how are yawns so contagious?
78675
Contagious yawning is triggered involuntarily when we observe another person yawn -- it is a common form of echophenomena -- the automatic imitation of another's words (echolalia) or actions (echopraxia). And it's not just humans who have a propensity for contagious yawning -- chimpanzees and dogs do it too.
1080622
Summary: Contrary to common belief that the yawning contagion is associated with empathy, it is in fact, more likely that perceptual sensitivity is to blame, research suggests. ... Researchers found that those who were more likely to detect yawning from a face were also more likely to be induced to yawn.
1460747
A classic symptom of fatigue, yawning can sometimes be a sign that your body is ready for sleep. It's a common occurrence: Animals yawn, babies yawn, and adults yawn. But a yawn is not necessarily a sign that you are tired—check out these other potential causes.
177299
Scientists have shown for the first time that unborn babies yawn repeatedly in the womb. But they do not believe it is because they are sleepy or bored. The most likely explanation is that foetal yawning is an essential process linked to brain development.
201021
Call it the finding that puts the "aw" in yawn—scientists have discovered that people yawn more in response to the yawns of people they care about most. So-called contagious yawning is a type of psychological effect that happens only in response to seeing, hearing, or reading about yawning.
959320
A new study, however, has revealed that babies and young children are immune to "catching" yawns until they reach the age of five years old. The surprising findings have shed new light on this mysterious phenomenon, which scientists describe as contagious yawning.
621923
The snapshot sequence starts with Don-chan, the bigger of the two, letting out a jumbo-sized yawn. Mogu-chan carefully observes the gesture… …and then, just like happens with humans, shows that the yawn is contagious! “Cats catch yawns from each other too,” tweeted @nanao_ssan with the photos.
1144736
A. People yawn when they're tired, but also when they wake from a night's sleep. We yawn when we're bored, but also when we're anxious, or hungry, or about to start a new activity. ... Reading about yawning makes people yawn.
749993
The average adult yawns 20 times per day. And when you feel a yawn coming on, it can be nearly impossible to suppress.
1205794
"Young children may also do less contagious yawning simply because they don't have the same pressures or social inhibitions as adults. They yawn where they like and when they like," he said. Recent research also overturns the notion that we yawn because we're bored.
1139356
Mumps is highly contagious and spreads rapidly among people living in close quarters. The virus is transmitted by respiratory droplets or direct contact with an infected person. Only humans get and spread the disease.
76888
Although excessive yawning is usually attributed to being sleepy or bored, it may be a symptom of an underlying medical problem. Certain conditions can cause a vasovagal reaction, which results in excessive yawning. During a vasovagal reaction, there's increased activity in the vagus nerve.
376919
I've been doing some 'observation' and reckon that big yawns may simply cause the eyes and the tear ducts to get scrunched up so that the extra pressure squeezes out the tears - and this then makes the nose run too. (Blinking rapidly also produces tears).
736986
Yawning is usually harmless, but it is possible to yawn too much. Excessive yawning can be caused by a few different disorders that require medical attention. The vagus nerve, which is the nerve connecting the throat and abdomen to the brain, can cause excessive yawning by interacting with the blood vessels.
208061
Here's the basic idea: When you start to yawn, powerful stretching of the jaw increases blood flow in the neck, face, and head. The deep intake of breath during a yawn forces downward flow of spinal fluid and blood from the brain. Cool air breathed into the mouth cools these fluids.
800120
Sneezing, fever, and a hacking cough are all signs that you could be contagious. Even if you feel all right, your symptoms — or lack thereof — could be deceiving. Even with mild illnesses, you can spread germs, too. Here's how to tell whether you're contagious and if you need to stay home.
1021627
Styes are usually the result of Staphylococcus bacteria. They are not contagious, as people cannot transmit them to one another. However, if the bacteria is on a pillowcase or towel and comes into direct contact with an eye, the person is at risk for developing a stye.