Our brains may have developed a way to help keep us from cheating — or, at least, to make cheating less appealing.
People in relationships find "threatening" (i.e. available) attractive individuals less attractive than single people do, according to a study published on May 20 in Personality and Social Psychology Bulletin.
And if they're in happy relationships, people are even more likely to think other potential mates are unattractive.
To test this phenomenon, researchers first confirmed that a method to alter facial attractiveness (based on previous research) did in fact change people's perception of how good looking someone was without alerting them to the fact that that's what was being changed. (For this, they relied on Amazon Mechanical Turk users: anonymous people who respond to researchers' questions — and complete other tasks — in exchange for very small sums of cash.)
This is what the faces looked like, with the actual photo of a man in the middle, his altered less attractive versions on the left, and the more attractive ones on the right:
Next, the researchers told 131 straight college students that they'd be working closely with someone of the opposite sex (who actually didn't exist), then shared their hobbies, relationship status, and a photo.
The participants then had to match the person's photo to the altered images of their face in what they thought was a memory test. Remarkably, people in relationships consistently chose the fake person's less attractive photos if he/she was single, which the researchers called a "high threat."
In a second test, 114 different straight college students filled out questionnaires about how happy their relationships were if they were in one, then repeated the first test. Again, people in relationships thought the fake person was less attractive if he/she was a high threat, and this effect increased if they said they were in happy relationships.
While college students are not a representative sample, and face-matching in a lab is not akin to meeting people out in the world (the participants in this study were not drinking at a dimly-lit bar, for example), previousresearch has found similar results — though the researchers here note that theirs is the first study to use faces that differed in attractiveness. Others have relied on questionnaires asking people directly whether they found someone attractive, which can alert participants that that's what the researchers are studying, potentially yielding less reliable (and honest) results.
This finding is rather comforting for couples and suggests that "I only have eyes for you" is more than just a suave line. If your partner meets someone who's attractive and available, they probably won't think that person is as good looking as they really are.
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