Have you been beside someone who’s yawning, only to find yourself uncontrollably, subconsciously yawning seconds afterwards?

Well, there’s a scientific reason for that.

We reciprocate yawns because it’s hard-wired into our brains – a primitive reflex that’s not completely understood.

Researchers from the University of Nottingham in England point to a human trait called echophenomena as the culprit of triggering involuntary yawns.

Echophenomena encourages us to imitate people’s actions and words, the researchers report in their study, published in Current Biology. The trait is also present in neurodevelopment conditions such as Tourettes, autism and epilepsy, where researchers are still seeking alternative treatments.

In the study, the researchers took 36 participants, and had them watch videos of people yawning. The team tallied each reciprocated yawn, and yawns that the participants tried to hold back.

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The team discovered that suppressing a yawn after someone else does it is ‘restricted’, and is more difficult when someone points out not to do it. An interesting note the researchers documented is the addition of electrical stimulation, which drove a necessity to yawn; this newfound tidbit may lead to medical advances for neurodevelopment conditions in the future.

“Using electrical stimulation, we were able to increase excitability and in doing so increase the propensity for contagious yawning,” said Georgina Jackson, a professor in cognitive psychotherapy at Nottingham.

“In Tourettes, if we could reduce the excitability, we might reduce the ticks.”

The researchers noted this phenomenon is not exclusive to humans, but is a trait shared by chimpanzees and dogs.

The jury is still out as to why we yawn, which continues to vex researchers – there’s simply not enough evidence to prove or disprove anything.

For example, there are theories that point to why we yawn, from a lack oxygen to a need to ‘cool the brain’, but the evidence is thin.

Contagious yawns have their own separate set of theories, too.

“The popular theory for contagious yawning is that it is linked with empathy for others, mimicry and social bonding,” said Stephen Jackson, a professor of cognitive neuroscience at Nottingham, who led the study.

“But again, the evidence for this is weak. I still think that much more research is required to understand the function and biology of yawning.”

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