Joseph Francis Max Perrella And Kirk
McKeever Mulligan

1. Title
2. Contents
3. Background: What is Yawning?
4. Background: Why do we Yawn
5. Background: Animal Yawning
6. Why is Yawning Contagious
7. Why is Yawning Contagious Cont.
8. Why is Yawning Contagious Cont.
9. Why is Yawning Contagious Conclusion

• Yawning is an inhalation of air, with a simultaneous stretching of the eardrums
– Yawning is followed by an exhalation
• Pandiculation: stretching an yawning at the same time

• Multiple theories
– Yawning occurs when an animals blood contains an increased amount of carbon dioxide
• The body is forced to yawn to increase the influx of oxygen
– Yawns are a way to open up one’s muscles, accompanied by the urge to stretch it allows animals to exert to their full physical potential
– Yawning may be the body’s way of regulating brain temperature

• Animals Yawning can serve as a warning signal
– Charles Darwin discovered baboons yawn to threaten their enemies
• Snakes yawn to realign their jaws after eating and for respiration reasons
• Dogs often yawn after seeing humans yawn, and when they feel uncertain
• Fish also yawn when they need more oxygen

• Contagious yawning has been observed since the 16 th century
– A translated French proverb from 1508 says “one man’s yawning makes another yawn.”
• Observing another persons yawning face (especially eyes), reading, thinking, or even looking at a yawning picture can cause someone to yawn

• The most probable case for contagious yawning lies within our brains
– Mirror neurons in our frontal cortex are stimulated by seeing others from the same species perform gestures.
– Yawning is thought as an imitative impulse
• Young autistic children do not increase their yawning after seeing others yawning, because their frontal cortex is less developed to imitate
(same reason why they are less socially “normal”)

• Empathy is thought to also be a strong cause of yawn contagion
– Yawns are most contagious when we see our family, then friends, then acquaintances, and lastly strangers yawn

• Conclusion: Yawn contagion is because of the imitation neurons in our brain, and its magnitude is driven by the emotional closeness between individuals