From DeFacto Sound, you're listening to 20,000 Hertz.

The stories behind the world's most recognizable and interesting sounds.

I'm Dallas Taylor.

This is the story behind our hearing and what happens when it goes away. Even a small amount of hearing loss can significantly impact a person.

Almost 40 million American adults, that's 15% have difficulty hearing.

And it gets worse, the older you get.

And right now, the world is louder than it's ever been before.

Hearing loss, for the most part, tends to be a gradual thing for people as they age.

That's audiologist Lindsay Prusick.

When people have hearing loss, largely it's an invisible thing.

You don't see it, but it has such a profound impact on people's ability to connect,

communicate, even ultimately their quality of life.

There are a lot of people who are born with hearing loss.

It can be as a result of genetics, syndromes,

things acquired through when a mother gives birth to a baby,

various viruses, that type of thing.

Because it's so invisible, many people don't think about hearing loss very much at all.

Really, in general, for the majority of people with hearing loss, it's a very gradual thing.

People start to notice over time, oh gosh, it's hard to understand speech. Things sound muffled.

People sound like they're mumbling.

Or just the quality of sound begins to decrease.

This is a good thing to remember when you're talking to older people.

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