Buzz
What exactly is yawning, and why do we do it so frequently? Neuroscientist and yawning authority Robert Provine describes it as "ancient and autonomic." It has roots in our evolutionary past and is observed across a variety of species—even fish exhibit it. It's autonomic because it originates from the brainstem, the brain's deepest level, where certain automatic responses are ingrained to the point that they don't even count as reflexes.
Yawning can be triggered by a range of factors such as boredom, tiredness, and temperature changes. A 2014 study proposed the idea of a "thermal window" (around 68°F) for human yawning; as the surrounding temperature nears body temperature or drops close to freezing, we yawn less. The study suggests that yawning might be a way to regulate brain temperature. This differs from the common belief that we yawn to intake more oxygen, as current evidence indicates that isn't the case. It may actually serve to bring in cool, soothing air through the nose and mouth to help manage brain heat.
THE YAWN EFFECT?
Over time, researchers have documented "contagious yawning" in species such as chimpanzees, humans, baboons, bonobos, wolves, and even dogs to a certain extent. Yawning feels pleasant, so it's no surprise that we might yawn along with someone else. However, you're not truly "joining in" consciously—it's an automatic response. If you become aware of your yawn, it may stop.
While many previous studies have observed this behavior, a newer study published in the journal Adaptive Human Behavior and Physiology challenges the idea that yawns are contagious—or at least, that we've definitively proven it. Experimental psychologist Rohan Kapitány from the University of Oxford reviewed the existing research on contagious yawning and found minimal conclusive evidence to support the belief that yawns are truly contagious.
"The idea that yawns are contagious seems obvious," Kapitány explained to PsyPost, "but there are some fundamental reasons why we might be wrong about this. If we don't critically examine what we think we know, we could arrive at conclusions that don't reflect reality. In this case, the literature hasn't questioned the core assumptions about contagious yawning, leading to a range of inconsistent methodologies and results."
Despite this, Kapitány's study was small and limited, and he, along with his co-authors, encourages other researchers to test their conclusions with their own experiments.
"I could be wrong!" Kapitány remarked. "Maybe yawns are contagious!" He expressed a desire for "more thorough" efforts to disprove the claim that yawns are contagious, rather than "merely repeating the same demonstration in slightly different settings with increasingly detailed explanations."
WHO DOESN'T YAWN ALONG?
Certain individuals with autism or schizophrenia don't seem to respond to contagious yawning. The same is true for children under the age of four. This observation has sparked various theories connecting yawning with empathy and the brain's mirror-neuron system (MNS). The hypothesis suggests that deficits in the MNS could prevent people from picking up on subtle empathetic signals that typically trigger yawns. Brain scans, such as fMRIs, show that other brain regions also react to yawning images, potentially more so than areas linked to empathy.
THE YAWNING RESPONSE
The amygdala, a brain region connected to fear and heightened awareness, is activated when we see someone yawn. We sometimes yawn when we're anxious, such as before a big performance.
Perhaps we yawn during these moments to prepare our brains for "fight or flight" mode. If contagious yawning is an adaptive evolutionary trait, it may have been a way to quickly ready an entire group of humans for action in response to threats. (If this theory holds, older individuals might have been less susceptible to contagious yawns.) As social mammals, this evolutionary refinement—turning ordinary yawning into contagious yawning—could have helped groups survive in the face of danger.
Or maybe it’s a lot simpler than we think. Laughing, which also feels good, can be contagious too. Just like laughter, contagious yawning could be a way for groups to bond—showing a relaxed, unguarded sleepiness. It might be more about creating a sense of safety than signaling a threat.
THE SLOW STARTERS AND THE IMITATORS
Contagious yawning remains somewhat of a scientific enigma. We love to hypothesize about it and search for the definitive cause. But why should an evolutionary trait have a singular purpose? Traits often persist because they serve multiple functions. In other cases, they’re evolutionary remnants whose original role has faded, but since they don’t interfere with survival, there’s no drive to eliminate them.
A modern twist on yawning is the less contagious—fake yawning. You might use this tactic as a subtle way to indicate that a conversation has gone on too long. Why not try a little experiment next time you're in a meeting with your boss? Sit back, yawn, and observe if they yawn back. Perhaps you’ll make a new discovery... though don’t count on a promotion.
