Hey, it's Guy here. So have you ever wondered what makes certain ideas, brands, or even behaviors catch fire?

Well, today on the show we're exploring how and why everything from laughter to viruses to viral ideas

have the power to spread. This episode is called How Things Spread, and it originally aired in March of 2016.

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The true nature of reality beckons from just beyond those talks, those ideas adapted for radio.

From NPR. I'm Guy Ross. So a few weeks ago, we were talking with a research scientist named Sophie Scott.

Hi speaking. Sophie works in London. Oh, we live. There's this recorded. And we were recording, of course.

Fantastic. Just outside check. It would be crazy if it was live. And now let's take your calls for Sophie Scott.

Let's open up the lines. Okay. Now that sound.

What happens to your brain when you hear that is exactly what Sophie studies as a cognitive neuroscientist.

So I study, I study human brains, but I'm interested in what we're doing right now.

You know, we can't see each other, but we are having, you know, perfectly fluent conversation.

Right. And I'm interested in how that goes on in terms of perception and production.

And I'm interested in the verbal stuff that we do. And also in the other noises we make with our mouths.

And one noise in particular that Sophie focuses on is laughter. And why like a cold or even a yarn?

There's something contagious about it. So yawning is very like laughter in this respect.

You can catch it from somebody and it will much more likely to catch it from somebody you know

than someone you don't know. Okay. So to set this up a little bit more,

you might remember this viral video that went around a couple years back.

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