The function of a yawn has largely been understood as being synonymous with being tired and needing rest, yet yawns are largely contagious and can be triggered even in those who are well rested. What is the scientific reason for such a reaction between people? It's largely due to our brains wanting to mimic a specific action. Sometimes we mirror other people's actions and don't even know it, yet those actions can be much more subtle or understated so they go unnoticed when we start to mimic someone.
A yawn is the body's way of taking in a fresh supply of oxygen. This can be for many reasons but typically when a person is tired, their oxygen levels may have dropped. Stress and anxiety can cause the presence of yawning as well because oxygen levels can be compromised in those situations. Though a person yawning used to be understood only as a sign that a person needs sleep, it is now known as a shift in alertness or boredom as well.
The urge to mimic is something that can be seen in many other ways. If you ever felt the need to laugh from someone else's laughter or cry when you see someone else crying, it's the same type of reaction. Human beings naturally have empathy-adapting techniques that allow us to see what's going on in our general area and potentially cause us to adopt those same ticks, reactions or mechanisms. A study carried out back in 2013, found that children with autism did also yawn more when they were focused on a person's mouth who was yawning. This does away with the notion that only empathy can trigger such reactions. These are social cues that can be understood and adopted even in the case where concentration or empathy may be lacking.
Link Between Humans And Animals
What's even more interesting about the yawn is that this type of reaction is not specific to human beings. When certain animals in the wild have been observed, many are prone to yawning in response to another's yawn. It is often thought to be some type of unspoken, involuntary form of communication between two parties, whether they are human or animal. There is even said to be a correlation between when a human yawns and then their dog proceeds to yawn right after. Some people believe it is a combination of factors and variables that can cause such a reaction. Sometimes visually seeing the other person yawn isn't even a necessary part of what makes the process happen. When speaking on the phone with someone, their yawning can often trigger the same response in the other individual and vice versa.
More than a sign of being tired, the yawn can be a mechanism with which we understand certain things intrinsically - an unspoken sign of many things other than needing a nap or being anxious. It can be a commonality that helps connect individuals through a specific function that seems fairly innocuous. Like many things, a yawn can simply be a sign that ends up filtering through various rooms or environments when just one person has the urge to do it.
Is Yawning Contagious?
Experts at the University of Nottingham published research suggesting that the human propensity for contagious yawning is triggered automatically by primitive reflexes in the primary motor cortex, an area of the brain responsible for motor function. The study – “A Neural Basis For Contagious Yawning” - was published in the academic journal Current Biology.
Their latest findings show that our ability to resist yawning when someone else near us yawns is limited. And our urge to yawn is increased if we are instructed to resist yawning. But, no matter how hard we try to stifle a yawn, it might change how we yawn but it won't alter our propensity to yawn. Importantly, they have discovered that the urge to yawn - our propensity for contagious yawning - is individual to each one of us. Stephen Jackson, Professor of Cognitive Neuroscience, in the School of Psychology, led the multidisciplinary study. He said: "We suggest that these findings may be particularly important in understanding further the association between motor excitability and the occurrence of echophenomena in a wide range of clinical conditions that have been linked to increased cortical excitability and/or decreased physiological inhibition such as epilepsy, dementia, autism, and Tourette syndrome."
Contagious yawning is triggered involuntarily when we observe another person yawn. It is a common form of echophenomena, the automatic imitation of another's words or actions. The neural basis for echophenomena is unknown. To test the link between motor excitability and the neural basis for contagious yawning the Nottingham research team used transcranial magnetic stimulation (TMS). They recruited 36 adults to help with their study. These volunteers viewed video clips showing someone else yawning and were instructed to either resist yawning or to allow themselves to yawn.
The Urge To Yawn
The participants were videoed throughout, and their yawns and stifled yawns were counted. In addition, the intensity of each participant's perceived urge to yawn was continuously recorded. Using electrical stimulation they were also able to increase the urge to yawn. 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 tics and that's what we are working on."
TMS was used to quantify motor cortical excitability and physiological inhibition for each participant and predict the propensity for contagious yawning across all the volunteers. The TMS measures proved to be significant predictors of contagious yawning and demonstrated that each individuals's propensity for contagious yawning is determined by cortical excitability and physiological inhibition of the primary motor cortext. Professor Jackson added: "If we can understand how alterations in cortical excitability give rise to neural disorders we can potentially reverse them. We are looking for potential non-drug, personalized treatments, using TMS that might be affective in modulating inbalances in the brain networks."
Why Does Contagious Yawning Happen?
Why contagious yawning happens remains a mystery. A study at Tohoku University suggests that contrary to common belief that the yawning contagion is associated with empathy, and more likely that perceptual sensitivity is to blame. In the study, healthy volunteers were shown photos and videos of people yawning. The intention was to induce contagious yawning. The participants were observed through hidden cameras, which recorded their reactions, and an eye-tracking machine, which registered their gazing patterns.
To test the participants' sensitivity towards yawning expressions, they were later given 60 photos containing four intensity levels of yawning, and asked to judge if the person in each photo was yawning. For control comparisons, participants were also shown 60 happy and 60 angry photos with four intensity levels, after which they were asked if the people in the photos looked happy or angry. Researchers found that those who were more likely to detect yawning from a face were also more likely to be induced to yawn. However, sensitivity to happy or angry faces appeared to have little relation to the frequency of contagious yawning.
To study whether contagious yawning relates to empathy in healthy people, the participants' autistic tendency - or AQ, autistic quotient measured by an autism-spectrum quotient questionnaire - was measured but showed little effect. However, female participants in the study registered a significantly higher susceptibility towards catching a yawn contagiously. The study, titled "Yawning Detection Sensitivity and Yawning Contagion" was published in i-Perception. It is the first study to investigate the perceptual limitations on yawning contagion behavior in a non-clinical population.
“Recent clinical observations showed that individuals diagnosed with autism or schizophrenia did not yawn contagiously like typical individuals,” says lead researcher, Dr. Chia-huei Tseng, an associate professor at the Research Institute of Electrical Communication (RIEC) at Tohoku University. “This has led many to think that impaired social ability or empathy might contribute to a person's inability to yawn contagiously. However, it is unknown if the clinical speculations also apply to the general population. We find that for a non-clinical population, perceptual ability is more closely related to contagious yawning than empathy is. Since it's been documented that people with autism tend to suffer from impaired perception such as an atypical eye gazing on faces and a difficulty in judging facial emotions, it's possible that their perceptual limitation causes them to be unable to detect someone else's yawning expression. This is a possible explanation for their lack of contagious yawning."
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Lisa S. Jones is a certified nurse, nutritionist, fitness coach and health expert. Her training credentials include a B.Sc. in Nursing from California State University in 2013 and Youth Nutrition Specialist Certification from the American Fitness Professionals and Associates in 2015. In 2017, she also received Holistic Nutrition Certification from the American Fitness Professionals and Associates.
Founder Ray Spotts has a passion for all things natural and has made a life study of nature as it relates to health and well-being. Ray became a forerunner bringing products to market that are extraordinarily effective and free from potentially harmful chemicals and additives. For this reason Ray formed Trusted Health Products, a company you can trust for clean, effective, and healthy products. Ray is an organic gardener, likes fishing, hiking, and teaching and mentoring people to start new businesses. You can get his book for free, “How To Succeed In Business Based On God’s Word,” at www.rayspotts.com.
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