If you don’t yawn when someone else does, you might be a psychopath

When one person yawns in a room, does that make you yawn, too? If so, you should feel good about yourself. It’s a sign of empathy. If not, you might want to seek help.

As it turns out, those who yawn when others yawn — the “contagious yawn,” if you will — are not just also tired. They are showing empathy for the other person. And now a new study from Texas Baylor University. shows that psychopaths are almost never affected by contagious yawning. If you want to know if someone is cray-cray, just yawn.

Crazy, right? But maybe not. It really is kind of a part of being in a community and caring about others. Oh you are tired? Me too! Me too!

So why is this?

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The researchers found that students who showed high cold-heartedness were less likely to yawn.

“One of the biggest lines of evidence is that contagious yawning is very much related to empathy,” said Brian Rundle, a PhD scholar who worked on the study. “While this is a really interesting finding, it doesn’t mean that if you’re not affected by a contagious yawn there’s something wrong with you.”

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OK, big relief. But even so. This would be a useful little trick on a date. Give a little yawn and see what he or she does in response. If they yawn, too, well they pass the test. If not? Yikes. Obviously it’s not fool proof, but it’s something.