The Edmond Sun

August 12, 2013

HEY HINK: Science of yawning proves doggone interesting

Mike Hinkle
Special to The Sun

EDMOND — Picture this; it’s a snowy day. You’re sitting by a cozy fireplace in the perfect easy chair. You’re sipping a warm cup of cocoa listening to deeply relaxing music through high-quality headphones. You feel a refreshing stretch coming on. You set down the cocoa and allow yourself to slip into the luxury of a great, eye watering ... yawn. Do you feel a relaxation in your jaws? Not surprising. Yawning is one of the most potent social contagions known to man. You can see, hear, read about or even think about — yawning — and you’re apt to feel the temptation to enjoy a big one yourself.

Yawning is on my mind this week as this odd physiological phenomenon appears in a recent scientific headline. By way of background, the word itself — yawn (there it is again, that urge) — is a word of great antiquity. Its origins are lost in the mists of prehistory.

The contagious nature of yawning has been noted for centuries. A venerable French proverb holds “One good gaper (yawner) makes seven others gape.”

According to some scholars, yawning was once associated with the risk of allowing evil spirits to enter and possess the unwary. In his book “De Rerum Inventoribus,” Vergil remarks on the custom of making the sign of the cross while yawning because, “deadly plague was sometime in yawning, therefore, men used to fence themselves with the sign of the cross … which custom we retain to this day.”

Even after yawning lost its association with plague and demon possession, this contagious behavior inspired a host of social “do’s and don’ts.” For example, 17th century British scholar Frances Hawkins, in his book “Youth’s Behavior, or Decency in Conversation amongst Men” offers this instructive guideline: “In yawning, howl not, and thou shouldest abstain as much as thou can to yawn, especially when thou speakest.” (Pay particular attention to the “howling” part as it might be important later.)

No less a personage than George Washington weighs in on the etiquette of the yawn: “If you cough, sneeze, sigh or yawn, do it not loud, but privately and speak not in your yawning, but put your handkerchief or hand before your face and turn aside.”

An overly luxurious yawn in a Los Angeles courtroom in 2005 exposed a transgressing juror to contempt of court charges. Yawning when anyone is speaking or performing is regarded as a demonstration of boredom, whether it’s true or not. In fact, Mason Cooley, a noted American aphoristic suggests “A yawn is more disconcerting than a contradiction.”

Yawning and its contagious nature is not limited to humans. It has been observed in snakes, fighting fish, penguins, owls, dogs, cats, horses, seals, baboons and guinea pigs. Last week, dog yawning in particular is in the science news.

According to the Aug. 7 edition of Science Daily News, Teresa Romero and her colleagues at the University of Tokyo discovered something remarkable. Researchers have known for some time that a dog yawn can trigger yawns in other dogs. Moreover, human yawning also can spread to nearby canines. In recent experiments, pet dogs were exposed to three types of human behavior; the bona fide yawns of their owners, bona fide yawns of strangers and fake yawns of strangers. Romero and her colleagues discovered that bona fide yawns from the dog’s owner is more likely to produce a bona fide yawn in a pet dog. On the surface this suggests, of course, that dogs are not likely to be fooled by fake yawns and they’re not as likely to be impressed by the yawns of a stranger. There’s something about the emotional bond between a dog and its owner that expresses itself in community yawning.

The explanation for yawning has never been scientifically settled. One theory suggested that yawning is some type of stress response. However, in the Tokyo University experiments, the researchers not only observed the dogs’ yawning faces, but also monitored heart rates. The dogs demonstrated no significant cardiac changes during the experiments which undercut the notion that yawning is stress-related. In Romero’s words, “Our study suggests that contagious yawning in dogs is emotionally connected in a way similar to humans. Although our study cannot determine the exact underlying mechanism operative in dogs, the subjects’ physiological measures taken during the study allowed to counter the alternative hypothesis of yawning as a distress response.”

Once again, science verifies a fact that dog lovers have been saying for years. The emotional bond between dogs and their owners is deep beyond measuring. In addition to everything else they share, we now know there’s also that deep, satisfying yawn. I’m Hink and I’ll see ya.

MIKE HINKLE is a retired attorney and Edmond resident.