Why is yawning contagious? - P.H. If you don’t think YAWNING is contagious, see if you YAWN by the time you’re done reading this explanation of YAWNING. First, let’s dispel a myth. You don’t yawn to take in extra oxygen. “That’s been rejected in lab tests,” says YAWN expert Robert Provine, professor of psychology at the University of Maryland’s Baltimore County campus. He had test subjects breathe air with extra oxygen. For others, he reduced the oxygen intake by giving them air high in carbon dioxide. Neither caused more or less YAWNING. (YAWN. YAWN. YAWN.) Provine says “we YAWN when we’re changing states of activity. Going from sleep to wakefulness, like YAWNING in the morning. Or wakefulness to sleep.” (He says we YAWN more in the morning when we wake up, by the way.) “Concert pianists will YAWN before going out to an important performance. Olympic athletes YAWN before the big event. Embryos begin YAWNING eleven weeks after conception,” Provine notes. He says YAWNING is somehow connected to changing levels of body activity, changes from one state to another, like inactive to active or vice versa, but nobody understands just what the connection is. “It probably helps stir up the blood and brain chemistry to facilitate those transitions from one level of activity to another.” Why? “YAWNING is ancient and autonomic,” Provine says. “Maybe it’s to get everyone in the tribe to synchronize their states of activity, to increase the success of the tribe if everyone’s working together. We really don’t know.” (YAWN. YAWN. YAWN.) YAWNING is highly contagious, he says. Every vertebrate species YAWNS. Fish YAWN. Birds YAWN. Alligators YAWN. But Provine says it’s apparently only contagious in humans. Provine has made test subjects YAWN by showing them a YAWNING face. Interestingly, if he shows them just the YAWNING mouth, it doesn’t trigger the YAWNING. If he covers the mouth, and shows them just the nose and eyes of the YAWNING face, it does. He’s made subjects YAWN by talking about YAWNING, or asking the test subjects to think about YAWNING, or by having them read about YAWNING. Yawning yet? David Ropeik is a longtime science journalist and currently serves at Director of Risk Communication at the Harvard Center for Risk Analysis. This article is adapted from the archives of “How and Why,” Ropeik’s column about scientific puzzlers, and was first published in March 2000.
yeah that was dumb, i just woke up, i even pictured a guy yawning, i have no desire to yawn yet...but what they wrote is true, my teacher (a proffessor, so he claims) said you yawn when your body is about to shut down, it somehow gives you more energy...
