If someone near you yawns, chances are you’re going to yawn too. It’s not just humans, either. Chimpanzees and baboons catch each other’s yawns, and dogs can catch ours. But not everybody finds yawns contagious. Children with autism don’t catch yawns, and researchers think it probably has something to do with their troubles empathizing with others.
But Laura Geggel at the Simons Foundation Autism Research Initiative reports on some new research that suggests it’s not a lack of empathy that causes an autistic child to be immune to social yawns. Instead it’s the fact that autistic children miss the facial cues that trigger our own contagious yawning.
The researchers here tested a handful of children with autism, compared with a handful of controls. The subjects wore eye tracking devices, to show where they were looking, and then watched videos of people yawning or standing still. Some of them were told to watch the eyes of the person in the video, and others were told to count how many people had beards. During these tests, about a third of the kids with autism yawned in response to yawning people—a number in line with the controls. This wasn’t totally what they expected, Geggel writes:
Interestingly, the researchers expected looking at eyes to trigger more yawning than looking at mouths, but both tests provoked equal bouts of social yawns. It’s possible, the researchers say, that children in both groups looked at the yawners’ eyes even during the mouth experiment, which may have triggered their sympathetic yawning. Or, there may be another factor involved in social yawning that the researchers did not measure.
From their work, the researchers now think that simply looking at a persons face is what’s necessary for catching a yawn. Many autistic children avoid eye contact, and in doing so might also be avoiding the contagious yawn. If only that worked for things like the flu.
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