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Just ask Eve. There’s nothing so desirable as the one thing you’re not allowed to have. Which is why a new study suggests that if your partner’s got a wandering eye, you might be better off letting him (or her) enjoy it.

Research on romance has consistently shown that men and women who don’t notice attractive strangers tend to be more satisfied in their own relationships and are more likely to stay with their partners long term. Of course, that blindness has to come naturally. When a person is forced to divert his attention from that cute bartender — by, say, a jealous partner’s opprobrium — it could result in a sort of “backlash” effect, which may end up reducing his level of relationship commitment. (More on Time.com: Does Your Partner Hold Grudges? Blame It on His Mother)

That’s the finding of a new study published in the Journal of Personality and Social Psychology, which tests the “forbidden fruit” hypothesis in a series of experiments on college students who were involved in romantic relationships. Write the researchers:

Just as people want jobs they cannot have, salaries they cannot earn, and cars they cannot afford, people may desire attractive alternatives more and desire their current relationship partner less when they are placed in situations that limit their ability to attend to attractive alternatives.

Certainly, if one partner makes it a habit to drool after attractive strangers while his or her spouse rages with jealousy, there’s probably a larger problem at hand. But the researchers found that the forbidden-fruit effect remained even in cases in which a person’s attention was subtly, unnoticeably restricted. “We proposed that limiting people’s attention to attractive alternatives would undermine positive relationship processes, even when the limitations on attention are posed outside people’s conscious awareness,” the authors write. (More on Time.com: Real-Life Romeos Don’t Compare to Dream Lovers)

The first experiment involved a group of 42 undergraduate students (because, you know, who’s more committed than a 19-year-old college kid?), 25 of whom were women. Three-quarters said they were in committed relationships; the others were mostly casually dating, with a minority of married students. The participants sat before a computer looking at quick-flashing images of face pairs — one attractive, the other average. After the images flashed, one face was replaced with a target letter (E or F), which the participant was instructed to press on the keyboard as accurately and quickly as possible. The program was purposefully rigged to restrict some students’ attention from the more attractive faces, by having the target letter appear in the place of the average-looking face 80% of the time.

Following the computer exercise, all participants filled out questionnaires about their level of relationship commitment and satisfaction (including questions like “How dedicated are you to your relationship?”) and their attitudes toward infidelity (rating statements like “Being faithful to my romantic partner is important to me”). Researchers found that participants who had been unknowingly prevented from looking at attractive faces reported less relationship satisfaction and more positive attitudes toward infidelity than people who were allowed to peep at all faces equally.

A subsequent experiment used the same computer-attention task to show that people who were prevented from gazing at attractive members of the opposite sex were actually more likely to remember them. After having 36 undergrads complete the computer task and then a distraction task, researchers tested the participants’ ability to pick out previously seen attractive faces from a lineup. As the researchers predicted, those whose attention was forcibly diverted — and thus had spent less time looking at attractive faces — were better at recognizing them later on. The effect held for both men and women. (More on Time.com: Texting Leads to Sex Sooner — and Easier Breakups Later)

Having shown that reining in a wandering eye leads people to devalue commitment and remember cute strangers better, in their final experiment the researchers wanted to see if the restriction would also make participants more vulnerable to attractive alternatives later on — at least in terms of attention. Indeed, testing a pool of 158 undergrads, of whom 42% were “dating casually” and 51% were in committed relationships, married or engaged, the researchers found that people whose attention was restricted in the computer task were measurably more engaged by attractive faces in a subsequent task, compared with people in the control group.

The current research has some obvious limitations itself: it involved college students in relatively new relationships; but commitment is known to strengthen over time. It also didn’t follow-up to see whether people’s changes in attitude toward commitment and fidelity led to actual cheating or relationship failure later.

As for the takeaway message here, it’s what you’ve known all along. A partner’s consistently wandering eye probably signals some larger problem that a slap on the wrist isn’t likely to address. The success of your relationship rests on a lot of hard work and constant communication. The authors write:

Being told simply not to look is probably not an effective strategy for boosting satisfaction and commitment or reducing interest in alternatives. To be sure, spending most of one’s time attending to attractive alternatives is not a boon to a good relationship. Probably the most effective solution involves working on enhancing relationship processes that naturally lead to decreased attention, such as focusing on positive aspects of one’s partner.

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