Cookie-Bite Hearing Loss and Hearing Aids

by Neil Bauman, Ph.D.

April 11, 2016

A young lady wrote,

I am hard of hearing and have been diagnosed with what is called a “cookie-bite” hearing loss. This means I cannot hear certain sounds or ranges of sounds but I can hear other sounds just fine. I have accommodated my hearing loss most of my life by speechreading, using headphones & Facetime for talking on the phone, and closed captioning for viewing movies, etc.  I would say that I have a moderate hearing loss.

Approximately 8 years ago I tried hearing aids and the whole experience was awful. I tried many different types and I tried the latest technology at the time. I went back to the doctor once or twice a week (over a period of 3 months) to adjust it and try to get it just right. It was an awful experience because the sounds that I could hear were way too loud for me and drove me insane. Yet, I still found myself having to speech read and use captioning because, although everything was louder, it was not to the level of clarity I needed to understand what was being said. So overall it did not improve my quality of life. 

Fast forward to the current time and my family is bugging me to try hearing aids again. They get frustrated with me because they do not want to adjust their behavior because I cannot hear. I cannot seem to convince them that hearing aids are not a cure-all; that they will still have to let me see them when I talk to them.

I just wanted to hear your thoughts on trying out hearing aids again.

As you know, a cookie-bite hearing loss is where you hear the low and high frequencies better than you do the mid-frequencies. (It got its strange colloquial name because it looks like someone took a bite out of the top of your audiogram.) In your case, your hearing in the lows and highs is normal, but you don’t hear well in the mid-frequencies where many speech sounds occur.

I know what this is like. I used to have an extreme reverse slope loss hearing loss, but as I’ve aged, it has morphed into a cookie bite loss that bottoms out around 80 dB in the mid frequencies and rises to about 60 dB at the low and high ends.

You have used good coping strategies—speechreading, captions, Facetime, headphones, etc. I have done much the same all my life.

I too understand your frustrations and problems with trying to get hearing aids fitted to your specific hearing loss.

One of the problems is that fitting any hearing loss other than the standard ski-slope loss is more difficult. Furthermore, audiologists and hearing aid dispensers don’t have much experience fitting people with such losses since the vast majority of people they see have ski-slope hearing losses.

Another problem is that they feel they have to meet the target “prescription” the fitting protocol gives them—yet that volume of sound is too loud for you—especially at the beginning. Too often, audiologists and hearing aid dispensers are slavish to their “stupid” prescription, rather than listening to you—the person with the hearing loss. The prescription is a good place to start to be sure, but then they need to modify it to specifically fit how your brain understands speech.

The secret is to set the levels for what is comfortable to you–and forget about the prescription. Furthermore, and I’ll bet many don’t have a clue about this—if you wear ear molds that block outside sounds, you are actually hearing worse than you did without hearing aids.

This is because in order to understand speech, you need to hear the high-frequency, consonantal sounds. If you wear ear molds without vents large enough for these sounds to get in, you can’t hear them because your hearing aids do not amplify these sounds. Typically, hearing aids only amplify up to 6 or 8 kHz, but normal hearing goes up to 20 kHz. The result is that by wearing hearing aids you have made yourself deaf in the higher frequencies. Yet it is these very frequencies that your brain has depended on all these years in order to interpret the speech you hear.

The reason I know this is happening is that you say you can hear speech (much too loud with hearing aids), but you still can’t understand speech well. This is because you are not hearing the higher-frequency sounds that give speech most of its intelligibility.

If I were in your shoes, I’d get hearing aids with open-fit ear molds so any sounds you naturally hear get into your ear canals unimpeded. Then, only amplify those sounds you can’t hear in the mid range—but not make them too loud.

Likewise, you don’t want any amplification in the low frequencies either. That can quickly make everything sound too loud—but again, you need open-fit ear molds so the low-frequency sounds you normally hear can also get into your ear canals.

Getting family to understand hearing loss and properly accommodate you is typically a big struggle. Hearing people typically don’t want to put themselves out for us. They think it takes more effort than it is worth—not realizing that when they do this, they are really saying we are not worth their effort.

They want us to put out all the effort. They fail to realize that communication is a two-way street, and that they have to do their part. We can only do so much.

Furthermore, too often, hearing people think that hearing aids are the cure for hearing loss. Therefore, they don’t have to accommodate our hearing losses. It’s all done by the hearing aids.

Nothing could be further from the truth.  We call them hearing “aids” because  they aid us in hearing. They don’t give us normal hearing. They let us hear better than before when conditions are good.

Hearing aids are much like crutches. Crutches help a person with a “bum” leg get around, but they do not let that person run and jump and go rock climbing like a person with normal legs can.

When close to a person and in quiet situations, hearing aids can be wonderful in letting us hear. However, when the background sound levels increase, and when the distance increases, hearing aids become less and less useful, and finally, may make things worse than if we take them off. Hearing people need to realize this.

Furthermore, hearing aids typically only bring your hearing loss up to about half of what it was before. They do not restore your hearing back to normal. For example, I have an 80 dB loss. Hearing aids can bring my hearing up to about a 40 dB loss (a great improvement to be sure)—but not to 0 dB (normal). Thus the best hearing aids will never give me (or you) normal hearing.

Another aspect we haven’t mentioned yet is discrimination (now commonly called “Word Recognition”). Discrimination is how well you understand speech when it is at your ideal listening level. People with normal hearing typically have 100% discrimination. However, when we have hearing losses, typically our discrimination scores also drop.

For example, your discrimination scores may be 70%. This means that even under ideal conditions (when your hearing aids are fitted properly and you are in a quiet place and close to the speaker), 30% of what you hear will be pure gibberish.

Thus not only do you not have normal hearing—your hearing aids are only letting you hear 50% better—but you also hear a certain amount of gibberish at the same time. That is why you still need to speechread, have people close to you and facing you, etc.

Your family needs to understand all this. Then, hopefully, they will be more sympathetic to your plight, and will be more willing to accommodate your hearing needs.

Should you try hearing aids again? My advice, “Go for it”. Expect to hear better under good listening conditions. Just don’t expect miracles. Make sure your audiologist or dispenser will follow the above principles in fitting your hearing aids and not just say they know best and mess up (yet again). If they won’t follow the above principles, go to someone who will.