Why Do We Automatically Yawn When Someone Else Yawns?

Someone sitting across the room yawns.

A few seconds later, you feel it.

Your jaw begins to loosen.

Your mouth opens.

You take a long breath.

You yawn too.

Sometimes it happens even faster when the person beside you yawns.

And strangely, you do not always need to see an actual yawn.

Hearing someone yawn can be enough.

Watching a video can trigger it.

Reading repeatedly about yawning may even make you feel the urge right now.

This phenomenon is called contagious yawning, and although almost everyone recognizes it, scientists still do not have one complete explanation for why it happens.

Research suggests that contagious yawning involves a mixture of:

social attention;

automatic imitation;

motor-system excitability;

perception of other people’s behavior;

and possibly emotional or physiological synchronization.

What scientists are much less certain about is the famous claim that contagious yawning proves someone is highly empathetic.

That theory became enormously popular.

The evidence is much more complicated.

A major scientific review examining studies of contagious yawning and empathy concluded that the relationship remains inconsistent and inconclusive. The review published in Neuroscience & Biobehavioral Reviews found that differences in empathy scores, familiarity, neurological conditions and brain activity do not yet support the simple claim that people who “catch” yawns are automatically more empathetic.

So why do we yawn when someone else does?

The best answer appears to begin with a remarkably social brain that constantly observes other people and prepares our own bodies to respond.

Contagious Yawning at a Glance

Question	What Research Suggests
Can seeing someone yawn trigger a yawn?	Yes
Can hearing a yawn trigger one?	Yes
Can reading or thinking about yawning trigger the urge?	Sometimes
Is contagious yawning deliberate?	Usually not
Does everyone catch yawns?	No
Does susceptibility vary between people?	Yes
Does it appear in very young children?	Less consistently
Is empathy the proven explanation?	No; evidence is mixed
Does the motor cortex matter?	Research suggests it does
Does resisting stop the urge?	It may change expression but can increase the urge
Do other animals show yawn contagion?	Evidence exists in several species
Is the ultimate evolutionary function known?	Not yet

The important phrase is not yet.

Contagious yawning is real.

Its exact purpose remains under investigation.

1. Your Brain Automatically Pays Attention to Other People’s Actions

Human beings constantly monitor one another.

You notice:

facial expressions;

eye direction;

body posture;

voice;

movement;

and emotional reactions.

Most of this happens without deliberate effort.

If someone suddenly looks frightened, you may turn around before consciously deciding why.

If a group starts laughing, you immediately wonder what happened.

If someone speaks quietly, you may lower your own voice.

Humans are deeply social animals, and our nervous systems are extremely sensitive to signals produced by other humans.

Contagious yawning appears to use some of this same machinery.

Brain-imaging experiments show that watching yawns activates regions involved in processing socially meaningful biological movement.

One fMRI study found yawn-specific activity in the superior temporal sulcus, a brain region strongly involved in interpreting other people’s movements and social cues. The NeuroImage study compared videos of yawns with other mouth movements and found distinct patterns of activation.

Another imaging experiment reported activity in regions including the posterior cingulate cortex and precuneus, areas connected with self-related and social processing. That study on contagious yawning and the brain helped fuel early theories connecting yawning with social cognition.

The basic lesson is clear.

When you see someone yawn, your brain is not simply recording:

“That person’s mouth opened.”

It is processing a familiar biological action performed by another individual.

Sometimes your own body follows.

2. Contagious Yawning Is Partly an Automatic Motor Response

Seeing an action can prepare your own motor system to perform something similar.

This does not mean you automatically copy everything around you.

But perception and movement are closely connected.

A particularly interesting experiment used transcranial magnetic stimulation, or TMS, to measure excitability in the motor cortex while participants watched other people yawning.

Researchers found that differences in cortical excitability and physiological inhibition predicted how susceptible people were to contagious yawning.

Together, those measures accounted for roughly half of the variation observed among participants in that experiment. The study published in Current Biology provides some of the strongest physiological evidence that motor-system properties contribute to yawn contagion.

In other words, your tendency to catch a yawn may depend partly on how readily your motor system moves from:

seeing the action

to

feeling the urge to perform the action.

That makes contagious yawning resemble other forms of behavioral contagion.

Humans sometimes unconsciously mirror:

facial expressions;

posture;

gestures;

speech rhythms;

and laughter.

The News Ink’s article on emotional attachment to objects explores another example of how human brains attach emotional and social meaning to things that appear simple from the outside.

Yawning takes that automatic social responsiveness into the body itself.

3. Trying Not to Yawn Can Make the Urge Feel Stronger

Here is one of the strangest findings.

Imagine watching someone yawn while being told:

Do not yawn.

You might assume conscious control would remove the contagious response.

It does not work that cleanly.

In the TMS experiment mentioned above, researchers asked participants either to allow yawning or actively resist it.

Trying to suppress the yawn changed how people expressed the response.

Some produced stifled yawns rather than full ones.

But resisting also increased the urge to yawn.

That is remarkably familiar.

It is similar to being told:

Do not scratch an itch.

Do not think about blinking.

Do not think about yawning.

Suddenly the sensation becomes harder to ignore.

This suggests contagious yawning involves more than a conscious decision to imitate somebody.

The urge can arise before deliberate control becomes involved.

You can sometimes suppress the movement.

Suppressing the underlying impulse is harder.

4. You Do Not Even Need to See the Yawn

Visual contagion is the most familiar version.

But it is not the only one.

Researchers have shown that hearing yawns can also provoke contagious yawning.

A study specifically examining auditory yawn contagion found that sound alone can generate the response. The auditory contagious-yawning experiment supports the idea that the brain recognizes yawning across different sensory channels.

Scientific reviews have also described yawning triggered by:

watching;

hearing;

reading about;

or thinking about yawns.

That may explain why an article about contagious yawning can itself become slightly dangerous to read without yawning.

You are repeatedly seeing words associated with:

opening the mouth;

deep inhalation;

sleepiness;

and yawns.

The sensory signal may be indirect.

The concept is still being activated.

5. Not Everyone Is Equally Susceptible to Contagious Yawning

If you rarely catch someone else’s yawn, that does not mean anything is necessarily wrong.

People vary substantially.

One large study tested 328 people using videos of yawns and found that individuals differed considerably in their susceptibility to contagious yawning.

More interestingly, those differences were relatively stable.

People who were highly susceptible in one test tended to remain susceptible later.

Those who rarely responded tended to remain less responsive.

Researchers tested possible explanations including:

empathy;

sleepiness;

time of day;

intelligence;

and emotional contagion.

Most explained surprisingly little.

Age had the strongest relationship identified, with older participants somewhat less likely to contagiously yawn.

But even age explained only about 8% of the variation.

The researchers concluded that most individual differences remained unexplained. The Duke-associated study suggests that yawn susceptibility may be a fairly stable personal characteristic whose biology is still not fully understood.

So if one person yawns immediately while another person sits unaffected, science cannot yet explain the entire difference.

6. Contagious Yawning Develops During Childhood

Babies yawn.

Young children yawn.

But spontaneous yawning and contagious yawning are not identical.

Developmental research suggests the contagious response becomes much clearer as children grow.

A study involving 120 children aged one to six found a substantial increase in contagious yawning around age four. The Child Development study suggested that the timing overlaps with major changes in children’s social awareness.

That observation initially encouraged theories connecting contagious yawning with:

theory of mind;

perspective-taking;

social cognition;

and empathy.

But development is complicated.

A four-year-old also differs from a one-year-old in:

attention;

face processing;

language;

social experience;

ability to follow experimental instructions;

and many other ways.

So the developmental timing does not prove that empathy is the cause.

It shows that the response appears to mature alongside other parts of social cognition.

The Autism Evidence Requires Extra Care

Early studies reported lower rates of contagious yawning among some autistic children.

That result was often presented in popular media as evidence that autistic people have “less empathy.”

That conclusion is much too simplistic.

Differences in attention to faces, experimental conditions, sensory processing or social cues can influence whether somebody notices the triggering yawn in the first place.

And the broader scientific literature connecting contagious yawning to empathy is inconsistent.

Using whether someone yawns as an informal “empathy test” is therefore scientifically unjustified.

A person who does not yawn after seeing you yawn has not failed a compassion exam.

7. Is Contagious Yawning Really About Empathy?

This is the biggest question—and the most misunderstood.

There are reasons scientists considered empathy.

Some observational studies found stronger yawn contagion between socially close individuals.

Certain brain regions activated during contagious yawning overlap with networks involved in social cognition.

Some experiments have found relationships between yawning and particular measures of social behavior.

For example, a 2018 laboratory study involving more than 500 participants across two experiments reported an association between contagious yawning and measures of empathy. The Journal of Experimental Psychology research contributed evidence in favor of a connection.

But other research finds little or no relationship.

A 2023 study examining contagious yawning, smiling and several measures of social cognition found no difference in self-reported trait empathy between contagious yawners and non-yawners, although other social-behavior relationships appeared. The 2023 study again showed why the phenomenon does not reduce to one psychological trait.

The most comprehensive critical review concluded that the overall evidence linking contagious yawning directly to empathy remains inconsistent.

So what should we say?

Not:

“You yawn because you are empathetic.”

Better:

Contagious yawning is socially influenced and may overlap with mechanisms involved in emotional or behavioral synchronization, but empathy alone does not currently explain it.

That is scientifically much safer.

8. Familiarity May Influence the Response—but Not Always

Imagine three people yawn:

your partner;

a coworker;

a complete stranger.

Would your brain respond differently?

Some naturalistic studies suggest yes.

Research comparing humans and bonobos found greater yawn contagion between strongly bonded individuals in some settings. A comparative study of humans and bonobos reported stronger responses among individuals with close social relationships.

Other animal studies have produced similar suggestions.

But this area remains methodologically difficult.

People naturally spend more time looking at those they know.

Close individuals may be physically nearer to each other.

Attention differs.

Experimental videos may produce different results from natural social interaction.

Recent work in bonobos has even shown that different experimental methods can lead to different conclusions about which social factors affect yawn contagion.

So familiarity may matter.

It should not be treated as a universal law of contagious yawning.

9. Other Animals Catch Yawns Too

Humans are not the only species in which researchers have reported contagious yawning.

Evidence has been found in several social animals, including some:

chimpanzees;

bonobos;

dogs;

and other species under particular experimental conditions.

That is fascinating because it suggests the phenomenon may have deeper evolutionary roots than human language or culture.

Dogs provide an especially interesting example.

Studies have reported dogs yawning in response to human yawns, including auditory yawns.

One experiment found dogs responded more strongly to familiar human yawns than unfamiliar ones, though researchers emphasized that the underlying mechanism was not definitively established. The canine auditory-yawning study examined whether social familiarity affected the response.

An even stranger 2022 human study found participants could show yawn contagion after watching yawns from a range of non-human animals—including species very distantly related to humans. That interspecies contagious-yawning experiment suggests the triggering mechanism may recognize the broad form of a yawn rather than requiring an identical human face.

So the response may be less about copying a specific person and more about recognizing a characteristic biological action.

Why Would Contagious Yawning Evolve?

Now we enter more speculative territory.

Scientists have proposed several ideas.

Group Synchronization

Yawning might help synchronize states such as:

rest;

sleepiness;

activity transitions;

or vigilance.

If one member of a social group begins shifting toward rest, yawning could help transmit that state.

Behavioral Coordination

Social animals benefit from coordinating:

sleep;

movement;

feeding;

and alertness.

A contagious behavior might help groups shift together.

Vigilance

Some researchers have proposed that yawning and its contagion could help regulate arousal or attention during periods of changing vigilance.

Emotional Contagion

Another possibility is that contagious yawning represents a simple form of sharing another individual’s internal state.

None of these explanations has been established as the single definitive evolutionary purpose.

That is worth emphasizing.

Evolutionary stories can sound convincing even when evidence is incomplete.

What Is a Normal Yawn Actually For?

This question sounds easier.

It is not.

Humans have been trying to explain ordinary yawning for centuries.

Older explanations suggested yawning happens because the body needs more oxygen.

That idea remains widespread.

It is not well supported.

Yawning does not appear simply to be the body’s emergency response to low oxygen.

Several other hypotheses have been proposed.

Arousal and State Change

Yawning frequently occurs around transitions between:

sleep and wakefulness;

boredom and activity;

rest and movement.

It may be associated with shifting arousal states.

Communication

Some researchers argue that yawning can function as a social signal communicating tiredness, boredom or changing vigilance.

A major review of competing theories concluded that evidence for yawning as a communicative signal had gained more support than many older physiological explanations. The review “Why do we yawn?” also emphasized how much remains unresolved.

Brain Cooling

Another influential hypothesis proposes that yawning helps regulate brain temperature.

Research reviews have argued that jaw stretching, changes in blood flow and inhalation of ambient air could contribute to thermoregulation. A review of yawning and thermoregulation presents the case for this hypothesis.

However, scientists continue debating the relative importance of these explanations.

The honest answer is:

We understand the circumstances associated with yawning better than we understand its single ultimate function.

That uncertainty makes contagious yawning even more interesting.

We are trying to explain why one person automatically copies a behavior whose original biological purpose is itself still debated.

Why Do We Yawn More When Tired?

Yawning is strongly associated with transitions in arousal.

People commonly yawn:

before sleep;

after waking;

during boredom;

during monotonous tasks;

or when fatigue increases.

That does not mean every yawn proves you need sleep immediately.

But sleep pressure and changing alertness are common contexts.

This also explains why contagious yawning can spread through a tired room.

Imagine ten students sitting through a late lecture.

One yawns.

Several others are already physiologically close to yawning.

Seeing the first yawn may provide the final trigger.

The effect could therefore reflect both:

the social stimulus

and

the receiver’s existing internal state.

That is a useful way to think about many contagious behaviors.

Another person’s action does not necessarily create your state from nothing.

It can amplify a response your brain was already prepared to produce.

The News Ink’s Healthy Lifestyle guide discusses how sleep, routine, physical activity and recovery interact with alertness more broadly.

Can Thinking About Yawning Make You Yawn?

Possibly.

And if you have yawned during this article, you have just demonstrated the problem researchers face.

Studies and reviews describe yawning as being triggerable by:

seeing;

hearing;

reading;

or even thinking about yawns.

The idea alone can activate the relevant mental representation.

This resembles other body sensations.

Read about itching and you may suddenly notice an itch.

Talk about blinking and you become aware of blinking.

Focus on your breathing and an automatic process becomes conscious.

The brain continuously filters bodily sensations.

Attention can make some of them dramatically more noticeable.

The News Ink’s article on why years feel shorter as we get older explores a related principle: attention and memory can profoundly alter subjective experience even when the underlying physical world has not changed.

With contagious yawning, attention may help transform another person’s yawn into your own bodily urge.

Is It Connected to Mirror Neurons?

You will often hear this explanation:

“Mirror neurons make us yawn when other people yawn.”

That is possible as part of a broader perception-action system, but the statement is too confident.

Mirror neurons were originally identified in monkeys as cells that respond both when an animal performs an action and when it observes an action.

The concept later became popular as an explanation for:

imitation;

empathy;

language;

social understanding;

and contagious behavior.

But human social behavior is produced by distributed networks, not one magical group of neurons.

Research on contagious yawning implicates social-processing regions and motor excitability, but scientists have not established a simple equation:

mirror neurons = contagious yawning.

The motor-cortex findings are especially interesting because they provide measurable physiological evidence for an action-perception link without requiring that every effect be labeled “mirror neurons.”

Why Doesn’t Everyone Yawn Every Time?

Because the response is probabilistic, not automatic in the strict sense.

Seeing a yawn increases the likelihood or urge.

It does not guarantee a yawn.

Factors may include:

individual susceptibility;

attention;

fatigue;

age;

context;

how clearly the yawn is perceived;

and the current state of the nervous system.

The 328-person individual-differences study is particularly important here.

Most of the variability could not be explained by the obvious psychological factors researchers measured.

Some people are simply much easier to trigger than others.

We still do not fully know why.

Does Contagious Yawning Decline With Age?

Some research suggests it can.

In the large individual-differences study, increasing age was associated with lower susceptibility.

Research on bonobos has also reported age-related patterns under certain conditions.

But age is not destiny.

Many older adults still catch yawns.

And because age explained only a small share of human variation, it cannot be used to predict confidently whether one individual will respond.

This is another recurring lesson in psychology.

Group averages describe tendencies.

They do not define individuals.

What Happens in the Brain Between Seeing and Yawning?

A simplified sequence might look like this:

Step 1: You Detect the Yawn

Visual or auditory systems recognize another individual’s behavior.

Step 2: Social-Perception Networks Respond

Brain regions sensitive to biological movement and socially relevant cues become active.

Step 3: The Action Is Represented Internally

Your nervous system processes what performing that behavior would involve.

Step 4: Motor Excitability Matters

Your motor cortex may become more or less prepared to generate the action.

Step 5: The Urge Reaches Awareness

You begin feeling:

“I need to yawn.”

Step 6: You Either Yawn or Suppress It

Conscious control can influence the final behavior.

It does not necessarily erase the urge.

This is simplified.

There is no single “yawn center” responsible for the whole process.

But it captures why contagious yawning can feel automatic while still being partially controllable.

Why Yawning Feels So Satisfying

A full yawn involves more than opening your mouth.

Muscles in the:

jaw;

face;

throat;

chest;

and respiratory system

participate in a coordinated action.

A yawn often includes a deep inhalation, jaw stretching and characteristic facial movement.

The combination can produce a sensation of release, particularly when someone is tired or has been sitting still.

This may also contribute to why suppressing a yawn feels uncomfortable.

The nervous system has initiated a coordinated motor program.

You are trying to interrupt it midway.

The sensation is similar to stopping a sneeze or preventing a stretch your body has already begun preparing.

Is Contagious Yawning Related to Other Contagious Behaviors?

Probably at a broad level.

Humans display many forms of behavioral and emotional contagion.

Laughter spreads.

Smiling spreads.

Crowds become tense together.

People unconsciously synchronize posture and speech.

Babies cry after hearing other babies cry.

Research comparing contagious yawning and contagious smiling has found overlaps as well as differences in their social correlates.

This does not mean every contagious behavior shares one mechanism.

But they all illustrate how strongly human nervous systems respond to other humans.

The News Ink’s article on why spicy food feels hot makes a different but useful point about perception: subjective experiences are created when sensory and neural systems interpret incoming signals. With contagious yawning, the triggering signal is social rather than chemical.

Does Being Close to Someone Make Their Yawn More Contagious?

Possibly, but not reliably enough to use as a relationship test.

Naturalistic human and primate studies have sometimes found stronger contagion among relatives or friends.

Other experiments have produced weaker effects.

Attention is a major confounder.

You may simply:

look more closely at someone you know;

notice their face more often;

sit closer to them;

or share similar states of fatigue.

Therefore, if your partner yawns and you do not, please do not conclude:

“Our emotional bond is disappearing.”

Science does not justify that interpretation.

Can You Use Yawning to Test Whether Someone Is a Psychopath?

No.

This is another internet myth built from small or indirect studies.

A person’s response to one yawn is not a clinical measure of:

empathy;

personality;

psychopathy;

autism;

or emotional connection.

Contagious yawning varies substantially among healthy people.

Most of that variation remains unexplained.

Clinical psychological assessment requires validated methods and professional interpretation.

Turning a common bodily behavior into a personality detector makes entertaining social-media content.

It is not good neuroscience.

Why Does Reading About Yawning Make This Article So Effective?

By now you may have yawned once.

Perhaps several times.

That illustrates one of the strangest features of the phenomenon.

The trigger can become increasingly abstract.

First:

a real person yawns.

Then:

a video of a person yawning.

Then:

the sound of a yawn.

Then:

a description of yawning.

The brain appears capable of activating the representation of the action from more than one kind of cue.

This helps explain why contagious yawning feels so difficult to avoid.

You cannot completely protect yourself simply by looking away.

The concept itself may be enough.

Frequently Asked Questions

Why do we yawn when someone else yawns?

Contagious yawning appears to involve social perception, attention and motor-system activation. Seeing or hearing another person’s yawn can increase your own urge to perform the same action.

Is contagious yawning caused by empathy?

Empathy has been proposed as one explanation, but the evidence is inconsistent. Some studies find relationships with social or empathic measures while others do not. Researchers do not currently consider yawning a simple test of empathy.

Can hearing someone yawn make you yawn?

Yes. Experimental studies have demonstrated auditory contagious yawning.

Can reading about yawning cause yawning?

It can. Scientific literature describes yawning being triggered not only by seeing and hearing yawns but sometimes by reading or thinking about them.

Why doesn’t everyone catch yawns?

People differ substantially in susceptibility. Age appears to explain a small part of the difference, but much individual variation remains unexplained.

At what age does contagious yawning begin?

Developmental studies suggest susceptibility becomes much more apparent around four years of age, although individual development varies.

Are yawns contagious in animals?

Evidence of yawn contagion has been reported in several social species, including some primates and dogs.

Does yawning mean the brain needs more oxygen?

The old explanation that yawning primarily occurs because the body needs extra oxygen is not well supported.

Can you stop a contagious yawn?

You can sometimes suppress or stifle the physical yawn. Research suggests resisting may actually increase the subjective urge to yawn.

Is contagious yawning a sign of intelligence?

There is no strong evidence that catching yawns provides a useful measure of intelligence.

Does yawning mean you are tired?

Yawning is strongly associated with sleepiness and transitions in arousal, but people can also yawn in other situations.

Is excessive yawning normal?

Occasional yawning is normal. A sudden or persistent major change in yawning accompanied by other symptoms should be discussed with an appropriate healthcare professional, because unusual yawning can occasionally occur alongside medication effects or medical conditions.

The Real Reason Yawns Spread From Person to Person

So why do we automatically yawn when somebody else yawns?

The most accurate answer is not:

because we need oxygen.

And it is not:

because empathetic people copy one another.

The science points toward something more interesting.

Human brains are built to monitor other humans.

We constantly read movements, expressions and signals.

Seeing another person perform an action can activate neural systems involved in understanding and preparing similar movements.

With yawning, that perception can create a genuine bodily urge.

Motor-cortex excitability appears to influence how strongly individuals respond.

Social attention matters.

Development matters.

Internal state probably matters.

And mechanisms related to behavioral or physiological synchronization may help explain why evolution preserved the phenomenon.

But important pieces remain unresolved.

We still do not know exactly why one person catches almost every yawn while another rarely does.

We do not know whether contagious yawning evolved primarily for group synchronization, communication, shared arousal or some combination of purposes.

And despite decades of research, empathy cannot yet provide the simple explanation that popular psychology often claims.

That uncertainty actually makes contagious yawning more fascinating.

A yawn feels trivial.

It lasts only a few seconds.

Yet it reveals how closely our bodies are connected to what we observe in other people.

Someone else opens their mouth.

Your brain recognizes the pattern.

Motor systems become more excitable.

An urge builds.

You try to resist.

And suddenly you are yawning too.

No conversation was required.

No conscious decision was made.

One nervous system observed another nervous system—and responded.

That may be the deepest lesson behind contagious yawning.

Humans do not experience the world as completely isolated individuals.

Our brains are continually adjusting to the people around us.

Sometimes the evidence is emotional.

Sometimes it appears in posture, laughter or facial expression.

And sometimes it is as simple as seeing one person yawn and discovering that your own mouth is already beginning to open.

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