How do synthesizers work?

Ever wondered how synthesizers make all those bleep-bloop-blorps? Well, this episode has got you covered.


Synthesizers are a very recent invention, especially when you compare them to acoustic instruments, like pianos and guitars. In this episode, we learn how these machines with keys, knobs, switches, buttons and sliders actually make sound. We’ll also travel back to the 1960’s and hear how synth pioneers like Bob Moog helped bring these sound making devices into the mainstream. Plus, we’ll check in with Suzanne Ciani, who has been using her synthesizer to create iconic sounds for movies, television and video games for over 50 years! All that plus a striking Mystery Sound and Moment of Um that answers the question: Do airplanes have a speed limit?

Suzanne Ciani | System 55

Why is it so hard to break a habit?

If habits are really stuck, we don't think much about them -- we just do them! Some habits are good (like brushing your teeth in the morning) and others are not so good (like biting your nails). Today we find out what parts of our brains help us form habits and why it's actually super useful to not have to think so hard about everything. 


If habits are really stuck, we don't think much about them -- we just do them! Some habits are good (like brushing your teeth in the morning) or not so good (like biting your nails). Today we find out what parts of our brains help us form habits and why it's actually super useful to not have to think so hard about everything. Gungador tries to break a bad habit, and we find out the best tips for ditching habits we want to leave behind. Plus: A brand new mystery sound and a Moment of Um that answers the question: "How do 3D glasses work?"

Smash Boom Best: Flowers vs Rainbows

We’ll be back with new episodes in January. But we wanted to share another show with you that we’ve been working on -- Smash Boom Best.


We’ll be back with new episodes in January. But we wanted to share another show with you that we’ve been working on -- Smash Boom Best!

It’s a debate show where we take two cool things, smash them together and let you decide which one is best. Today we’re going to share with you an excerpt from a heated, fierce debate featuring our very own Sanden Totten.

Sanden is repping team flowers and our good friend Joy Dolo, host of Forever Ago, is repping team rainbows.  To hear the rest of the debate, find Smash Boom Best wherever you listen to podcasts. There are over 30 debates ready for your binge listening this holiday season! Play along at home by yourself -- or with your family! You can find score sheets and other fun stuff at smashboom.org

Bones from the inside out

Bones! They’re spooky. They’re creepy. They’re utterly fascinating! This episode we dig up the science behind skeletons. 


Bones! They’re spooky. They’re creepy. They’re utterly fascinating! This episode we dig up the science behind skeletons. We’ll look at how our bones grow, what happens when we break a bone and why bones last so long. Plus, we’ll meet a talking skeleton who will help us bone up on bone trivia! And we have a mystery sound to tickle your auditory ossicles and a Moment of Um that answers the question: Why does time fly when you're having fun?

Why do siblings annoy each other?

How does your brother or sister know just how to annoy you? It’s like they were born to do it!


Having a sibling is a special thing -- but, wow, can they be annoying! In this episode we’ll look at why our brothers and sisters are so good at pushing our buttons. Plus, is there any truth to the idea that oldest kids are the most mature and the youngest ones are the most charming? We’ll look at the science of personality and birth order. We also visit a sibling drive-thru, get quizzed about animal relationships and answer this question in our Moment of Um: why does rain come in small droplets?

How do flu vaccines work?

Flu Vaccines

The flu shot changes every year. But why is the flu special, if other illnesses have much longer-lasting vaccines? This episode takes us into the world of viruses and immunity?


The flu shot changes every year. But why is the flu special, if other illnesses have much longer-lasting vaccines? This episode takes us into the world of viruses and immunity.

A friendly lymphocyte fills us in on how flu shots work, and science journalist Anna Rothschild shares how vaccines started around the world. We'll hear from some virus-busting detectives to see how scientists solve the case of how to make next year’s flu shot as effective as possible. Author Maryn McKenna will stop by and drop some flu knowledge, too!

Get your ears ready for a good, thumping mystery sound, and a new Moment of Um: how do straws work?

Brains On! Science podcast for kidsThe flu shot changes every year. But why is the flu special, if other illnesses have much longer-lasting shots? This episode takes us into the world of viruses and immunity.
A friendly lymphocyte fills us in on how flu shots work, and science journalist Anna Rothschild shares how vaccines started around the world. We'll hear from some virus-busting detectives to see how scientists solve the case of the next year’s flu shot. Author Maryn McKenna will stop by and drop some flu knowledge, too!
Get your ears ready for a thumpingly good mystery sound, and a new Moment of Um: how do straws work?

Past, present and future: Using time to understand this pandemic

We're documenting history and digging into why has time seemed to slow down and speed up during the pandemic?


Past, Present And Future_ Using Time To Understand This Pandemic

If time feels weird to you lately, you’re not alone. The pandemic has changed the pace of life for people around the world. We’ll talk to a psychologist about how our sense of time works. We’ll look back into the past to see how a similar pandemic played out 100 years ago. Plus, we’ll ask experts to tell us what they think life will be like six months from now. 

Oh yeah, and virus podcasters Kara and Gilly are back to tell you how you can be a part of history! Warning: Boogers are involved. Our Moment of Um answers the question: why do your arms move when you walk?

Scrapbook to remember what it's like right now

Smash: When continents collide!

How are mountains made? What causes an earthquake? How does hot lava come bubbling up? The answer in each case is…tectonic plates!


How are mountains made? What causes an earthquake? How does hot lava come bubbling up? The answer in each case is…tectonic plates!

These are giant, moving slabs of rock covering the Earth’s surface. When they slide past or smash into each other it shakes the planet. But, they also helped shape the land we live on.

Find out how they work with an extreme cooking demonstration (you’ll never see peanut M&Ms the same way). Meet the scientist who thought long ago all the continents were smushed together in a super-continent (spoiler: he was right!). Plus an interview with a USGS scientist about what our planet might look like in a million years.

All that plus a mystery sound and a Moment of Um about stinky breath. Listen up and rock on!

How are mountains made? What causes an earthquake? How does hot lava come bubbling up? The answer in each case is... tectonic plates! These are giant, moving slabs of rock covering the Earth's surface. When they slide past or smash into each other it shakes the planet. But, they also helped shape the land we live on. Find out how they work with an extreme cooking demonstration (you'll never see peanut M&Ms the same way). Meet the scientist who thought long ago all the continents were smushed together in a super-continent (spoiler: he was right!). Plus an interview with a USGS scientist about what our planet might look like in a million years. All that plus a mystery sound and a Moment of Um about stinky breath. Listen up and rock on!

The Continental Divide at the Þingvellir National Park in Iceland.

Map of tectonic plates 210 million years ago

Behind the scenes: See how we make the show

Like so many people in the world right now, we’re stuck in our homes. That means we’ve had to figure out how to make episodes without being in soundproof studios. This episode takes a look at how we’re doing that.


A listener asked how making  Brains On is different during the pandemic. So with this episode we're giving you a peek into how we're making the show while staying safe. Spoiler alert: we're doing it all from our homes!

What's the best way to record crystal clear sound at home? (Hint: Lots of soft surfaces!) How do we make sound effects? How do we get all the animals, humans and machines in our homes to keep it down while we tape? Plus: We asked our co-hosts to share what it was like for them to record and episode from home. All that, plus a brand new mystery sound and a Moment of Um that answers the question: how do rocks form?

Co-host Brooklyn gets ready to tape an episode of Brains On!

The buzz on bees, pt. 2

Pollination takes center stage in the second of our two-part bee episodes.


In this second episode on bees (a bee-quel, you might say!) we’re taking a look at pollination: the many pollination talents of different bees, why pollination is so important, and what you can do to help wild bees! 

The tables are turned in the Mystery Sound department: our beekeeping cohosts have a sound for Menaka and Sanden to guess! And the Moment of Um answers an age-old stumper: how are alligators and crocodiles different?

The buzz about bees, pt. 1

We’re going inside the beehive to find out why bees buzz, learn about their stingers and so much more. 


We’re making a big buzz about bees! Our pollen-collecting friends get so much done, and we’re taking a look at how they live. We’ll bust some bee myths and meet some honeybees for a look at life inside the hive. Our mystery sound is from a listener (here’s a hint: they recorded the sound in Alaska!), and our Moment of Um answers a buzzworthy question: Why do beehives look like hexagons? And! One episode on bees just isn’t enough. We’ll be back next week with more buzz on pollination.

The buzz on bees, pt. 1

Stars: Twinkling, glowing, giant balls of gas

Listen to hear how the origins of our solar system involve a kind of cosmic pancake. And, how the Milky Way plays an important role in cultures all over the world.


Those tiny pinpoints of light glittering in the night sky are actually incredibly distant, giant, churning balls of gas. They produce huge quantities of light and heat. In this episode, Mars interviews the biggest star in his eyes: the sun! We also ask astronomer Moiya McTier to help us count all the stars in the universe. And we'll hear a couple of the stories that people here on earth tell about the stars. Plus, a brand new mystery sound and a Moment of Um that answers the question: how do whales drink?

What makes gross things gross?

Fair warning: Today we’re gonna get gross! We’re talking sounds, smells, and tastes that some people might find repulsive. But we're asking: why? What's the purpose of disgust? Is it something we're born knowing or do we learn to dislike things? When will entomophagy (the eating of insects) catch on everywhere? Plus: A brand new Moment of Um answers the question "Why do worms come out when it rains?"


Fair warning: Today we’re gonna get gross! We’re talking sounds, smells, and tastes that some people might find repulsive. But we're asking: why? What's the purpose of disgust? Is it something we're born knowing or do we learn to dislike things? When will entomophagy (the eating of insects) catch on everywhere?

Plus: A brand new Moment of Um answers the question "Why do worms come out when it rains?

Fair warning: Today we’re gonna get gross! We’re talking sounds, smells, and tastes that some people might find repulsive. But we're asking: why? What's the purpose of disgust? Is it something we're born knowing or do we learn to dislike things? When will entomophagy (the eating of insects) catch on everywhere? Plus: A brand new Moment of Um answers the question "Why do worms come out when it rains?"

Eric Middleton at the Minneapolis City Qualifiers - American Ninja Warrior 2018

Poop party: Answers to your poo question

We know you have a lot of poo questions because you’ve sent many, many of them to us. So we’re finally bringing you the poo answers! It’s a poop party! 


Warning! This episode is all about the fascinating and gross world of doo doo.

We know you have a lot of poo questions because you’ve sent many, many of them to us. So we’re finally bringing you the poo answers! It’s a poop party!

We’ve invited scientists to tell us about weird animal feces. (It’s true! Wombats have cube-shaped poop!)

We tune into a news channel all about dookie (see the Bristol Stool Chart here!).

We hear from our favorite “poo-tuber” Taylor the Turd about how some poops are helping fight serious illnesses. (Remember Taylor? Here’s her first appearance!)

Plus, a sorta stinky Mystery Sound and a Moment of Um answering a question: why is pee yellow?

Poop Party: Answers to your poo questions

Introducing: Million Bazillion

We’re thrilled to share a brand new show with you. It’s called Million Bazillion and it’s all about money -- how we earn it, how we save it and how we spend it.



We’re thrilled to share a brand new show with you. It’s called Million Bazillion and it’s all about money -- how we earn it, how we save it and how we spend it.

In the first episode you’ll travel back thousands of years to learn the ways people got what they needed before money was invented. Back then some people traded goods, others made pacts to share what they had. We’ll also meet the king who came up with the idea for coins. Plus, Kristen Bell designs her own money!

This show is a collaboration between Brains On and Marketplace. It’s hosted by Jed Kim with Bridget Bodnar. You can listen to more episodes here, or subscribe at Apple Podcasts, Spotify, Google Podcasts, or wherever you get your podcasts.

Masks and mouth mist: What we know about the coronavirus now

In this episode, we find out why masks are an important tool in the fight against this new coronavirus. We’ll also talk about this unusual time we’re living through and how to deal with the uncertainty of it all. Plus: Kara and Gilly debut their first single. They’re hoping it’s a viral sensation (pun very much intended). And, of course, a new mystery sound and a Moment of Um that answers the question: Why do sharks have to keep moving to stay alive?


Masks and Mouth Mist_ What We Know About The Coronavirus Now Transcripts

Since the world first learned about this new coronavirus at the end of 2019, we’ve been watching science happen in real time. Scientists all over the world are studying this virus and learning how to protect us from it. As they learn new things, we learn new things too.

One thing they’ve learned is how this virus spreads. The primary culprit is droplets from our noses and mouths. That’s why masking up is so important to protect our communities.

We’ve also been hearing from a lot of listeners wanting to know about the future: when will the vaccine be ready? what will it be like at school? when will things go back to normal? We're going to do our best to answer some of these questions in our next coronavirus episode. But they don’t have concrete answers right now.

Right now, trying to look a month, or a year into the future is hard. We call this feeling of not knowing what will happen -- uncertainty. And it’s hard to deal with.

Our brains likes being able to predict what’s going to happen because it makes us feel safe. When we feel unsafe, that’s when anxiety kicks in. 

One way to deal with this anxiety is to focus on the present -- what’s happening right now. 

It’s also important to let yourself feel your feelings and know you’re not alone in them. It’s normal right now to feel frustrated, or angry, or sad, or all of them at the same time. But also try to think about the moments you have that are fun, and the times you feel contentment and happiness.

If you’re having trouble staying focused on the present there are some tricks you can try:

Look around you and make a list in your head of everything you see that is green.
Try to think of all the character’s names in your favorite book or tv show
Take deep breaths -- inhale for four counts, hold that breath for four, and then exhale for four
Distract yourself by going outside, or watching a movie or reading a book. 

If you’re still having trouble keeping your mind off the “what ifs” it’s great to talk to your parents or another adult you trust.

There are always people who want to help you. If you need help and aren’t sure who to talk to, you can call 800 273-8255. It's a free phone call, and people are there all the time, ready to listen and help.


A kid riding a bike in a helmet and face mask

The world of tiny robots

Robotics is a huge industry, but in this episode we focus on the smallest part: tiny robots!


We’re talking all about teeny, tiny robots in today’s episode. You know, the ones that are as light as a postage stamp and as look like insects? They may be small, but these robots can still take in information and make decisions on their own. Find out how bees and cockroaches are teaching us about the future of small robots and what big tasks they might take on. There’s also a new Mystery Sound to rattle your ears. Plus a moment of Um that answers the question: Why does the sun stay in one place?

Why do kids have more energy than adults?

It’s the showdown of showdowns: kids vs. adults. Who has more energy and why?


We’re taking on an age-old question today: Do kids have more energy than adults? Breakfast tacos, caffeine, an energized DJ and an epic family battle. This episode has all that and then some. Discover how we turn food into energy at an awesome taco party. Then pump up the jams with DJ Thyroid. Speaking of music, get ready for a song from Lake Street Dive’s Mike Olson. And just when you think the show might be out of energy, we engage in an out-of breath competition between a girl and her parents. Plus, there’s a brand new Mystery Sound and a Moment of Um about why we lose our voices sometimes.

A tired dad lays on the couch while kid plays

Why does green mean go? And other color conundrums

Why do certain colors mean different things? We’re looking at green, red and yellow in today’s episode.


Why does green mean go? Transcript

The world is full of color, but how do our eyes see it? In this episode we’ll explain how color vision works, complete with a journey to a jazz club in the back of your eye. We’ll also look at the cultural meanings of the color red, we’ll find out about a new type of blue, and we’ll find out why stoplights use green to mean go. Our Moment of Um tackles the question, “why are bees black and yellow.”

Injustice and Anger: Understanding your emotions

A lot of us are angry right now, with good reason. We’re seeing people treated unfairly because of racism -- that’s when people don’t like someone’s race or the color of their skin. In this episode we’ll talk about how anger can be a useful emotion and can be used to push for change. We’ll also revisit parts of our 2019 series on emotions, including an explanation of the hormones behind anger, why some of us are quicker to anger than others and what we can do when we feel overwhelmed by our feelings. 


A lot of us are angry right now, with good reason. We’re seeing people treated unfairly because of racism -- that’s when people don’t like someone’s race or the color of their skin.

In this episode we’ll talk about how anger can be a useful emotion and can be used to push for change. We’ll also revisit parts of our 2019 series on emotions, including an explanation of the hormones behind anger, why some of us are quicker to anger than others and what we can do when we feel overwhelmed by our feelings.

Plus, our Moment of Um tackles the question, “What happens when lightning strikes water?”

If you want to talk to your kids about race but don’t know where to start, we suggest reading this article by pediatricians Dr. Jacqueline Dougé, & Dr. Ashaunta Anderson or Talking to Kids About Race by Heather Greenwood Davis.

There are great books to help your family start a conversation about race. Here's a list from Embrace Race, or try Brown Bookshelf's Generations Book Club.

Introducing: Julie's Library

We're very excited to share an episode of a brand new podcast we've been working on called Julie's Library. It’s hosted by the legendary, the one and only, Julie Andrews. Every week, she and her daughter Emma Walton Hamilton read from their favorite children’s books. 


Today we're really excited to share an episode of a brand new podcast we've been working on: Julie's Library. It's hosted by the legendary, the one and only, Julie Andrews. Every week, she and her daughter read from their favorite children’s books. And the story in the episode we're sharing today is called Marilyn's Monster by Michelle Knudsen. It's a lovely and funny story -- and we hope you enjoy it as much as we do!

Coronavirus: How to be a helper from home

News and updates about this coronavirus can sometimes feel overwhelming. One way to counteract that is to help. Here are a few stories about people helping and how you can pitch in.


Coronavirus_How To Be a Helper From Home Transcript

We’re all doing our best to stay safe from coronavirus, but is there anything we can do for others as well? In this episode we look at some ways you can help from home, like by making masks, donating to food banks or writing letters. Two stars of the World Handwashing Federation stop by to explain the science of how water actually dries out our hands. Plus, Kara and Gilly interview science journalist Carl Zimmer on the weird world of viruses, including some viruses that help people! 

There’s a listener-submitted mystery sound and this week’s Moment of Um tackles the question: how do seashells get their shape?

Thinking ink: The scoop on this colorful stuff!

Ink is so much more than quills and caligraphy. We use it to write, to color, to print — there are even animals that use it.


Ink is amazing. It captures our thoughts, comes in many colors and is even made by animals! In this episode we explore the history of this special substance. We’ll also talk squid ink with biologist Sarah McAnulty and explain how tattoos work.

Plus, your poems about ink! Obviously there’s also a Mystery Sound and a Moment of Um that answers the question: what happens when we pour salt on snails?

Mystery Sound Extravaganza 2020

From the depths of the ocean blue to the tops of the mountains true, Mystery Sounds abound. Take a listen, and try to guess!


You don’t have to search far to find amazing Mystery Sounds. If you listen, you can find them in every room of your house. Today’s episode is chock full of these audible wonders. They are cotton candy for the ears! They are the notes to make your tympanic membrane sing!

It’s time for the Mystery Sound Extravaganza! An episode made up of nothing but Mystery Sounds, most of them recorded by our amazing listeners.Plus, today's Moment of Um answers this stumper: when your eyes are closed, are your pupils big or small?

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