The noise that isn't there

Every Thursday, three leading tech journalists explore how tech is re-wiring your week and your world. Listen to The Interface on BBC.com or wherever you get your podcasts. From dark matter and black holes to what dinosaurs may have sounded like. And last year, host, Nome Hassanfeld did a five-part series about the way our brains process sound. It's called the sound barrier.

And their second episode is about tenidus.

That's when you perceive or ringing in your ear, this persistent sound that comes from nowhere, almost 15% of adults suffer from us, and there is no cure. In fact, researchers are only just beginning to understand the cause. Here's that piece. And you can check out the rest of the sound barrier series on the unexplainable podcast feed.

Enjoy. I noticed it around just New Year's time.

“I just remember there was something on the bright side of my ear going on.”

It's like, and I thought it was just the pipes. I kept asking my fiance if he's been hearing something going on in the walls next to me. But he's recorded back, nothing. Kelly started hearing things almost four years ago. Just a couple months after her 25th birthday.

At first, she wasn't sure what was going on.

She did the webcam D thing. She Googled all her symptoms. She got worried when she told her family they told her to relax. But the sound didn't stop. I'm pretty soon she started hearing something in her other ear. It's like the high pitch ringing you usually hear in your ear every now and then,

but it's like more intense and it's just their whole time. Wow, so different sounds right in left ear. Yeah. Eventually Kelly decided she needed to get her hearing checked. They've done so many tests on me and I don't have anything wrong with my hearing.

Almost 15% of all adults have had tenidus and a hundred million of them have severe tenidus.

Like Kelly, they hear persistent noises ringing, buzzing, sirens, even construction or drilling sounds, which seriously impact their life. But when a lot of them get their hearing checked, the test comes back fine. It's one of the things that makes tenidus so maddening.

“Why would so many people keep hearing noises like these if the test says there's nothing wrong with them?”

And it's not like most of the people Kelly was talking to or any more help. They didn't take her seriously because they had no idea what living with tenidus actually feels like. I mean, it's like you're just trapped in a room with a crying kid. You can't stop crying or anything. You don't know how to just make it stop.

It's like no way to escape it. Yeah, that's right. Kelly's tenidus got worse and louder environments so she had to leave her job. She stopped seeing her friends, she couldn't sleep. I would isolate myself and everything.

I've grown so distant from my friends because with the lack of sleep, you're just not in any other mood for anybody and you can't show up. Like you used to for any of the things that you've done. The thing that makes tenidus so hard to pin down is that it isn't a sound out there in the world. It is literally just in your head, but it's also real, especially for people like Kelly.

I know I'm hasn't felt and this is the second episode of the sound barrier. A series from unexplainable about the limits of hearing and the ways we can break through.

“On today's episode, how can our brain make us hear sounds that don't exist?”

[Music] Okay, before you go into this, just a question, how do you pronounce this word? Tenidus. So you've got two ways of saying, "Tinidus is, I believe, the proper way of saying it, most people say

A couple weeks ago, I met Stefan Maison at Mass Eye in here, a hospital in Boston.

Stefan's the director of the Tenidus Clinic there, which he launched last year. The vast, vast, vast, vast majority of the patients are being told, "This topic I can do for you, goodbye." I've seen some patients who are like borderline suicidal. And so I was interested in being able to provide some beginning of an answer to those patients and to provide support to those patients.

“And that's why we opened the Tenidus Clinic.”

It was also a way to potentially help his own hearing. I have to, please, you know what is it, Sam? Hi, Pitch. It was in one. I've seen shoes for the past like 12 years, something like that. I haven't been in a club in many, many years, or even decades,

but I can tell you that I abused my ears. So do you hear a Pitch right now? Yep. You probably also had at least a brief moment of Tenidus before. Some people will go to your concerts. They feel that as a leave the concert,

the hearing is not quite the same. You feel that your hearing is a little bit muffled. You can even experience that's ringing in your ears.

Basically, your hearing gets damaged, which means one part of your brain is getting less auditory

information than it expects.

“So another part starts to overcompensate.”

You no longer receive some information in one particular area. The address and the area is going to start to become hyperactive. It's kind of like a climate control system. You have it set to 70 degrees or something. And if it gets too cold, the heat will kick on.

So when the brain suddenly isn't getting the same level of sound, it's expecting from the outside world, it turns up the volume in your head. So now you start to perceive those sounds that he's not there. Usually, this kind of post-concert ringing sound goes away.

But chronic tenidus is when that ringing doesn't stop.

Stuff untold me, it's sort of like Phantom Lim pain in people who've lost a leg. The leg is gone, but it's tough to feel pain where it's missing. Your brain is artificially increasing the perception. So in the case of touch, if you touch you with my finger, like this, you're going to feel my finger. If I increase the perception, that's going to turn into pain.

Sometimes people with tenidus can pinpoint what caused it. I spoke to one researcher who told me his tenidus was caused by sitting too close to a bagpipe band at his friend's wedding. But often tenidus seems like it comes out of nowhere. Like with Kelly, people just wake up one day and hear this Phantom ringing. And just like Kelly did, a lot of them go get a hearing test.

And it often tells them they're hearing is fine. So what's going on? If tenidus, the result of the hyperactivity of the brain, because something is missing, then people with normal hearing test should not have tenidus. So let's talk about that hearing test.

The kind that tenidus patients like Kelly get all the time. You sit in a soundproof booth, you put on headphones. The audiologist plays you a pure tone and they say, "Rose your hand when you pick and hear beep." The audiologist keeps playing the same sound softer and softer until you stop raising your hand. And then they do the same thing for a whole bunch of different pitches.

This is the gold standard for hearing tests. But the hearing test does not tell you the whole story. Our ears can do so much more than just listen to beeps. There's something elected to tell my vision.

“If everything is fine, you should be able to hear a pin drop.”

Or you should be able to hear an explosion. If you think about it, that's a gigantic dynamic range. Our ears can do this because they have different types of auditory nerve fibers. These wires that carry sound signals from the inner ear to the brain. Some of them pick up soft sounds and other ones pick up loud sounds.

But the hearing evaluation only tests for soft sounds. And if the fibers that respond to loud sounds are missing, this is not going to affect whatsoever your hearing test. So the gold standard of hearing evaluation around the world to this day is completely insensitive to the loss of those fibers.

This is how someone like Kelly can have hearing problems. While still having a perfectly normal hearing test, it's called hidden hearing loss. And it was only discovered a few years ago. When researchers at mass ionier realize just how easy it was to damage those loud or nerve fibers.

are the fibers that could for loud sounds.

“The idea is that if you have tenidus at some point in the past,”

you probably damage your hearing. Specifically, you damage those louder fibers. But your symptoms might have gone away, and because normal hearing tests don't focus on loud fibers, that damage stayed hidden. And if your loud fibers get damaged, you're not going to have any issues

having a conversation in a quiet room. You're not going to have any issues on your hearing test. But if you go somewhere like a bar or a restaurant, you might find that you suddenly can't make out what your friend is saying.

And if you look at most people, that's something very, very common.

They feel like they don't have any issues in a quiet environment, but as soon as you go to a bar or a restaurant, they start to struggle.

“So Stefan took his patients with normal hearing test scores,”

and instead of giving them that classic hearing test again, he gave them a different one, focused on loud fibers. Instead of testing them in quiet, it says he's someone who's speaking super fast, with a little bit of reverberation. Like he suspected,

a lot of them really struggled with the louder echoey conversations, because they had hidden hearing loss. They had damage to their loud fibers. And Stefan had a feeling that hidden hearing loss could be the thing causing his patients that had normal hearing test scores to have tenidus. So we ran a different test.

He placed tiny electrodes inside their ear canals, and he played them a sound. A click? He recorded the electrical responses from that sound, and that's going to show you different types of waveforms. It's basically a squiggly line that shows neurons firing as a sound signal

gets processed by the brain. And when he looked at the early peaks, which showed the auditory nerve in the inner ear, he saw way less firing than normal. The patients were getting less sound input, because they had hidden hearing loss. But then he looked at the later peaks on the squiggle. The ones that showed what happened as the sound signal winds its way into the brain.

So now you're looking at the brain stem response,

and interestingly, the participants with tintus had response as big as those who never had tintus.

For tenidus patients, the peak at the brain stem was larger than at the nerve. Something was making up for the hidden hearing loss and turning the volume up. Somehow, the brain was able to catch up. Stefan was basically seeing the seeds of tinnitus on this squiggle graph. This thing that didn't show up in normal hearing tests.

This thing that so many patients had been told wasn't real. He saw it happening. Tintus is not a sound in your ears. Tintus is a gerity that the central nervous system. The idea that hidden hearing loss is directly related to tinnitus. It's a big step forward, but there's still so much we don't know.

Like, we know the basics that tinnitus usually starts with hearing loss, which can be caused by things like listening to loud music, or a virus, or aging, but not everyone with hearing loss. Here's this constant ringing. Scientists still don't really understand what takes someone from hearing damage to tinnitus. Why this happens for some people and not others?

“Had I not told you, but what you must take from madness?”

Once you got diagnosed with tinnitus, Kelly started doing all kinds of research online. She was trying to find anything that could help her feel better. I found this YouTuber who makes these like white noises, or he calls them pink noise, brown noises, there's so many different ones. This is the 15 kilohertz tinnitus, audio, noise, masquer, right around 15,000 hertz.

This kind of thing is called a masquer, because it masks the sound of tinnitus. And Kelly eventually went to her audiologist to get hearing aids that played these sounds for all the time. But because the hearing aids also amplify sounds, she had to wear ear muffs over them too, which isn't great when you're in your 20s and just trying to go outside. So all in all, it's been helpful, but it's far from perfect. And Stefan isn't really a huge fan

of stuff like this to begin with. It's just a bandits. I don't think it's very useful. Stefan says that even though a masquer is designed to blend the tinnitus noise in with the background, it ends up becoming the majority of what people are actually hearing.

tinnitus. And the more you think about tinnitus, the worse it can get.

“We're talking about this right now, so I can hear it's much louder thanks to you.”

I'm sorry. But I know it's because I'm thinking attention to it. For some people with mild tinnitus, a bandaid like this can be useful from time to time. But for people like Kelly with severe tinnitus, it's a lot more complicated. I wanted to be able to go back to Kelly with some useful information, but I wasn't really sure what I was going to be able to tell her until I talked to Dan Polly.

I have tinnitus, and whenever I want to, I can hear that beautiful symphony of that pure tone. Dan's a tinnitus researcher who also has tinnitus, like Stefan, and apparently a whole bunch of tinnitus researchers, as I found out, Dan also works at mass iron here, and he focuses on how

“different parts of the brain work together to generate the tinnitus sound.”

Because the brain doesn't have direct contact with the physical world, everything that we perceive as consciousness is constructed from the activity of the brain. Dan told me there's a pretty fundamental difference between the mild tinnitus he has, and the severe tinnitus that people like Kelly have. People truly severe tinnitus have like a whole brain problem. Their tinnitus has expanded, and it's incorporated like other brain networks.

And whatever hyperactivity in my auditory pathway that's causing me to perceive a sound that isn't there, it hasn't changed the ability of my executive control to concentrate, or it has a re-programmed my limbic system to find all sounds horribly aversive and make me depressed. You're saying when some people are obsessed and can't function because their tinnitus, it's not because they just hate the sound. It's because that sound has gotten into their

brain system and what infected their brain. Yeah, it isn't actually that their tinnitus is louder, that hyperactivity is spilled over and recruited other brain systems that have nothing to do with hearing per se, but with your ability to concentrate, to sleep, to regulate mood and emotion. They have a more widespread network of dysregulation in their brain than I do. For people with severe tinnitus, Dan says things like mindfulness therapy, or cognitive behavioral

therapy can act on these other brain areas, and hopefully tamp down the tinnitus. They can take you from like, I have tinnitus disorder, I'm not sleeping, I'm depressed, I'm socially withdrawn, and they can turn you into somebody like me. It's like a little bit annoying, but if you can take the one in ten who's severely debilitated by the tinnitus and turn them into like the other and I, I'd still take that as a something useful. Yeah, so it's been almost a year since

“we talked. How are you doing? I've been doing a lot better, I would say honestly like, I've been”

happy. I guess I've just been trying to be more open about it because I realized that I never

shared it to anyone at my job. Now, I'm just like trying to just put myself out there again. It just closes you in this insane box, you know, you have nowhere to go, and you just somehow find a way to chisel through it. And you feel like you're slowly chiseling through it? Chisel again, still making my way out. I told Kelly what Dan had said about people with severe tinnitus. I would not like they're just being weak that they might have a whole brain problem that their tinnitus has basically

expanded across their brain networks and hooked into the parts of their brain that influence other things like their emotions. That's, I feel like that just feels like a better explanation

because I've always had a hard time describing it, but it kind of makes me feel a little

at ease again where I'm like, okay, maybe it's still not entirely like me, me, like, you know. It's going to be a long process, but Kelly told me she's been trying to slowly phase out her maskers and her hearing aids and she's trying to learn how to listen to the world again. I'm actually just spending days in my apartment only just without my hearing aids and just trying to take in all the sounds like I'll have the windows open because the maintenance guys are

working or the gardeners and I'm even trying to like vacuum with all any type of like a hearing protection and just recognizing that sounds too. She still hears that tinnitus sound all the time,

all the other sounds along with it. I mean, we saw fireworks show for the first time in years and

“it was scary each time when off the eventually my body would stop shifting when they would because I was like,”

this is what we used to do. It's literally just, it's really weird to know the world again.

[Music]

“This episode was reported and produced by me, now I'm Hassan Feld. I also did the music.”

It was edited by Joanna Salataroff, without from Jorge Just, mixing and sound design from Christian

Ayala, with a ringing endorsement from Sally Helm. Meredith Hadenot runs the show.

“Julia Lungoria is our editorial director. Unexplainable is part of the Vox Media podcast network.”

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