Post on 22-Mar-2016
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transcript
Why Is Yawning Contagious
Joseph Francis Max Perrella And Kirk McKeever Mulligan
Contents
1. Title 2. Contents3. Background: What is Yawning?4. Background: Why do we Yawn5. Background: Animal Yawning6. Why is Yawning Contagious7. Why is Yawning Contagious Cont.8. Why is Yawning Contagious Cont.9. Why is Yawning Contagious Conclusion
What is Yawning• 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
Why do we Yawn
• 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• 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
Why is Yawning Contagious
• Contagious yawning has been observed since the 16th 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
Why is Yawning Contagious Cont.
• 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”)
Why is Yawning Contagious Cont.
• 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
Why is Yawning Contagious Conclusion• Conclusion: Yawn contagion is because of the
imitation neurons in our brain, and its magnitude is driven by the emotional closeness between individuals