Ever noticed that you find it hard not to yawn when you see someone else doing it? It could say a lot about your brain.
New research by the University of Nottingham has found that we automatically want to yawn when we see someone else doing it, although how strong our urge to do so ranges from person to person.
It is also even more difficult to stop yourself yawning when you are trying to not do it.
These findings have implications not just for tired workers but also for the study of conditions such as epilepsy, dementia and Tourettes, which could be caused by difficult to suppress brain signals.
Stephen Jackson, professor of cognitive neuroscience, in the School of Psychology, led the multidisciplinary study. He said: “Most of our work is aimed at understanding those disorders.
"We use yawning as a way of studying the human brain, as the difference between how likely you are to yawn when you see others doing it is based on the balance between excited neurons and inhibited neurons in each individual’s brain.
“This process may also cause ticks and helps us to understand how they come about, putting us in the right direction for finding new types of treatment.”
Their study — ‘A neural basis for contagious yawning’ — has been published in the academic journal Current Biology.
They recruited 36 adults to help with their research. These volunteers viewed video clips showing someone else yawning and were instructed to either resist yawning or to allow themselves to do it.
The participants were videoed throughout, and their yawns and stifled yawns were counted. In addition, the intensity of their urge to yawn was continuously recorded.
This urge to copy someone else is called econophenomena, the automatic imitation of words and actions, and it has been observed in dogs and chimpanzees as well as people.
The research seems to show that this comes from primitive reflexes in the part of our brain which is responsible for movement, and by stimulating this with electricity it is possible to increase the desire to yawn.
Individuals who have more excitable brain signals might find it more difficult to suppress urges such as yawning.
This means that controlling how excited this part of the brain is becoming could help manage conditions that are caused by too much or too little physiological inhibition.
For example, ticks in Tourette patients could be caused by too many excited signals in the brain and not enough inhibitors, leading to an irrepressible urge to do something.
Georgina Jackson, professor of cognitive neuropsychology in the Institute of Mental Health, said: “This research has shown that the ‘urge’ is increased by trying to stop yourself.
“Using electrical stimulation we were able to increase excitability and in doing so increase the propensity for contagious yawning.
“In Tourettes if we could reduce the excitability we might reduce the ticks and that’s what we are working on.”