Rescue Hearing Inc.

Audion and Acousia.

Well... I kind of pointed out a flaw in this call for participants.

They want people whose main complaint is hearing loss! Not tinnitus!

Well, my main complaint is tinnitus. Hearing loss is treated more like a tangible disease, while tinnitus is just this "mystery" no one understands or wants anything to do with. When I talk to a doctor, he says that tinnitus is a "symptom"... this "mysterious symptom"... well symptom of what exactly? Many things! They say... Well I don't know about others but in my case it's most definitely caused by noise induced hearing loss. But am I an attractive candidate for a "hearing loss" clinical trial? Well no... because my main complaint is tinnitus...

I think I will just sit and wait for a call for a "tinnitus trial"...



....

Do you have hearing loss? While yes! I have tinnitus! Don't even need a hearing test! If you have tinnitus, then you know you have hearing loss! It's a symptom, the most obvious symptom of hearing loss!

 

Yeah, I do have some mild hearing loss in the 4 kHz to 6 kHz region on my left ear. I have expressed my interest in the Regain project. Will see what they say in the coming month.

What's your hearing like? I take it it's not a perfect 0 dB throughout the hearing range, if you worked in such establishments as clubs and pubs?

I had a very sharp 30 dB drop at 6000 Hz on my first ever audiogram. This was done several months after the acoustic trauma. Two months later, I did a new test and it showed 15 dB drop at 6000 Hz. It was around that time I started noticing a tonal tinnitus. Now I can hear twice as good?! So good that I can hear things that are not there.

Several months have passed since the second audiogram. Who knows... maybe if I did a new test now I would get a perfect score. Perfect hearing... or not. The point is, hearing does get better with time, as does tinnitus. Or does it really?...

 

Good find @tomytl !

We are now at 24 companies total according to my count. Some of these companies are more developed than others. But I sure hope to see more companies coming to this field.

 

http://rescuehearing.com/imaging/

I wonder what this is about? Assessing inner ear function with imaging technology? Intracochlear imaging? Does anyone here know what KOL is referring to? This is very interesting. Their genetic tests seem interesting as well.

Where is this company based in?

 

That's interesting! How is your hearing above 8 kHz then? How far into the high frequency range can you hear? I stop hearing at about 13 kHz.

I don't expect mine to get any better just by sitting and waiting for it to get better. I was exposed to a really loud impulse type of noise. It killed off some hair cells right on the spot, I'm sure of it. Tinnitus is more than just the ears of course. I don't have to tell you that the brain plays a crucial part in this. It's a series of events that in almost all cases begins with the ears. Some damages may be small, some may be larger, and it all adds up, and eventually these cells deteriorate to the point that you start having tinnitus.

 

Agreed! Hence my question to Paul above, about his upper limit. Tinnitus might begin to develop right after you lose your 15 kHz to 18 kHz range of the sensors.

So few? I think you meant so many. The typical audiogram is from 250 Hz to 8000 Hz. This is the range that's responsible for speech recognition. As long as you can hear human speech well, they are done with you. Everything above 8000 Hz is redundant.

Oh yes! And the earliest hearing aids could not amplify sounds beyond 8000 Hz. The world standard for audiograms is from the same era.

Historically, the first hearing aids were like big trumpets you hold up to your ear, on either left or the right side. You would hold them with both your hands. If you were rich and strong enough you could have two, one for each ear. Fast forward to audiograms and you find "electronic" hearing aids. Analog!

Meanwhile, hearing aids are now digital. And! They can amplify sounds well beyond 8000 Hz! And! They can now use advanced math and physics to make you hear things you are normally not capable of. For example, if your hearing ends at 6000 Hz, the devices can still pick up everything from 6000 Hz up to 20000 Hz and manipulate the incoming signals so that you can hear it all with your limited cochlea in the range 20 - 6000 Hz. Plus! You can have these hearing aids connect to your smartphone via Bluetooth and you can take phone calls with it. They do all kinds of technical wizardry. I would not be surprised if they can help you find a parking lot, or start a washer machine at home.

So originally, the first specification for the audiogram came along at the same time as analog electronic hearing aids, and those were limited to about 8000 Hz. And yes, normal human speech is also within that range.

But if you would like to try out a hearing aid, they can have you do an advanced test where they test your hearing higher than 8000 Hz. So that they can fine tune them for your ears. And yes, all clinical audiometers can go much higher than 8000 Hz. Most cheaper models can do it as well. Plus! They can adjust the frequency intervals down to a single cycle (1 Hz). I think those features are reserved for research only... Up to 8000 Hz is good enough, so why bother!

 

I may have jumped to conclusion. I know I read some article about this several months ago now. It discussed the different technical aspects of hearing aids, such as what frequencies they can amplify and how they can compress frequencies. They may not be able to amplify beyond 10000 Hz. But they can compress them and make these high frequencies audible to the ear.

Presbycusis, yes.

I was thinking about progressive loss as part of the aging process, and how that may or may not lead to tinnitus. But here is what I struggle with! How do you tell apart hearing decline caused by natural degeneration from that caused by acoustic trauma? Insult to the ears doesn't have to be a significant one time event. It can be the result of a number of small insults that all add up to a large total.

How do you know what that average is?

When I go out looking for the hearing loss curves that correlate to age groups, I find something like this:


Frequency stops at 8 kHz!



Frequency stops at 8 kHz!



Frequency stops at 8 kHz!


This graph tries to push it to 16 kHz, but data points are missing to cover the entire range. I am not surprised that it's missing, there are not too many sources for researchers to pull that data from. The majority of all audiograms ever done in the world only go as far as 8 kHz. That has been the standard for a long time now, and it still is.

The high end of the frequency range in this graph appears to have been manually filled in with a pencil, not plotted by a machine or a computer program.

No one cares for the far end of the hearing range. Scientists just tested it some ages ago and found that we can hear up to 20000 Hz and they said OK, that's that, they recorded the fact and never looked back at it.

We may not learn something significant related to tinnitus by studying these far ends of the hearing spectrum. But it's just so simple to do these days! Why would we not test it? Where is the interest? Where is the curiosity? If nothing else, it can serve as an early warning system for when our hearing is deteriorating too quickly. "Professionals" don't care about it until our hearing is already too deteriorated and we are fit for hearing aids.

 

All things that scientists cannot explain is part of the aging process!

What is age anyway? It's just a number!

 

Studying the high end of the hearing range may be useful in following ways:

1. Detect early onset of hearing loss.
2. Provide early data collection about hearing loss in diverse populations.
3. Offer an opportunity to visually study hair cell death, in-vivo.