• United States
6 Dec 06
I definitely agree that yawning is very contagious. It seems like everytime that someone around me yawns, I yawn too or vice versa. Don't know why it is that way but it does seem contagious and goes around quickly. I find it funny more than annoying. :-)
6 Dec 06
A Yawn is a reflex of deep inhalation and exhalation associated with being tired, with a need to sleep, or from lack of stimulation. It is also claimed to help increase the state of alertness of a person. The exact causes of yawning are still unknown. It is also theorized that yawning helps redistribute an oil-like substance which coats the lungs and aids breathing. Some have observed that if you try to stifle or prevent a yawn by clenching your jaws shut, the yawn is unsatisfying. As such, the stretching of jaw and face muscles seems to be necessary for a good yawn.