I bet that over half of you will yawn after reading the title of this blog. Everybody knows about the phenomenon of “contagious yawning.” Contagious yawning is a well-documented action that occurs only in humans and chimpanzees.

There have been many studies of why we yawn, and why it is so contagious and although it is not entirely known, a new study from Duke University suggests that contagious yawning is not related to variables like empathy, tiredness, or energy levels. Researchers found that contagious yawning may decrease as people age.

The current study worked to better define how certain factors affect someone’s susceptibility to contagious yawning. 328 healthy volunteers, who completed “cognitive testing, a demographic survey, and a comprehensive questionnaire that included measure of empathy, energy levels, and sleepiness.” Participants then watched a three-minute video of people yawning, and the researchers recorded the number of times they yawned while watching the video. Out of the 328 people studied, 222 contagiously yawned at least once. When verified, the number of yawns was consistent. The only independent factor that significantly influenced contagious yawning was as age increase, participants were less likely to yawn.

Another idea about contagious yawning is based on the “hyperthermia hypothesis.” This hypothesis suggest that yawning helps cool down our brains. Researchers in 2007 found that holding warm or cold packs on the forehead affected how often people yawning while watching videos of other people yawning. Cold packs decreased yawning while warm packs increased yawning. Research has also revealed that mice show increased brain temperatures before yawning and that people are more likely to yawn when the air is cool.

Since this question is unanswered, for now we will just continue on with the phenomenon of contagious yawning. Also, you’ll yawn after looking at the picture below!