Beware the bedroom eyes, guys -- new research suggests that a heavy-lidded, seductive gaze makes you seem less trustworthy to both men and women.
The study finds that guys with an open, normal gaze are preferred for a long-term relationship by women and as a business partner or neighbor by men. Women and men alike perceived the eyes-half-closed look as an attempt to secure a fling rather than a long-term relationship.
"A lot is conveyed in a glance," study researcher Daniel Kruger, a psychology professor at the University of Michigan, told LiveScience.
It's all in the eyes
Large eyes convey childlike qualities such as naivety, sincerity and vulnerability. Gaze and pupil size also convey personality traits and mood, including extroversion and sexual arousal. With eyes conveying so much, Kruger and his colleagues wondered: What about eyelids?
Kruger and his co-author Jory Piglowski, also of the University of Michigan, took photographs of two men, both white and in their early 20s, with eyes open and half-open. They used computer-editing software to overlay the photographs so that they were identical in all aspects except for eye openness.
In two studies, the first with 239 undergraduate men and women and the second with 161 undergraduate participants, the researchers showed volunteers the photographs and asked the female participants to rate them on attractiveness for a short-term relationship, long-term relationship and brief affair (or fling). Women were also asked whether they'd like each man to be the father of her child or whether they'd trust him to accompany her sister on a long trip. Men were asked if they'd like the man as a son-in-law or whether they'd be okay with him traveling with their girlfriend on a long trip. They were also asked if they'd like the man as a business partner or neighbor.
The results showed that the squinty-eyed guy was less appealing as a long-term relationship prospect than the guy with the open gaze. The heavy-lidded man was seen as pursuing a short-term mating strategy -- in other words, a fling rather than a relationship, the participants indicated. Unfortunately, the look didn't give him much of an edge: Men with a wider-eyed look were ranked as more attractive even for a brief affair. [The Sex Quiz: Myths, Taboos & Bizarre Facts]
Men were less likely to want the seductive gazer as a neighbor or business partner, and women were less likely to say they'd want to marry him, with 71 percent picking the open-eyed guy instead. Open-eyed guys were also seen as more trustworthy when accompanying a woman on a trip.
The researchers also picked two literary descriptions from British Romantic literature, one of a cad or dark hero (George Staunton from Walter Scott's 1818 book "The Heart of Midlothian) and one of an upstanding hero (Waverley, from the book "Waverley" by the same author). When they asked the participants to match the man to the description, they matched the squinter to the cad and the open-eyed guy to the knight-in-shining-armor type.
Gaze with caution
The seductive gaze may well convey a sense of maturity and sexual readiness, given that larger eyes are associated with youth, Kruger said. But the study, published in the April issue of the journal Personality and Individual Differences, suggests that an all-around seductive look "can come back to bite you," Kruger said. He and his colleagues have since conducted a similar study using female faces and shown the same results.
"You don't gain so much of an advantage by doing this [expression] unless you're already engaged with someone who is interested in you, or who you have a chancewith," Kruger said. "So don't overuse it."
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