Why is yawning contagious?
Have you ever yawned at the sight of or upon hearing another person yawn, even over the phone?
Oh yes, the mere sight of another person yawning causes many people to open their mouths wide in mimicry. It is like a challenge of “You yawn; I yawn.”
Have you ever tried finding out why it is so? According to scientists, it is likely that all vertebrates yawn spontaneously to regulate inner body processes and yawning can be contagious.
Wikipedia defines yawning as an involuntary reflex action of opening the mouth wide and inhaling deeply, usually due to tiredness or boredom.
Yawning can be contagious among primates such as chimpanzees, wild and domestic cats, dogs and humans.
Medically, contagious yawning is referred to as echophenomena. A contagious yawning is, therefore, one of the copycat behaviours observed among humans.
A behaviour is termed copycat when an individual imitates or adopts the behaviour or practices of another.
Some yawns are short, and some last for several seconds before an open-mouthed exhale. Watery eyes, stretching, or audible sighs may accompany yawning.
Types and benefits
Clinical researchers often classify yawns into two types.
A yawn that occurs on its own is called spontaneous yawning, and a yawn that occurs after seeing someone else do it, is referred to as contagious yawning.
In human and non-human primates, however, two other different types of yawns are generally distinguished according to the physiological state and social context. These are true or rest yawns and tension or aggressive yawns. True yawns are typically associated with states of drowsiness and relaxation (sleepiness or boredom).
On the other hand, tension or aggressive yawns occur in conflict situations and may indicate arousal.
In contrast to this dichotomous view, Altmann (1967) suggested that both types of yawns may indicate levels of physiological arousal and, therefore, it is extremely difficult to disentangle the two, based on the stimuli or context triggering them.
Regarding benefits of yawns, it has been empirically established that yawning can increase blood flow to the brain through the jaw stretching and the deep inhalation of air, replacing warmed blood in the brain with cooler blood from the heart.
This tends to allow heat exchange with the ambient air, which is almost always cooler than body temperature.
Suffice to say that yawning helps us bring more oxygen into the blood and move more carbon dioxide out of the blood.
Yawning also stretches the muscles and joints, increases the heart rate, and may prepare the body for an increased level of alertness. It equally relieves ear discomfort especially due to pain or discomfort emanating from a change in altitude.
Yawning is triggered under a variety of contexts and neurophysiological changes. It primarily occurs during periods of state change, commonly following transitions of sleeping and waking. Scientific research suggests that yawns are initiated alongside increases in cortical arousal, so yawns themselves may function to promote alertness.
Specifically, therefore, tiredness, hunger, boredom, sleepiness and stress tend to make people yawn more than when they in a relaxed mood. However, people who are not tired, bored, stressed, or hungry among others can contagiously yawn just because they see others yawning.
Excessive yawning may also emanate from taking in too much caffeine or going through an opiate detox. However, it may equally be caused by other health conditions or may be attributable to certain health conditions such as heart attack, epilepsy, neurological disorders, liver failure and brain tumour among others.
Should you seek for medical explanation for excessive yawning, a doctor may first ask you about any medications you take as well as your sleep habits, and whether or not you have certain diseases related to excessive yawning.
If sleep issues can be ruled out, a doctor may perform diagnostic tests to find another possible cause for excessive yawning. An electroencephalogram (EEG) is one of the tests that may be done to unearth the cause of the excessive yawning. An EEG measures the electrical activity in the brain and helps diagnose certain conditions that may affect the brain. However, should yawning occur as result of prolonged fatigue, it dissipates once the affected person has had adequate rest.
If excessive yawning is a symptom of a serious medical condition, such as epilepsy or liver failure, then the underlying problem must be treated immediately.
Some American evolutionary biologists such as Andrew Gallup subscribe to a school of thought that contends that yawning probably arose with the evolution of jawed fishes about 400 million years ago. Gallup and Meyers (2021), for example, reported that there is some empirical evidence for how contagious yawns might have evolved to keep us safe.
Have you dared to find out why you yawn just because you see or hear someone else yawned? Well, as already indicated, yawning can be contagious as a person may mimic the yawning of another person who yawns.
Researchers contend that contagious yawning may have evolved to synchronise group behaviour. They equally argue that yawns often cluster during certain times of the day that coincide with transitions and activity. It also may have evolved to increase vigilance within a group.
The basic rationale is that if yawning is an indicator that one individual is experiencing diminished arousal, then seeing another person yawn might, in turn, increase the observer’s vigilance to compensate for the low vigilance of the yawner. The spreading throughout the group of contagious yawns might then increase the vigilance of the entire group.
Yawning can be good for health and at the same time yawing excessively may be due to certain disease conditions pointed out herein. It is also true that yawning is contagious hence sometimes we yawn out of mimicry just because we see or hear another person yawn in a group or during a conversation. In case of excessive yawning, one may see a doctor for appropriate clinical intervention.
The writer is a health service administrator,