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Which Mitt Romney looks more trustworthy?

The one on the left or the one on the right?

Most people will choose the one on the left, not because he’s showing less teeth and not because of the patriotic background. According to a new study, we judge a person’s trustworthiness by how close up the photo of him (or her) is taken.

The photo on the right is just too close for comfort.

The study, from the California Institute of Technology (Caltech), found that we trust people less, judge them as less competent and find them less attractive when viewing a close-up photo of the person rather than one taken at a distance. It was published in the journal Plos One.

Click here for more on the study.

In four different experiments, testing people in the lab and over the Internet, the Caltech researchers asked participants to rate the trustworthiness of average white male faces.

In all of the experiments, the researchers found that people judged the men as untrustworthy when the photos was taken from a distance of around two feet, compared to photos taken 7-feet away. The researchers chose these two distances because the close up is inside what is considered your personal space (about 3  to 4 feet from the body) and the distance photo was greater than that space.  They conducted four different experiments in order to eliminate confounding factors like expressions, angles, higher resolution and better lighting. They also simply enlarged the distance face and put them next to a close-up face so they were the exact same size, and still the photo taken at a distance garnered more trust.

What accounts for these results?

It’s all about visual distortion.

"It turns out that faces photographed quite close up are geometrically warped, compared to photos taken at a larger distance," explained Caltech’s graduate student and the study’s lead author, Ronnie Bryan. “Features such as the nose and cheekbones that are closer to the camera appear relatively larger compared to features that are farther away from the camera such as the ears and hairline.”

You wouldn’t notice these distortions when you’re far away from someone, but as they get as close as 4 feet, the warping becomes much more pronounced.

“Distance warping alone is enough to make viewers change their opinion about a person-- even when they are entirely unaware that there is any warping (or any change of any kind) in the face,” said Ralph Adolphs, a professor of psychology and neuroscience at Caltech, who co-authored the study.

Previous studies have examined how our social judgments of pictures of people are influenced by factors such as whether the person is smiling or frowning, the width-to-height ratio of a face, the roundness of the cheeks and the large eye size.

“What I find intriguing about our finding is that it shows the extent to which the brain is automatically sensitive to subtle details of facial appearance,” Bryan said.

Since snap judgments based on photographs have been shown to affect voting behavior, it may be helpful to understand what may be influencing you when you go to the polls.