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Some researchers hypothesize that contagious yawning is more common in people with greater empathy — the ability to recognize and share other people’s emotions — an idea that has gotten quite a bit of press lately.
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Developmental clues support the empathy theory for contagious yawns. Children younger than about four years old, it seems, yawn spontaneously but don’t catch contagious yawns from adults or from one another. Neither do many older children with autism spectrum disorder, who have an impaired ability to communicate, socialize, and empathize, according to a paper published this summer in Biology Letters.
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The authors found that children with autism yawned spontaneously about as often as children without autism. But when watching videos of yawning adults, children with autism yawned fewer times than other children. They believe this supports the claim that contagious yawning is based on the capacity for empathy.
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Indeed, studies of what’s actually happening in the brain when we see others yawn also seem to support the empathy explanation. For example, in 2005, researchers used an imaging technique called fMRI to see what happens in the brain when people see others yawn. The images showed that in the person seeing the yawn, there was increased activity in the part of the brain involved in self-processing, a region believed to be related to empathy.
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Contagious yawning is not a strictly human habit, though. Research shows that a couple animals related to our species, like chimps, do it too. In one study, British and Japanese researchers showed six female chimps videos of other female chimps that were either yawning or just opening their mouths.
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A third of the chimps yawned significantly more when watching other chimps yawn, while none of them yawned when watching the non-yawns.
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So, yes, it seems that my professor was on to something with his yawning scheme. Not only does research show that yawning is contagious, it suggests yawning weeds out the starers who are a bit less empathetic (too bad the yawning trick won’t weed out the chimps, too).
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