You're listening to Shortwave from NPR.

Hey, shortwaiver is Regina Barbara here.

And at Shortwave, we love us some brains, which is why we've had a lot of conversations over the years with NPR's neuroscience reporter John Hamilton.

John is retiring.

So today he's going to tell us about some of the most memorable

brains he's come across, excluding mine, in the past couple decades. Hey, John.

Hey, Gina and Gina's brain. I am calling this episode my favorite brains. And I'm guessing

there's a lot. I mean, you've been on the brain science beat for 15 years. Is that right?

Yeah, at least that long.

There's so many brains, right?

I have reported on those tiny brain organoids that grow in a dish.

Those are my favorite.

Fruit fly brains, mouse brains, artificial brains, and some really memorable human brains.

Let me give you an example.

So back in 2015, I did a story about a man who was missing a part of the brain called the cerebellum.

Okay. I think I know what it is, but just to remind me, what is the cerebellum?

It's this structure at the base of the brain that's about the size of your fist. It contains more than half of all the neurons that a typical person has. And it is absolutely critical to passing a roadside sobriety test. Okay. Why is that?

Because the cerebellum is what lets you balance on one foot or keep your eyes on a moving target, like say hypoth, the pen that a police officer is moving from side to side in front of you. And alcohol pretty much disables the cerebellum.

Okay, that's good to know. I think I knew that, actually. The guy did the story about Jonathan Keller, her. He never had a working cerebellum in the first place.

So did that mean he had problems with balance and coordination?

He did, but he also had problems with all these other brain functions that turn out to rely on the cerebellum.

So you have like speech and language.

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