The Top Theories To Explain Why We Yawn
If the truth be known we are still not 100% sure why we yawn. Yawning causes are an ongoing subject of scientific study and as time goes by we are getting closer to answering the question. That said there are some very intriguing and robust ideas that go some way to explaining why we yawn and this page outlines the most credible and scientifically backed theories. In fact, it is probably the case that no one independent theory is universally correct, but more likely a combination of all the theories working together. So the hope is that after reading this page you will have a good grasp of the current information available and therefore be able to come to your own informed views and conclusions to the question, Why Do We Yawn.
Yawning Cause 1 - A yawn is the bodies way of controlling brain temperature.
According to a study in America, yawning is directly associated with the regulation of brain temperature. The high complexity of the brain leaves it vulnerable to overheating and the trusty yawn is the remedy. The study was conducted by two chaps called Gallup and Eldakar who tracked the yawning habits of 160 people during the winter and summer months. The study found that people were more likely to yawn during the winter months than the summer months. This is due to the fact that yawning during the summer months has a lesser impact on brain temperature regulation due to the heat of the surrounding air being drawn into the body. When the ambient temperature is lower than the body temperature during the winter months, a yawn helps to draw this cool air into the body and therefore reducing brain temperature. Additionally, blood flow to the brain is increased when the jaw stretches during a yawn, this also thought to increase the cooling effect.
Yawning Cause 2 - A yawn is a physiological consequence directly linked to empathy.
Yawning and empathy seem to go hand in hand. Empathy is defined as "the intellectual identification with or vicarious experiencing of the feelings, thoughts, or attitudes of another", the very fact that yawning is so contagious seems to heavily back-up this theory. Some studies have shown that the more likely you are to catch a yawn from someone the more socially empathetic you are as an individual. And it is a fact that contagious yawning is more common amongst people who are more closely acquainted, for example couples or family members. An experiment carried out in Leeds used neuro-imaging techniques on students to show that the brain area associated with considering others is in fact triggered in the process of yawning. The experiment also observed that the students who scored higher on a robust empathy test showed increased levels of contagious yawning. The reason why yawning is contagious and linked to empathy, like most things, is due to an evolutionary advantage. As we know yawns are commonly experienced before and after sleep and clans of prehistoric man would have benefited from a collective syncing of sleep patterns.
Yawning Cause 3 - Yawns promote alertness and prepare the body for action.
It has been proven that the process of yawning increases blood flow to the brain. One of the brain areas that benefits from this is called the precuneus which is associated with consciousness, memory and coordination. Additionally, yawning is often accompanied by the urge to stretch which could be preparing the bodies muscles and joints for physical action. This seems to suggest that the humble yawn is in fact an evolved survival tool for animals that must snap into action at the first sign of danger. This would explain why people and animals often yawn upon waking. We all know that sleep is an essential part of life but it does leave the body in a vulnerable state. The yawn may have evolved to give the body a boost to counter the suppressed state that we are left in due to sleep. Other studies have backed this theory by showing that people often yawn before a stressful event. For example, yawning has been shown to increase amongst musicians before going on stage to perform, amongst students before sitting an exam, and even amongst nervous people about to take a bungee jump. There is also a link with the alertness theory and the yawn contagion theory. For herd and pack animals it makes sense for yawns to be contagious as it gives everyone the benefit in order to act quick to avoid danger.
Yawning Cause 4 - Yawns are a physical response to brain chemical levels linked to mood and emotions.
We have all heard of the brain chemicals associated with mood such as serotonin, dopamine, glutamine and endorphins, but who would have thought that these natural stimulants would be linked with yawning. Activation of these chemicals in the brain is found to either increase or decrease the frequency of yawns. Increased levels of serotonin and dopamine have been seen to increase yawn activity while chemicals such as endorphins actually reduce yawn frequency. Why these chemicals have this direct link with brain chemicals is still not fully understood, we will be sure to update you on any new breakthroughs.
Check out this cool video about yawning by Vsauce
How many times do we yawn?
The Average person will muster up around 240,000 yawns in their lifetime.How long does a Yawn last?
The Average human yawn lasts for about 6 seconds.When do we start to yawn?
A human foetus begins to yawn from 10 weeks after conception.What muscles are used when yawning?
Yawning involves the use collectively of the thoracic muscles, the larynx, palate and diaphragm.
Which brain area controls yawning?
The lower part of the brain called the brain stem makes us yawn. This area is not consciously controlled. The part coloured black in the image above is the brain stem.How many people search for Why Do We Yawn?
In the UK alone over 20,000 people search for an answer to why do we yawn every month. We aim to answer this question and keep you updated with the current theorems and scientific breakthroughs.How to stop yawning?
We offer some remedies and ideas on how to beat the situations that are most commonly associated with yawning. Check out our ideas to beat sleep deprivation along with our reviews on sleep related gadgets.
Links & Other Cool Sites
- Good old Wikipedia has more info about the humble yawn. Enjoy! Wikipedia
Look at this amazing footage of a fetus yawning in the womb, wow.