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Michael: You know that feeling when you’re flying on an airplane, and your ears feel kind of stuffy? So you yawn really wide, and then there’s a POP, and that pressure is gone. But sometimes you can also hear a little popping in your ears when you just swallow normally. It’s the exact same ear anatomy at work, just keeping your ears healthy.

To understand what’s happening, you have to understand how our ears process sounds. There are three sections that work together: the outer, middle, and inner ear. The outer ear is the part we can see and decorate with piercings. It funnels sound waves toward the eardrum, which is basically a thin membrane.

The eardrum then vibrates three tiny bones in the middle ear, which is a small chamber that’s mostly filled with air. It’s connected to the back of your throat by a eustachian tube, which is what make your ears do the popping thing. These tubes are normally sealed shut, to keep your middle ears safe from all the junk in the back of your nose and throat. But when you swallow or yawn, these tubes briefly open, to help drain out any fluid and bring fresh air into the middle ear.

Finally, there’s the inner ear, which is a spiral-shaped cavity filled with fluid that changes the bone vibrations into sound signals that are sent to the brain. Normally, the air pressure is the same in both the outer ear and the middle ear, meaning there’s about the same amount of air molecules bouncing around in each chamber, sealed off from each other by the eardrum.

But when you’re flying in an airplane, for example, the atmosphere around you has fewer molecules. So the air pressure around you, and in your outer ear, is lower. But the air pressure in your middle ear stays the same.

The extra air molecules in your middle ear push a little more on your eardrum, so the membrane bulges out a little bit, and causes that uncomfortable stuffy feeling. Your eardrum also can’t transmit sounds as well, because it’s stretched too much to vibrate normally. So when you chew gum, or swallow really hard, or yawn, you’re trying to open up your eustachian tubes, so the air in the middle ear can have the same pressure as the airplane cabin.

The rush of air into or out of your middle ear, and your eardrum adjusting a little bit, is the “pop” you hear. Doctors recommend being careful about holding your nose and blowing though. Because if you blow too much air through your eustachian tubes you could tear your eardrum, or just send gross stuff from the back of your throat into your middle ear.

But a really gentle blow or swallow to pop your ears on an airplane is totally normal, and healthy. And it has nothing to do with popping your actual eardrum. Because... that would hurt.

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