"Hey man, it's not you, it's just my....: image via infoniac.com There is nothing more discouraging in human discourse than someone
yawning in your face while you're speaking to him. "Oh, excuse me," he
might say, "I guess I'm just very tired." (Yeah, sure!)
But now, scientists have evidence that your listener may not be bored at all;
but just chilling... his brain.
Andrew Gallup, a postdoctoral research associate at Princeton University's Department of Ecology and Evolutionary Biology and his colleague, Omar Eldakar, a postdoc fellow at the University of Arizona's Center for Insect Science studied yawning frequency among humans in relation to the temperature surrounding them.
Participants, 160 people randomly chosen, in the yawning experiments showed that people yawn more in the winter than in the summer, proving the labs' theory that yawning has a thermoregulatory function. This theory proposes that "yawning is triggered by increases in brain temperature, and that the physiological consequences of a yawn act to promote brain cooling." The cooling effect, the researchers report, is triggered by the opening and stretching of the jaw, as well as heat exchange with the ambient air that accompanies deep inhalation.
Participants in this study yawned almost twice as much when the temperature was significantly lower than their own body temperatures: image by Andrew Gallup
The studies took place outdoors in Tuscon, Arizona, where the ambient temperatures in summer average above 98.6 F, what is considered a normal body temperature. Winter temperatures average about 25 degrees less than our body temperatures at 71 F.
Because yawning is catching, the participants were shown images of people yawning to encourage them to yawn. Still, the results showed participants yawned significantly more in the cooler temperatures of winter than the summer.
There is more value in the yawning studies than just assuaging our ego or satisfying curiosity. Certain diseases and conditions, such as multiple sclerosis and epilepsy, have symptoms that include frequent yawning and thermoregulartory dysfunction. Gallup says that the results "provide additional support for the view that excessive yawning may
be used as a diagnostic tool for identifying instances of diminished
There, you're not boring. Your companion is chilling... his brain.
source: News at Princeton via RDMag