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Even in a room filled with voices, we can usually pick out the speech coming from one person.

Sugar is very sweet. I mean how else would you survive the holiday season, right?

But after a concussion, those same words can be a lot harder to pick out.

And to talk about that experience, I have NeuroNerd, John Hamilton here with me. Hey, John.

Hey, Emily.

So you cover neuroscience friend PR. When it comes to concussions, I thought I knew most of the symptoms, like headaches, dizziness, memory problems, confusion.

Now you're telling me it also affects your hearing.

Well, yeah, I mean, sort of.

Okay.

What's different is that often these hearing problems we're talking about are in people whose ears work just fine.

If you gave them a typical hearing test, they would pass.

Uh-huh.

But if you tested their ability to pick out those words, sugar is very sweet.

From a lot of other conversations in a room, they would fail.

That's because the trouble they're experiencing is in their brain.

The concussion, which is also, by the way, known as a mild traumatic brain injury, is affecting the brain circuits that process sound.

And one of the things those circuits do is filter out background noise so we can focus on a particular sound.

So they can hear perfectly well, but their concuss brain can't decipher and figure out what the sounds mean.

Exactly.

How often does this happen?

It looks like sound processing problems affect maybe 15 to 20% of concussion patients.

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