Don’t yawn, whatever you do!

Did you yawn just looking at this picture? Why are such common everyday actions so misunderstood and mysterious to us?

Let’s start with this very common action of yawning. The original hypothesis of yawning was when the body had a build up of carbon dioxide and lack of oxygen, the brain stem would activate the yawn reflex to help normalize CO2 and O2 within the blood. This hypothesis is now deemed incorrect after a study was done by Robert R. Provine. Every explanation as to not only why we yawn, but why it seems so irresistibly contagious has been inaccurate or debunked. In lieu of these old inaccurate explanations, the scientific community has been a twitter with the latest discovery of very special cells called mirror neurons within the last decade. These have been more or less known in primates, but not quite enough research has been done with humans to determine whether it is fact whether we carry the same extraordinary nerve cells.

What was found was that yawning, at least the contagious part, is more about social behavior and non-verbal unconscious communication. Nearly all vertebrates yawn, but the contagious yawning only exists in a very small portion of highly socialized animals. It seems that a certain part of the brain “sees” the action then suggests that we, the observer, need to repeat the action. With the discovery of mirror neurons, this may be the answer that we have been looking for. So what exactly are mirror neurons? Here is a basic example of what they are:

A mirror neuron is a neuron which fires both when an animal performs an action and when the animal observes the same action performed by another (especially conspecific) animal. Thus, the neuron “mirrors” the behavior of another animal, as though the observer were itself performing the action. These neurons have been directly observed in primates, and are believed to exist in humans. In humans, brain activity consistent with mirror neurons has been found in the premotor cortex and the inferior parietal cortex.

The suggestion is that these mirror neurons are responsible for how we learn to become social beings. According to Scientific American, these neurons are the rationale behind why children seem obsessed with watching us perform daily actions and seem to mimic everything that we do. This may also explain how we can read people or observe people’s intentions, say when people lie, even though they don’t verbally say what they are truly thinking. Since we have spent our entire lives from birth observing others and learning how to do the same, we may perceive behaviors that we do when we lie and unconsciously notice those same behaviors in others. Have you ever had the feeling that someone was not being honest? Or, you just can’t trust him? Your mirror neurons may be whispering suggestions into your consciousness.

Artist’s rendering of neuron cluster.

Scientific American also goes on to say that autism may be explained through the lack of or damage to these mirror neurons. This may be a great explanation of why they seem to suffer in the realm of socialization. Any experience with a child that has autism will immediately open your eyes to the apparent social inabilities that plague the condition. Often they can’t look you in the eye, have an inability to focus their attention or engage, or they may fidget, rock back and forth. The whole interaction may seem very little like an interaction at all. Interestingly enough, these children have ability to experience their own fear, pain, loneliness, but often lack all abilities to understand and read the same feelings in another. A deficiency in mirror neuronal activity may result in a sense of blindness to other people’s feelings or emotion during interaction, unlike healthy, “normal” children where these subtle clues of emotions are obvious.

If we go back to yawning, we will see that yawning may have several different definitions often being incomplete in explanation or theoretical at best. Here is what Wikipedia says about yawning:

Definition – A yawn is a reflex of deep inhalation and exhalation associated with being tired, with a need to sleep, or from lack of stimulation. Pandiculation is the term for the act of stretching and yawning. Yawning is a powerful non-verbal message with several possible meanings, depending on the circumstances. It is also claimed to help increase the state of alertness of a person… The exact causes of yawning are still unascertained.

Rationale — 1. An indication of tiredness, stress, over-work, lack of directed attention or boredom.
2. An action indicating psychological decompression after a state of high alert.
3. A means of expressing powerful emotions like anger, apathy, apprehension, remorse or tedium.

Contagiousness — At a distal level (in terms of evolutionary advantage), yawning might be a herd instinct. Other theories suggest that the yawn serves to synchronize mood behavior among gregarious animals, similar to the howling of the wolf pack. It signals tiredness to other members of the group in order to synchronize sleeping patterns and periods of activity… Oddly, sometimes sympathetic yawning may be caused by simply looking at a picture of a person or animal yawning, or even seeing the word yawn. A specific study was conducted on chimpanzees. A group of chimpanzees was shown a video of other chimpanzees yawning, and the study chimpanzees yawned also.

As far as the contagiousness, it very well may be a primitive form of communication. This kind of non-verbal, physical conveyance of tiredness, boredom or lack of interaction may have been the first form of communications to the group that may predate the creation of language. Yawning may be associated with the contagiousness of laughing, crying, rage; it seems that all the most primitive forms of emotional expression is either slightly contagious or uncontrollably contagious. Take in consideration how a movie is almost always funnier when watched along side another that laughs really joyfully. It seems that both individuals will encourage the other to laugh harder. This goes the same for watching a violent movie where rage was used liberally. The viewer may be lead into a sense of anger themselves, often leaving the theater all wound up and stressed.

What is interesting is how nearly all vertebrates yawn, but only certain highly socialized animals yawn because of contagion, including all primates, humans (of course) and birds… Why birds? Who the hell knows, but the more I learn about birds the more fascinated I become with them (see this article for more on birds and intelligence). As any multiple dog or cat owner will tell you, dogs or cats don’t make each other yawn. This tells us that there are levels of communication. Some are completely limited to what is encoded into their DNA (bees, ants, fish), some are solely associative (dogs, horses, cats) and a rare few are learned through imitation (primates, humans). Either way, this may be a start to what makes us such a dynamic sociological animal. You can almost see the evolution of communication through the different levels of behavioral perception among the organisms social group. So next time you run into someone and have a strange unconscious feeling about them, thank your mirror neurons for whispering suggestions of how to perceive the other person.