Tinnitus, hearing aids, and the ear/brain system

[cvanc]

Hi all-

Can we talk about tinnitus and related issues?  I bet I'm not the only one here who deals with this.  For me it's 24/7/365.  I've had a recent hearing test and my high frequency rolloff is very significant (down 65dB above 3-4KHz... yes, you read that right, sixty-five dB of treble loss).

The audiologist flatly said the only available treatment was hearing aids.  I have to say the idea of drowning out this continuous sound with some even louder sound does not make sense to me.  I just don't see how that would constitute an improvement.  But I suspect this viewpoint might be an oversimplification and want to kick an idea around with you.

Imagine the ear/brain system has, for lack of a better term, automatic gain control.  Also, perhaps this AGC is more than a simple wideband thing, boosting the entire spectrum when it acts.  It might be frequency-dependent, able to operate over small portions of the spectrum if needed.  Because my 'input transducer' has significant treble loss, this AGC system is really cranking up the high frequency gain in an effort to compensate.  And, in so doing, brings up the noise floor by exactly the same amount, just like an analog gain stage would with a similar change.  And this amplified noise floor is what tinnitus sufferers are hearing.

What do you think?  Thanks.

[Nusa]

I'd say the primary function of the hearing aid is simply to allow you to hear things you need to hear. You can evaluate your own requirements in that regard...are you having trouble hearing things you NEED to hear?

With regard to tinnitus, I gather the idea is to distract the brain with sufficient input that the tinnitus becomes a background sound rather than the primary sound.

You may want to get examined by an appropriate specialist doctor, rather than a mere audiologist. It's possible the underlying cause of the tinnitus is a curable medical problem.

[mtdoc]

Because my 'input transducer' has significant treble loss, this AGC system is really cranking up the high frequency gain in an effort to compensate.  And, in so doing, brings up the noise floor by exactly the same amount, just like an analog gain stage would with a similar change.  And this amplified noise floor is what tinnitus sufferers are hearing.

What do you think?  Thanks.

I think that is very close to current theory on the mechanism for tinnitus - that it is due to increased  gain in higher order CNS auditory neurons that occurs to compensate for the reduced input from lost hair cells in the cochlea.   High frequency tuned hair cells along the organ of Corti are more susceptible to damage than lower frequency hair cells.

[rbm]

I can't contribute to the discussion but can understand cvanc's problem, as I also suffer from tinnitus.  It is distracting at times.  I find though the distraction is much less when I concentrate on something like study or reading.  I also wish for a cure that avoids hearing aids.

[rs20]

Even if the brain had a plain, flat, wideband AGC, then hearing aids would help by increasing the amplitude of the real signal above that of the tinnitus signal; with the AGC therefore attenuating the real signal to a comfortable level and the tinnitus down to a relatively quieter level.

[JXL]

I don't think there is an AGC in our ear/brain system.  I would love to turn AGC off and set gain to minimum, because for me tinnitus is 24/7/365.25 (yes, I don't get that 1 day break every 4 years  ). 
I think hearing aids may make it worse for me, because the perceived ringing gets worse after I'm exposed to loud sounds.
Over the years I have just learned to live it.  When it bothers me it's only when it's when I'm in a very silent environment.

[marshallh]

Go find a practitioner who will give you a DMSA-provoked heavy metal urine test. The test itself returns numbers without a solid reference range but it'll tell you of major problems. I am battling a widespread neurological issue and random tinnitus is one of the things - exacerbated by high lead levels. Mercury buildup especially from amalgam fillings will get into the CNS and interfere with nerve endings. Some people are more tolerant to higher levels of mercury accumulation than others.

Be warned that by dipping into the wild west outside conventional doctors you will have to use your brain and gut sense to find someone who knows their stuff.


Some hearing loss is unavoidable and environmental, but a lot of it will be affected by overall health and other stuff going on in the body. You are somewhat justified to question the audiologist who insists there is only 1 way to go about fixing the problem.

[nanofrog]

I can't contribute to the discussion but can understand cvanc's problem, as I also suffer from tinnitus.  It is distracting at times.  I find though the distraction is much less when I concentrate on something like study or reading.  I also wish for a cure that avoids hearing aids.

I have it as well, and has been the case for as long as I can remember.

FWIW, I usually have music playing in the background so I pay less attention to the ringing. Mine sounds like a CRT fly back transformer whine, and it makes falling asleep difficult if the room is silent or nearly so. The fact I'm also an insomniac doesn't help matters either.   

[cdev]

A great many toxicants deplete our body's store of glutathione..

There may be a connection between glutathione status and tinnitus. N-acetylcysteine which is the best value rate limiting precursor of Glutathione also may be useful in reducing the body's burden of some metals (its a thiol like succimer, but not such a strong binder of metals.) Another thiol that may be useful is alpha lipoic acid. (an older name for it is thioctic acid)

I also know that taurine, a sulfur containing amino acid,  is useful in protecting the body from metal intoxication.

But first things first. Have you ever tried supplementing with n-acetylcysteine? Older people should take it daily because the older we get the more glutathione is used up by processes within the body that increase as we age. So you need more to protect your cells angainst innumerable toxic chemicals in the environment, sunburn/radiation, a great many things.  If your cells dont have it available at the specific moment its needed, they have to commit suicide and that uses up your body's ability to produce new cells to replace them. https://en.wikipedia.org/wiki/Hayflick_limit

Cell division is a finite resource that people should try to conserve - especially because of global warming which will mean lots of additional exposures, mercury, and mold are two obvious ones .



 N-acetylcysteine also improves your hearing's resistance to insults (Including loud sounds). Its protective of hearing and the reason is almost certainly the improvement caused by improved intracellular stores of glutathione.

I would also do some reading on inosine.

I would not be surprised if inosine helped restore partial hearing. Inosine is a purine and is useful in cases of partial nerve damage. But in order to work it has to be taken multiple times a day over a period of time. Companies have tried to commercialize it by figuring out various ways to deliver it in a time released manner .

I credit inosine as helping restore my sense of smell (which was completely gone) that I lost due to a heavy mold exposure.
The mold also caused really savage tinnitus, splitting headaches and numerous other problems.

[cdev]

Here!


A randomised, double blind trial of N-Acetylcysteine for hearing protection during stapes surgery.

Bagger-Sjöbäck D, Strömbäck K, Hakizimana P, Plue J, Larsson C, Hultcrantz M, Papatziamos G, Smeds H, Danckwardt-Lillieström N, Hellström S, Johansson A, Tideholm B, Fridberger A.
PLoS One. 2015 Mar 12;10(3):e0115657. doi: 10.1371/journal.pone.0115657. eCollection 2015.PMID:25763866
Free PMC Article
Similar articles

Select item 247086402.

Using prophylactic antioxidants to prevent noise-induced hearing damage in young adults: a protocol for a double-blind, randomized controlled trial.

Gilles A, Ihtijarevic B, Wouters K, Van de Heyning P.
Trials. 2014 Apr 5;15:110. doi: 10.1186/1745-6215-15-110.PMID:24708640
Free PMC Article
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Select item 240515613.

Deserves a hearing? A case report of remitting tinnitus with N-acetyl cysteine.

Dean OM, Jeavons S, Malhi GS, Cotton SM, Tanious M, Kohlmann K, Hewitt K, Moss K, Allwang C, Schapkaitz I, Robbins J, Cobb H, Dodd S, Bush A, Berk M.
Afr J Psychiatry (Johannesbg). 2013 Jul;16(4):238, 240. doi:

http://dx.doi.org/10.4314/ajpsy.v16i4.31.

No abstract available. PMID:24051561

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Mechanisms and treatment of blast induced hearing loss.Choi CH.
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[cdev]

There may be some value for tinnitus sufferers in a number of other antioxidants and phytonutrients.

Its definitely worth looking into. Because pro-oxidant substances often cause programmed cell death antioxidants are valuable for neuroprotection generally.

[eyiz]

Holy nad. The unstruck sound. That's what the Buddhists and eastern gurus call it. You can change the pitch of the ringing in your ear through meditation. In the west, it's a pathology, in the east it's a blessing. Go figure. When a person begins to develop spiritually, the sound appears automatically. By concentrating on the sound, you can increase the volume, change the pitch, and use it to alter states of consciousness. Of course, if you're not interested in psychic phenomena and altered states of mind, then its just a problem, and a nuisance. The same with all siddhi powers,  they are completely disturbing to those who just want to lead an ordinary life, like most other people. When the kundalini awakens in the unprepared individual all these unusual manifestations begin to appear. You could research all these things, and develop a liking for the phenomena, or you can adopt the view that it's a problem that needs medical treatment. But, be aware, anything the west doesn't understand, is considered a pathology, something to be fixed with medication or treatments. If you want a balanced view, find a spiritual guru, get some answers on the other side of things, see a different point of view.

[cdev]

Has anybody ever tried to determine the actual frequency of a tinnitus sound and maybe beat (heterodyne) against it?  Can it be determined with a signal generator. I know that sometimes I will hear a perceptible shift in the frequency. I associate higher frequencies with more exposure of whatever it is. There is always a cause if I look for it.

There are slight differences in visual contrast sensitivity which are easy to measure and which can give you a way of evaulating your level of toxic exposure.

[rs20]

I'm confused, are you proposing N-Acetylcysteine as a solution, or disproving its effectiveness? Because the first paper you linked strongly fails to find any link between N-Acetylcysteine and hearing improvement (p = 0.54), then the next is just a protocol for how a study should be performed AFAICT, and the third is just a N=1 case study. Lost interest after that, seemed to no longer be anything to do with N-Acetylcysteine anymore?

Here!


A randomised, double blind trial of N-Acetylcysteine for hearing protection during stapes surgery.
...

[jh15]

cdev,

I was playing with sine generators and trying to get a beat note. Didn't succeed, but googling or youtube, I found someone trying to do the same thing.

I was going to try and pick up anything emitted by the eardrum, (hadn't proved that, but heard it might be possible) sync it and reverse phase it.

This guy was doing the exact plan I had. He didn't succeed so far.

Not sure if I came across it while reading Forrest Mims, and he had a link or what.

Oh, a loud bell clanged, and the guy lost his tinnitus temporarily for a long time.

FYI I waited years on an Indigogo hearing aid, and love them. You get a calibration with special phones, a physician or whatever, can change curves with your laptop, and several settings for environment with a magnet held near them to change while in public.

Called ihearmedical.com.

I only use them in public 'for the other guy'.  I don't like things in my ears, and this:

Sounds above a certain level damage your ears don't they?

If your aid is pumping 100 db of correction, won't that blast the remaining hairs? So I keep use to a minimum.

I do love them though, and it was hundreds, not thousands.

[helius]

Has anybody ever tried to determine the actual frequency of a tinnitus sound and maybe beat (heterodyne) against it?  Can it be determined with a signal generator. I know that sometimes I will hear a perceptible shift in the frequency. I associate higher frequencies with more exposure of whatever it is. There is always a cause if I look for it.

http://www.notchtherapy.com

You cannot "beat" the sound of your tinnitus against a sine wave because it is not a real sound. Beat interference is only applicable to objects that obey the wave equation, and the neuronal impulses that cause tinnitus do not. The only way to find the frequency is to subjectively identify its pitch: if you are completely tone deaf you cannot do this.

[VK5RC]

Tinnitus is a risk factor for the development of hearing loss and often accompanies hearing loss but hearing loss is by no means a certainty following tinnitus . I have it, for me it is definitely a 'pink noise' - not a single tone. 
Antioxidants are not a panacea - in smokers they actually increase the risk of lung cancer.
If hearing loss really bad - cochlear implants can help a bit.

[tggzzz]

Only 65dB down? Lucky you

Be aware that the ear-brain system is highly non-linear in any dimension you can think of.  Hence applying "electronic engineering" reasoning to it is of limited value.

There are many many manifestations of tinnitus; what works for one person may or may not work for other people. In very rare cases the inner ear can actually generate sounds that can be heard by external equipment.

If you need two hearing aids, get them. If you only have one then firstly your hearing won't be improved as much as possible. Secondly there is a phenomenon where, if the ear-brain doesn't hear for a while, then it "forgets" how to hear and it isn't possible to reinstate it with a hearing aid.

There is a large deal of suck-it-and-see when it comes to reducing hearing problems; this is a problem if each "suck" costs a lot of money. A "try before you buy" scheme is helpful; I'm very grateful for the NHS since they have several options available, all free.

[b_force]

Has anybody ever tried to determine the actual frequency of a tinnitus sound and maybe beat (heterodyne) against it?  Can it be determined with a signal generator. I know that sometimes I will hear a perceptible shift in the frequency. I associate higher frequencies with more exposure of whatever it is. There is always a cause if I look for it.

http://www.notchtherapy.com

You cannot "beat" the sound of your tinnitus against a sine wave because it is not a real sound. Beat interference is only applicable to objects that obey the wave equation, and the neuronal impulses that cause tinnitus do not. The only way to find the frequency is to subjectively identify its pitch: if you are completely tone deaf you cannot do this.

I was actually wondering about this. I do think you can do something with phase shifting/delay.
In the end, ANY type of sound (virtual, real or not) has some sort of phase.
My girlfriend has pretty bad tinnitus. She is pretty musical so therefore we could track down the most important frequencies (yes she has multiple, which makes it so much worse).

I still have to make a test setup to see if we can make it actually more manageble.

There is onlly another side of the story. I don't know if it makes the problem worse if people have hearing damage. Normally those people need to be carfull with any type of extra noise and loud sounds. Does that also works for "out of phase" signals?


Btw, an old friend of my works for a big hearing-aid transducer company. Did you know those things leave their factory for 1-2 bucks, incl profits etc!!!
In the store you pay easily $600-$800 for those bloody things.
Some middle man in between knows how to fills his pockets......

[tggzzz]

Btw, an old friend of my works for a big hearing-aid transducer company. Did you know those things leave their factory for 1-2 bucks, incl profits etc!!!
In the store you pay easily $600-$800 for those bloody things.
Some middle man in between knows how to fills his pockets......

It is always easy to underestimate the costs of "the last mile". As a rule of thumb in non-commodity retail industries, the retailer doubles the cost of the product to them. It will be worse in this industry due to...

I presume there will be significant expenses associated with fabricating custom acrylic/silicone ear inserts, buying audiology equipment, gaining certification, learning about the merits of specific products, dealing with "it doesn't work well" rejections, failures in normal use, home visits for assessment, retail premises, product volumes, ...

Besides, the transducers are the least interesting part of the hearing aid. Making a DSP run on 1V for weeks on a small battery shouldn't be underestimated. Their semiconductor processes are entirely dissimilar to processors/memory/logic etc!

[Gary.M]

Btw, an old friend of my works for a big hearing-aid transducer company. Did you know those things leave their factory for 1-2 bucks, incl profits etc!!!
In the store you pay easily $600-$800 for those bloody things.
Some middle man in between knows how to fills his pockets......

Hearing aids for $600-800? If you're talking AU/NZ$ more like $1000-3000 per ear!



Sent from my x600 using Tapatalk

[b_force]

Btw, an old friend of my works for a big hearing-aid transducer company. Did you know those things leave their factory for 1-2 bucks, incl profits etc!!!
In the store you pay easily $600-$800 for those bloody things.
Some middle man in between knows how to fills his pockets......

It is always easy to underestimate the costs of "the last mile". As a rule of thumb in non-commodity retail industries, the retailer doubles the cost of the product to them. It will be worse in this industry due to...

I presume there will be significant expenses associated with fabricating custom acrylic/silicone ear inserts, buying audiology equipment, gaining certification, learning about the merits of specific products, dealing with "it doesn't work well" rejections, failures in normal use, home visits for assessment, retail premises, product volumes, ...

Besides, the transducers are the least interesting part of the hearing aid. Making a DSP run on 1V for weeks on a small battery shouldn't be underestimated. Their semiconductor processes are entirely dissimilar to processors/memory/logic etc!

That still doesn't explain a factor 800 or more!
Btw, this where the precies a few years ago, without fancy DSPs. Most of them actually use a very simple passive filter.

But even with DSP these prices are insane.
There is absolutely no technical excuse for it.
(I have been long enough in the audio field to have a good sense for that)

[tszaboo]

I had tinnitus for some time. Maybe years. It wasnt very loud, disturbing me or anything.
I was able to cure it. Basically, I wear ear mufflers, whenever I feel like it. Usually an hour, maybe two in a day. I wear it when I do something loud, power tools, even vacuum cleaning. I wear it, when the noise from the street is annoying me. I wear it when the neighbors do too much noise at 2 AM.
Mine is 3M Peltor X5A, this was claiming to have the best protection from their lineup, -31dB, that is a lot.

You look funny in it, sure. I dont care. Best 30 EUR I've spent in my life. Although, I also clean my ear regularly since, and I've been taking vitamins. Might have been those. In any case, I get annoyed by sounds made by other people (called misophonia*), so the ear protector is still a huge win.

Misophonia:

Misophonia, literally "hatred of sound", was proposed in 2000 as a condition in which negative emotions, thoughts, and physical reactions are triggered by specific sounds.

I hate people walking like a 2 ton cyberman, people hitting things together for no good reason other than to make the noise, smashing doors, leaving their 19 century tractor car standing below my window with running engine, motorcycles.

[tggzzz]

Btw, an old friend of my works for a big hearing-aid transducer company. Did you know those things leave their factory for 1-2 bucks, incl profits etc!!!
In the store you pay easily $600-$800 for those bloody things.
Some middle man in between knows how to fills his pockets......

It is always easy to underestimate the costs of "the last mile". As a rule of thumb in non-commodity retail industries, the retailer doubles the cost of the product to them. It will be worse in this industry due to...

I presume there will be significant expenses associated with fabricating custom acrylic/silicone ear inserts, buying audiology equipment, gaining certification, learning about the merits of specific products, dealing with "it doesn't work well" rejections, failures in normal use, home visits for assessment, retail premises, product volumes, ...

Besides, the transducers are the least interesting part of the hearing aid. Making a DSP run on 1V for weeks on a small battery shouldn't be underestimated. Their semiconductor processes are entirely dissimilar to processors/memory/logic etc!

That still doesn't explain a factor 800 or more!
Btw, this where the precies a few years ago, without fancy DSPs. Most of them actually use a very simple passive filter.

But even with DSP these prices are insane.
There is absolutely no technical excuse for it.
(I have been long enough in the audio field to have a good sense for that)

The issues I alluded to weren't technical; they were the commercial "cost of doing business" - and those cannot be derived from technical considerations.

Since you are "in the audio field", what costs would you assign to:

• NRE costs of developing a new hearing aid, and getting it on the market. Please indicate what you have and haven't included (e.g. catalogues, inventory, regulatory, advertising, accounting, instruction manuals etc etc)
• NRE costs a retailer has when selling the first example of a new hearing aid. Please indicate what you have and haven't included (e.g. audiology equipment, hearing aid programmers, training, advertising, professional fees etc etc)
• costs a retailer has when selling every hearing aid. Please indicate what you have and haven't included (e.g. number sold per year, time taken to test hearing and take moulds, mould manufacture costs, fitting and tweaking time, discuss alternatives with client, secretarial overheads, expected proportion of complaints/breakages etc etc)
• costs associated with buildings, taxation and other "bad stuff"

I think you will find the component and manufacturing costs are a very small fraction of the total costs.

As a small example, in an efficient large busy UK hospital, I (as a client) would expect to take at least three hours of an audiologist's time. Now, as a rule of thumb, assume that the cost of employing a technical professional is 2.5 times their salary. So, picking figures out of thin air, if someone earns £40000/year, the hourly cost of employing them will be ~65/hour => ~£200 per client. On top of that you have to add the "retail" NRE costs, and manufacturing costs; I can't estimate either of them. So, with a traditional retail markup of 100%, you are looking at £400 plus 2*NRE + manufacturing costs. And at that point you aren't so far from £800.

So even a crude back-of-an envelope calculation gives a feel for how the costs quickly mount up.

Of course, if you know that the prices are excessive, there's nothing stopping you entering the market yourself, and becoming very rich!

[cdev]

NAC is the precursor of glutathione.
Many kinds of hearing loss involve pro-oxidant processes. So consuming the most bioavailable direct precursor of glutathione has been shown many times to be helpful as it improves GSH (or redox status). GSH levels decline in all older people due to much of it being used up by physical changes that occur in cells which deplete GSH.

 Inosine is a trophic factor that helps damaged axons heal.

[mtdoc]

Tinnitus, like many conditions that traditional, allopathic medicine has no good solution for, tends to attract all kinds of alternative therapies and theories.   Sometimes those things pan out and are proven effective but often they don't.  There may be a theoretical basis for thinking NAC might help tinnitus but AFAIK - and despite what some of the companies marketing it may say - it has not been shown to be effective in any controlled studies.  It would be great if it did work, but...

Now whether it has an oto-protective  effect is a different question and one that is harder to prove or disprove. But there are well known, effective oto-protective methods so .....

And in case anyone thinks there is some medical conspiracy to deprive the world of the benefits of NAC - that's just not true. It is already used exensively in medicine -to treat acetaminophen overdoses, to protect the kidneys from effects of radio-contrast dye, and as a mucolytic

[cdev]

I'm looking for this study but can't find it on pubmed.

Do you remember any more info on it?


Quote from: VK5RC on Yesterday at 23:17:39

Antioxidants are not a panacea - in smokers they actually increase the risk of lung cancer.
If hearing loss really bad - cochlear implants can help a bit.

[cdev]

Indeed there are well-known otoprotective methods!

https://www.ncbi.nlm.nih.gov/pubmed?term=acetylcysteine+otoprotective&cmd=DetailsSearch

(not the best search term to find stuff about it - related links bring up a LOT more - but specific to the conversation)

Now whether it has an oto-protective  effect is a different question and one that is harder to prove or disprove. But there are well known, effective oto-protective methods so .....

[Richard Crowley]

Tinnitus and hearing-loss are two completely separate and independent symptoms.  Amplification (hearing-aids) is the obvious solution to hearing-loss (i.e. decline of sensitivity in engineering terms.)  It has nothing to do with tinnitus.  It is the same solution whether you suffer from tinnitus or not.

I suffer from tinnitus and it is definitely not a single discrete frequency, or a fixed harmonically-related cluster of frequencies.  It has characteristics of a non-specific chronic drone pitch, but with features of randomness like white/pink noise thrown in.  It seems unlikely that one could counteract it with an external signal (like popular "noise-cancelling" headphones/earbuds).

With aging, I find myself more and more saying "what did you say?".  But in my perception it isn't that I didn't hear them the first time, I was just tuning them out and thinking about or paying attention to something else.  Or at least that is my story and I'm sticking to it.

[MT]

Hi all-
The audiologist flatly said the only available treatment was hearing aids.

Assar Bjorne, a Phd doctor and dentist at YTS unit in Sweden discovered that some of his patients when
undergoing a local anesthesia the tinnitus disappear'ed. Other studies have shown that some tinnitus cases
could be related to squeezed nerves in the neck. Audiologists are the last people you should ask for help.

Some papers about this at their site:
http://yts.se/forskning-och-publikationer/

[cdev]

Just found this when I varied my search term a bit..

http://www.medscimonit.com/download/index/idArt/869487

 Different strategies in treating noise-induced hearing loss with N-acetylcysteine Guiscardo  Lorito, Pietro  Giordano, Joseph Petruccelli, Alessandro Martini , Stavros Hatzopoulos
Med Sci Monit 2008; 14(: BR159-164
ID: 869487
 
Background: The cellular mechanisms leading to noise-induced hearing loss (NIHL) involve the generation of reactive oxygen species (ROS). Recent studies on glutathione (GSH) and N-acetylcysteine (NAC) show that they can protect the cochlea from ROS-derived damage, increasing the levels of endogenous cellular defences. The purpose of this study was to verify NAC's oto-protective efficacy and determine if drug administration timing influences the degree of oto-protection.
 Material and Method: Forty male Sprague Dawley albino rats were divided in four groups exposed to 8-kHz 105-dB SPL continuous noise. The groups were treated with diverse NAC administration modalities: group A received 4 injections during 48 hours (pre- and post-noise exposure), group B 1 injection prior to exposure, group C 1 injection 24 h after exposure, and group D served as untreated controls. The single injection dosage was 375 mg/kg; the controls received an equal volume of saline solution. Cochlear function was assessed by pre- and post-noise (after 168 hours) recordings of distortion product otoacoustic emissions (DPOAEs) and auditory brainstem responses (ABR). DPOAEs were obtained by three different asymmetric protocols (P1=60-50, P2=50-40, P3=40-30 dB SPL) for frequencies of 4-16 kHz. ABR responses were elicited by tone-bursts at 8 and 16 kHz.
 Results: The most important outcome of the study was that the administration of NAC significantly reduced the threshold shifts in the treated animals. NAC provided different degrees of threshold reduction according to the timing of the drug injection.
 Conclusions: The role played by the timing of NAC injection was important for the OHC protection index. From a DPOAE perspective, the best protection scheme was observed in the group receiving NAC after noise exposure, but full recovery of cochlear function was not observed in any of the tested groups. http://www.medscimonit.com/download/getFreePdf/l/EN

[Habropoda]

In many cases tinnitus is related to hearing loss.  In my case it seems to be similar to phantom limb syndrome, where the brain fills in for a missing limb, or the blind spot in our eyes, where the brain fills in with a matching background or even completes a line (http://serendip.brynmawr.edu/bb/blindspot4.html).  In this case my lower brain seems to fill in some of the missing part of my hearing completely on its own, whether I pay attention to it or not

While ignoring it is a good thing to do, some sounds break it up or make it vary at that “fill in the blind spot” level.  Even if I pay attention to it, cricket sounds break it up and some tones make it vary. 

I keep thinking there might be a way to trick that low level part of the brain similar to the way they treat phantom limb pain by having someone clench and unclench a mirror image of their limb:  https://en.wikipedia.org/wiki/Mirror_box  Perhaps the notch therapy mentioned above or something where the brain tells itself “now everything is noisy” and then “now everything is quiet”.

Of course a pill would be preferable.

[rs20]

Just found this when I varied my search term a bit..

http://www.medscimonit.com/download/index/idArt/869487

 Different strategies in treating noise-induced hearing loss with N-acetylcysteine Guiscardo  Lorito, Pietro  Giordano, Joseph Petruccelli, Alessandro Martini , Stavros Hatzopoulos
Med Sci Monit 2008; 14(: BR159-164
ID: 869487

Interesting results; the first that you have presented that are remotely positive with respect to the benefit of N-acetylcysteine to hearing loss. However,
a) This thread is about tinnitus, so not relevant
b) The study is on mice, unlike humans that were used in the first study you presented which showed no benefit to N-acetylcysteine
c) The post-treatment in the study was injected 24 hours after exposure, where it plausibly has far more opportunity to help than an injection years later as would be the case for tinnitus treatment (again, the first negative study you presented is more useful in this respect)

In short, the first study you presented was such a slam dunk dismissal of N-acetylcysteine as applied to real humans in realistic circumstances that your attempts to find other studies to back up your pre-held beliefs are pretty crystal clear case of motivated reasoning/confirmation bias.

The sum total of the research you have presented so far still combines to this: the idea of using N-acetylcysteine as a years-later remedy for humans seems extremely poorly backed up (if not dismissed by your first reference), to the extent that it is irresponsible to give people false hope by pushing it as a suggestion.

[cdev]

rs20, please don't put words in my mouth.

Those otoprotecton papers are specific to the situations they describe.

Since the 1940s, its been illegal under international law to perform medical experiments on humans without informed consent, and a clear plan likely to bring benefits to both the patient(s) and all humanity.
Experiments have to be approved by panels (and be likely to work, or at least plausible.).

Also it is and should remain illegal to behead human beings and analyze the relative density of different kinds of cells in their ears after subjecting them to various experimental conditions.

(/sarcasm)

All this said, occasionally I do get tinnitus, and its always caused by something. Mold is a common causative agent, and Ive learned that its a reliable indicator of hidden mold for me.

When I get that ringing, loud sounds become painful. This is almost certainly due to low glutathione and indeed, that ringing seems to be prevented by NAC.  I know this from personal experience. It happens all the time. Its almost as if I have a sixth sense, my ringing ears.

Its been shown that a great many common toxicants share this same pathway BTW,

[rs20]

All I'm saying is; there's a massive disconnect between A) the claims/anecdotal evidence you're presenting (including in your most recent message), and B) the research papers you're presenting. Since the latter ostensibly are presented to support the former, I feel it's only right for me to point this out -- for the benefit of those who may be convinced/wowed by journal references without taking the time to dig deeper.

I am by no means any sort of expert in this field; I just call out taken-out-of-context and BS research when I see it.

Again, the first study you present was performed on humans, and failed to find any benefit.

[cdev]

rs20, I'm very sorry but you're totally misunderstanding what I posted and and what I was trying to say.

Maybe seeing the wider picture would be helpful!

[Simon]

I had tinnitus for some time. Maybe years. It wasnt very loud, disturbing me or anything.
I was able to cure it. Basically, I wear ear mufflers, whenever I feel like it. Usually an hour, maybe two in a day. I wear it when I do something loud, power tools, even vacuum cleaning. I wear it, when the noise from the street is annoying me. I wear it when the neighbors do too much noise at 2 AM.
Mine is 3M Peltor X5A, this was claiming to have the best protection from their lineup, -31dB, that is a lot.

You look funny in it, sure. I dont care. Best 30 EUR I've spent in my life. Although, I also clean my ear regularly since, and I've been taking vitamins. Might have been those. In any case, I get annoyed by sounds made by other people (called misophonia*), so the ear protector is still a huge win.

Misophonia:

Misophonia, literally "hatred of sound", was proposed in 2000 as a condition in which negative emotions, thoughts, and physical reactions are triggered by specific sounds.

I hate people walking like a 2 ton cyberman, people hitting things together for no good reason other than to make the noise, smashing doors, leaving their 19 century tractor car standing below my window with running engine, motorcycles.

I have the same problems, I hate undue noise and am particularly sensitive to low frequency sounds, when i worked in a print shop the pressure waves from the large sheets of paper and worse card (300g/sqm) would leave me dazed, although not an audible sound I ws impacted. Ear muffs were a god send and I often take out the inner foam so that I can hear people talk but not the pressure waves from machinery.

My latest annoyance is hand driers work have just installed, with a non sound proof floor between the downstairs toilets and the office the sound of hand driers spinning up and down all day is very annoying, the one in our office toilet bearable as it gets less use and no doubt the resonance in the downstairs toilet creates low frequency sound tuned to the size of the room and filter by the floor.

I have tinitus that usually is of the high pitch type like a CRT HT transformer whistle, I think a jet engine at some point in it's operating range will make the exact same sound to the point I can believe that it's not my tinnitus but the engine only. Other times it can be like a car engine idling and that is really annoying.

Tinnitus is also stress related I have heard.

[cdev]

Simon,
Chemicals commonly used in printing, such as inks and 2-Isopropylthioxanthone (2-ITX) contain "agonists of the aryl hydrocarbon receptor" (AhR). (better known as the dioxin receptor)

I don't know what mechanism is involved in my own personal reaction but
sometimes reading a freshly printed document will make my ears ring like crazy.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2855230/

Freshly dyed clothing sometimes too.  Brand new blue jeans, for example.

[Simon]

Yes the chemicals can no doubt be a bad idea but I would also go to sleep to the sound of printing presses that were not there. I have only recently learnt the difference between and idling car outside and what sounds like an idling car. For that one turning over usually does the trick or exerting some muscle in my ear. I have have a hair lip and cleft pallet which apparently means my eustacian tubes will not be perfectly formed and will block more easily, I don't know if pressure build up's can cause noise in the ear, maybe that idling engine sound as air "bubbles" through slowly equalising the pressure.

[TheWelly888]

If hearing loss really bad - cochlear implants can help a bit.

I have a cochlear implant. I would like to point out that the hearing loss would have to be so bad that acoustic hearing aids cannot help at all - ie at least 100dB hearing loss! I was given to understand that tinnitus would not disappear completely after the implant activation, in fact it is still there but only noticeable when I don't wear the processor at night.

I have had tinnitus for as long as I can remember (I was born deaf) and I found that paying no attention to the tinnitus helped me deal with it - sometimes I made the tinnitus play a tune in my head or even imagine it was the sound of my favourite diesel locomotive!

[Dataforensics]

I can only relate my own experience. Developed tinnitus in one ear back in 2012 sounds like a noisy high pitch whistle and is 24/7.
Many doctors,tests and trial medications to no effect before I could get NHS to do hearing tests.
Was told I had age related high frequency degradation and some damage from a very loud noise in the past.
I to was reluctant to get a hearing aid possibly due to vanity or not willing to accept older age.
However the UK NHS provided me with one that is tailored to my frequency response last September.
The affect was amazing, the tinnitus was nearing unbearable before, but now I only notice it when I take the aid out or if I try to concentrate on hearing it.
And until getting the aid I never noticed how much my hearing had degraded, much easier to understand people talking in any sort of noisy environment.
Of course everybody is different so a hearing aid might not work for you.