Did you yawn looking at this photo? Don’t worry, we do too.
Yawning is an involuntary reflex of having less oxygen in our body than we need.
But oddly enough, we tend to yawn when we’ve seen someone else yawn, or think too much about yawning.
So why exactly do we yawn, what does it do to our bodies – and why is it so contagious?
Let’s find out.
Why do we yawn?
If you’re bored or tired, your breathing will slow, causing you to take in less oxygen. So your body will trigger a yawn to help you breathe more.
It has also been suggested that yawning is a way to cool your brain, to prevent brain overheating.
In short, more people yawn in summer than in winter.
It’s a way to increase your heart rate blood flow and use of facial muscles which all help cool the brain.
Your brain is more likely to overheat when you’re exhausted or sleep deprived, which is why you yawn at these times.
But if that is the cause of yawning, why do you yawn in response when you see someone yawn?
Why is yawning contagious?
Contagious yawning isn’t as scary as it sounds, and we’ve all experienced it.
When someone else yawns, we yawn. When someone talks about yawning, we yawn. The sound of a yawn makes us yawn.
Yawn contagion is a cross-species phenomenon. It has been tested on chimpanzees, to see if they yawn while watching other primates yawn (answer: they do).
More recently, it has been revealed that domestic dogs have the contagion from their owners’ yawns.
There are many theories as to why this happens.
Some say it’s related to empathy, while others suggest that it’s us who imitate others because of neurological stimulation.
Contagious yawning begins when a child is around four or five years old. It is at this age that the child begins to develop empathetic behavior and begins to recognize emotions in others.
You are more likely to yawn in response to someone socially or genetically close to you, and dogs are more likely to yawn in response to their owner’s yawn.
The other theory is that contagious yawning is caused by mirror neurons.
These neurons fire both when an animal acts and when an animal sees another animal act.
So when we see someone yawn, the mirror neurons stimulate that familiar action in our mind, the neurons then cause us to yawn, mimicking the action we see.
If you use mental imagery of a yawn and really focus on it, you can probably make yourself yawn through mirror neurons.
Mirror neurons help you feel what other people are feeling, and that’s why you’re more likely to yawn if you see someone you’re in a relationship with yawning.
People with empathy disorders such as autism yawn less when they see others yawn, and it seems that psychopaths are immune to contagious yawns.
Since another trait of psychopathy is fearlessness, it was found in a contagious yawn experiment that people who were less likely to startle were less likely to catch a yawn.
All animals with a spine are thought to yawn, penguins do it as a mating ritual, snakes do it to realign their jaws after eating, and guinea pigs do it to display their anger.
Babies can yawn in the womb, and it starts in the second trimester.
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