Short Wave - Aha! The Power Of A Short Rest

Episode Date: June 27, 2025

Since 2004, scientific research has shown that a full night of sleep may lend itself to a burst of insight in the morning. But what about the earlier stages of sleep? And what about just a nap? A research team based in Germany found that even a 20-minute nap could deliver a "eureka" moment, and published their findings in the journal PLOS Biology this week. Have a question about sleep? Email us at [e-mail] — we'd love to hear from you!Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave.See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Hey, short waver is Regina Barbara here. And Emily Kwong with our biweekly Science News Roundup featuring my brother from the Pacific Northwest, Ari Shapiro, from all things considered. My sister from another mister. That's right. So good to be here, especially because I hear we've got a story about naps, which I just love, how they can help solve a problem. This podcast would not be made without naps. Yes, we also have a story on an important picture of an exoplanet.

Yes, and how wildfires can impact water quality nearly a decade after they burn. All of that on this episode of Shortwave, Science Podcast from NPR. All right, all right, where do you want to start? I love any reason to take a nap. Are you about to give me another reason proven by science? It's your lucky day. You know how when you're stuck on a problem, the common wisdom is sleep on it? Yeah, sure.

Or like you wake up and have some insight you didn't have when you went to bed. Yes, Ari, science backs this up. A full night of sleep may lend itself to a burst of insight. And a group of researchers in Germany wanted to know more about the stages of sleep involved in a eureka moment. Could a nap be enough to deliver us that aha? How do you actually measure a eureka moment scientifically? Yeah, good question. Okay, so researchers invited study participants to track a group of dots on a screen and decide whether the dots were

generally moving towards one of the four corners of the screen. But there was a secret trick that made the task super easy. The correct response was paired with a collar. Without knowing that trick, though, the task was kind of tough. So in the middle of the task, the researchers let the participants take a 20-minute break in a room with the lights off, seated upon the most comfortable IKEA chair that cognitive neuroscientist Anika Lurva could find. Yeah, we also told people to sleep 30% less the night before and not consume any caffeine before. coming in at 1 p.m. So very primed to fall asleep. Yeah, exactly. Participants were also hooked up

to an electrode cap to measure their brain activity. Some stayed awake, some fell asleep. And then they were asked to return to the task and discovered something kind of amazing. Yeah, Ari, those who napped figured out the color trick at a higher frequency. And those who managed to enter the first phase of deep sleep, known as the N2 phase, had the highest frequency of insight. 86% of those deep sleepers had their eureka moment. So they cracked the color code, they solved the task, and they only napped for like 20 minutes max. Yeah, that's right. Amazing. So on the level of brain chemistry, how does deep sleep, even for a brief period of time, lead to these breakthroughs? Yeah, that's the next question. This team and others want to investigate. Anika told me the leading

theory is that deep sleep consolidates what you learned. So maybe in deep sleep, irrelevant synaptic connections are pruned away and relevant connections remain so that upon waking, that might set our brain up for a breakthrough. Yeah, but this theory, of course, would have to be, like, tested with more sleep research. Sign me up. I'm happy to be paid to sleep. Okay, next story, Gina, what is so special about this newborn baby distant planet? Yes. Okay, so it's a planet beyond our solar system. It's orbiting another star. That's what's called an exoplanet. And astronomers have found thousands of exoplanets before, but this one is special because, one, this exoplanet was actually seen in an image, which is really hard to do. And two, astronomers took this picture while the

exoplanet was still in this leftover disk of gas and dust it was formed from. The researchers published this image in the journal Nature this week. Yeah, and astrophysicist Alicia Weinberger, who didn't work on this study, said the image helps clarify a big missing piece of the planet formation puzzle. We have only a few examples of stars that have both a desk and a planet where we can really look at that interplay and how one is influencing. saying the other? And so does this new evidence fit the conventional wisdom about how planets form? Yes, yeah. So scientists have a very good hypothesis that planets form inside this disk of gas and dust. It's left over from like the star forming, actually. And these disks look like

pancakes of light around a very young star. That's why all the planets in our own solar system are in a plane. They came from a similar pancake. Yes, a very delicious pancake. But sometimes there are gaps in the disks that are thought to be created from planets forming. And until now, scientists haven't been able to capture a planet in a gap on camera. So now that it's been caught on camera, what can we learn about the exoplanet? We can learn about its atmosphere, for one, which tells us more about what it's made out of. We've talked to multiple astrophysicists for the story, and they all think that this image is like just the beginning. That eventually the James Webb Space Telescope will reveal like the whole process of how a planet forms.

Yet another insight, thanks to the James Webb Space Telescope, which is so much better than any that came before, huh? Yeah. So much. I mean, it's sensitive enough to get an image of an exoplanet this small, about 30% of the size of Jupiter. The exoplanet is still bigger than Earth, but photographing a planet formation this small is a step towards finding even smaller planets closer to the size of Earth in our galaxy. Yeah, and a planet closer to the size of Earth is more likely to be hospitable to life. Well, let's come back to Earth for our third and final story. which is about how wildfires affect water quality.

We heard about this a lot during the Southern California wildfires. What's the new insight here? Yes. So a study came out this week in the journal Nature Communications and Environment, which suggests that water impacts can linger nearly a decade after wildfire flames die down, especially when it comes to contaminants left behind by the fires like sediment or nitrogen. Decades a long time. How did they figure that out?

Yeah, the researchers analyzed hundreds of watersheds and compared areas that have been burned in wildfires to areas that were unburned. But they used data from across four decades. They collected data between 1984 and 2021, which is a big deal since most wildfire studies have looked at a smaller window of time two to three years after a fire. And a watershed, by the way, they're very important. It's an area of land that collects water from rain or snowmelt and eventually channels water into a larger body like a reservoir. watersheds provide around two-thirds of the U.S. population's clean water supply. So knowing the state of a watershed could be a good way to measure the aftermath of a fire. Yes, exactly.

I know fires are becoming more intense and more frequent due to human-caused climate change. What kinds of contaminants are sticking around long after a fire? Yeah, the authors saw that carbon and phosphorus stuck around for up to like five years after a fire, while nitrogen and sediment were detected in the watersheds for up to eight years, all of which, in excessive amounts can be harmful to humans and ecosystems. But public water utilities filter water before it reaches our faucets. So what does this mean for those of us who are, I don't know, taking showers and drinking water? Yeah.

So one of the steady authors, Ben Livna at University of Colorado Boulder, said that listeners shouldn't worry about water quality. But water utility companies should be extra aware of these contaminants for a long time after a wildfire takes place. They should perhaps pivot to use a new supply, depending on where the water should. that is. Or use this information to be better prepared for future fires and help build water systems that are more resilient towards fire. And this data could help them do that. Which is going to be even more necessary as the planet heats up.

Yeah, definitely. Thank you so much for hanging out with us. It's always so fun and educational. You can hear more of Ari Shapiro on Consider This and PR's afternoon podcast about what the news means for you. And while you're checking out Consider This, why don't you hit follow on the NPR shortwave feed on the NPR app or whatever podcasting platform you wish. So you'll never miss an episode. And if you like this one, share it with a friend. This episode was produced by Megan Lim and Rachel Carlson.

It was edited by Rebecca Ramirez and Patrick Jaron Watanan. Tyler Jones checked the facts. Ko Takasugi, Chernoen, and Tiffany Vera Castro were the audio engineers. I'm Emily Kwong. And I'm Regina Barber. Thank you for listening to Shortwave, the science podcast from NPR.