You’ve probably experienced the phenomenon yourself — you see someone yawn, and all of a sudden you’re yawning too. Echophenomena is the term for contagious movements such as yawns, more commonly its known as contagious yawning, and it happens for around for 60% to 70% of people. You may get an urge to yawn even while reading this article, a new study suggests.
Experts at the UK’s University of Nottingham have published research that suggests the human propensity for contagious yawning is triggered automatically by primitive reflexes in the primary motor cortex – an area of the brain responsible for motor function.
The study examined the brain activity of a person when someone “catches” a yawn from another person, or a photo or video. The researchers observed 36 adults, who were made to watch videos of another person yawning. They measured the participants’ brain activities during the experiment through transcranial magnetic stimulation (TMS).
A participant’s risk of “catching” a yawn correlated with the excitability of his or her primary motor cortex, a part of the brain that controls your movement. The more excitable the cortex seemed to be, the more easily the participant caught a yawn.
The new study takes the yawn research one step further, suggesting that trying to stifle those involuntary stretches only makes the urge to yawn even stronger.
The scientists found that those who were instructed not to yawn did end up committing fewer full-out, wide-open-mouth yawns. But the scientists counted more stifled (yet still noticeable) yawns in this group, and the participants reported stronger urges to yawn than the group that was allowed to do so.
In other words, “the ‘urge’ to yawn is increased by trying to stop yourself from doing so,” senior study author Georgina Jackson, a professor of cognitive neuropsychology at the University of Nottingham, said in a press statement published by the varsity.
Understanding what makes us yawn, and what triggers the urge to do so, may also help doctors better understand these types of neurological and psychiatric conditions. If they could reduce excitability in patients with Tourette’s syndrome, for example, they may be able to reduce the frequency of involuntary movements or outbursts, known as tics.
“We suggest that these findings may be particularly important in understanding further the association between motor excitability and the occurrence of echophenomena in a wide range of clinical conditions… such as epilepsy, dementia, autism and Tourette syndrome,” said study leader Stephen Jackson. He’s a professor of cognitive neuroscience at Nottingham.
And interestingly enough, it’s not just humans who have a propensity for contagious yawning – chimpanzees and dogs do it too.