Fun fact: humans and chimps (or other types of primates) are the only animals known to yawn!
There are two types of yawning: spontaneous yawning which occurs when on his tired or bored, or contagious yawning when someone yawns after witnessing another individual yawn. Spontaneous yawning is someone one is born doing, while contagious is adapted in early childhood.
A study done at Duke University tested 328 participants. The volunteers had to answer questions concerning their previous energy and empathy levels. The participants were to record the amount of times they yawned while watching a three minute movie of other people yawning. Out of the 328 participants, 222 of the volunteers admitted to yawning at least once throughout the video. However, the amount of yawns per person ranged from 0 – 15 times. I watched the video myself ( here it is if you want to test out the experiment) and I yawned twice, but it is also important to note that it is late in the library and I am on very little sleep.
The null hypothesis was that watching someone yawn does not cause the watcher to also yawn. The only slight variable the study was able to find was age, the older the person the less likely they were to yawn. However, that only accounted for a very small percentage of the participants and therefore not a definite cause.
Another interesting aspect to note is that schizophrenics and autistic individuals do not experience contagious yawning. When studying the brain during contagious yawns, mirror neurons light up in fMRI scans. There are new studies being done to see if mentally ill patients lack or have deficient MNS, which could lead to new research on how to help individuals with these diseases.
Yawning also relates to empathy levels, also known as your ability to feel for others. So if you’re not a contagious yawner, well then you might just be an asshole. A study done in Leeds England tested 80 students, half psych majors and the other half engineering. The students were to sit alone with and undercover assistant who yawned 10 times. They were then given a test to record their emotions. The participants were shown 40 different images of eyes and were asked to describe the emotions the eyes showed.
The results of the study were very interesting. The psych majors, who’s futures are most likely going to deal with others feelings, yawned 5.5 times on average while the watching the 10 yawns in comparison to the engineering majors only yawning 1.5 times. In terms of the eyes, the psych majors were able to correctly analyze 28 out of the 40 eye emotions while the engineering majors only got 25 out of the 40. Surprisingly, results did not vary between gender. Brain imaging also highlights that contagious yawns and empathy occurs in the same areas of the brain.
So maybe contagious yawning really is scientific after all. However, much more research still has to be done before there can be and confident claims on the cause. BTW while writing this post, I yawned at least 6 times.