Why is yawning contagious?

Question

when ever someone yawns then i always yawn and that happens to everyone i know so i was just wondering why it is contagious

questions comments just I.M me

Answer 1

when you yawn, you chage the atmospheric pressure in the room - this creates an imbalance in the pressure of your body and so you yawn to rebalance this.  As each persons pressure changes, they each have to yawn to rebalance.

This isn't fact - just one of my theories.

Answer 2

duno, but did u see that episode of mythbusters where they tested it?(it was confirmed, :P)

Answer 3

When someone yawns, it affects a certain part of the brain called superior temporal sulcus. Hope that helps.

Answer 4

its coz you aren't getting enough carbon dioxide out of the body, stimulating the brain to make you yawn, therefore letting the carbon dioxide out of your body

Answer 5

it has something to do with potatoes..........im sure of it.

Answer 6

I have no idea i think it is because it makes you tired