Hey there, it's Stephen Dubner.

We recently got an email from a listener who wondered if the recent wildfires in the

southeastern United States were going to affect the final exam scores for high school

and college students, not because students were displaced by the fires, but because the

wildfire smoke might have affected their brains.

This listener had apparently heard an episode we made a few years ago called This Is Your Brain on

Pollution. So we've decided to replay that episode for you today with updated facts and figures.

As for whether this year's test scores in the Southeast were

affected, that sounds like an excellent research question for an enterprising investigator.

If anyone out there decides to do that research, let us know. We're at radio at

freakonomics.com. As always, thanks for listening.

Thank you. As always, thanks for listening. It's worse than cigarette smoking.

It's worse than wars.

It's worse than auto accidents.

Wow, what's worse than wars and car crashes and smoking?

Here, I'll give you a hint.

Imagine you were getting ready to leave your house for work or school, maybe to go for a run.

There is some standard information that most of us seek out before leaving home.

There's this.

We've got partly sunny skies. It's 85. South winds at 14.

And there's this.

We've got multiple accidents, stalled vehicles, causing major delays.

...