Why is Yawning Contagious?

By jennifer

Reviewed: dr. vanta

Article Sources

Article Sources

• 1. Rundle, Brian K., et al. 'Contagious Yawning and Psychopathy.' Personality and Individual Differences, Pergamon, 5 June 2015, www.sciencedirect.com/science/article/abs/pii/S0191886915003645
• 2. Carey, Teresa. 'Why Are Yawns Contagious? We Asked a Scientist.' PBS, Public Broadcasting Service, 17 July 2018, www.pbs.org/newshour/science/why-are-yawns-contagious-we-asked-a-scientist#:~:text=What is known is that,imitate the actions of others
• 3. AC;, Massen JJ;Dusch K;Eldakar OT;Gallup. 'A Thermal Window for Yawning in Humans: Yawning as a Brain Cooling Mechanism.' Physiology & Behavior, U.S. National Library of Medicine, pubmed.ncbi.nlm.nih.gov/24721675/
• 4. Norscia, Ivan, et al. 'Auditory Contagious Yawning Is Highest Between Friends and Family Members: Support to the Emotional Bias Hypothesis.' Frontiers in Psychology, Frontiers Media S.A., 3 Apr. 2020, www.ncbi.nlm.nih.gov/pmc/articles/PMC7147458/
• 5. Nahab, Fatta B. 'Exploring Yawning with Neuroimaging.' Frontiers of Neurology and Neuroscience, U.S. National Library of Medicine, 2010, www.ncbi.nlm.nih.gov/pmc/articles/PMC4041699/
• 6. Featured Neuroscience Psychology, May 22, 2018, et al. 'Why Do We Yawn and Why Is Yawning So Contagious?' Neuroscience News, 22 May 2018, neurosciencenews.com/yawning-contagious-9112/
• 7. St. Louis Public Radio | By Eli Chen. 'Contagious Yawning, Laughing and Scratching Gives Clues to How the Human Brain Works.' St. Louis Public Radio, 27 Mar. 2017, news.stlpublicradio.org/health-science-environment/2017-03-25/contagious-yawning-laughing-and-scratching-gives-clues-to-how-the-human-brain-works
• 8. 'Yawning: Causes and Reasons for Contagious Yawning.' Medical News Today, MediLexicon International, www.medicalnewstoday.com/articles/318414#Can-one-yawn-too-much

Medical Expert

More About Us

Yawning is such a common occurrence that people may not always think about why they're doing it. It's usually considered a sign that someone is tired or bored. But that's not the only reason people yawn. Sometimes people yawn not because they feel fatigued, but because they witness someone else yawning.

This is what's known as contagious yawning, and it may be triggered by someone who's nearby or even by watching a video of people yawning.¹Rundle, Brian K., et al. ‘Contagious Yawning and Psychopathy.’ Personality and Individual Differences, Pergamon, 5 June 2015, www.sciencedirect.com/science/article/abs/pii/S0191886915003645 For some people, simply thinking about yawning may be enough to trigger it.

Why Do Humans Yawn?

It's not known exactly why humans yawn, but there are theories. People yawn when they're tired, bored or when someone else is yawning nearby. There may also be physiological reasons for yawning.

Some scientists think yawning may be related to breathing. A yawn brings in oxygenated air and quickens the heartbeat, which may be helpful when a person is drowsy and taking more shallow breaths.²Carey, Teresa. ‘Why Are Yawns Contagious? We Asked a Scientist.’ PBS, Public Broadcasting Service, 17 July 2018, www.pbs.org/newshour/science/why-are-yawns-contagious-we-asked-a-scientist#:~:text=What is known is that,imitate the actions of others Yawning may also help cool the brain. Inhaling air and speeding up the heart rate causes blood to circulate through the body faster, in turn, cooling the brain.³AC;, Massen JJ;Dusch K;Eldakar OT;Gallup. ‘A Thermal Window for Yawning in Humans: Yawning as a Brain Cooling Mechanism.’ Physiology & Behavior, U.S. National Library of Medicine, pubmed.ncbi.nlm.nih.gov/24721675/ Yawns may also have evolved as a communication tool.