Brain's 'Amplifier' Compensates for Lost Inner Ear Function

[Reinier]

Above the knob it reads "volume 11"
So it should be set at 11 ?

 

[Nick Pyzik]

I would be interested in reading about this. Could you give a link?

I've been posting this article quite a bit because it really makes sense and relates to how my hearing is now and I'm not even an old chap yet. I think that noise just speeds up this process of age-related hearing loss which is what is talked about with the nerves in the article. It's the brain trying to compensate for the lost incoming nerve connections and so it sends out its own nerves so that the person can still try and hear correctly like before but ends up making things harder for one to hear. Plus I don't believe these new nerves have neurotransmitting functions like the original incoming nerves which I believe are called Afferent nerves or Efferent, I still don't know which one acts as the neurotransmitter in the inner ear. All I have to say is if these new nerves had the same functions as the original nerves to which you were getting neurotransmissions from the frequencies you were hearing before, then I would be able to still enjoy music and feel emotions from it but I don't anymore.

http://www.sciencedaily.com/releases/2015/07/150713095145.htm

 

[Nucleo]

I think that noise just speeds up this process of age-related hearing loss which is what is talked about with the nerves in the article.

Age related hearing loss is a bit of a misnomer. Hearing damage is cumulative over all the exposure you have. So yes, over the years you are exposed to more noises but the actual age has nothing to do with it. The hearing system is meant to last a lifetime and the hair cells/neurons do not have an expiration date.

 

[Nucleo]

This article suggests that all t is due to damage of inner and outer hair cells of the inner ear causing hearing loss.
However, t can be caused by so many things, not just noise exposure. Stress alone can cause t. Hormones. The list is endless. Some may say that this can chemically induce hearing loss.

This is not what the article is saying.

The auditory nerve is comprised of thousands of tiny nerve fibers responsible for transmitting sound information to and from the ear and the brain. Recent discoveries have shown that they are the most vulnerable structures in the inner ear, and they naturally die away throughout the human lifespan due to exposure to noise, medications and even simply aging.
​

Hair cells are not the same as nerve fibers. In fact, I dare say exactly the opposite. Tinnitus is caused by damage to those nerve fibers, not hair cells. It just so happens that if you have hearing loss which indicates damage to the mechanical components of the inner ear, those nerve fibers are very likely to be damaged as well.

Then there is also plenty of cases where no hearing loss is found and yet bad T and/or H happens. This article explains it.

 

[Nick Pyzik]

This is not what the article is saying.

The auditory nerve is comprised of thousands of tiny nerve fibers responsible for transmitting sound information to and from the ear and the brain. Recent discoveries have shown that they are the most vulnerable structures in the inner ear, and they naturally die away throughout the human lifespan due to exposure to noise, medications and even simply aging.
​

Hair cells are not the same as nerve fibers. In fact, I dare say exactly the opposite. Tinnitus is caused by damage to those nerve fibers, not hair cells. It just so happens that if you have hearing loss which indicates damage to the mechanical components of the inner ear, those nerve fibers are very likely to be damaged as well.

Then there is also plenty of cases where no hearing loss is found and yet bad T and/or H happens. This article explains it.

Wow Nucleo, thank you for actually understanding the mechanisms involved in age-related hearing loss and how damage to the auditory nerve fibers can result in tinnitus and are much more susceptible to damage. I basically proclaim these things in all my posts! I'm sure you've seen them.

I would also like to add that with this new auditory nerve hearing loss issue, these new nerve fibers that grow out don't function the same as the original. They don't allow the person to hear as well and they don't have neurotransmitting abilities like most of the previous neurons had. The worst part of all is that these new nerves can make it seem like you still have a well working auditory nerve and that theres no problem at all. I took an Auditory Brain Response test about a month and a half ago and it came back as negative, but yet I can't even hear music playing from an in-ear headphone with noises going on around me plus I don't feel any emotion/enjoyment from it. Which is not from being in a depression. I just literally can't no matter how hard I try.

I'm really hoping that one day we'll have a treatment to fix this issue by being able to transplant neurons into ones inner ear allowing the correct neurons to form again and in replace of these faulty nerves that take over. I'm not sure how we'll be taking care of these faulty nerves that grow and connect to hair cells.

Any idea @Nucleo ?

 

[Zorro!]

This is not what the article is saying.

The auditory nerve is comprised of thousands of tiny nerve fibers responsible for transmitting sound information to and from the ear and the brain. Recent discoveries have shown that they are the most vulnerable structures in the inner ear, and they naturally die away throughout the human lifespan due to exposure to noise, medications and even simply aging.
​

Hair cells are not the same as nerve fibers. In fact, I dare say exactly the opposite. Tinnitus is caused by damage to those nerve fibers, not hair cells. It just so happens that if you have hearing loss which indicates damage to the mechanical components of the inner ear, those nerve fibers are very likely to be damaged as well.

Then there is also plenty of cases where no hearing loss is found and yet bad T and/or H happens. This article explains it.

You and Nick explain this stuff better than any doctor I've seen yet. It's like they don't even know about nerves. They just mutter the standard line about hair cells then dismiss the patient without giving any other information than that.

There really needs to be more research into the auditory nerve and nerve fibers.

 

[Nucleo]

I took an Auditory Brain Response test about a month and a half ago and it came back as negative, but yet I can't even hear music playing from an in-ear headphone with noises going on around me plus I don't feel any emotion/enjoyment from it. Which is not from being in a depression. I just literally can't no matter how hard I try.

I'm experiencing the same. Back then (pre-T days) I would get chills from listening to music. I never do anymore. I guess I've habituated to music as I did for T.

I'm really hoping that one day we'll have a treatment to fix this issue by being able to transplant neurons into ones inner ear allowing the correct neurons to form again and in replace of these faulty nerves that take over. I'm not sure how we'll be taking care of these faulty nerves that grow and connect to hair cells.

I'm sure neurogenesis is the way to go. However, I think we are pretty far form performing surgery inside the inner ear so transplantation is out of the picture at the moment. The cochlea is very deeply incased in hard bone and very small. Probably why it is still so enigmatic in 2016.

 

[Zorro!]

I'm sure neurogenesis is the way to go. However, I think we are pretty far form performing surgery inside the inner ear so transplantation is out of the picture at the moment. The cochlea is very deeply incased in hard bone and very small. Probably why it is still so enigmatic in 2016.

With advancements in arthroscopic laser surgery I think it will get easier to reach areas like the cochlea in the future. It would only take a pinpoint incision to be able to transplant stem cells probably, no actual cutting with scalpels, etc. Of course I'm not surgeon so that's just a guess on my part. But when I see how advanced and routine arthroscopic procedures have become today it gives me hope that something like this will eventually be available.

 

[lapidus]

Tinnitus is caused by damage to those nerve fibers, not hair cells. It just so happens that if you have hearing loss which indicates damage to the mechanical components of the inner ear, those nerve fibers are very likely to be damaged as well.

Yup, that's what Charles Liberman has been saying for some time now with his talk about "hidden hearing loss".

 

[Nick Pyzik]

Yup, that's what Charles Liberman has been saying for some time now with his talk about "hidden hearing loss".

Has he been up to anything lately?

 

[liquefact]

Tinnitus is caused by damage to those nerve fibers, not hair cells.

This is not quite right. Tinnitus can be caused by any of the issues along the pathway from eardrum to auditory system.

For the inner ear part, Sensoryneural hearing loss happens because of either death of sensory cells or nerve cell damage/disconnection from sensory cells. We have approximately 15K sensory (hair) cells in cochlea and acoustic trauma certainly damages these cells. The more damage, the more hearing loss you have and to compensate the loss of signals, brain increases the gain. Same acoustic trauma can disconnect the nerves from sensory cells as well, resulting in again loss of signals, hence T.

Watch the video below, Particularly look to 5:10;
http://www.oricularx.com/#!hearing-loss/cw8q

 

[Nick Pyzik]

This is not quite right. Tinnitus can be caused by any of the issues along the pathway from eardrum to auditory system.

For the inner ear part, Sensoryneural hearing loss happens because of either death of sensory cells or nerve cell damage/disconnection from sensory cells. We have approximately 15K sensory (hair) cells in cochlea and acoustic trauma certainly damages these cells. The more damage, the more hearing loss you have and to compensate the loss of signals, brain increases the gain. Same acoustic trauma can disconnect the nerves from sensory cells as well, resulting in again loss of signals, hence T.

Watch the video below, Particularly look to 5:10;
http://www.oricularx.com/#!hearing-loss/cw8q

Why can I still hear the whole frequency range yet I've had such horrible trouble with my hearing the past 5 months including tinnitus, hyperacusis, speech comprehension, severe depression, cognitive issues, memory issues, loss of enjoyment to music, and exhaustion? I'm sure if I find an antidepressant that's more suitable for me then I'll be able to take some of the heaviness out of my life I feel everyday and it could improve my memory issues but there is something being missed. Why have the multiple audiograms I've taken come out as normal hearing so that everything should be fine. My Otoacoustic Emissions test came out fine so my outer hair cells are fine. I took an auditory brain response test that seems fine although I'm having all these issues. I got an MRI done nothing wrong there. Something is being missed and just by connecting a few of the articles talking about the auditory nerve fibers, you can look at it like a puzzle piece. The brain tries to fix and adapt to the hearing issue taking place and therefore tries to regenerate new nerves. These nerves are not the same functional nerves as before and I have yet to understand why. I mean I'm not a scientist and I'm not hands on with this kind of stuff so it's hard to understand the whole picture. But it goes to show that these tests being done by audiologists/ENT's don't always show up as an answer to your problem. Why did I have an auditory brain response test that said it was functioning fine yet I'm having very difficult issues with my hearing.

I'm sure that there are other causes for tinnitus and losing hair cells can cause it too. But think about it, what's connected to these hair cells too? The auditory nerve fibers. So when the hair cells die you lose the neurons connected to it too. I can't get over it enough that the nerves that connect our hair cells to the brain play a much more sophisticated and important role in our hearing than the hair cells do.

Sure the hair cells are what allows us to hear the frequencies of 20hz-20khz but the nerves that are attached to each specific hair cell region are what give us that ability to enjoy that frequency range (through the healthy synapses that give off neurotransmissions) and even makes that frequency range louder for us to hear working in tangent with the outer hair cells/inner hair cells.

I realized something last night that was pretty interesting to think about and gives a deeper understanding about how important healthy auditory nerves are and how precisely they work with the much needed hair cells themselves. As a once deep lover of music (although I'm still trying my hardest to keep that love going) and music producer I thought to myself how can a producer have such an ear for music and have the ability to equalize and manipulate a sound wave to give another music fanatic the ability to hear that track in the highest producible quality available. This may not be understood by you guys but if you are a producer you should. When a producer is editing the sounds they've recorded they need to eq the tracks so they sound well put together. When you think about it, how does a producer know what sounds best with those frequencies being eqaulized? It doesn't matter at all if they can hear 20hz-20khz because that means they'll just be picking up the normal sound waves that the instruments are creating. The reason why producers can have such an ear for music is because of how WELL they hear those frequencies and that's because of how many of the auditory nerves they have that are working on each hair cell region. The more nerves you have connected to your hair cells, the much clearer and louder you'll be able to pick up the pitch of the sound waves plus the more enjoyable the sounds you hear will be because of the neurotransmissions going on with your healthy auditory nerve and hearing.

 

[Silvio Sabo]

Has he been up to anything lately?

Yes. He and his colleagues have started a company called Decibel Therapeutics. You can check it out here: https://decibeltx.com/

They have managed to secure funding of $52M. So hopefully we will see exciting things coming out from there in the coming years.

 

[Nick Pyzik]

Yes. He and his colleagues have started a company called Decibel Therapeutics. You can check it out here: https://decibeltx.com/

They have managed to secure funding of $52M. So hopefully we will see exciting things coming out from there in the coming years.

Oh yeah! I had looked into that company not to long ago.

 

[liquefact]

My Otoacoustic Emissions test came out fine so my outer hair cells are fine.

Hi Nick. When you loose some hair cells or lose some connection bw nerves and cells, you can still hear fine and your all tests may show that you have perfect hearing. You cannot jump into the conclusion that if these tests show no hearing loss, then i have no hearing loss. (In my case my audiogram is fine but my otoacoustic test show some loss in 6-7Khz region. The tests are not 100 healthy themselves.) Because the hearing system is not 0-1, but can be thought more of an analog system.

There are multiple hair cells for each frequency. You may lose some of them and you'll still hear fine. It'll just be less information sent from cochlea to brain and brain shall compensate for the loss of information. If you keep losing more over time, after some point the amount of info sent from the cochlea will not be basically enough for the brain the interpret the signal and it'll try to recover the lost information by some post processing. This post processing may include the amplification of the whole signal. When this happens, the background noise in the cochlea which people who do not have hearing loss do not hear becomes audible, hence T.

Of course same thing is valid for the disconnected nerves, like any other party on the auditory pathway.

One thing to emphasize is, there are multiple hairs for every frequency and it's believed that all these different hairs are responsible for different intensities in the same frequencies. So if you lose some hairs that are responsible for loud sounds, you'll still hear normally, so it'll not show up in the tests. Also, there are multiple nerve fibers connected to each cilia group. When you loose some of these fibers, you can still transmit some information to brain, but the more fibers you loose, the more information is lost. When these losses reaches to some threshold, brain's post-processing mechanism kicks in and tries to compensate, hence you may have T or you may have some hearing disorders because simply the quality/integrity of the signal brain receives is not enough.

This is my understanding after casually reading stuff about cochlea and how it works. There are multiple serious studies to restore the dead hair cells and make at least some of the functional again, which is the true fix of T, H and hearing loss. I may be 10 years we'll restore our hearing and the associated issues T, H shall diminish.

 

[Reinier]

I took an Auditory Brain Response test about a month and a half ago and it came back as negative, but yet I can't even hear music playing from an in-ear headphone with noises going on around me plus I don't feel any emotion/enjoyment from it.

Hi Nick. What you say here makes me wonder.
This is something that an audiologist can test. I am not talking about the emotional aspect. I wonder if you got this test done. Perhaps they only test this if your audiogram is showing loss of hearing.
The test is quite simple and you probably know the test. Background noise is generated. I forgot what kind of noise. If I remember correctly it was white noise. In the background of this noise words are spoken. The background noise increases all the time or the words spoken go down in volume. Anyway: the person undergoing the test needs to repeat the words as long as he or she is able to understand them. This to me seems to be a reasonable test to assess how accurate your hearing is and at the moment I would not understand how this test is different from distinguishes sounds in real life situations.
Your story made me realise that perhaps this has not been done in your case because there still is an assumption that hearing is accurate when audiogram is not showing hearing loss. I have moderate to severe hearing loss in one ear. So this test was part of the hearing assessment.
Also I wonder if damage in the cochlea is the same for extended overuse or a high level impulse sound (gunshot, explosion etc..).
But that is a different subject completely.

 

[Nick Pyzik]

Hi Nick. What you say here makes me wonder.
This is something that an audiologist can test. I am not talking about the emotional aspect. I wonder if you got this test done. Perhaps they only test this if your audiogram is showing loss of hearing.
The test is quite simple and you probably know the test. Background noise is generated. I forgot what kind of noise. If I remember correctly it was white noise. In the background of this noise words are spoken. The background noise increases all the time or the words spoken go down in volume. Anyway: the person undergoing the test needs to repeat the words as long as he or she is able to understand them. This to me seems to be a reasonable test to assess how accurate your hearing is and at the moment I would not understand how this test is different from distinguishes sounds in real life situations.
Your story made me realise that perhaps this has not been done in your case because there still is an assumption that hearing is accurate when audiogram is not showing hearing loss. I have moderate to severe hearing loss in one ear. So this test was part of the hearing assessment.
Also I wonder if damage in the cochlea is the same for extended overuse or a high level impulse sound (gunshot, explosion etc..).
But that is a different subject completely.

Yes after getting the ABR and DPOAE tests it was mentioned to me to try and set up an appointment for a speech recognition test but really the audiologist said in the end it isn't going to treat the issue or anything. It's just to see how well you can perform in those situations. I may end up getting it down the line but I'm more worried about what can be done to fix my issues and when it could possibly be available. I just did the full audio spectrum 20hz-20khz and I can still hear it all very well. I mean it doesn't seem perfect but I had moderate to severe hearing loss I would be struggling to hear a good portion of it which I don't. The reason many people especially the elderly have trouble picking out words with other noises going on even when wearing hearing aids to help is because of auditory nerve fiber loses. These nerves help you to pick out and process the frequencies they are associated with because they make the sound wave much more louder and clearer in the brains processing center.

There is an article stating that these nerves die out as we get older (age-related hearing loss) and are replaced by a one way nerve that doesn't function like the original and doesn't allow you to hear like you did before. If this article wasn't published then I wouldn't be talking about this stuff all the time. It just makes so much sense. I hate that I keep talking about it in all my posts now but really it shows that people can still have fine functioning hair cells but yet if their auditory nerves aren't working correctly then they'll still have hearing problems. The nerve fiber synapses help the brain pick out sounds from other noises going on. You need nerves to work along with the hair cells for well functioning hearing.

 

[Reinier]

but really the audiologist said in the end it isn't going to treat the issue or anything

Well yes. But why does this test exists? So we only test for hearing loss to find out how we need to adjust a hearing aid. I suppose that is what we are able to do at the moment. Me personally I would like to have an explanation. Perhaps this is a little bit like my ENT told me "you have tinnitus and hyperacusis. No cure. You have to live with it. But don't worry. It is not life threatening". I already knew that that is no cure for hearing loss. I didn't know about T and H

But I understand what you are saying. I read this article you gave a link to earlier.
I still have difficulties getting my head around this whole process of speech recognition versus hearing damage.
When we hear all the frequencies at the correct levels, without distortion, how is it possible we are not able to hear accurately in a noisy environment? With my damaged ear I simply do not hear certain frequencies.
It is not that I don't think this is the case, it is just that most effects I can understand that are supposed to happen when we damage our hearing. Just not yet this process/effect. Even after reading the article. But in time, after reading more documents regarding this process, I will understand I suppose. We can only be patient and wait for science to be able to repair/regenerate damaged cells.

 

[Alue]

There is an article stating that these nerves die out as we get older (age-related hearing loss) and are replaced by a one way nerve that doesn't function like the original and doesn't allow you to hear like you did before. If this article wasn't published then I wouldn't be talking about this stuff all the time. It just makes so much sense. I hate that I keep talking about it in all my posts now but really it shows that people can still have fine functioning hair cells but yet if their auditory nerves aren't working correctly then they'll still have hearing problems. The nerve fiber synapses help the brain pick out sounds from other noises going on. You need nerves to work along with the hair cells for well functioning hearing.

As liquifact was saying there are multiple nerve fibers connected to each cilia group. And there are nerve fibers for high threshold and low threshold in each range (and probably everything between). It makes sense if you lose enough you don't get a complete auditory 'picture' and everything sounds disjointed even if you don't have an easily diagnosable hearing loss.

 

[Nick Pyzik]

Well yes. But why does this test exists? So we only test for hearing loss to find out how we need to adjust a hearing aid. I suppose that is what we are able to do at the moment. Me personally I would like to have an explanation. Perhaps this is a little bit like my ENT told me "you have tinnitus and hyperacusis. No cure. You have to live with it. But don't worry. It is not life threatening". I already knew that that is no cure for hearing loss. I didn't know about T and H

But I understand what you are saying. I read this article you gave a link to earlier.
I still have difficulties getting my head around this whole process of speech recognition versus hearing damage.
When we hear all the frequencies at the correct levels, without distortion, how is it possible we are not able to hear accurately in a noisy environment? With my damaged ear I simply do not hear certain frequencies.
It is not that I don't think this is the case, it is just that most effects I can understand that are supposed to happen when we damage our hearing. Just not yet this process/effect. Even after reading the article. But in time, after reading more documents regarding this process, I will understand I suppose. We can only be patient and wait for science to be able to repair/regenerate damaged cells.

Yeah so Alue was able to answer some of your questions with his post above. All I can say is that when hair cells are damaged it would make much sense that the nerves connected to them would be damaged too and disconnect. Once disconnected, these nerves will retract back into the brain and eventually die which is how some peoples tinnitus' just disappear on its own, or the brain has changed its plasticity enough for them not to hear it until they cover up their ears and focus on it very hard.

The worst part of all and this correlates with @Alue 's post above. Yes we lose these nerve fibers that work with the high and low thresholds of our hearing but once these nerves disconnect and eventually become glial scars or die, new nerves from the adapting brain are sent out and reconnect with the missing areas of the hair cells. Not only are these new nerves much different in function than the original but how are ENT's/Audiologists supposed notice these new patterns of nerves working with the cochlea's hair cells? Researchers just found this out not to many months ago too. I mean the standard audiogram test and the DPOAE don't show auditory nerve fiber damage but the ABR does and how can it be seen that something is different and going wrong inside the inner ear if these new nerves attach and the brain can still pick up sound. It makes it seem like nothings wrong as long as you have the correct amount of nerves connected to hair cells.

I also don't think that the neurotransmitting functions of these original nerves are looked at enough. I mean neurotransmitters are very important for the brain to process emotions and to work well with its cognitive abilities.

 

[Aaron123]

Once disconnected, these nerves will retract back into the brain and eventually die which is how some peoples tinnitus' just disappear on its own, or the brain has changed its plasticity enough for them not to hear it until they cover up their ears and focus on it very hard.

I'm interested in the relationship between nerve death and disappearing tinnitus. Could you please provide a reference or references to support this?

 

[Nick Pyzik]

I'm interested in the relationship between nerve death and disappearing tinnitus. Could you please provide a reference or references to support this?

Yes, a Dr. Liberman talks about this in these two articles. One clearly explaining the dangers of headphone usage (basically loud noises, sound waves, air that can damage the connections of the afferent/efferent nerves associated with each different Outer and Inner hair cell of the cochlea). The second article talks about how although signs may point to the inner ear recovering from noise damage over time, it actually does not and can in fact lose a high number of nerve synapses that produce neurotransmitting pulses, help with our threshold of hearing, and help us pick out and process noises when multiple frequencies are going on.

http://www.nydailynews.com/news/nat...den-hearing-loss-risk-study-article-1.2230945

http://acoustics.org/pressroom/httpdocs/159th/liberman.htm

Liberman clearly states that once the connection has been lost being the nerves and the hair cells from loud noise, they will eventually retract back to the neuron(s) located in the brain and within a matter of time...months to a year, will die. Clearly when people on this site claim they've gotten rid of their tinnitus, it's either A) the neurons have retracted back and have died or B) the neurons have died, there could still possibly be a ringing sound but the brains ability to adapt and change its processing system has caused the patient to not hear it unless they plug their ears and drown out any possible noise and listen very closely.

 

[Nick Pyzik]

I'm interested in the relationship between nerve death and disappearing tinnitus. Could you please provide a reference or references to support this?

Now I can say this again from other posts, I'm not at all sure what causes ringing for sufferers who have not been around loud noises and have taken the steps to understand what could of set it off like medication, toxins, stress.....but I do know 100% out of the many documents, articles, papers online that damage to the nerve fibers of the auditory nerve will causes hyperacusis and tinnitus. Depending on how many of these nerves have been damage will result in how loud you hear this tinnitus or how severe your hyperacusis will be. Now like liberman talks about, when the neurons retract back into the brain and end up dying, what will take the place of these missing nerve fibers that were once connected so perfectly to the hair cells in the cochlea?

Well that's where the article talking about new outgoing nerves comes into play.
http://www.hopkinsmedicine.org/news...y_new_contributor_to_age_related_hearing_loss
These new nerves replace the missing nerves that were once there and the harder a persons hearing is with background noise and processing sounds, the more of these outgoing dysfunctioning there will be. I'd like to figure out why these new nerves make it harder for someone to hear and why doesn't the brain send out nerves that function like the original did?

Age-related Hearing Loss or Presbycusis is basically the same as hearing loss that has been sped up by noise damage. The only difference is if the noise damaged hearing patient had basically become deaf because of loss to about 90% of their hair cells/nerve synapses. The auditory nerve fibers (afferent & efferent) are easily damaged by loud noise and while it seems that our hearing goes back to its original threshold before the loud noises, that is not the case. Studies have shown that we can lose a large percent of these nerves without affecting the function of the hair cells in the cochlea. When we lose these nerve synapses, we obtain tinnitus and over time like I said before the neurons will eventually die because they aren't functioning like the jobs they were given to you at birth and neurons can't live on their own without vital connections and transferring of neurotransmitters/information to one another.

So really it seems that as a person gets older they lose these working nerve connections over time which could be due to noise or just the aging system and they don't always have ringing like tinnitus patients do. That's because those who get tinnitus through noise have lost a good portion of their nerve fibers. Those aging and reporting hearing problems must be losing these nerve fibers at such a slow rate that either the brain plasticity is changing in time with this loss to where they don't hear much of a ringing or as they grow older they hear a slight ringing that follows them through age because I mean most of the time the elderly aren't attending rock concerts or blasting music into their ears at the gym trying to make gains.

I just think there is a correlation between age-related hearing loss, tinnitus, the auditory nerve, and most importantly our ability to feel emotions & cognitive abilities.

I know that a good portion of these things are intertwined in our existence. Why do a lot people on this site get depressed when they associate themselves with tinnitus. I mean depending on how bad their tinnitus is, they seem more depressed. Most of us know what depression is but why do people get it? People can be prescribed medications to up their serotonin levels or dopamine levels hoping that this will get them back on track in life but that's not always the case and antidepressants can even increase the suicide. When we feel truly happy, sad, or angry we're feeling emotions. Emotions are generally perceived through the hippocampus and amygdala. Sight can give us emotions but most importantly sound is what gives us the most emotions. We hear the voice of a loved one, we hear that song we love that makes us tear up, we experience many strong emotions through what we hear. What allows us to feel emotions? Neurotransmitters sending signals to one another through the emotional regions of the brain allow us to feel emotions. Now what else involves neurotransmitters? Healthy nerve fibers that connect to each of the outer/inner hair cells of the cochlea. Now studies of tinnitus show that this noise can be found all throughout the brain. When you look at a brain listening to music

you see that a good portion of the brain is involved. What allows one to enjoy music? Neurotransmitters functioning properly (the job of the afferent/efferent nerve fibers of the auditory nerve) with our hair cells allowing us to feel good from what sound waves/air our hair cells transfer into electrical currents. What happens when we damage these nerve fibers and develop tinnitus? We feel depressed, down, can't function as well. Why is that? Well we've just lost crucial emotional functioning nerves that gave our brains the ability to experience life like we could before. So without these nerves functioning like before and us developing, yes we are not going to feel as good as the days we did before this all started and yes this will cause us to develop a depression. They don't call these nerve damages a hidden hearing loss for nothing.

I hope some of this information is understandable. I'm just trying to explain how much a well functioning auditory nerve can influence the emotional well being of a person and as we age, age-related hearing loss, we lose these original neurotransmitting nerves that once served a purpose in allowing us to feel emotions from what we heard. The brain needs stimulation to work at its tip-top shape and I believe this all is related to why those with hearing loss issues are more likely to develop Dementia and even Alzheimers.


In Summary: When we're born (unless you are born deaf) we have well functioning neurotransmitting nerve fibers connected to our hair cells. Hundreds to Thousands. As we age, depending on if it's from noise or just aging, we lose these nerves quickly or very slowly over time. When we lose these original nerves, new ones show up but don't act like the original and don't allow us to truly feel the emotions that our original neurotransmitting nerves allowed us to feel. We can lose these nerves so slowly with aging that we don't even realize it. When we lose these nerves quickly, through noise damage, we notice it and that's how we have what we call tinnitus. The brain adapts to this nerve loss and eventually adjusts its emotional response and therefore having tinnitus or a hidden hearing loss, we can feel depressed, have brain fog, not feel like ourselves, or have hearing problems. In the end, these issues that cause changes to the brain can result in the brain not functioning properly and overtime cause Dementia and even play a part in increasing Alzheimers.

 

[Aaron123]

Thanks for your response. I hate to be difficult, but again you state

Clearly when people on this site claim they've gotten rid of their tinnitus, it's either A) the neurons have retracted back and have died or B) the neurons have died,

Neither of the links you gave refers to tinnitus. Can your provide a citation for this claim? And when you write "neurons", are you referring to the cochlear nerve or something else?

It will take me more time to respond to your longer post.

 

[Nick Pyzik]

Thanks for your response. I hate to be difficult, but again you state

Neither of the links you gave refers to tinnitus. Can your provide a citation for this claim? And when you write "neurons", are you referring to the cochlear nerve or something else?

It will take me more time to respond to your longer post.

No problem and it's okay. Neurons are ultimately the same thing as a nerve. The neuron is the whole body of the nerve cell. The brain is made up of billions of neurons. The smaller the brain, the less neurons someone has. The auditory nerve or cochlear nerve is made up of hundreds to thousands of these "neurons" that are first located in the auditory portion of the brain. I'm not sure how these auditory neurons connect themselves to the different portions of the brain like the Motor Cortex, Amygdala, Hippocampus, Cerebellum, etc.....but it must be through interconnected neurons that are associated with the nerves that make up the auditory/cochlear nerve.

This article shows how loss of nerve fibers to hair cells causes tinnitus: http://www.tinnitus.org.uk/tinnitus-and-hidden-hearing-loss

This article talks more about the hidden hearing loss/nerve fiber/loud noises/tinnitus connection: http://www.hearingreview.com/2014/0...anism-nerve-fiber-loss-discussed-asa-meeting/

If you scroll down to hidden hearing loss for this website it actually speaks about the hidden mechanisms of damage in the inner ear that cause hyperacusis. It's the same thing that involves tinnitus: http://hyperacusisfocus.org/innerear/

More hidden hearing loss and tinnitus connections: http://www.audionotch.com/blog/tinn...hearing-loss-you-may-still-have-hearing-loss/

I hope this explains things better. The way I gather most of this information and talk about it is based off of symptoms/reactions I've had with my hearing over the past 5 months to the issues I'm having now since my loud noise hearing incidents and how they match up with the articles/documents I read online. Not to mention I listened to music a lot over the past 6-7 years and I played a lot of shows in a band without protecting my ears.

 

[Reinier]

and neurons can't live on their own without vital connections and transferring of neurotransmitters/information to one another.

I wonder if this is the same as what is mentioned in this link: http://www.els.net/WileyCDA/ElsArticle/refId-a0000803.html

Those aging and reporting hearing problems must be losing these nerve fibers at such a slow rate that either the brain plasticity is changing in time with this loss to where they don't hear much of a ringing or as they grow older they hear a slight ringing that follows them through age

I agree. A sudden event (noise induced loss of connections/hair cells) does not give the brain time to adjust (no time for plasticity). Your summary explains it better I think.

http://acoustics.org/pressroom/httpdocs/159th/liberman.htm
Interesting is that this link you gave (The Biology of Noise-Induced Hearing Loss Cochlear Nerve Loss After Reversible Acoustic Injury) is an article from 2010.
quote from the article: "We believe that the neuronal loss will affect hearing in a noisy environment and may explain why difficulties with hearing in noise increase so dramatically in the aging ear."
End quote. So in 2010 already they where looking at this. (Perhaps even earlier?).

For me finally the penny drops. You contributed to this a lot. I am in your camp.
I also understand why a hearing aid is for this reason very limited. It is useless and perhaps even counter productive to flood the ear with sound. My mother doesn't benefit from her hearing aid. Only in very particular circumstances the hearing aid helps her. I wonder what scientists want to change in the ear to treat age related hearing loss. Regenerating hair cells will not be enough. Like you mentioned when we damage our ears with noise we just speed up the aging process of our hearing. I believe that too now.

The downside is that this could be so much more complex to repair. Perhaps even impossible. If the neurons have retracted can you get them back with gen therapy? I could be wrong. I hope I'm wrong.

I wonder if the regeneration of hair cells in birds is only a partial repair end birds have impaired hearing after noise damage because of the damaged neurons.
Our ears are not so robust after all.
I keep living between hope and despair. Not very hopeful at the moment. I need good news.

 

[Nick Pyzik]

I wonder if this is the same as what is mentioned in this link: http://www.els.net/WileyCDA/ElsArticle/refId-a0000803.html

I agree. A sudden event (noise induced loss of connections/hair cells) does not give the brain time to adjust (no time for plasticity). Your summary explains it better I think.

http://acoustics.org/pressroom/httpdocs/159th/liberman.htm
Interesting is that this link you gave (The Biology of Noise-Induced Hearing Loss Cochlear Nerve Loss After Reversible Acoustic Injury) is an article from 2010.
quote from the article: "We believe that the neuronal loss will affect hearing in a noisy environment and may explain why difficulties with hearing in noise increase so dramatically in the aging ear."
End quote. So in 2010 already they where looking at this. (Perhaps even earlier?).

For me finally the penny drops. You contributed to this a lot. I am in your camp.
I also understand why a hearing aid is for this reason very limited. It is useless and perhaps even counter productive to flood the ear with sound. My mother doesn't benefit from her hearing aid. Only in very particular circumstances the hearing aid helps her. I wonder what scientists want to change in the ear to treat age related hearing loss. Regenerating hair cells will not be enough. Like you mentioned when we damage our ears with noise we just speed up the aging process of our hearing. I believe that too now.

The downside is that this could be so much more complex to repair. Perhaps even impossible. If the neurons have retracted can you get them back with gen therapy? I could be wrong. I hope I'm wrong.

I wonder if the regeneration of hair cells in birds is only a partial repair end birds have impaired hearing after noise damage because of the damaged neurons.
Our ears are not so robust after all.
I keep living between hope and despair. Not very hopeful at the moment. I need good news.

Well Reinier there is good news with this and bad news. The good news is that there have been tests done that involve transplanting new neurons into the inner ear of animals to see if they function like they should and to see if they reach out to the brain stem and come in contact with the hair cells. They did not see great results from these tests but they weren't horrible. I truly think the best route we can go with fixing presbycusis (age-related hearing loss) is through transplanting stem cells that have been differentiated and even mixed with Neurotrophic factors to give these cells the best chance of forming well working spiral ganglion neurons and the different types of nerves that connect with the outer hair cells and inner hair cells. The bad news is that there really aren't any companies working on this and these tests have only been performed by researchers which shows that it will still be a while before they can be perfected and transferred to clinical tests in humans.

But yes, that Dr. Liberman has figured out the issues that have been overlooked by many hearing experts and I hope he comes to more conclusions with his research.

I think both regenerating hair cells and regenerating a healthy functioning auditory nerve are both very difficult and complex tasks. I have a feeling in time there will be a much quicker transition of regenerating hair cells in humans than regenerating the auditory nerve functions in age-related hearing and especially noise related. It's good to know that both are being worked on though and in tine we could possibly have the option to treat these hearing issues.

If you haven't seen these, here are some links to workings with transplanting stem cells to correct the auditory nerve and also a company that has been founded by a large group of researchers.

OTOSTEM - http://www.otostem.org/

Stem Cell Transplant Restores Damaged Auditory Pathways - https://www.ata.org/news/news/new-s...ion-method-restores-damaged-auditory-pathways

More info on transplant technique - http://www.kyoto-u.ac.jp/en/research/research_results/2015/150616_1.html

A PDF on the transplanting and results - http://www.pnas.org/content/112/26/E3431.full.pdf

Article from 2012 using Human Embryo Stem Cells to restore auditory nerve function - http://www.nature.com/news/human-embryonic-stem-cells-restore-gerbil-hearing-1.11402

 

[Reinier]

Thanks Nick.

You have given me some good news (-;
Its up and down all the time.
After reading the different documents I am starting to understand why stem cells could be very helpful. It is amazing that inside this stem cell, information is stored where a neuron needs to go. It is connecting to the hair cell and to the brain. Fascinating!

This is a quote to what I was referring to: "We called this method "surface transplantation". Many cells subsequently entered the nerve tissue, apparently recapitulating elements of their behavior during development. To our surprise they formed functional connections with auditory sensory cells in the ear and to the cells in the hindbrain. Restoration of responses to sound within the brain provided evidence that the auditory pathway had been reconnected. Our results provide hope for patients who might benefit from nerve cell transplantation."
end quote.
And this "surface transplantation" was serendipity in action again (-;

 

[Nick Pyzik]

Thanks Nick.

You have given me some good news (-;
Its up and down all the time.
After reading the different documents I am starting to understand why stem cells could be very helpful. It is amazing that inside this stem cell, information is stored where a neuron needs to go. It is connecting to the hair cell and to the brain. Fascinating!

This is a quote to what I was referring to: "We called this method "surface transplantation". Many cells subsequently entered the nerve tissue, apparently recapitulating elements of their behavior during development. To our surprise they formed functional connections with auditory sensory cells in the ear and to the cells in the hindbrain. Restoration of responses to sound within the brain provided evidence that the auditory pathway had been reconnected. Our results provide hope for patients who might benefit from nerve cell transplantation."
end quote.
And this "surface transplantation" was serendipity in action again (-;

So yes there is work being done on hair cell regeneration and even auditory nerve regeneration. The big question is just when will it be available and in it's most precise and well working form. It's very hard to tell. All we can do is keep pushing on in our lives, hope for the best, and in time try and make an impact on hearing issues to speed up the process of developing a cure so that we and others can feel like ourselves again and experience the quality of life we did before all this happened. We can do it.

 

[Reinier]

Well, you know. what I feel could jump start my life again is something to look forward to. At the moment it is all very uncertain. But this is just a fact of life. Nobody will tell you when or if something will be available. Nobody can.
If I could get the assurance: " in 15 years time there will be something to improve or even heal damaged hearing" I would be elated.
But that's stating the obvious. We all would want this assurance.
In the mean time, this forum gives me support and I will try to use common sense and logic as much as possible.
Lets keep looking out for and share "breakthroughs"