This is Scientific American 60 Second Science.

I'm Sophie Bushwick.

Is that person really glad to see me, or are they just being polite?

Some people struggle to distinguish a perfunctory grin from a truly

happy smile, and computers have found this task even more difficult, that is, until researchers trained a program to detect when a smile is genuine.

Visual computing researchers at the University of Bradford in the UK

started with software for analyzing a changing facial expression.

This program can examine a video clip of a human head and identify specific details around

the eyes, cheeks, and mouth. Then the program specific details

then the program tracks the details moving relative to each other as the face smiles.

Next, the scientists had their program evaluate two sets of video clips.

In one, subjects performed posed smiles.

In the other, they watched a film that inspired genuine displays of emotion. The program calculated the differences

among the subject's faces during the two clips, and it turns out that your mouth, cheeks, and

eyes move differently when you're faking that smirk.

In particular, the muscles around the eyes shift 10% more for a real smile

than they do for a fake one. These results are in the journal Advanced

Engineering Informatics. The researchers suggest their work could improve a

computer's ability to analyze facial expressions and thus to interact more smoothly with humans.

But their real accomplishment is improving Tyra Banks right.

You have to smile with your eyes.

Thanks for listening.

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