You're listening to 20,000 Hertz.

I'm Dallas Taylor.

Our hearing is one of our core senses, and it's something most of us take for granted.

The laughter of a child, bird song at dawn, or even a well-designed sonic icon can be a feast for our ears.

But as much as it's a joy to listen to the world around us,

our hearing is also a protective mechanism.

It works hard alongside our other senses to add context and protect us from danger.

But a lot of people live without their hearing.

Worldwide, about one in every thousand babies are born deaf.

And right now, there are about a million people in the U.S. who live with complete hearing loss.

Brandon Edquist is one of those people. He's deaf now, but wasn't born that way.

Here he is through an interpreter.

When I was two, I contracted meningitis.

The illness infects the brain lining, and from that I lost my hearing.

There are lots of ways that a person can lose their hearing.

The biological machine for making sense out of sound waves is incredibly complex.

And like all machines, the more complex something is, the more there is to go wrong.

Issues can range from a simple buildup of earwax all the way to a punctured eardrum.

Hearing loss can also be caused by problems in the hearing organ or the nerve that carries sound signals

to the brain. They can be damaged by accidents and disease, but problems here can also be genetic

or a result of the natural aging process. Of course, not all hearing loss is immediate or total,

but when it is, people like Brandon tend to rely more heavily on their other senses.

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