Xuan June’s hearing aids have kept her company for pretty much her entire life. They go with her to school, tag along for a ride while she skateboards and sit snugly while she draws and dreams up goth-cute fashion designs.

In this episode, Xuan June is getting fitted for a new pair of hearing aids — and she’s invited Molly to come with her! Together they learn all about how these cool superpowered devices work. Plus, we find out how sound travels and get a chance to guess TWO mystery sounds.

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SUBJECT 1: You're listening to Brains On! where were serious about being curious.

SUBJECT 2: Brains On! is supported in part by a grant from the National Science Foundation.

MOLLY BLOOM: Xuan June is 8 and 1/2 years old. I met her at her house in Durham, North Carolina. And the first thing you should know about her is that she's really into fashion. Her drawings cover every wall of her bedroom. And she has notebooks full of fashion design she's created.

XUAN JUNE: My thing, my hashtag, my whatever you call it. My being of life-- no-- is goth cute.

MOLLY BLOOM: This means she loves to wear black but also like some sparkles and some pops of color. Her fashion designs showcase all different styles.

XUAN JUNE: And this was one of my first drawings that I made with pants that actually looked good to me.

MOLLY BLOOM: I like them. Very stylish.

XUAN JUNE: This was like right when I was, like, learning about eyebrows because before, I didn't do, like, eyebrows.

MOLLY BLOOM: Xuan June makes clothes for her dolls out of socks and hot glue. And she has two cats.

XUAN JUNE: Shadow is all black, and Luna, she's black and white. She has like a white, sort of, tuxedo. And in the front, she has boots. And in the back, she has socks.

MOLLY BLOOM: She knows some sign language and speaks Vietnamese.


MOLLY BLOOM: And she's worn hearing aids for pretty much her whole life. I got to hang out with her in her hometown to learn how hearing aids work. And she's here in the studio with me today to help me explain.

XUAN JUNE: I can't wait.


MOLLY BLOOM: You're listening to Brains On! from APM Studios. I'm Molly Bloom. And my co-host today is Xuan June from Durham, North Carolina. Hi, Xuan June!

XUAN JUNE: Hi, Molly!

MOLLY BLOOM: Today's episode was inspired by a question that you sent to us. What was that question?

XUAN JUNE: My question was, how do hearing aids work?

MOLLY BLOOM: It's a very, very good question. I'm wondering how you came up with it.

XUAN JUNE: I came up with this question because I know some stuff about how ears and hearing work, but back then, I didn't know that much about the science of hearing aids.

MOLLY BLOOM: So you were hearing aids pretty much every day.

XUAN JUNE: Mm-hmm.

MOLLY BLOOM: Do you get kids asking you questions about them?

XUAN JUNE: Kids ask a lot of questions about my hearing aids. But the main question I get is, what are those things in your ears? So I have to explain to every kid who asks why I need them and what they are.

MOLLY BLOOM: So I'm guessing you're pretty good at that now since that must happen a lot.


MOLLY BLOOM: So how do you respond to them?

XUAN JUNE: I respond like, well, my hearing is a little-- I can't, like, hear as loud as most people can. So I need my hearing aids to help me hear better.

MOLLY BLOOM: That's a very good explanation. So can you describe-- since this is a podcast, can you describe what your hearing aids look like?

XUAN JUNE: They're basically like something that's shaped, like, to my ear that fits in my ear. But that's the hearing-- like the mold, the ear mold. And then there's like a tube that comes up behind my ear that actually connects the real technology part of it that's less behind my ear and that actually is the thing that connects with Bluetooth and just other stuff to help me hear better.

MOLLY BLOOM: Cool. So it's basically like two main parts. There's the part that goes inside, sort of nestles in your ear. And that you call that the ear mold, right?


MOLLY BLOOM: And then that's connected with a tube?


MOLLY BLOOM: To the technology. And that rests behind your ear?

XUAN JUNE: Mm-hmm.

MOLLY BLOOM: There's a little tube that goes in to your ear that sort of pipes that louder sound into it?


MOLLY BLOOM: Got it. So how often do you get new hearing aids?

XUAN JUNE: I get new hearing aids about every two years.

MOLLY BLOOM: We're going to hear all about that in just a little bit. But before we dive into how hearing aids work, let's take a dive into an ear.

XUAN JUNE: I don't know. Those things can get pretty waxy and sticky.

MOLLY BLOOM: We don't have to actually go inside because I have our nifty zoom ray right here!

XUAN JUNE: Oh yeah!

MOLLY BLOOM: Care to do the honors?



MOLLY BLOOM: All right. We're zoomed in now on the outer ear.

XUAN JUNE: That's the bendy, squishy, swirly part of your ear that sticks off your head.

MOLLY BLOOM: This is also called the auricle or the pinna. Your parts have very excellent names that we hardly ever use. So now's the time, everyone.

XUAN JUNE: The pinna is made of skin and cartilage.

MOLLY BLOOM: Cartilage is the flexible tissue that allows your ears to bend.

XUAN JUNE: It's also when your nose, in your knees and elbows, and other places in your body that need to be strong but bendy.

MOLLY BLOOM: All the swirls and bends in your outer ear also have names, but we don't need to get into those now.

XUAN JUNE: OK. So moving on.

MOLLY BLOOM: OK, fine, I'll tell you. The outer rim on top is the helix, underneath is the antihelix. Then the concha, the tragus, antitragus, and the lobule.


MOLLY BLOOM: Anywho. Now let's zoom into the ear. Xuan June, if you please.

XUAN JUNE: Happy to.


MOLLY BLOOM: Now, as we wind our way through the ear canal, what's underneath the skin goes from bendy cartilage to very firm bone.

XUAN JUNE: And at the end of this canal is the ear drum.

MOLLY BLOOM: It's really just a thin piece of tissue that stretches across the end of your ear canal like the top of a drum.

XUAN JUNE: This is the first stop for sounds entering your ear.

MOLLY BLOOM: Oh, Xuan June, point the zoom ray at the air by my mouth for just a sec.



MOLLY BLOOM: Zoom like way in.



XUAN JUNE: Holy cats! I can see all the molecules that make up the air.

MOLLY BLOOM: Yeah! Even though air looks clear to us, it's made of stuff-- teeny, tiny molecules.

XUAN JUNE: Molecules are the building blocks that make up everything. This microphone, my black nail polish, the water, the air, everything!

MOLLY BLOOM: Right. And sound is made when air molecules vibrate and bang together. So when I go, ha! The vocal cords in my throat vibrate, which causes the air molecules around them to move at a certain speed. We call that speed the frequency.

XUAN JUNE: Oh, yeah! Different frequencies make different pitches. So if the molecules are vibrating really fast--

MOLLY BLOOM: At a high frequency.

XUAN JUNE: --the sound is high.

MOLLY BLOOM: And if the molecules are vibrating slower, the frequency is lower than the sound is lower.

XUAN JUNE: And depending on how loud a sound is the molecules will vibrate with more or less strength.

MOLLY BLOOM: So when the sound leaves my mouth it causes a little chain reaction in the air, kind of like knocking dominoes over but invisible. First, the air molecules by my mouth smack into each other, then those molecules hit into the ones next to them, and on and on until those vibrations reach the air molecules next to your eardrum.

XUAN JUNE: This chain reaction is called a sound wave.

MOLLY BLOOM: And when a sound wave hits this drum in your ear, it vibrates. But that's not where the story ends. Those vibrations pass onto other parts of the ear. The ultimate destination for these vibrations are teeny tiny hair cells inside the inner ear.

XUAN JUNE: Teeny tiny means we need to zoom again.

MOLLY BLOOM: Zoom away.


These teeny tiny hair cells are topped with even teenier cells that stick straight up. They're so small that you can only see them with a microscope.

XUAN JUNE: And they kind of look like the pipes on a pipe organ or bristles on a toothbrush.

MOLLY BLOOM: Different hair cells specialize in picking up different sound frequencies. It's sort of like how a lock only opens with the right key.

These cells only react if they feel the right frequency. So when a hair cell senses the frequency it's designed to pick up, it sends a signal to the brain and the brain figures out that it's hearing a sound.

XUAN JUNE: So next time you hear a dog bark.


MOLLY BLOOM: Or a dog fart, for that matter.


XUAN JUNE: Think of the mighty journey that soundwave had to take to be heard.

MOLLY BLOOM: For people with some kinds of hearing loss, these tiny hair cells inside the ear might be damaged, meaning they might not be able to hear some frequencies at all, or in your case, Xuan June, the hair cells have a harder time picking up quieter sounds. And this is where hearing aids come in.

SUBJECT 3: Brains, brains, brains on.

MOLLY BLOOM: Now, Xuan June, when we talked last time you told me that your hearing aids are kind of like a superpower. Can you tell me a little bit about that superpower?

XUAN JUNE: Sure. My superpower is that I have a hearing aid or hearing aids. It amplifies the frequencies that are harder for me to hear because the hairs that hear those frequencies didn't grow or got damaged. My hearing aids help me hear those specific sounds. It's sort of like a superpower because I can hear things sort of louder than everyone else can.

MOLLY BLOOM: That is very cool. So basically the way hearing aids work is that they take in those sounds around you and bump up the volume so it's easier for you to hear them, right? Did I get that right?


MOLLY BLOOM: So what does it feel like when you're wearing your hearing aids versus not wearing your hearing aids?

XUAN JUNE: When I'm not wearing my hearing aids, the world sounds sort of muted. And when I'm wearing my hearing aids, the sounds I already could hear before sound, like, a lot richer. Like the difference between eating stale biscuits versus fresh biscuits. And then the sounds that I couldn't hear without my hearing aids are like a whole-- like, hearing basically like a whole new world.

MOLLY BLOOM: That's so cool. That's such a good way of describing it. So what are some of the sounds that are really hard to hear without your hearing aids in?

XUAN JUNE: Like birds chirping. Like the bells on a cat toy. And, like, high frequency sounds.

MOLLY BLOOM: So when we were talking last time, you described it as sort of like surrounded by a dotted line?

XUAN JUNE: Uh-huh. So, like, basically you know it's supposed to be there but you can't hear it. Like, you know it's there but you can't hear it. Like, but your brain sort of makes that sound up but it can't copy the sound that you know you're supposed to be hearing exactly.

MOLLY BLOOM: Gotcha. Because, like, you've heard it with your hearing aid, and so your brain's kind of like, I've heard this before, but, like, I'm not hearing it right now.

XUAN JUNE: Yeah. And your brain sort of is scared of you missing something. So your brain makes up the dotted line, basically the skeleton of the sound, but it isn't able to copy it exactly.

MOLLY BLOOM: That is very, very cool. So when babies are born, they're given a few tests to see how their bodies are working now that they're out in the world. One of these tests checks they're hearing.

XUAN JUNE: Yeah. When I got this test as a baby, my parents and doctors learned that there was some sounds that were tough for me to hear.

MOLLY BLOOM: And then later, you got some more specialized tests and got your first pair of hearing aids.

XUAN JUNE: Yep. And as I grow and change, so do my hearing aids.

MOLLY BLOOM: Before we learn more about all the awesome things your hearing aids can do, it's time for the mystery sound.

SUBJECT 4: Mystery sound.

MOLLY BLOOM: You ready?

XUAN JUNE: Mm-hmm.

MOLLY BLOOM: Here it is.


What is your guess?

XUAN JUNE: It sounded a lot like sloshing water. So maybe like in a bathtub? But I also think I heard like a thunk in there. So like maybe like taking out the thingy wingy that blocks the drain?

MOLLY BLOOM: Oh, yeah. The stopper? Something like that?

XUAN JUNE: Yeah, the stopper. Like, maybe like in a bathtub. Like you're swimming and then you take out the stopper.

MOLLY BLOOM: I think I do prefer the term thingy wingy, though. So we'll just call it that. That is a really good guess.

XUAN JUNE: Thank you.

MOLLY BLOOM: Well, we will listen to it again after the credits and give you another chance to guess. But we're not done yet. It's only fitting that an episode all about sounds and hearing would have two mystery sounds. And this next one is a mystery sound that you sent to us, Xuan June. So this one is for our listeners to guess. Here it is.


So Xuan June, do you have any hints you'd like to give our listeners?

XUAN JUNE: It involves my healing superpower.

MOLLY BLOOM: Excellent hint. We will have Xuan June reveal the answer right after this short break.


Hey, friends. We're working on an episode all about friendship.

XUAN JUNE: Friendship is an amazing part of being a human.

MOLLY BLOOM: And listeners, we want to hear from you. Tell us what makes a good friend? Record your thoughts. We'll be featuring some of your answers on this upcoming episode.

XUAN JUNE: Send them to us at brainson.org/contact.

MOLLY BLOOM: And while you're there, you can send us questions you'd like us to answer on the show, mystery sounds, and drawings. brainson.org/contact is where we got this question.

SUBJECT 5: What do zookeepers feed bigger snakes such as pythons?

XUAN JUNE: You can find an answer to that question on the Moment of Um podcast.

MOLLY BLOOM: It's a short dose of facts and fun every weekday. Find it wherever you listen to podcasts.

XUAN JUNE: And keep listening! You're listening to Brains On! from APM Studios. I'm Xuan June.

MOLLY BLOOM: And I'm Molly. Let's go back to Xuan June's mystery sound one more time.


We'll let you think about it for a second. OK, Xuan June, what is the answer?

XUAN JUNE: The answer is the feedback from my hearing aid and, like, turning on. There is like this click sound when you turn it on, like you connect the battery to the rest of the hearing aid. And there's also this little melody that you heard before that that tells me that it's on and working so that I know.

MOLLY BLOOM: That's a very pleasant melody. I like it. When does that feedback sound happen in your day to day life?

XUAN JUNE: It happens when the ear mold is not fitting tightly in my ear and the microphone and the hearing aid is hearing the sound loop back on itself from the gap. So when this happens, I know I need new ear mold because it's loose in my ear or I know I need to just shove it back in there.

MOLLY BLOOM: Nice. So does that happen a lot or just like occasionally?


MOLLY BLOOM: Is that a sound that you find irritating? Do you like-- you don't think anything of it because you hear it all the time? Like, how do you feel about that sound?

XUAN JUNE: I mean, my parents find it annoying, honestly. But for me, it's-- I don't really mind it that much. I sorta like it.

MOLLY BLOOM: So can you tell us a little bit sort of about your daily hearing aid routine? We heard you turn it on. And so, like, what happens when you wake up in the morning?

XUAN JUNE: So say it's a school day and I have to put my hearing aids in. I wear them for the rest of the day until it's nighttime, and I take them out. Sometimes my mom or dad have to clean the molds-- the molds, not the technology part because they can't go in water-- the molds in soap and water with like a toothbrush with bristles. And then I put them in a special box that has a dehumidifier so that they can dry out from the wax that might be wet in my ear.

Yeah. Hearing aids can't go into the water. So when I take a bath or do anything that risks my hearing aids getting wet, I have to take them out. That's OK, though. My hearing without a hearing aid is better than some other peoples', which makes me lucky I can swim in the pool and be able to hear people pretty well. Some other people couldn't.

SUBJECT 6: Ba, ba, ba, ba, ba, ba, ba, ba, ba, brains on.

MOLLY BLOOM: Your hearing aids keep you company pretty much all day, every day, and have since you were very little.

XUAN JUNE: And part of having hearing aids, especially as a kid, is regular checkups.

MOLLY BLOOM: Kids are growing and changing all the time.

XUAN JUNE: The hearing aids that I wore when I was five would definitely not fit me now.

MOLLY BLOOM: So Xuan June and her mom, Hong Ann, invited me to tag along for Xuan June's most recent appointment.

DR. DOYLE: Hi, everybody. Come on back.

SUBJECT 7: How are you?

DR. DOYLE: Good. How are you?

SUBJECT 7: Good.

MOLLY BLOOM: That's pediatric audiologist Dr. Danielle Doyle.

XUAN JUNE: She specializes in helping kids with hearing loss.

DR. DOYLE: So just start by telling us how things have been going with your ears and your hearing lately.

XUAN JUNE: Pretty good. I had like an ear canal infection.

DR. DOYLE: I heard that you had an infection. It was pretty painful, wasn't it? Is it getting better now?

XUAN JUNE: Yeah. It's all close.


XUAN JUNE: I didn't wear my hearing aids after that because I think it's too small. Because I think the reason I got it was because I kept moving it around and then scratching it.

DR. DOYLE: So it was itching and you were scratching it. So it might be time for some new ear molds, it sounds like. OK. OK.

MOLLY BLOOM: So Xuan June, tell us again, what is the ear mold?

XUAN JUNE: An ear mold is a piece of like rubbery plastic that is shaped exactly like the shape of my ear that helps the sound get into my ear.

MOLLY BLOOM: So that has to fit just right for the hearing aid to work well. But before you could get a new ear mold, you got your hearing tested.

DR. DOYLE: So the plan for today is we'll look in your ears and see how they look. And then we'll do our pressure test over there called tympanometry, and that lets us see that your eardrums are healthy and moving. And then we will put your earphones in your ears and have you listen for all those different beeps and sounds, OK? Does that sound good, and you'll let us know when you hear them even if they're really soft? And we may-- if we're still feeling good about everything, we might have you repeat some words back for us, too.


DR. DOYLE: OK. Does that sound like a good plan? All right. Go ahead.

MOLLY BLOOM: So they put in your ears these special medical earbuds that you said were squishy like marshmallows and they played a bunch of sounds for you. And you got to whack a big button on the table whenever you heard one.


XUAN JUNE: Next comes the part where they say words to me and I repeat them.

Playground. Baseball. Airplane. Ice cream.


XUAN JUNE: Outside. Sidewalk. Busted.

DR. DOYLE: Some of those words are words that can sound very similar to each other or words that sound similar to other words, so it might just be one letter. If you're one letter off, you could have a completely different word. And so it's just testing to make sure that the listener can hear all of those different sounds very clearly at a comfortably loud level.

But did you hear how we were switching up the different pitches? We went from lower pitches to higher pitches and then also softer and louder sounds, too.


DR. DOYLE: There's also some static noise sometimes, too. Just to make it a little bit more interesting.

MOLLY BLOOM: So now that you're 8 and 1/2, you just listen to sounds and push a button. But when you were getting these tests as a toddler, you weren't able to do that. So you can't remember exactly what that test was like because you were so young. So Dr. Doyle did describe it for us. Here's what she said.

DR. DOYLE: Well, when they're very little babies before they have any developmental head and neck control, we actually do a test where they're asleep.

MOLLY BLOOM: They put tiny sensors on the baby's head that lets them see how the baby's brain responds or doesn't respond to certain sounds.

DR. DOYLE: So it's just a way to get a hearing test on any one of any age, really, who isn't able to do the games in the booth. When they're babies and they can actually turn and look at the sounds, we have them turn to a sound that we're playing from that speaker you just saw. And then when they turn and look toward the sound, they're actually rewarded by seeing those little boxes in the rooms with animals that light up. It's like a reward.

So every time they hear it and they turn, they get to see something fun. But now we have to do it just to listen and press the button.

SUBJECT 1: Going to play the big kid way.

MOLLY BLOOM: The big kid way.

SUBJECT 1: How do you feel about the big kid boring way?

MOLLY BLOOM: You're so good at it now. Yeah.

So your hearing aids are really important for helping you hear certain sounds. But starting when you were a baby, you also worked a lot with a special teacher. I know you can't remember way back then so well, so your mom and dad described it for us.

HUNG ANNE: She got assigned like a social worker/teacher of the deaf from the time she was four months. So Renee, our amazing Renee, worked with her from age four months to three years old once a week coming to our house and doing all kinds of activities. We would have to do these drills with her like with the S-- I don't remember. The-- I can't believe I can't remember now because it was so--

SUBJECT 2: The ling sounds.

HUNG ANNE: The ling sounds, that's it. These are the sounds that are basically the hardest for the human ear to hear in speech. Exactly. Exactly.

MOLLY BLOOM: So Xuan June, can you tell us what these ling sounds are?

XUAN JUNE: Yep. The sounds are a-, u-, e- m-, sh-, and s-.

MOLLY BLOOM: Excellent. So when we're babies, our brains are soaking up so much information. So it's really important to start working on these sounds as soon as possible.

HUNG ANNE: Well, and that's the importance of the early intervention. Because basically she's never missed-- all of the brain connections to connect the sound to what it means is all there. You know.

MOLLY BLOOM: So if they'd waited, she might have missed the S.


MOLLY BLOOM: It would be really hard for her.

HUNG ANNE: Exactly. And you would hear that in how she speaks. Exactly.

SUBJECT 2: Yeah. I would drop out, because she never heard it.

HUNG ANNE: Yeah, exactly.

SUBJECT 2: Whereas now, even without the hearing aids, even if she-- and I noticed this. When she doesn't have the hearing aids in, there's still some words that she'll confuse, right, if I don't clearly say it. Or I slur the sounds. But also from reading about people with deafness describing their own experiences, they talk about how then once they know what it's supposed to sound like, their brain fills it in.

So even if her ears don't pick it up fully, then even without the hearing aids, her brain will just slot in the missing sound and be like, that's a plural based on context.

MOLLY BLOOM: So Xuan June, do you still work with a special teacher like that, or is that just when you were first learning to talk?

XUAN JUNE: Well, I still do. But not the same way. It's at school. I have a special teacher, a teacher of the deaf, that helps me with hearing aids. Now we're working on learning sign language.

MOLLY BLOOM: That's very cool. So Xuan June, I called Dr. Doyle to ask her a few more questions after our appointment. And did you know that she also has hearing loss and wears hearing aids?

XUAN JUNE: No. I didn't know that.

MOLLY BLOOM: Yeah. So she has worn hearing aids since kindergarten. Still does. And we asked her what it was like for her when she started wearing hearing aids.

DR. DOYLE: So my hearing loss was actually not identified until I didn't pass hearing screening at my pediatrician's office right before going into kindergarten.

MOLLY BLOOM: So you can't remember a time without your hearing aids. But Dr. Doyle didn't get them until she was a little bit older.

DR. DOYLE: Life changing. I don't remember anyone ever being unkind to me because of my hearing aids or my hearing loss. I think that I probably imagined that people noticed a lot more than they did. Because when you're a kid, you don't necessarily want to have something different that stands out to people.

And so I think I projected some of that on myself and maybe closed myself off a little bit because of it. And then I think once there was a little bit more maturity and self-awareness, I realized that not wearing the hearing aids was actually impacting me socially more than wearing them, because I was missing inside jokes and I was missing things that people were saying to me, and that was actually impacting my relationships more than just answering a simple question about why I do wear hearing aids would have been.

MOLLY BLOOM: So are there any kids in your class now at school that have hearing aids?


MOLLY BLOOM: What does that feel like, to be the only one in your class with hearing aids?

XUAN JUNE: Well, it would be nice to have some other hearing aid wearers in my class or in my school, but I don't really d because I feel confident in my difference and I feel supported by my teachers and friends.

MOLLY BLOOM: That is really great. If there are kids who feel shy about having a difference, whether it be hearing aids or something else, do you have any advice for them about how to maybe feel more confident?

XUAN JUNE: I'd say just don't really stress it a lot. It's not really going to change about you, and you should be proud of it. It makes you part of a community that a lot of other people aren't part of.

MOLLY BLOOM: That's really good advice. Yeah, it's like everyone has differences in some way, even if you can't see them as readily. So there's nothing to be shy about. Dr. Doyle says that hearing aids have improved a lot since she was young. They used to just take in every sound around a person and make everything louder. So that could be tough in crowded places like restaurants, because it would feel really noisy.

But now, hearing aids have special computer chips inside them that allow them to be totally customized for each person.

XUAN JUNE: Yeah. My hearing aids take the sounds that are tough for me to hear and boost those specific frequencies.

MOLLY BLOOM: So using your test results, we were actually able to make a simulation of what it sounds like for you when you're not wearing your hearing aids. This is the sentence we used. It's the same sentence used to test your hearing aids. It's special, because it contains every sound in the English language. So here's what the sentence sounds like when you're wearing your hearing aids.

INTERVIEWER: A carrot is a long, reddish-yellow vegetable which has several thin leaves on a long stem and which belongs to the parsley family. Carrots are grown all over the world in gardens and in the wild in the fields.

MOLLY BLOOM: And here's what it would sound like without your hearing aids in a noisy room.


INTERVIEWER: A flute is a long, reddish-yellow vegetable which has several thin leaves on a long stem and which belongs to the parsley family. Carrots are grown all over the world in gardens and in the wild in the fields.

MOLLY BLOOM: And here's what it would sound like without your hearing aids in a quiet room.

INTERVIEWER: A carrot is a long, reddish-yellow vegetable which has several thin leaves on a long stem and which belongs to the parsley family. Carrots are grown all over the world in gardens and in the wild in the fields.

MOLLY BLOOM: It's cool to be able to hear just how powerful those hearing aids are and how they're adjusted just for you. Dr. Doyle also measured how air moves through your ear and was able to make adjustments based on the shape of your ear canal, too.

XUAN JUNE: And my hearing aids also have Bluetooth so I can get TV shows or games or even the voice of my teacher piped right into my ears.

MOLLY BLOOM: After the hearing aids were all set, it was time for the most fun part--

XUAN JUNE: Getting new ear molds.

MOLLY BLOOM: The ear molds have to fit in your ear just right so that they're comfortable and we don't get that feedback, and we make sure the sounds are going to the right spot in your ears.

DR. DOYLE: I'm just looking in your ear with my light first, OK? All right.

And this is my cotton block that I'm going to put it in your ear. It protects your eardrum. You don't want any of this pink goopy stuff on your eardrum. This is just a light so I can see where I'm pushing in, OK? Just wiggling it in your ear a little bit.

So I'm going to make my two materials together. The pink and the white, mix it together. And it actually starts a chemical reaction that makes it start to harden. That's how it hardens and dries in your ears. So when we pull it out, it keeps it shape. And we can send that to the ear mold company to make the colors that you want. That sound good? Mushing it all around.

XUAN JUNE: The squishy stuff.

MOLLY BLOOM: Does it have a technical name? Besides the squishy stuff, or--

DR. DOYLE: Does it have a technical name? I know. We call it squishy stuff all day long.

MOLLY BLOOM: Pink mashed potatoes?

DR. DOYLE: It's silicone. Yep.

XUAN JUNE: Can I feel it?

DR. DOYLE: You want to feel it? Yeah. All right. You have to work quickly, because it starts to dry up on us and then it gets really hard to push out of this syringe when it gets dry.

XUAN JUNE: Go, go, go, go, go.

DR. DOYLE: Go, go, go, go, go. All right. You ready? OK, sit nice and still for me. What does it feel like when it goes in there? I think it feels like cold mashed potatoes. You would never want those in your ear, but that's what I think it feels like.

XUAN JUNE: It feels like slime in your ear. Except Play-Doh in your ear.

DR. DOYLE: Play-Doh, yeah.

XUAN JUNE: Really soft Play-Doh. Sort of feels good. It's like a massage.

MOLLY BLOOM: So since I last saw you, Xuan June, you now have shiny new hearing aids. Can you describe them for me, please?

XUAN JUNE: My hearing aid molds have a swirly mix of pink, white, and black. Goth cutie.

MOLLY BLOOM: That's-- goth cutie, I love it. So yeah, so you got to pick new colors. We picked the pink, white, and black because of your goth cute aesthetic. Your ear molds used to be more of a solid chunk that you put in your ear. But now it's almost like a scaffolding that fits in your ear and there's like-- air can move through. And that's because you're bigger now, right? Because those are more for older kids.

XUAN JUNE: Yeah, because I probably wouldn't have been able to get them when I was younger, because I would have been able to just take it right out. And actually that did happen once in the airport. I lost one of my hearing aids. But--

MOLLY BLOOM: Oh, no. I'm impressed this only happened once. That's really great. What is your favorite thing about your hearing aids?

XUAN JUNE: I think my favorite thing about my hearing aids is they're like a superpower.

MOLLY BLOOM: And what do you want kids who listen to today's episode to remember or learn?

XUAN JUNE: I want people to learn and know more about hearing aids and how they work and just what they even are. I feel like they are so rare and have such great technology out. I don't want the knowledge to be lost or hidden.


My hearing aids pick up the frequencies that are tough for me to hear and make them louder.

MOLLY BLOOM: Hearing aids today are customized for each person wearing them. And they even have Bluetooth so people can hear all different types of sounds right in their ears, like the dialogue in a movie or their teacher speaking.

XUAN JUNE: Sounds are made by vibrating air molecules.

MOLLY BLOOM: The vibration travels from the source of the sound all the way to our eardrums, sometimes going through a hearing aid first. That's it for this episode of Brains On.

XUAN JUNE: This episode was produced by Molly Bloom, Rosie DuPont, Anna Goldfield, Nico Gonzalez Wisler, and Marc Sanchez.

MOLLY BLOOM: This episode was sound designed by Rachel Breeze and engineered by Josh Savage Joe and Al Wudarsky. Our editors are Shahla Farzan and Sanden Totten. And our executive producer is Beth Perlman. The executives in charge of APM Studios are Chandra Kavati, Jo Ann Griffith, and Alex Shaffert. Special thanks to Hung Anne June, Duane Dixon, Danielle Doyle, and Matt Wynn.

XUAN JUNE: Brains On in the nonprofit public radio program.

MOLLY BLOOM: If you like the show, head to brainson.org. While you're there, you can tell your friends about us.

XUAN JUNE: Send in your drawings.

MOLLY BLOOM: Donate or subscribe to our smarty pass.

XUAN JUNE: Ad-free episodes just for you.

MOLLY BLOOM: Head to brainson.org. Now let's go back to that mystery sound again.


What new thoughts do we have?

XUAN JUNE: I don't know, but I also just thought of a pond with fish swimming in it, too. So I don't know.

MOLLY BLOOM: So you're definitely sure there's water. We know that much.

XUAN JUNE: Yeah, I think.

MOLLY BLOOM: OK. You ready for the answer?


MOLLY BLOOM: OK, here it is.

COLIN: Hi. My name is Colin, and I'm from Hamilton, Ontario. And that was the sound of me paddling in my canoe.

MOLLY BLOOM: So you were totally right. There was water in a pond. OK? Except it was in a canoe with a paddle. I think you heard that sound when you were talking about the thingy wingy or the stopper was the paddling. Good work. That's not an easy one.


Now it's time for the Brains Honor Roll. These are the incredible kids who keep this show going with their questions, ideas, mystery sounds, drawings, and high fives.


We'll be back next week with more answers to your questions.

XUAN JUNE: Thanks for listening.

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