Even thinking about yawning can cause you to do it. There are many theories as to why people yawn. One popular theory is that yawning helps your body bring in more oxygen. But this theory has been mostly debunked. Keep reading to see what current research suggests yawning says about you, your brain temperature, and your potential for empathy.
The most scientifically backed theory about why we yawn is brain temperature regulation. Another reason you may yawn is because the body wants to wake itself up.
The motion helps stretch the lungs and their tissues, and it allows the body to flex its muscles and joints. It may also force blood toward your face and brain to increase alertness. Yawning is definitely contagious. Even videos of people doing it can trigger a yawning session.
Try watching the video below and see if you end up yawning. The study, published in the journal Personality and Individual Differences, looked at college students, their personalities, and how they reacted to different facial movements. The results showed that the less empathy a person had, the less likely they would yawn after seeing someone else yawn.
For instance, having an ice pack on one's forehead might itself be responsible for the arousal effect while a warm pack would tend to induce relaxation and drowsiness. Thus, it is not possible to distinctly distinguish between the effects of temperature and sleepiness in this study. The physiological consequences of yawning are analogous to those which are needed to effectively cool the brain, such as increase in the peripheral and cerebral blood flow.
The gaping of mouth and deep inhalation of cool air during a yawn also alters the temperature of blood going from the lungs to the brain via convection.
Tearing from the eyes, which some people experience, at the peak of yawn may likewise play a role in dissipation of heat from skull. Patients with clinical disorders such as multiple sclerosis, epilepsy, migraine, stress, anxiety, head trauma, and stroke experience excessive yawning which is followed by temporary cessation of their symptoms.
This is because these conditions lead to an increase in the body core temperature, thereby resulting in abnormal thermoregulation, which the body then tries to correct transiently by way of yawning.
Yawning has a well-known contagious effect in humans and this effect is now frequently used to induce yawning for research purposes. The susceptibility to contagious yawning correlates with empathic skills in healthy humans. Millen and Anderson[ 25 ] conducted a two part study on infants and preschool children to investigate whether they also showed susceptibility to contagious yawning like older children and adults or not.
In the first part of the study, 20 mothers were asked to record the occurrence, time, and context of every yawn that occurred in their children aged months on a logbook, over a 1 week period. A total of eight logs were returned and analyzed. It was observed that the most common context of yawns was on awakening after morning or afternoon naps Furthermore, none of the mothers made any reference to any possible contagious yawning episode.
In the second part of study, 22 infants and toddlers were observed for contagious yawning while viewing the video clips of their yawning mothers. These clips were inserted within a series of images of unfamiliar individuals who were either smiling or yawning. It was seen that 16 children did not yawn at all throughout the entire study, while two children yawned once during the presentation and the rest of the four children yawned once, post-presentation.
On the basis of these observations, the authors proposed that infants and preschool children appear largely immune to contagious yawning, even if the stimulus is an emotionally significant one. This is in marked contrast to older children and adults. The small data group analyzed was recognized as a major limitation in this study by the authors.
The latter also maintain that some discrepancies might also have arisen if the parents may have missed some of their child's yawns.
Therefore, contagious yawning can be induced in children only after years of age, as below this age group, the neural mechanisms required to understand the mental state of others are still under development. Extensive evidence indicates that the susceptibility of contagious yawning is reduced in patients who are suffering from disorders that affect the ability of social interaction.
On comparing the results with those obtained in an age and sex matched group of healthy controls, they observed that schizophrenic individuals showed significantly lower contagion rates for yawning as well as laughter. Similarly, in another study carried out by Senju et al. Both groups were observed closely while viewing yawning videos or control video clips of mouth opening in a random sequence.
Different neuroimaging studies also support the empathic basis of contagious yawning. Significantly higher functional magnetic resonance imaging activations in response to contagious yawning have been observed in posterior cingulated area,[ 24 ] bilateral superior temporal sulcus[ 29 ] or venteromedial prefrontal cortex.
Recently, the mirror neuron system of the brain, a collection of neurons in the right posterior inferior frontal gyrus has been suggested to be involved in contagious yawning.
The results of a study conducted by Norscia and Palagi[ 33 ] have provided evidence for the fact that the social bond associated with empathy affects the yawn contagion in humans in terms of occurrence, frequency and latency. A total of bouts of yawning were observed, out of which only were analyzed, since only they could be definitely assigned as being triggered in an observer by a specific audio-visual contact with a yawner, within a 3 min time slot.
The importance of the social bond in shaping the yawn contagion demonstrates that empathy and yawning are strongly correlated. The link between empathy and contagious yawning is further supported by the data collected by Campbell and de Waal. The ingroup videos were shown before the outgroup videos to all the subjects. It was ensured that all the subjects paid similar attention to both types of videos.
Each chimpanzee was exposed to the videos for a total of 20 min on one or more days, depending upon his interest and cooperativeness, to eliminate the effect of stress. Also, none of the test subjects were able to see the other chimpanzees while viewing the videos. Even though, the authors do maintain that their results suggest a possible relationship between yawning and empathy, yet they also admit a few limitations of their study. This may be due to the fact these animals are territorial and form small coteries, which are aggressive to neighboring ones.
Such a kind of behavior is absent in humans since the latter do not always view strangers as belonging to an outgroup. It is thus concluded that yawning may be a part of action repertoire of empathic and communicative processes in adult humans and some other mammals which provide for a strong social role of yawns in these species. Yawning relieves the ear discomfort and hearing problems that are commonly experienced by people during rapid altitude changes in airplanes and elevators.
This is achieved by opening of the eustachian tubes due to the contraction and relaxation of tensor tympani and stapedius muscles. An crucial experimental evidence that provides support to the above proposition comes from the work of Winther et al. The contrast material was detected in middle-ear by computerized tomographic scan of the temporal bone.
However, almost paradoxically, it is theorized that yawning is not a sign of sleepiness or boredom, but actually a reflex that your brain induces to wake you up or make you more alert. Yawning is associated with some hormones that are released that briefly increase the heart rate and alertness. I suppose this is an evolutionary response related to a time where if one were asleep or inattentive something bad might happen to you! Related to arousal is the common phenomenon of yawning upon awakening after sleep or nap.
This is further evidence that yawing is a stimulation and arousal reflex rather than the opposite. A final theory on the cause of yawning is that it is a reflex that helps cool a warm brain. This is unproven and although there are some examples of yawning in heat related scenarios, yawing is not something we see when playing sports or playing in the sun.
Physiologically, deep breaths and open mouths can cool the brain slightly, but the evidence that this is a real cause of yawning is not convincing. Your doctor will eliminate general causes such as sleep deprivation and medication, before probing further with tests such as an electroencephalogram EEG to determine electrical activity in the brain, or an MRI Scan to determine heart function or access other parts of the body such as the spinal cord.
If a serious problem is detected, immediate treatment will be prescribed. Adapted from an article by Dr. If you have diabetes, make sure you pay extra attention to your feet because imbalances in blood sugar levels will weaken them.
Your mouth opens wide, you inhale a lot of air, your lungs fill up, and then you exhale… When you yawn, you: stretch your eardrums; close your eyes tight enough to make them water; release a rush of oxygen into your blood that clears out toxins; cool the brain by stretching the jaw and increasing circulation in the face and neck. Why do you yawn?
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