Lecture Notes: The Science of Yawning

Introduction

• Speaker: Michael from Vsauce
• Topic: Yawning and its contagious nature

What is Yawning?

• Definition: Inhaling air and stretching eardrums
  • Ears pop when you yawn
• Pandiculation: Yawning while stretching the whole body

Common Misconceptions

• Misbelief: Yawning occurs due to the need for more oxygen
• Studies: Oxygen levels do not influence yawning frequency
• Exercise: Doesn't increase yawning despite higher oxygen need

Cooling Theory

• Brain Temperature: Yawning helps cool the brain
  • Brain functions best at specific temperatures
  • Outside air cools facial blood
• Parakeets Study: Yawn within a specific temperature range
  • Observations: No contagious yawning in parakeets

Contagious Yawning

• Experiment: Ice packs reduce contagious yawning
  • University of Albany: Ice packs keep brain cooler
• Benefits of Yawning:
  • Increases blood pressure
  • Stretches facial muscles
  • Enhances focus
  • Pandiculation readies muscles for use

Evolutionary Advantage

• Prey Animals: Contagious yawning keeps herd alert
• Empathy Connection: Related to empathy, not disease-like contagion
• Emotional Contagion: Emotions influence others’ feelings

Yawning and Empathy

• Autistic Children: Yawn less when watching yawning videos
• Studies:
  • University of Pisa: Yawn contagion stronger with family
  • Leeds University: Empathy test linked to yawning frequency

Animal Yawning

• Different Species: Various reasons for yawning
  • Guinea Pigs & Monkeys: Intimidation, showing teeth
  • Penguins: Attract mates
  • Snakes: Align jaws, open tracheas after eating
  • Fish: More yawning when oxygen is low or water temperature is high

Conclusion

• Human Yawning: Likely serves unique purposes for humans
• Ancient Signal: Yawning signals readiness and survival

Closing

• Quote: "Let's do this, let's survive."
• Thanks for Watching