Yawning is mysterious: no-one really knows why we do it, but we do know it’s reliably ‘contagious’.
Seeing someone yawn, or indeed, just thinking about someone else yawning, makes us more likely to do the same. For example, this article may well be enough to trigger a yawn in some people.
One of the three key aspects of autism is a difficulty with social interaction (the other two being difficulties with certain types of abstract thinking and a restricted or repetitive range of interests or behaviours).
So a group of researchers, led by psychologist Dr. Atsushi Senju, wondered whether children with autism might be less susceptible to yawn contagion.
They came up with the ‘I wish I’d thought of that’ idea of showing videos of people yawning to groups of typically developing children, and children with a diagnosis of autism.
The study [pdf] showed that children with autism were far less likely to yawn in response to watching others do the same.
Often, autistic social difficulties are put down to a problem with ‘theory of mind‘ the ability to understand other people’s beliefs, intentions and desires, but it’s not clear that contagious yawning relies on this.
The researchers don’t have any easy answers for why yawn contagion is reduced in autism, but suggest, without committing, that known differences in viewing faces, possible differences in mirror neurons or problems with imitating others might be linked.
The BPSRD has a talent for picking up on previously obscure but striking studies, and this is another great example.