We’ve all done it, and in fact, it’s pretty hard to restrain from it! That’s right it’s the contagious yawn.
You may not even feel particularly tired, but as soon as you see someone else yawn, you suddenly feel the need to want to yawn yourself, and in fact, roughly half adults yawn after seeing someone else yawning!
Even the thought of yawning can trigger it off so don’t be surprised if you end up yawning whilst reading this blog!
How is it triggered?
You might have wondered what the cause behind this contagious phenomenon is.
Neuroscientist and yawn expert Robert Provine claims that yawning is “ancient and automatic”. Originating from early evolution, yawning is common to a number of creatures, even fish! Common causes of yawning tend to relate to boredom, sleepiness and temperature.
‘Copycat yawning’ according to an article published on mental_floss discussing why yawning is so contagious says that scientists have found that other animals, as well as humans, are subject to contagious yawning too, including chimpanzees, baboons, bonobos, wolves and sometimes even dogs.
Whilst yawning usually involves a wide open mouth, research has also shown that ‘yawning eyes’ can be enough to make someone yawn!
An article published on BBC News online magazine claimed that ‘the brain cooling theory’ says that contagious yawns are the result of an ancient ritual hardwired within us in order to help keep us awake, alert and react to danger and isn’t the result of copying sleepiness.
Gordon Gallup, a leading researcher from the University of Albany in New York says in response to this theory that: “We think contagious yawning is triggered by empathic mechanisms which function to maintain group vigilance,”.
An exploration into yawning has also revealed that people with autism or schizophrenia aren’t affected by contagious yawning, as well as children under four years.
This observation led to theories about empathy and the brains mirror-neuron system (MNS) in which a deficit of MNS could result in a lack of empathic signals which causes yawning.
However, further research and MRI scans have also highlighted that other parts of the brain appear reactive when individuals were shown pictures of yawning.
Unconscious ‘herding behaviour’
The same BBC News article also suggested another interesting theory why contagious yawning occurs which is to do with an unconscious herding behaviour as we try to communicate to those around us.
Furthermore, other beliefs think that the early human species used yawning to help in communicating alertness levels and sleeping times. An individual would yawn to show that they were ready to go to sleep and the rest of the group would yawn back to show that they agreed.
Despite a popular belief being that yawning results from factors such as empathy, energy levels and tiredness, a study conducted by Duke University says that there could be more to it than this.
The research carried out by the Duke Center for Human Genome Variation published back in 2014 was said to be one of the most detailed studies investigating the causes of contagious yawning.
The study’s author, Elizabeth Cirulli, Ph.D., assistant professor of medicine at the centre said that: “The lack of association in our study between contagious yawning and empathy suggests that contagious yawning is not simply a product of one’s capacity for empathy.”
The study’s results did not find a strong association between yawning and empathy, intelligence or time of day.
However, the independent factor which seemed to influence yawning was age. As the participants of the study’s age increased, the rate of yawning decreased. On the other hand, this finding could only explain 8% of the responses to contagious yawning meaning that the majority of yawning variation between participants were unexplained.
Further details surrounding the Duke University’s research can be found by heading to Psychology Today.
As you’ll have seen, a number of theories exist which try to explain the origins of the contagious yawn meaning the causes of why we can’t help but yawn when we see someone else do it are not set in stone, however, it appears that empathy and our need to communicate may well be factors influencing contagious yawning in past times.