Hearing Loss and technologies to improve hearing


Hearing loss is a common problem that often develops with age or is caused by repeated exposure to loud noises. About 1 in 6 people in the the World have some degree of hearing impairment or deafness. The World Health Organisation estimates 360 million people are affected.

New research, in a paper published in the Journal of Experimental Biology suggests the tiny hair cells responsible for people to hear could be repaired. When these bundles of hairs vibrate in response to sound, cells at the base will send signal to the brain, which the brain then translates into a rich symphony of filling the world with sounds.

Doctors have long believed damage to these hair cells are irreversible, but new research shows that the animal world has similar hair cells in sea anemone, and when damaged those cells are repaired within hours.

The research shows that a protein harvested from sea anemones may be an ointment. When applied to damaged hair cells from mammals, purposely damaged in the ear of a mouse pups, when subsequently treated with the anemone repair protein solution though, the healthy level was reached again.

While repairing hair bundles in mouse ear tissue is not the same thing as repairing those inside the air of people suffering from hearing loss, the research suggest that a treatment may be possible in the not to distant future.

For now the research suggest, only recently damaged hair cells, for example from exceptional loud noises, close cracks of thunder, the emissions of rock-concert loudspeakers, or earpieces from mobile phones can be repaired.

However establishing a forum on Quantified Self allows us to discuss across several disciplines, apply research in 1) hair cell repair 2) in stem cell therapy and 3) in gene therapy. The combination of these therapies allows to cover a broad range of causes of hearing impairment.

Purpose of my work is bringing an improvement to therapies currently available, with your joint contribution to this forum of HEARING impairment and loss.

Best regards,
Alexander Straub

I very much wish for progress in this area. Good luck and keep us informed. Lindsey Meyer gave an excellent talk a few years ago about tracking her sudden hearing loss:

Lindsay Meyer on Tracking Hearing Loss

After experiencing the same SSHL that Lindsay Meyer did, I created my own hearing test, with a much higher resolution, to look at the slope of the threshold-of-perception curve. The one data point per octave test seems needlessly sparse. Here’s my data from one such test.

I was quite surprised by the steepness of the slope in the noise-induced hearing loss in my right ear. I recall measuring significant changes at the edges of the affected frequencies in my left ear as I was taking the steroids prescribed for my hearing loss. Changes that wouldn’t have shown up on a typical, lower resolution test. I cannot find any of that data presently, though.

I haven’t tested my hearing for some time, though. because it’s such a pain to do without an app.

Mark, what equipment did you use for your test? Will you share some details about how you set it up?

While not a cure for Hearing Loss, check out Posit Science BrainHQ’s auditory exercises. I worked for Posit many years ago. It trains the brain to improve the speed of processing of sound which declines with age. Other Posit exercises improve the engram (image of the sound in the brain) for better matching.

A 20 year old, on average, processes sound at 20 milliseconds. A 65 year old processes it at about 120 milliseconds. The result is that the 20 year old has much better sampling and therefore a much easier time “hearing” the conversation.

Many people who did the program remarked that their hearing improved. In reality, the program didn’t improve their hearing, but the sound processing tuneup helped them follow and retain information better. Check out Posit at www.positscience.com. They’ve rebranded but the underlying science hasn’t changed.

Gary, I used a tone generator app for iPad patched into a computer running Logic. I varied the input level, and I could then use the output level control to fade the tone in and out, (since the sudden start and end of any tone will create content in other frequencies.) I would then find the lowest input level that I could perceive. There’s a great deal of uncertainty here in terms of “Did I actually hear something or am I just convincing myself I did?” A randomized, blind test would be much improved, but even so, there seems to be a great deal of meaningful information from my less-than-ideal test.

(I also put a measurement microphone into my headphones and measured the cut or boost I would need at each frequency to compensate for their inaccuracy.)

Yikes - Mark, I see what you mean about the difficulty. I wonder how your approach compared to medical audiometer. There is a rather baffling selection of used audiometers on eBay. Probably a frustrating journey down this route but one I’d like to hear about if anybody has taken it.

I would say that my data is more accurate than an iPhone app, since I actually used a measurement microphone to get an SPL measurement from the headphones at every frequency I tested. I have no confidence that my measurement wasn’t flawed in some way, so it’s almost certainly less accurate than a properly calibrated audiometer. However it’s almost certainly more accurate than an iPhone app. At the end of the day, for SSHL and treatment, change is the primary thing to measure: so as long as your test is consistent, it should give meaningful information. Even the iPhone apps, with their limited resolution and lack of calibrated headphones, can give decent information for a case of profound hearing loss like I experienced. (And combined with tests from properly calibrated audiometers to calculate and compensate for their inaccuracy, they could give very accurate results.)

Further, what seems much more interesting to me is the shape of the curve, and not the specific heights of the points. In most SSHL, as well as noise-induced and age-related hearing loss, the perception threshold curve deviates significantly from the typical, healthy, young individual. You don’t have to know the specific SPL of my threshold of perception at 4 kHz to be able to look at that curve for my right ear and see clear noise-induced hearing loss.

This article raises some of the difficulties of measuring pulsed hearing response. Turning On a Tone.
What was the extent of your amplitude correction after calibration? I would think the human contribution would be much greater than the equipment.
What was the vertical scale on your chart?
Thank you,

I’m not sure why a 1-2 second fade in/out of the tone would not be better than starting it abruptly, regardless of where in the waveform it starts. I’d be curious to know if I’m missing something in that regard.

It has been some time since I did this, but I’m pretty sure the headphones weren’t off by more than 10db at any frequency I was measuring.

The vertical scale is db, but it’s relative db. I think one unit is 5db, but I’m not 100% certain.

I’ve been looking a few different options for my company’s hearing conservation program. I’m learning towards SHOEBOX Audiometry. They have a portable audiometer that seems interesting. Anyone have any experience with this company or similar providers?

I don’t have any personal knowledge in this area but I do remember a Show&Tell talk by Lindsay Mayer who calibrated a simple consumer audiometry app against the results of her office visits: