like
serotonin, suggests Hagop Akiskal, a psychiatrist at the University of California
in San Diego and one of Marazziti's co-authors on the new study. Without
intense emotion, which typically creates an unrealistic image of the love
object, rather like a photo that's perfectly airbrushed, nobody in their
"right" mind would fall in love, Akiskal says. By reeling you in and stringing
you along, making you believe that you've caught the one heart-stopping fish
in the sea, the argument goes, serotonin keeps love's fires burning long
enough for romance to yield an evolutionarily satisfactory end: offspring.
For people with chronically low serotonin, in fact, life tends to be unusually
sexy. According to studies by Hamer at NCI and his colleagues, men with a
"short" version of the serotonin transporter gene, which results in reduced
serotonin, tend to be both more anxious and more sexually active than those
with a longer version of the gene. While these easy lovers keep the gene
pool going, they also litter it with neuroses, Hamer notes. "Genes don't
care how crazy you are. They get passed on." Pausing a moment, Hamer adds:
"Well, if you're utterly crazy, it's harder to find a mate-at least if
you're a male."
Love's chemistry can create other types of wildly passionate
temperament, too. In 1996, two teams of researchers traced
novelty-seeking to a particular polymorphism in the gene that encodes
the D4 dopamine receptor. Some of the gene's inheritors may
seek thrills in love, Akiskal says. But he thinks
the "great romantics" are people suffering from cyclothymia, a bipolar disorder
somewhat like manic-depression, that brings alternating periods of intense
excitement and gloom.
According to Akiskal's research, people with cyclothymia fall in love during
happy times, often indiscriminately. This undiscerning pursuit of love creates
much mixing of genes in the sex that follows. However, Akiskal says, the
inevitably fades, as severe melancholy sets in, sometimes leading to suicidal
depression for the person with cyclothymia and potential danger for his
or her love interest. It is passion's dark side-and researchers would
dearly love to understand the chemistry behind it.
When possible, scientists like to unravel biological mysteries
with animal models. But how do you make a rat fall in love? Geoffrey Miller,
an evolutionary psychologist at University College London, notes that while
many species mate, scientists have no clue how many actually feel romantic
yearnings. After all, once a baby is born, it's not romance-but a deeper
attachment-that convinces parents to jointly care for their cute bundle of
Ah, but then love comes full circle, at least in the animal kingdom. Scientists
regard prairie voles -fat little rodents rather like squirrels-as nature's
ultimate significant other Amid surging dopamine, voles pledge lifelong monogamy
to a partner. Perhaps, researchers reason, we lovestruck humans can learn
from these simple creatures. On the other hand, ever when a female vole is
deprived of sex, yet given just a dose of dopamine she chooses any nearby
male as her mate for life. Now, how sick is that?
Kathryn S. Brown is a science writer based in Columbia