Seeing or hearing someone yawn can make you yawn. This phenomenon is not limited to humans; some animals experience contagious yawning, too. But why is yawning contagious? Brain cells called mirror ...

Contagious yawning refers to the tendency of individuals to yawn after seeing, hearing, or even thinking about someone else yawning. About 40% to 60% of people exhibit contagious yawning when exposed ...