Unravelling the Mystery of Hyperacusis with Pain

The January / February 2019 issue of ENT & Audiology News, Volume 27, Issue 6, includes an article by Bryan Pollard, President of Hyperacusis Research. The introduction is cut and pasted here and the full article is attached as a PDF.

Unravelling the mystery of hyperacusis with pain

When a person says that sound causes them pain, how can we understand this, and determine what processes are involved? Bryan Pollard navigates us through what is presently known.

Pain has long been underrepresented – and often, completely overlooked – as a component of hyperacusis. The history of the disorder offers insights as to why. The word ‘hyperacusis’ was introduced by Pearlman in 1938. The debate for both the name of the disorder and associated symptoms was underway by 1949 when Tschiassny, in describing sensations of pain associated with noise in Bell’s Palsy, advocated for the use of ‘phonophobia’ (which he defined as hypersensitivity for auditory stimuli) and pointed to other popular terms at the time, such as dysacusis and hyperesthesia acustica. He felt hyperacusis was insufficient for his patients because there was “no increased acuity of the organ of hearing”. In 2014, Tyler, et al, referred to more than a dozen definitions of hyperacusis. Two of these include the term ‘pain’. While numerous other names developed for sound tolerance issues, hyperacusis won out as the dominant name, while phonophobia is common but has come to refer exclusively to the fear of sound.

 

This is amazing that noxacusis (hyperacusis) research is picking up, though I'm worried...



That part about auditory nerve fibers degenerating terrifies me. How will my hearing improve with future regenerative medicine that I am betting my life on? Professor Liberman's research stated that AN fiber to hair cell connections at first just lack ribbon synapses and AN fibers slowly degenerate over the course of weeks, months to years to "decades and longer". Does he still hold that view? Also months to - decades is a long stretch!

The whole point is I'm hoping they can reattach as much ribbon synapses as possibly and the medicine can be in the market in 5-7 years. I take Magnesium, and B12 hoping I can keep the nerves alive (I could be doing nothing).

But still once again actual audiologist will not read this article, they will continue to wander in the quagmire of tonal audiometry and TRT.

 

I'm already making a hypothesis of my own of how hyperacusis will be classified in the near future, I would love for researchers to investigate, I had this model in my head for a while but might as well share it.

Peripheral noxacusis via audiotory nerve
1:
Type II afferents sending pain signals due to massive OHC damage.
OHC's act as the cochlea's amplifiers, therefore damaged OHC's could cause loudness discomfort.

2:
Damage to the auditory nerve itself.
Demyelinization of the AN nerve.


Central noise induced pain
1:
Direct damage (TBI) to the auditory brain or central nervous system associated with hearing, also lack of myelin in the CNS, take multiple sclerosis induced hyperacusis for example.

2:
Hyperactivity in the auditory brain causing NID?
(this hypothesis states that tinnitus and this form of NID are literally two sides of the same coin like phantom sensations of a lost limb and phantom pain)
hypothesizing further and stating that the tensor tympani is the trigger for the phantom pain just like a amputee has triggers on their face to feel a phantom limb. Then again tinnitus actually does have triggers to make it louder such as neck and jaw movement and apparently some people say their hyperacusis is worse when TMD is bad.


Central gain amplification
1:
Auditory processing disorders and some cases of autism, sounds are too loud but never painful, this may also occur in hearing loss as the brain cranks up its internal volume to compensate for lost hearing, but it still could be damaged outer hair cells.

The only thing that's certain is there are certainly several types of noise induced pain and it is far more complicated then Polish business man Pawel Jastreboff could ever imagine, his model was centric to dogma so he could make a quick buck and now's the fun part when it gets torn apart by actual research. Too bad this didn't happen 20 years ago.

 

I just read this article and want to shove it up my last ENT's...

 

So could pain stand as an indicator of an expired therapeutic window?

 

For me, tolerance to sound was never really achieved. Hyperacusis turned slowly (years!) into a combination of hyperacusis, tinnitus and hearing loss. The perceived quality of sound kept getting worse along this journey.

So there was never tolerance or adaptation. My personal experience shows there was just a progressive deterioration of my hearing. Sounds bother me less because I can no longer hear low sounds at some frequencies: there is some hearing loss. However, if sounds are loud enough, they produce recruitment and are perceived very loud, so they can trigger hyperacusis symptoms.

So the evolution has been from many sounds being painful (dragging a chair, closing a door, opening the shower gel!) to some sounds (louder sounds) producing pain. Now it is harder to identify danger, as with earplugs on I wont hear a loud motorbike coming in my direction until it is more or less close. With very bad hyperacusis I once heard the reverse beeps of a construction truck like one mile away.

 

So if I got this right, is your ear pain better due to hearing loss?

 

Yes, my ear pain is better due to hearing loss.

Basically with severe hyperacusis one is all the time on edge and hypervigilant, anticipating any loud noise that may make damage, noise just cuts through ears and head like a knife on butter, even wearing double protection.

With hearing loss some sounds are not heard at all (the very low sound at the frequencies damaged), other sounds are perceived off key, with the wrong tone, distorted etc, and very loud sounds are perceived really loud too due to remnants of hyperacusis and likely recruitment. But in general hearing loss means less sound input, so hyperacusis kicks in less often, life is quieter, but challenging in other ways, like working with hearing loss, social gatherings, going for lunch, stuff like that...

 

If I could, I would sacrifice part of my hearing over hyperacusis.
This burning pain is unbearable.

 

Yeah, I totally understand what you mean... my hearing loss just happened along the way. It was just due to work exposure to loud sound and the odd loud sounds around in daily life. And this happened even though I used protection at all times, earplugs or earmuffs + earplugs. Sound would just cut through me producing all the usual symptoms of hyperacusis, like ear fullness, stabbing pain, massive headaches... weeks of headaches... and progressive hearing loss.

Hearing loss is isolating in a different way, different from hyperacusis, as with hearing loss you can be around but it is hard to concentrate all the time to hear when there is background noise etc In complex hearing environments this is just exhausting. On the bright side, one can go cycling, for a stroll, etc, with caution not to aggravate the hearing loss, but still more relaxed than walking around with severe hyperacusis.

 

Exactly, that's why I think it's much preferable, although I completely get your point regarding the different kind of isolation.

Was your pain constant?

Mine seems constant so, I am pretty worried.
Worried for practical staff, such as making a living.
Bottom line, ear conditions are debilitating. You don't get to reflect on the gift of healthy hearing till you lose it.

 

I know this is an old post, but I wanted to comment that it's been observed that the regenerated hair cells form a nerve fiber as part of the regenerative process. It was discussed on the 1-19 Frequency Therapeutics webinar.

Here's a picture. Note the green line coming off the red cell.



Today, scientists might indeed be observing the nerve fiber decaying, but also observed is a new nerve fiber is created during regeneration to connect that cell to the nervous system. So, it is possible what is seen decaying is also what is regenerated to some extent.

 

No, pain was triggered by sound exposure but lasted for weeks. So one single loud noise could trigger symptoms for weeks, ear pressure, pain, headaches etc

It was pretty hard to get my hearing stable after noise. I would have to rest, avoid noise, etc Spend time at home, being in the quiet. And it just took one loud noise to trigger the cycle of hyperacusis related symptoms again. Over the years this resulted into progressive hearing loss.

 

I'm under the impression that we're absolutely fucked if pain hyperacusis is caused by auditory nerve degeneration, no?

 

I’m inclined to say no, but I’m just a guy on an internet forum. The reality is some people get this really bad and somehow recover and lead a normal life again. Something must be happening then on a biological level to reverse this pain in those cases. I’m speculating, but it’s possible the body can heal itself, however, past a certain threshold of damage it needs regenerative medicine to step in. I always remind myself of the anecdotal cases of people’s hyperacusis improving with cochlea implants, suggesting then that this really is, on a very basic level, an input issue.

Edit: I have been wondering whether the cases that see improvement are not so much down to the reversal of the peripheral changes that initially led to developing the condition, but adaptive, central changes that result from the body recognizing that these pain signals are abnormal and so the brain adapts and plays them down accordingly. That could also explain why some people improve because not everyone’s brain is going to respond in the same way.

 

This makes me think that destructive surgeries that induce deafness might actually destroy hyperacusis symptoms entirely. Obviously not a good idea for anyone with hyperacusis in both ears. But for those with it in just one ear, like me, I feel that it should be on the table.

 

There are people seriously affected by hyperacusis. Some of them make the condition worse without realizing it by using headphones, earbuds or headsets even at low volumes. Listening to music through speakers that might not seem loud but produce low frequency bass, that can be felt as well as heard. This can irritate the inner ear, namely the cochlea and produce a spike. The spike might go away and no harm is done. However, if spikes become a regular occurrence there is a risk of the tinnitus and hyperacusis worsening.

Those that acquired tinnitus from playing music in a band may also develop hyperacusis. It might be very difficult for them giving up their art, so carry on thinking their conditions won't increase. For a while this might be the case but unfortunately too often the opposite is true. If a person doesn't change their lifestyle they risk these conditions becoming increasingly severe.

 

It's all a matter of balancing risks and rewards. See if benefits can outweigh risks.

 

If I continue with this crap for 2 years and it only continues to get worse as it has been, I’m going to be wanting destructive surgery real bad.

 

Maybe the results are uncertain even with destructive surgery.

Tinnitus is quite unpredictable.

 

Yeah, I'm looking into this surgery too. If mine continues for years and years and worsens, that's going to be my last resort. Yeah, deafness sucks, but at least I won't be confined to my house in constant hearing protection.

 

How bad is your audiogram and how quickly did it start to change?

 

Last time I checked it was around 45 dB at 6000 Hz and in the lower frequencies it had dropped to the 15 - 20 dB region.

My audiogram deteriorated first in the higher frequencies and then the loss progressed to the lower frequencies. The lower frequencies are much more important to understand speech etc... but I still manage.

Even a slight loss in the higher frequencies alter music perception and makes music sound quite different.

Audiograms fluctuate a bit and the reading is different depending on the machine where the test is done etc... and of course any cold, throat or nose problem adds to the sensorineural hearing loss making sounds more dimmed.

 

OK. Interesting. I have a few questions if you don't mind.

How about the time frame? You mentioned you have lost hearing fast in the last few years. Was this change/loss measured and how quickly has it changed? Age-related?

I myself have noticed my audiogram moving about 3-5 dB a year in those 4-8 kHz frequencies in one ear. This seems fast when I've mostly been protecting my ears and really limiting noise exposure compared to previous years. One would probably conclude that it's moving by itself due to previous exposure rather than current exposure. Which I assume is what happened to you?

Sorry but I've forgotten your story, did you have long-term noise exposure, if so, from what? Have you stayed away from sounds and continued to have this progression by itself?

 

My hyperacusis was caused by loud noise. It is what people now call "pain hyperacusis". This means pain linger for a long time after a certain sound causes it.

I have lost hearing due to one-off noise exposures, like a car honking around, being exposed to a power tool, etc. All these incidents were obviously unexpected.

Hearing loss happens gradually due to aging and the underlying hyperacusis condition but is usually accelerated by once off noise exposures and then one notices very obviously what caused the loss. So an audiogram can suddenly drop after loud noise, even if the exposure was brief. This is typical of hyperacusic ears.

The brain also plays a role. The brain fills in the gaps to help process sound better, so even if speech, music or whatever is perceived "blurred" or dimmed, if one was good at sounds before (or good at a foreign language), or knew the musical piece, the brain makes up (partially) for the hearing loss.

The flipside: it's harder to learn a new language, with new challenging sounds, if one has hearing loss. It is also harder to appreciate new music one has not heard before.

 

Hi @Juan,

Your statement that hypercusis can cause hearing loss from one-off noise exposure is concerning. You say that this is typical of hyperacusic ears... can you tell me where you get this information from? It is certainly worrying.

Thanks,
Maddy

 

This isn’t typically considered true. This is Juan’s opinion and experience. You may have noticed I’ve asked for age, timeframe and whether this progressive hearing loss has been measured but without an answer, it makes it hard to assess as I’ve never heard this before.

An audiologist would typically consider continued quick-ish moving hearing loss as delayed onset/age-related from long-term noise damage. I don’t think it’s commonly assessed that one second of loud sound will cause you permanent measurable damage just because you have hyperacusis, unless that sound is like 140 dB.

Even then the damage is likely to be mostly temporary in most scenarios. 140 dB is 200x louder than 120 dB. It’s a sound you’d likely never hear in your life, or at least most people won’t more than once.

You should definitely not live in fear as if this is the norm. Hyperacusis ears are very sensitive and you can have setbacks, sensations of muffling, fullness and ringing. Does a loud clanging dish feel like you’ve done damage, yes. Can it create a feeling of trauma in the auditory system, yes. Would it create a 5-10 dB loss? It absolutely shouldn’t.

All those symptoms feel like definitive ear damage/hearing loss but are a reactive auditory system, not so much a system that can have hearing loss caused 100x times easier.

I’ve been through this before and again now. When my hears feel muffled and full, I think I’m going deaf. But this thinking is what can trap some in the hyperacusis cycle. So I’d be very careful fearing that one sound like a car horn is going to cause long lasting damage as that wouldn’t happen in nearly 99.9% of cases.

Just keep measuring your hearing. It’s common to get fluctuations of 5 dB, especially in noise induced 4-10 kHz.

 

From personal experience, and also based on conversations with ENTs and other people with hearing problems.

The typical episode that produces hearing loss is not necessarily a long noise exposure, but a brief very loud noise exposure (like a power tool, siren, car horn, mic or radio feedback etc), that can be combined with other issues that may affect hearing perception as well, like having a cold, a blocked nose or throat etc.

 

If you have hyperacusis, your nerves are damaged. Hitting your ears again with a loud exposure can cause further damage, potentially creating dysacusis/noxacusis.

Hitting them AGAIN on top of dysacusis/noxacusis could cause hearing loss. That hearing loss could take months to gradually manifest.

That's my experience anyway.

 

If you have noxacusis, has the hearing loss helped with the pain? Or helped with the sensitivity and tolerance?