This is the third in a series of posts about hearing loss. In Hearing Loss Post 2, I talked a bit about the different levels of hearing loss. I have some hearing loss myself, so this is a subject that is important to me. This series is my contribution to raising hearing loss awareness. In this post, I want to explain a bit about the Speech Banana, and how it affects understanding conversation. As in the previous post, if you see something here that you know is inaccurate, please do not hesitate to let me know.
In general conversation, there are various sounds, called “speech sounds,” that a person makes when speaking, such as the b-l-o-g sounds in the word “blog”. If we look at an audiogram, we can place each of these sounds in a certain spot on the audiogram. For example, the “z” and “v” sounds are in a frequency between 250 and 500 Hz, and are generally made at around 30 decibels; “ch” and “h” are both made at about 1500 Hz, except the “h” sound is at 40 dB, whereas the “ch” sound is at 45 dB; and in the high frequencies around 6000 Hz is the “th” sound, generally made at 25 dB.
After the speech sounds are placed on an audiogram as I mentioned above, if you draw a round-ish shape around all of the speech sounds, it makes a shape similar to a banana. Therefore, the area where speech sounds are graphed is called the “Speech Banana” and is used to explain on the audiogram specifically which speech sounds people with hearing loss are and are not hearing during conversation.
(I think it may also be referring to when people are standing a certain distance away from one another, since I am, in fact, able to hear the sounds “z” and “v”. Mom and I tested it once, and we found that while I could hear the sounds just fine at close distances such as two or three feet, I could not hear the “z” and “v” sounds from 6 feet away whereas she could. However, I’m not sure if that’s it or not.)
Different people have different degrees of hearing loss in different frequencies. People with high frequency hearing loss will miss sounds that people with low frequency hearing loss hear perfectly fine, and vice versa. People with mild hearing loss will hear more sounds than those with moderate hearing loss, but they will still miss some. A person may have mild loss in one frequency, but moderate in another, and this affects what they do and do not hear. Not all hearing loss is the same.
Here’s an example: if Person X had a hearing loss all the way across the audiogram at 35 dB, he would be able to hear all the sounds that were below the line on the graph (meaning the sound is louder than 35 dB), but he would not be able to hear any of the sounds which appeared above the line on the graph (meaning the sound is quieter than 35 dB). Now, let’s apply this to the Speech Banana.
*Before I explain how this applies, I wanted to mention… I’ve noticed that a couple of the different Speech Bananas you can find on Google Images show a few differences on where the sounds appear on the audiogram. However, since this is just to give those reading my post a basic idea of how the Speech Banana works, I’ll just use the one that I originally clicked on, and not worry about it.*
According to the Speech Banana I’m using, there are about 5 sounds which are located above 35 dB. These sounds are: z, v, f, s, and th. That means that Person X is unable to hear those sounds, unless they are made closely and loudly enough. Then there are the sounds which are a little bit louder than 35 dB. These sounds are audible to Person X, but even so, are not nearly as clear to his hearing as they are to people who have normal hearing.
Now let’s think about how Person X’s hearing will affect his conversations. There are 5 different sounds that he is not hearing while he is listening to someone talk at a distance of more than a couple feet. Let’s look at a sentence, first as it looks normally, then as it looks without the sounds Person X is not hearing:
#1. Sentence A, normal hearing: “These are the days of Elijah, declaring the word of the Lord, and these are the days of Your servant Moses, righteousness being restored…” (first few lines of the song, “Days of Elijah”)
Sentence A, Person X’s hearing: “_e_e are _e day_ o_ Elijah, declaring _e word o_ _e Lord, and _e_e are _e day_ o_ Your _ervant Mo_e_, righteou_ne__ being re_tored…”
#2. Sentence B, normal hearing: “You are my sunshine, my only sunshine, you make me happy when skies are grey, you’ll never know dear how much I love you. Please don’t take my sunshine away.”
Sentence B, Person X’s hearing: “You are my _unshine, my only _unshine, you make me happy when _kie_ are grey, you’ll ne_er know dear how much I lo_e you. Plea_e don’t take my _unshine away.”
This is not, of course, an exact interpretation of how Person X hears all conversation and/or music lyrics. I think it’s possible (if he developed this loss and was not born with it) that his brain knows that the sounds are supposed to be there, and fills them in for him. However, he does not necessarily actually hear the sounds, and therefore it is more difficult and takes more time and effort for his brain to process speech. Now let’s meet Person Y.
Person Y has a hearing loss which is much more diverse than Person X’s. She hears some frequencies with a moderate hearing loss, some with a mild hearing loss, and some with normal hearing. Starting in the lower frequencies, Person Y hears at around 10 dB at 250 Hz, 30 dB at 500 Hz, 40 dB at 1000 Hz, 45 dB at 2000 Hz, 40 dB at 3000 Hz, and then her hearing is in the normal range from 4000 Hz up. Using the Speech Banana, we can see which speech sounds she might not hear in conversation.
Person Y’s hearing loss bypasses all of the speech sounds from 250-1000 Hz, so she can hear all of those with little trouble. It isn’t until after 1000 Hz that she starts to miss some. According to the Speech Banana I’m using for this post, Person Y cannot hear these speech sounds: p, h, g, and k. Let’s see the effect this has on the same sentences as before.
#3. Sentence A, Person Y’s hearing: “These are the days of Elijah, _re_aring the word of the Lord, and these are the days of your servant Moses, righteousness being restored…”
We see that this particular sentence is barely affected at all when Person Y hears it, whereas Person X will have much more trouble understanding it because of the sounds he’s missing. Though Person Y’s PTA, around 38 or so, is actually higher (worse) than Person X’s PTA, which is 35, Person Y can hear this particular sentence much better than Person X.
PTA stands for pure tone average; it’s where the audiologist takes the results of the audiogram at 500, 1000, and 2000 Hz and averages them. For example, my right ear’s audiogram reads 40 at 500 Hz, 40 at 1000 Hz, and 10 at 2000 Hz. When you average those numbers, my right ear has a pure tone average of 30.
Now let’s see what happens with the second sentence.
#4. Sentence B, Person Y’s hearing: “You are my sunshine, my only sunshine. You ma_e me ha__y when s_ies are _rey, you’ll never know dear how much I love you. _lease don’t ta_e my sunshine away.”
This sentence is affected more than Sentence A was, and in a different way than when Person X listened to it. While Person X had a few of the sounds cut out all throughout the song, Person Y heard most of the lines clearly until reaching “make me happy when skies are grey” at which point the sentence became garbled and confusing. This helps explain why some people with hearing loss are able to understand most of a sentence, but miss certain key parts because an important word contains a sound or two that they find difficult to hear.
Finally, just for fun, I’m going to write out Sentences A and B, omitting the sounds that I (according to the Speech Banana I’m using at the moment) should have difficulty hearing in my left ear. (I choose that one specifically because it’s my worse ear.) I am not sure how accurate this is, since I’ve always heard these song lyrics perfectly well and have never noticed a problem hearing the sound “s” or “z” in the songs, but this is just an idea of how it would sound as conversation from a certain distance, not necessarily exactly what I hear…
#5. Sentence A, supposedly my left ear’s hearing: “_e_e are _e day_ of Eli_ah, _re_aring _e word of _e Lord, and _e_e are _e day_ of Your _er_ant Mo_e_, righteou_ne__ being re_tored…”
#6. Sentence B, supposedly my left ear’s hearing: “You are my _unshine, my only _unshine, you make me happy when __ie_ are _rey, you’ll ne_er know dear, how much I lo_e you. _lea_e don’t ta_e my _unshine away.”
Like I said, although I will admit I have trouble hearing some sounds at a distance away, I do not quite agree that they are completely missing. Perhaps they’re quieter or something, but I can often hear them fine…as far as I know. I’ve never heard anything different, so maybe it’s just me…
Anyway, thank you for reading this post! Have an awesome day! God bless!
P.S. I tested the “Days Of Elijah” song at a medium volume in my left ear, and the sounds I was missing did, in fact, line up. It seems, though, that this does not apply to “You Are My Sunshine” for some reason.