Table of ContentsView AllTable of ContentsTheories to Explain Why We YawnIs Yawning Contagious?Reasons for Yawning in Different SituationsExcessive Yawning

Table of ContentsView All

View All

Table of Contents

Theories to Explain Why We Yawn

Is Yawning Contagious?

Reasons for Yawning in Different Situations

Excessive Yawning

Yawning is considered “contagious” because when you see someone else yawn, it often stimulates you to yawn, too.

This article explains the theories and reasons behind yawning and why it can be contagious.

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A woman yawning in bed

Yawning occurs as early as 12 weeks of fetal life. It is mostly involuntary, and when it begins, it cannot be suppressed.Researchers suggest several theories to explain why we yawn.

Respiration

Yawning may have something to do with a lack of oxygen.Hypoxia(lack of oxygen) is one of the oldest theories as to why we yawn and dates back to 1755.

This theory suggests that yawning is triggered when blood or brainoxygenis insufficient.The belief is that yawning removes “bad air” from the lungs and increases circulation in the brain. However, when experts measure blood oxygen and carbon dioxide, they find little correlation with yawning.

Yawning increases lung capacity and improves blood flow to the heart, benefiting respiration. Researchers also believe yawning repositions muscles to widen the airway, increasing oxygen in organs and tissues.

Arousal

Some believe yawning is anarousaldefense reflex occurring when people are bored or sleepy. Yawning might happen in lower states of consciousness, including the following:

Because yawning seems to occur less often during stimulating activities like cooking, cleaning, and talking, researchers suggest that yawning promotes arousal and associate it with higher brain activation.

Inner Ear Pressure

When you yawn, the pharyngeal end of theeustachiantubeopens and closes, equalizing the pressure in your inner ear and relieving these symptoms.

Body Temperature

Researchers have proposed that yawning cools the brain. This theory emerged after noticing that yawning occurs more often in situations in which internal body temperature rises, such as the following:

A yawn can reduce the symptoms of these chronic conditions. Research has also found that yawning is associated with outdoor air temperature. One study found that yawning occurs more frequently in the summer than in the winter, leading researchers to believe that yawning is involved in maintaining internal body temperature.

Yawning in PetsIn addition to sleepiness, a yawning dog may be indicating stress and indifference.Dogs also exhibit contagious yawning, meaning they yawn in response to human yawns.

Yawning in Pets

In addition to sleepiness, a yawning dog may be indicating stress and indifference.Dogs also exhibit contagious yawning, meaning they yawn in response to human yawns.

Why Do We Yawn After Seeing Someone Else Yawn?

Have you ever seen someone yawn and suddenly have the urge to yawn? Contagious yawns have been observed in humans, other mammals, and some birds. It even occurs across species.This type of yawn emerges in early childhood as children learn social skills and cues.

Emotional ContagionContagious yawning differs from spontaneous yawning because it’s in response to someone else’s yawn. Research is not definitive as to whether this results from emotional contagion (an empathy response to familiar people) because study results have been inconsistent or inconclusive.

Emotional Contagion

Contagious yawning differs from spontaneous yawning because it’s in response to someone else’s yawn. Research is not definitive as to whether this results from emotional contagion (an empathy response to familiar people) because study results have been inconsistent or inconclusive.

Yawning is not fully understood, but many theories exist as to how yawning impacts your body. As a result, you may yawn for different reasons.

1. Boredom

Yawning when bored is common—it keeps the brain awake during passive activities.Your face and neck muscles move when you yawn, which may stimulate thecarotid artery. Researchers believe this could increase heart rate and stimulate hormone release.

2. Feeling Tired (or Not)

Tiredness is probably the reason people associate with yawning most, and with good reason. People yawn when they’re tired because yawning promotes arousal and activates the brain.

In other words, yawning when you’re sleepy is your body’s way of trying to help you stay awake. Similarly, when you first wake up, yawning has the same effect.

3. To ‘Pop’ Your Ears

Chewing gum, swallowing, and yawning are tricks for handling inner ear pressure changes. Though this isn’t spontaneous, you can intentionally yawn or mimic part of a yawn to open the eustachian tube while flying or driving through changing elevations.

4. To Regulate Body Temperature

Because one theory points to yawning as a component of regulating internal body temperature, you may notice that you yawn more if you have a fever or it’s warm outside.

Yawning for Days and Days: What to Do

Rarely, it can also result from certain medicines or problems with the body’s temperature control.

To try and avoid excessive yawning, be sure to:

Usually, excessive yawning is due to inadequate sleep. However, because some health conditions can cause excessive yawning, see a healthcare provider for a diagnosis if you don’t think sleepiness is the cause.

Summary

There are several theories as to why people yawn. These include increasing oxygen to the brain, organs, and tissues, helping you stay awake, relieving inner ear pressure, and regulating body temperature. Yawning is also contagious, though researchers don’t fully understand why people yawn in response to seeing other people yawn.

Excessive yawning is usually the result of too little sleep, but it can also be a sign of an underlying health condition or medication side effect. Healthy sleep habits are an excellent place to start, but see a healthcare provider if it continues.

14 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Dolkart KM.A conjecture as to the physiological origins of yawning.Int J Appl Basic Med Res. 2017;7(2):148. doi:10.4103/2229-516X.205818Dhar DK, Arora R.The mystery behind “yawning”: a physiological insight.Journal of Health and Allied Sciences, 2020;10(2), 57-62. doi:10.1055/s-0040-1714196Walusinski O.Popular knowledge and beliefs. doi:10.1159/000307071Doelman CJ, Rijken JA.Yawning and airway physiology: a scoping review and novel hypothesis.Sleep Breath. 2022;26(4):1561-1572. doi:10.1007/s11325-022-02565-7Gupta S, Mittal S.Yawning and its physiological significance.Int J Appl Basic Med Res. 2013;3(1):11-15. doi:10.4103/2229-516X.112230MedlinePlus.Ear barotrauma.Massen JJM, Dusch K, Eldakar OT, Gallup AC.A thermal window for yawning in humans: yawning as a brain cooling mechanism.Physiol Behav. 2014;130:145-148. doi:10.1016/j.physbeh.2014.03.032American Kennel Club.Why do dogs yawn?Neilands P, Claessens S, Ren I, et al.Contagious yawning is not a signal of empathy: no evidence of familiarity, gender or prosociality biases in dogs.Proc Biol Sci. 2020;287(1920):20192236. doi:10.1098/rspb.2019.2236Gallup AC, Wozny S.Interspecific contagious yawning in humans.Animals (Basel). 2022;12(15):1908. doi:10.3390/ani12151908Massen JJM, Gallup AC.Why contagious yawning does not (yet) equate to empathy.Neurosci Biobehav Rev. 2017;80:573-585. doi:10.1016/j.neubiorev.2017.07.006Summer J, Reiman A.Why do you yawn?The Sleep Foundation.McDonnell A, Pratibhu P, Natteru P, et al.Excessive yawning as an ictal manifestation of post-stroke seizures.Neurology.Apr 2021;96(15):2150.National Library of Medicine.Yawning—excessive.

14 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Dolkart KM.A conjecture as to the physiological origins of yawning.Int J Appl Basic Med Res. 2017;7(2):148. doi:10.4103/2229-516X.205818Dhar DK, Arora R.The mystery behind “yawning”: a physiological insight.Journal of Health and Allied Sciences, 2020;10(2), 57-62. doi:10.1055/s-0040-1714196Walusinski O.Popular knowledge and beliefs. doi:10.1159/000307071Doelman CJ, Rijken JA.Yawning and airway physiology: a scoping review and novel hypothesis.Sleep Breath. 2022;26(4):1561-1572. doi:10.1007/s11325-022-02565-7Gupta S, Mittal S.Yawning and its physiological significance.Int J Appl Basic Med Res. 2013;3(1):11-15. doi:10.4103/2229-516X.112230MedlinePlus.Ear barotrauma.Massen JJM, Dusch K, Eldakar OT, Gallup AC.A thermal window for yawning in humans: yawning as a brain cooling mechanism.Physiol Behav. 2014;130:145-148. doi:10.1016/j.physbeh.2014.03.032American Kennel Club.Why do dogs yawn?Neilands P, Claessens S, Ren I, et al.Contagious yawning is not a signal of empathy: no evidence of familiarity, gender or prosociality biases in dogs.Proc Biol Sci. 2020;287(1920):20192236. doi:10.1098/rspb.2019.2236Gallup AC, Wozny S.Interspecific contagious yawning in humans.Animals (Basel). 2022;12(15):1908. doi:10.3390/ani12151908Massen JJM, Gallup AC.Why contagious yawning does not (yet) equate to empathy.Neurosci Biobehav Rev. 2017;80:573-585. doi:10.1016/j.neubiorev.2017.07.006Summer J, Reiman A.Why do you yawn?The Sleep Foundation.McDonnell A, Pratibhu P, Natteru P, et al.Excessive yawning as an ictal manifestation of post-stroke seizures.Neurology.Apr 2021;96(15):2150.National Library of Medicine.Yawning—excessive.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Dolkart KM.A conjecture as to the physiological origins of yawning.Int J Appl Basic Med Res. 2017;7(2):148. doi:10.4103/2229-516X.205818Dhar DK, Arora R.The mystery behind “yawning”: a physiological insight.Journal of Health and Allied Sciences, 2020;10(2), 57-62. doi:10.1055/s-0040-1714196Walusinski O.Popular knowledge and beliefs. doi:10.1159/000307071Doelman CJ, Rijken JA.Yawning and airway physiology: a scoping review and novel hypothesis.Sleep Breath. 2022;26(4):1561-1572. doi:10.1007/s11325-022-02565-7Gupta S, Mittal S.Yawning and its physiological significance.Int J Appl Basic Med Res. 2013;3(1):11-15. doi:10.4103/2229-516X.112230MedlinePlus.Ear barotrauma.Massen JJM, Dusch K, Eldakar OT, Gallup AC.A thermal window for yawning in humans: yawning as a brain cooling mechanism.Physiol Behav. 2014;130:145-148. doi:10.1016/j.physbeh.2014.03.032American Kennel Club.Why do dogs yawn?Neilands P, Claessens S, Ren I, et al.Contagious yawning is not a signal of empathy: no evidence of familiarity, gender or prosociality biases in dogs.Proc Biol Sci. 2020;287(1920):20192236. doi:10.1098/rspb.2019.2236Gallup AC, Wozny S.Interspecific contagious yawning in humans.Animals (Basel). 2022;12(15):1908. doi:10.3390/ani12151908Massen JJM, Gallup AC.Why contagious yawning does not (yet) equate to empathy.Neurosci Biobehav Rev. 2017;80:573-585. doi:10.1016/j.neubiorev.2017.07.006Summer J, Reiman A.Why do you yawn?The Sleep Foundation.McDonnell A, Pratibhu P, Natteru P, et al.Excessive yawning as an ictal manifestation of post-stroke seizures.Neurology.Apr 2021;96(15):2150.National Library of Medicine.Yawning—excessive.

Dolkart KM.A conjecture as to the physiological origins of yawning.Int J Appl Basic Med Res. 2017;7(2):148. doi:10.4103/2229-516X.205818

Dhar DK, Arora R.The mystery behind “yawning”: a physiological insight.Journal of Health and Allied Sciences, 2020;10(2), 57-62. doi:10.1055/s-0040-1714196

Walusinski O.Popular knowledge and beliefs. doi:10.1159/000307071

Doelman CJ, Rijken JA.Yawning and airway physiology: a scoping review and novel hypothesis.Sleep Breath. 2022;26(4):1561-1572. doi:10.1007/s11325-022-02565-7

Gupta S, Mittal S.Yawning and its physiological significance.Int J Appl Basic Med Res. 2013;3(1):11-15. doi:10.4103/2229-516X.112230

MedlinePlus.Ear barotrauma.

Massen JJM, Dusch K, Eldakar OT, Gallup AC.A thermal window for yawning in humans: yawning as a brain cooling mechanism.Physiol Behav. 2014;130:145-148. doi:10.1016/j.physbeh.2014.03.032

American Kennel Club.Why do dogs yawn?

Neilands P, Claessens S, Ren I, et al.Contagious yawning is not a signal of empathy: no evidence of familiarity, gender or prosociality biases in dogs.Proc Biol Sci. 2020;287(1920):20192236. doi:10.1098/rspb.2019.2236

Gallup AC, Wozny S.Interspecific contagious yawning in humans.Animals (Basel). 2022;12(15):1908. doi:10.3390/ani12151908

Massen JJM, Gallup AC.Why contagious yawning does not (yet) equate to empathy.Neurosci Biobehav Rev. 2017;80:573-585. doi:10.1016/j.neubiorev.2017.07.006

Summer J, Reiman A.Why do you yawn?The Sleep Foundation.

McDonnell A, Pratibhu P, Natteru P, et al.Excessive yawning as an ictal manifestation of post-stroke seizures.Neurology.Apr 2021;96(15):2150.

National Library of Medicine.Yawning—excessive.

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