Everyone wants their partner to be sexy, even if they don't admit it, new research suggests. The need for physical attraction could be why online dating falls flat, since the characteristics in a written profile and image don't line up with how attracted you are to somebody. But a new test can reveal your unconscious desires.

What you say you want in a mate doesn't always match up with what you actually look for, new research suggests, especially when it comes to how sexy your potential partner is.

No matter how much people say they are looking for someone smart, who they can trust and laugh with, they have an unconscious desire to attain a sexually attractive partner — which applies both to men and women, at similar levels — the researchers found.

They even developed a quirky word test to figure out how important physical attraction is to a person, on an unconscious level.

"People will readily tell you what they value in a romantic partner," study researcher Eli Finkel, of Northwestern University, said in a statement. "But study after study shows that those preferences don't predict whom daters are actually attracted to when they meet flesh-and-blood partners. Now we can get under the hood with this quirky methodology to see what people actually prefer in live-interaction settings."

Lab-based dating

In several lab experiments, undergraduate students completed the new computer-based word-association task assessing how much they associate physical attractiveness with an ideal partner. As words flashed on the screen, the participants had to pick those they associated with positive feelings. Depending on how strongly the participant felt about physical attractiveness, words associated with sexiness that popped up during an "I like" trial were selected quicker.

The researchers then compared these results with participants' responses to direct questions about important characteristics in a partner. The two responses differed: No matter if students thought they really needed a hot partner or not, they ended up responding the same to the word test.

The unconscious word test matched with what the students were actually interested in when they met a real-life person in speed-dating scenarios.

"If a person tells me, for example, that she doesn't care about how attractive a guy is, our research suggests that her claim isn't worth all that much," study researcher Paul Eastwick, of Texas A&M University, said in a statement. "Instead, it would actually be more useful to measure her reaction times on this new task," he said, referring to the word-association.

Real-life implications

This mismatch between what a person says they want in a mate and what they're really looking for could be one reason online dating sites sometimes fall flat (even with perfectly matched profiles.

"If you are browsing a bunch of profiles you are assuming you can glean information from those profiles that is actually relevant to how attracted you will be to that person when you meet face to face," Finkel told LiveScience. "People really don't have that level of accurate insight."

It could be possible to use this new tool to test how important physical attraction is to people instead of relying on their questionnaire answers and adjusting their matches accordingly. Or even just providing video-chat capabilities might increase the success rate of first dates.

"We are optimistic that something along those lines would do a better job of approximating face-to-face interaction and would be a more effective means of online dating," Eastwick told LiveScience. "But we haven't done any research on that."

The study was published in the November issue of the Journal of Personality and Social Psychology.

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