Even reading about yawning makes me yawn. Why is this?
138081
Professor Andrews told Scientific American yawns may be contagious because we human animals are trying to communicate changing environmental conditions to others, possibly as a way to synchronize behavior. Obviously, this would be one of those caveman-type mechanisms that is no longer needed that our bodies remember and still do.\n\nWhen we yawn, we draw in more oxygen and remove a build-up of carbon dioxide. Larger groups produce more carbon dioxide. So one theory holds that we yawn when we're in large groups of people to purge the carbon dioxide--and in so doing, we set off a chain reaction. But Robert Provine, a psychologist at the University of Maryland, Baltimore County, tested the theory and says it's bunk. Giving people additional oxygen didn't decrease yawning and decreasing the amount of carbon dioxide in a subject's environment also didn't prevent yawning, notes the How Stuff Works Web site.\n\nWhatever the reason for yawns being contagious, How Stuff Works reports that 55 percent of people will yawn within five minutes of seeing someone else yawn. In addition, blind people will yawn after hearing others yawning. And we're sure that reading and writing about yawns is enough to induce one!
548404
From Wikipedia:\n\n"A previous long-standing hypothesis is that yawning is caused by an excess of carbon dioxide and lack of oxygen in the blood. The brain stem detects this and triggers the yawn reflex. The mouth stretches wide and the lungs inhale deeply, bringing oxygen into the lungs and hence to the bloodstream. It is almost certain, however, that this hypothesis is not correct. One study has documented that this effect does not exist."\n\nGoes on to newer, updated theories.\n\nAlso:\n\n"The reasons for this are unclear; however, recent research suggests that yawning might be a herd instinct. Other theories suggest that the yawn serves to synchronize mood behavior among gregarious animals, similar to the howling of the wolf pack during a full moon."\n\nGoes on to give other reasons for contagion. <Yawn!> Enough!
148403
Yawn while opening your mouth wide open. Wide as possible.
184728
oh my god theres an invasion of yawning questions
235430
Dr. Barry Make, a pulmonologist at National Jewish Medical and Research Center in Denver, says the answer is not because we are tired or bored — although that’s the common perception. Read on for his explanation.\n\nThe most plausible explanation, and the one that is taught in medical school, is that we yawn because oxygen levels in our lungs are low.\n\nTHE TRUTH IS that we don’t completely understand why people, or animals for that matter, yawn. It’s widely assumed that yawning occurs because we are tired or bored or because we see someone else doing it, but there isn’t any hard evidence to support these beliefs.\n\nThe most plausible explanation, and the one that is taught in medical school, is that we yawn because oxygen levels in our lungs are low. Studies have shown that during normal, at-rest breathing, we don’t use anywhere near our lung capacity; for the most part, we just use the air sacs at the bottom of the lungs. If the air sacs, called alveoli, don’t get fresh air, they partially collapse and the lungs stiffen a bit. As a result, it’s believed, our brain prompts the body to either sigh or take a yawn to get more air into the lungs.\n\nBut certain aspects of yawning remain even more mysterious. Fetuses, for instances, have been observed yawning in the womb, yet it’s known that they don’t take oxygen in through their lungs. And yawning seems to be a symptom of multiple sclerosis and other medical conditions, for reasons unclear.\n\nAnother puzzling phenomenon is that some male animals, men included, yawn in association with penile erection (although it’s presumptuous to assume they’re bored with their sex lives).\n\nNext time you're in a meeting, try this little experiment: Take a big yawn, cover your mouth out of courtesy, and watch and see how many people yawn. There's a good chance that you'll set off a chain reaction of yawns. Before you finish reading this question of the day, it's likely that you will yawn at least once. Don't misunderstand, we aren't intending to bore you, but just reading about yawning will make you yawn, just as seeing or hearing someone else yawn makes us yawn. \n\nInteresting Yawning Facts\n•The average yawn lasts about six seconds. \n•Your heart rate can rise as much as 30 percent during a yawn. \n•55 percent of people will yawn within five minutes of seeing someone else yawn. \n•Blind people yawn more after hearing an audio tape of people yawning. \n•Reading about yawning will make you yawn. \n•Olympic athletes often yawn before competition. \n\nWhat's behind this mysterious epidemic of yawning? First, let's look at what a yawn is. Yawning is an involuntary action that causes us to open our mouths wide and breathe in deeply. We know it's involuntary because we do it even before we are born. Research shows that 11-week-old fetuses yawn. \n\nThere are many parts of the body that are in action when you yawn. First, your mouth opens and jaw drops, allowing as much air to be taken in as possible. When you inhale, the air taken in is filling your lungs. Your abdominal muscles flex and your diaphragm is pushed down. The air you breath in expands the lungs to capacity and then some of the air is blown back out. \n\nWhile the dictionary tells us that yawning is caused by being fatigued, drowsy or bored, scientists are discovering that there is more to yawning than what most people think. Not much is known about why we yawn or if it serves any useful function and very little research has been done on the subject. However, there are several theories about why we yawn. \n\nHere are the three most common theories: \n•The Physiological Theory -- Our bodies induce yawning to drawn in more oxygen or remove a build-up of carbon dioxide. This theory helps explain why we yawn in groups. Larger groups produce more carbon dioxide, which means our bodies would act to draw in more oxygen and get rid of the excess carbon dioxide. Howeve
132082
There are two possible reasons for tears to be released when you yawn. \nThe tears are secreted by the "lacrimal glands" located just inside the eye \nlids next to the nose. These glands secrete the fluid into the "lacrimal bag" \nwhere it is then released through the "lacrimal ducts" into the lining of the \neye lids to keep the eye moist.\n\nWhen you yawn it is possible that there is pressure put on the "lacrimal \nbag" and some fluid is forced out. \n\nThe secretion of the "lacrimal glands" is under control of the autonomic \nnervous system. This nervous system controls all the involuntary functions \nas contrasted to the somatic nervous system that controls all purposeful \nactions. When you reach out to catch a ball it is the somatic system that \nactivates the muscles to acheive that action. The autonomic system \ncontrols such things as the heart beat, sweating and the function of the \nintestines.\n\nWhen the autonomic portion of the nerves are activated the "lacrimal \ngland" secretes the tears which appear at the eye. These nerves also \ncause the pupil of the eye to constrict and get small as well as to cause\nthe glands in the nose to secrete. So, when you are crying you get tears,\na watery nose and your pupils should constrict. Perhaps the act of \nyawning causes activation of these nerves. Next time you yawn look in \nthe mirror and see it your pupils get small. But don't get too close to the \nmirror because when you look at things close to you the pupils get smaller \nanyway.
21134
Well, I don't know why yawns are contagious because scientists really don't know what cause yawn's in the first place. However, on a lesser level, I believe yawns are contagious because when you see someone yawn, you tend to think of how tired you are. Therefore, you yawn too. And plus it is pretty amusing when you have a yawn fest with someone and just cannot stop yawning back and forth.\nHope this helps!\n\nP.S. I yawned while writing this...twice actually ;)
71398
during, before, after... heck I am just tired
610082
That always happens to me, but it has to do with my asthma.  Asthmatics sometimes don't get enough oxygen as a normal person would with ordinary breaths, and thus have to take deeper breaths (probably without realizing it) to get the job done.  I often find myself doing that... and yawning can have to do with that as well.  Sometimes when exerting a lot of energy, my asthma kicks in just a little bit, and I start yawning.\nAnxiety could also cause this.\n\nAlso it could just be that your other breaths, that aren't so deep, aren't bringing in enough oxygen-- so you have to rectify that by breathing more heavily every so often.\n\nIf you find it happening in certain locations, such as only at work-- it could be that the ventilation isn't that great, and fresh air isn't coming in as much as it should.\n\nAlso, being around a lot of smoke certainly won't make your lungs work any better.\n\nAll in all, there are a lot of explanations... I would just mention it to your doctor next time you go.  If it gets any worse, you should make an appt to see him.
410919
A yawn is in response to too much CO2 in the blood stream.  When you yawn there is a negative feed back loop in operation which tells the diaphram to contract (take a breath) because there is too much CO2......the yawn actually increases CO2.\nThe sneeze is due to irritation in the beginning of the respiratory tract, it expells such things as dust, bacteria and other irritants from your nose and sinuses.\nA hiccup is a sligh malfunction or mistiming if you will of the glottis which is a membrane that closes in your throat to prevent food from going into your lungs when you swallow.  Whenyou ge tthe hiccups it starts to close while you are taking a breath or expelling a breath.  It just takes a bit of time for your body to reset when it closes
244477
Try reading in a none traditional place. Go outside in the sun. Make sure you are well rested before. How is your blood work? Have you had a physical lately? One may have nothing to do with the other. You may be anemic or you may be eating heavy meals before you read. Carbs make you feel full and tired. It may be dietary. Who knows?
560021
Take a multi vitamin I have the same problem but when I remember to take my vitamins in the AM I don't yawn or feel as tired after eating. You  can also  try taking a short walk after you eat to get the digestion working a lil faster.
143378
It is a "associative" reaction. You see someone yawn and it triggers the same reaction because in our experience yawning represents being tired. We therefore associate yawning by others or ourself with being tired.\n\nI get a similar associative reaction when my daughters and I say the Lord's Prayer every night at bedtime. Halfway thru the prayer they will both yawn like clockwork. They both associate the prayer with being sleepy. Puts them right to sleep every time!
423891
If what Bean and KD Baby said were true that our bodies make us yawn to drawn in needed oxygen, wouldn't we yawn during exercise?\nIn the dictionary, yawning is said to be caused by boredom, fatigue or drowsiness. Although we do tend to yawn when bored or tired, this theory doesn't explain why Olympic athletes yawn right before they compete in their event. It's doubtful that they are bored with the world watching them.  The simple truth is that even though humans have been yawning for possibly as long as they have existed, we have no clue as to why we do it, so maybe yawning is triggered by some area of the brain we have yet to discover. We do know that yawning is not limited to man. Cats, dogs, even fish yawn, which leads us back to the idea that yawning is some form of communication.
14777
i think i might know what you are talking about, i think the reason y u have weird noises is because u might just be burping. when u breathe in deeply u swalow some air that needs to be released. when u yawn do u have those noises too?
2880
when you yawn it means you're either tired or your brain needs more oxygen
114584
yawn and strech, feed my cats, make coffee...in that order :-D