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The Science Behind Why Yawning Is ‘Contagious’
You’ve been yawning since before you were born. Photo Credit: Shutterstock

31. Babies Yawn Before They Are Born

Few things have the “aww” factor quite as much as watching a newborn baby yawn. However, that first yawn that the parents see is not the child’s first; babies begin yawning in-utero. In 4-D resonance scans of fetuses, scientists previously believed that the babies were opening their mouths.

Nevertheless, in a study released back in 2012, scientists discovered that the babies were yawning. In fact, fetus yawns are twice as common as when they open their mouths. The yawns decrease in frequency after 28 weeks of gestation, which is about seven months into pregnancy.

The Science Behind Why Yawning Is ‘Contagious’
What is your yawn trying to tell you? Photo Credit: iStock

32. Yawning Indicates Fatigue

Behavior scientists are particularly interested in yawning as a social contagion, but that is far from the only reason why we yawn. You are far more likely to yawn when you are tired, whether you are by yourself or surrounded by other people.

When you yawn, your body energizes itself by consuming copious amounts of oxygen and releasing the toxic by-product of respiration, carbon dioxide. Beyond that, scientists aren’t entirely sure why fatigue leads to excessive yawning. Maybe you are just less likely to be able to resist the impulse when it strikes, but there are likely many explanations.

The Science Behind Why Yawning Is ‘Contagious’
Make sure you are getting enough sleep. Photo Credit: Shutterstock

33. Lack of Sleep Can Cause Excessive Yawning

Lack of sleep isn’t the same as fatigue. Fatigue is an acute feeling of drowsiness that isn’t always associated with sleep deprivation; you may be fatigued simply because you engaged in a heavy exercise session. Lack of sleep, or sleep deprivation, is going without proper sleep for an extended amount of time.

You may have sleep deprivation because of a sleep disorder, like sleep apnea. If you are yawning excessively, your body is probably trying to tell you that it is not firing on all cylinders. If that is the case, you may need to see your doctor and possibly a sleep specialist.

The Science Behind Why Yawning Is ‘Contagious’
If you yawn excessively, you need to see a doctor. Photo Credit: Shutterstock

34. Excessive Yawning May Be A Warning Of A Heart Attack

The vagus nerve is a critical cranial nerve that helps control the function of muscles and organs throughout the body. Internal bleeding, especially in your chest, can trigger your vagus nerve to cause you to yawn excessively.

In rare circumstances, you may yawn because the vagus nerve is attempting to tell your brain that a heart attack is imminent. If you are yawning excessively and are not fatigued or sleep-deprived, you should see a doctor to find out if something is going on. You should also make sure that you are familiar with the symptoms of heart attacks.

The Science Behind Why Yawning Is ‘Contagious’
There are lots of reasons why we yawn. Photo Credit: Shutterstock

35. Yawning May Be A Response To Medication

There is no shortage of physiological and behavioral explanations as to why we yawn. To add another to the repository, consider that certain medications, especially selective serotonin reuptake inhibitors (SSRIs), can also cause yawning. SSRIs increase the level of serotonin in the brain.

If you are on antidepressants, antihistamines, or some other medications, you may be more likely to yawn because of the SSRIs you are consuming. If you are on antidepressants, the extra yawning increases the effect of the medications, as the excess serotonin in your brain created by the yawning reflex helps to improve your mood.

The Science Behind Why Yawning Is ‘Contagious’
Yawns are contagious. Photo Credit: Shutterstock

36. Excessive Yawning Can Also Indicate Epilepsy

Epilepsy is a condition that results from brain damage and causes seizures. The injury causes the brain to send out erroneous signals, which can include excessive yawning. While excessive yawning doesn’t automatically mean that you have epilepsy or another disorder, it does mean that you need to go to the doctor and get evaluated.

In addition to yawning, another neurological symptom that excessive yawning can indicate is a brain tumor or an impending stroke, particularly a stroke or tumor that is associated with the brain stem. Possibly the pressure on the brain stem stimulates a yawning response.