By Tara Parker-Pope
Why do some men and women cheat on their partners while others resist the temptation?
To find the answer, a growing body of research is focusing on the
science of commitment. Scientists are studying everything from the
biological factors that seem to influence marital stability to a
person’s psychological response after flirting with a stranger.
Their findings suggest that while some people may be naturally more
resistant to temptation, men and women can also train themselves to
protect their relationships and raise their feelings of commitment.
Recent studies have raised questions about whether genetic factors
may influence commitment and marital stability. Hasse Walum, a
biologist at the Karolinska Institute in Sweden, studied 552 sets of
twins to learn more about a gene related to the body’s regulation of
the brain chemical vasopressin, a bonding hormone.
Over all, men who carried a variation in the gene were less likely
to be married, and those who had wed were more likely to have had
serious marital problems and unhappy wives. Among men who carried two
copies of the gene variant, about a third had experienced a serious
relationship crisis in the past year, double the number seen in the men
who did not carry the variant.
Although the trait is often called the “fidelity gene,” Mr. Walum
called that a misnomer: his research focused on marital stability, not
faithfulness. “It’s difficult to use this information to predict any
future behavior in men,” he told me. Now he and his colleagues are
working to replicate the findings and conducting similar research in
women.
While there may be genetic differences that influence commitment,
other studies suggest that the brain can be trained to resist
temptation.
A series of unusual studies led by John Lydon, a psychologist at
McGill University in Montreal, have looked at how people in a committed
relationship react in the face of temptation. In one study, highly
committed married men and women were asked to rate the attractiveness
of people of the opposite sex in a series of photos. Not surprisingly,
they gave the highest ratings to people who would typically be viewed
as attractive.
Later, they were shown similar pictures and told that the person was
interested in meeting them. In that situation, participants
consistently gave those pictures lower scores than they had the first
time around.
When they were attracted to someone who might threaten the
relationship, they seemed to instinctively tell themselves, “He’s not
so great.” “The more committed you are,” Dr. Lydon said, “the less
attractive you find other people who threaten your relationship.”
But some of the McGill research has shown gender differences in how
we respond to a cheating threat. In a study of 300 heterosexual men and
women, half the participants were primed for cheating by imagining a
flirtatious conversation with someone they found attractive. The other
half just imagined a routine encounter.
Afterward, the study subjects were asked to complete fill-in-the-blank puzzles like LO_AL and THR__T.
Unbeknownst to the participants, the word fragments were a
psychological test to reveal subconscious feelings about commitment.
(Similar word puzzles are used to study subconscious feelings about
prejudice and stereotyping.)
No pattern emerged among the study participants who imagined a
routine encounter. But there were differences among men and women who
had entertained the flirtatious fantasy. In that group, the men were
more likely to complete the puzzles with the neutral words LOCAL and
THROAT. But the women who had imagined flirting were far more likely to
choose LOYAL and THREAT, suggesting that the exercise had touched off
subconscious concerns about commitment.
Of course, this does not necessarily predict behavior in the real
world. But the pronounced difference in responses led the researchers
to think women might have developed a kind of early warning system to
alert them to relationship threats.
Other McGill studies confirmed differences in how men and women
react to such threats. In one, attractive actors or actresses were
brought in to flirt with study participants in a waiting room. Later,
the participants were asked questions about their relationships,
particularly how they would respond to a partner’s bad behavior, like
being late and forgetting to call.
Men who had just been flirting were less forgiving of the
hypothetical bad behavior, suggesting that the attractive actress had
momentarily chipped away at their commitment. But women who had been
flirting were more likely to be forgiving and to make excuses for the
man, suggesting that their earlier flirting had triggered a protective
response when discussing their relationship.
“We think the men in these studies may have had commitment, but the
women had the contingency plan — the attractive alternative sets off
the alarm bell,” Dr. Lydon said. “Women implicitly code that as a
threat. Men don’t.” Continue Reading at NyTimes.com
Tara Parker-Pope’s new book is “For Better: The Science of a Good Marriage.”