Mapping a Cochlear Implant

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Although this article is directed at parents of children who have CIs, I thought this information would be especially helpful to those of you who have upcoming surgeries, activations or are new CI users:

Mapping a Cochlear Implant - Hearing Pocket

Mapping the Cochlear Implant
A Parent's Guide to Understanding a Cochlear Implant Programming
Nicole C. Sislian, MA, CCC/A
One of the routine events in the life of a Cochlear Implant child is the many visits to their cochlear implant center to reprogram the implant – or to get a new Map set. What is a Mapping, and what information should parents come away with that would help them in the overall development of their child? Nicole Sislian, supervisory audiologist at the New York Eye & Ear/Beth Israel Cochlear Implant Center, gives us a detailed explanation of the MAP and what it accomplishes.

The Need for a MAP

Reprogramming of the cochlear implant, or what is commonly called a “MAP”, refers to the setting of the electrical stimulation limits necessary for the cochlear implant user to perceive soft and comfortably loud sound. Normal acoustic hearing can process sounds within a 120dB range. Normal speech ranges anywhere between 40 and 60dB (the shaded area of this audiogram). Cochlear implant recipients have a dynamic range of only 6-15dB in electrical current. Therefore, in cochlear implant speech processors, a 120dB acoustic range must be compressed into an electric range of 6-15dB.

Due to the small electrical range that a cochlear implant is limited to, CI users are more sensitive to loudness changes, and loudness growth differs from those with ordinary hearing. Cochlear implant processors must compress acoustic amplitudes (i.e. the range of all the different levels of sound) into this small range. These stimulation levels correspond to psychophysical (i.e. sensory responses to outside stimuli) measurements known as Threshold (T) and Comfort (C or M) Levels. During the mapping process, the threshold and comfort levels of each individual electrode on the cochlear implant’s internal electrode array that is located inside the ear are adjusted in order for the user to hear a wide range of sounds in ‘everyday life’ (soft to loud).

Threshold levels are set to allow the user access to soft speech and environmental sound. Comfort Levels refers to the amount of electrical current a user needs for perception of a comfortably loud ‘beeping’ signal. These measurements are downloaded into the speech processor, and then incorporated into a coding strategy, which the processor uses to send the electric signals to the internal implant in an organized manner. The processor will not allow the signals entering it to exceed these set parameters.

Updating the MAP
A cochlear implant user needs to have their MAP frequently updated. This is because each MAP is individual to its user and is constantly changing. Over time, MAPs may become weak, softer, or less clear. This is the result of several factors including adaptation and tissue growth. Fibrous tissue continues to grow over the internally implanted device (electrodes and receiver) during the months following surgery. These changes may change the amount of electrical stimulation needed to stabilize the signal. The greater the tissue growth over the implant device, the more power is required to stimulate it. If tissue growth occurs without mapping, the signal will begin to fade.

Also, when the MAPs are new, they tend to sound louder. With experience, the user becomes accustomed to the stimulation and ‘adapts’ to it, finding that over time, it may no longer be a loud enough signal. This is called adaptation. This is similar to when one listens to music at a set volume level for a long period of time. It sounds comfortably loud at first, but as the minutes pass we find ourselves raising the volume. Reprogramming the speech processor compensates for any changes that occur due to adaptation.

How a MAP is Performed
Threshold measurements may be obtained in several ways, depending the age or functioning level of the patient. For adults and children over age six, a hand raising method is used to determine T-Levels (similar to a hearing test). This is done by having the child trained to raise their hand in response to hearing a sound until the threshold is reached. Typically, one audiologist is used. Electrical stimulation is reduced until the user detects a sound 100% of the time.

For children under three years of age, the Visual Response Audiometry (VRA) method is used. The child is trained to look at a moving toy in response to sound. The stimulation is then reduced until the lowest level that the child is able to detect the sound. Typically, two audiologists are used; one training the child and one manipulating the computer controls.

Play audiometry is used for children three years to six years old. The child holds a block or other toy in their hand, usually at the ear of the side that is being MAPed, and is trained to place it into the box when they perceive the sound. The stimulation is reduced to the lowest detectable level. Again, two audiologists are used.

Comfort level measurements may also be obtained in several ways, depending the age or functioning level of the patient. For adults, a loudness scaling chart (giving a sound a value from one to ten) or verbal response is used to determine Comfort Levels. For children over the age of five, this method may also be used. For children under age five, the comfort levels may have to be estimated, using the threshold levels or objective measures (see below) as a reference.

Objective methods are when the audiologist monitors the brain’s response to sound input, such as Neural Response Monitoring or Electrically Evoked Stapedial Reflexes. These methods allow the audiologist to set threshold and comfort levels without patient input.

After every MAP, the user is asked to repeat various speech sounds and words. The MAP may be altered for sounds that are missed or confused.

Additional Tests
In addition to regular MAPs, the cochlear implant patient must also be periodically evaluated. A soundfield audiogram and speech perception performance must be tested using the implant in the sound booth. These results assist in the MAPing process. Any speech frequency tested which is not being perceived within the typical hearing range may be boosted during the mapping. These tests are done less frequently than a MAP, typically twice a year. Younger children and those recently implanted may have these tests performed more often.

MAP Reports
The mapping report provides printed out information on map parameters, threshold and comfort level settings. It is not essential for parents to understand the information contained in this report. It is merely a print-out of the settings created during the mapping session. It should be used only be used as a reference for the mapping audiologist.

What may be helpful to the parent is a report of what is in each program slot. The parents should be given clear instructions from the audiologist performing the MAP on the following: a schedule of when or whether to change the programs; which programs may be designated for an FM System; which may be a back-up program or an old program; which may be a noise program, etc.

Review
The MAP procedure is programming the speech processor so that the normal acoustic dynamic range may be compressed into the small electrical range of the cochlear implant device. When a MAP is performed efficiently, the user will have hearing within a normal to near-normal range. Parents should use the mapping sessions to discuss their child’s progress at home, school, and in therapy. Questions and problem issues may also be addressed. The audiologist will give recommendations on if and when to change programs as well as when a follow-up appointment should be made.

Nicole Sislian, M.S. is the Supervisory Audiologist at the NY Eye & Ear / Beth Israel Cochlear Implant Center in New York City. She performs MAPs and Auditory Evaluations on children with cochlear implants.
 
Good info! Thanks for sharing it cuz it helps me understand what goes on with the students who have CIs. :)

Just found out that we will be getting around 25 new students and 22 of them have CIs ranging from preK to 8th grade. Wow!!!!! Will be an interesting year for the 2007-08 school year.
 
Shel,

I'm glad you and R2D2 found the information helpful! :)

22 students with CIs? That's great!!

I've been told that there are more students entering my university's D/HH program with CIs. Including myself, we are up from 2 students to 6. :)
 
Shel,

I'm glad you and R2D2 found the information helpful! :)

22 students with CIs? That's great!!

I've been told that there are more students entering my university's D/HH program with CIs. Including myself, we are up from 2 students to 6. :)

I am wary of it cuz usually the students who have CIS that we get are the ones who didnt benefit from their CIs. That number makes me nervous cuz are we getting older children who have fallen so far behind in academics due to not being properly served in the mainstreamed programs? I dont know if u read it but there was another thread about a student with a CI who had to fight with the school district in getting a CART instead of a sign language interpretor..this is a perfect example of why we get students referred to our schools cuz of the public schools not willing to provide accodomations to meet their needs and they suffer and then it is up to us to help them catch up which is a DIFFICULT task to do! Our schools provides EVERYTHING to meet their needs so I dont understand why not send them to deaf schools in the first place ..heck we have spoken English added to meet the needs of the CI students but the public schools find ways to minimize meeting those needs. It doesnt make sense.
 
Shel,

Yes, I did read that thread. :( Was that person's situation ever resolved?

I hate to hear scenarios like the one you describe. It only makes your job as an instructor that much more difficult and even more frustrating for the children you work with. :(

One of the problems is that people think CIs automatically make a child hearing. The truth is, they don't. I've always been of the opinion that an implanted child should receive instruction (i.e. language development, academics) using TC so that if they aren't benefitting from their CI, they still have sign as a backup to communication.
 
Hi Shel,

So who decides to send the children on to your school? The public school?

It sounds to me as if you should be talking to the policy makers in your particular district about what's going on in terms of their policy. Are these children expected to cope with no support in their mainstream school and then are only sent to your school when this is not working? Doesn't sound good to me.

They should either be fully supported in their mainstream environments or go to your school in the first instance.
 
One of the problems is that people think CIs automatically make a child hearing. The truth is, they don't. I've always been of the opinion that an implanted child should receive instruction (i.e. language development, academics) using TC so that if they aren't benefitting from their CI, they still have sign as a backup to communication.

I agree with you.
 
Hi Shel,

So who decides to send the children on to your school? The public school?

It sounds to me as if you should be talking to the policy makers in your particular district about what's going on in terms of their policy. Are these children expected to cope with no support in their mainstream school and then are only sent to your school when this is not working? Doesn't sound good to me.

They should either be fully supported in their mainstream environments or go to your school in the first instance.

The parents decide this..The counties will fight to keep them in their schools even though they arent doing well due to MONEY!!! It is the parents that finally recognize that they arent benefitting in the public schools that they make the decision...it is so stupid when politics become a part of the decision making process...I dont get it...
 
Due to the small electrical range that a cochlear implant is limited to, CI users are more sensitive to loudness changes, and loudness growth differs from those with ordinary hearing. Cochlear implant processors must compress acoustic amplitudes (i.e. the range of all the different levels of sound) into this small range. These stimulation levels correspond to psychophysical (i.e. sensory responses to outside stimuli) measurements known as Threshold (T) and Comfort (C or M) Levels.

I read that HiRes has a much wider dynamic range and loudness changes are more smooth.

Can anyone tell me if HiRes really makes sounds more "full" and more "smooth" in terms of volume changes compared to CIS? What I read is that many HiRes users reported that the volume is actually much more "quieter" yet their comprehension of speech is improved. That seems odd and counterintuitive to me!
 
The parents decide this..The counties will fight to keep them in their schools even though they arent doing well due to MONEY!!! It is the parents that finally recognize that they arent benefitting in the public schools that they make the decision...it is so stupid when politics become a part of the decision making process...I dont get it...

Ohhh okay! That's pretty bad isn't it? You'd think that support within the public school for any child with special needs was mandated in law in the US. I remember growing up, we used to look to US with envy because it seemed that they looked after their deaf people really well.

On the other hand, maybe also the parents are hearing more about the reputation of your school and are curious about the bibi approach?
 
Ohhh okay! That's pretty bad isn't it? You'd think that support within the public school for any child with special needs was mandated in law in the US. I remember growing up, we used to look to US with envy because it seemed that they looked after their deaf people really well.

On the other hand, maybe also the parents are hearing more about the reputation of your school and are curious about the bibi approach?

I have NO idea...everything is just becoming so more complicated these days..it is frustrating..maybe cuz of the NCLB law (No Child Left Behind Act) ...:pissed: to Bush!!! Nothing makes sense anymore these days now. Bush needs to be THROW!!! ( IN asl ) :)
 
Very informative article - I'll be going to get my CI re-mapped soon.
 
I dont know if u read it but there was another thread about a student with a CI who had to fight with the school district in getting a CART instead of a sign language interpretor..this is a perfect example of why we get students referred to our schools cuz of the public schools not willing to provide accodomations to meet their needs.

Actually Shel this is par for the course in public schools. Many like to lump the kids with disablities into their own little groups and treat them all the same. It'll take alot more parents to fight the system to get any changes. Some like us decide to say screw you and go elsewhere for better programs. I do admire those who continue to push for the services their kids need tho.

As for those who don't get served well, it's probably because their parents placed their trust in the 'educated' people. Unfortunately it's the adminstrations job to keep costs down so they say no to alot of things, a parent really does need to know the laws and be willing to not back down. We made the mistake when our daugther with DS was preschool age of actually thinking that the teacher really cared about her and would help us work toward her achieving as much independence as possible. We became very disablusioned (sp?) by the time she as 5 I think. THen the big 'fights' with the staff and administration began. There were good years and bad years. When she was going to enter jr. high we moved her to the states school for the deaf.

While I can't say that things are always great they program is actually very good for her. and she does now have friends. :) She still is 'excluded' by many in that school tho. What I mean by that is many staff will not go out of their way to come up with ideas or ways to include her in their activities, they expect her aide to do all the hard work of keeping her busy etc. that goes for most of the kids with MR or other significant problems to,
 
I have NO idea...everything is just becoming so more complicated these days..it is frustrating..maybe cuz of the NCLB law (No Child Left Behind Act) ...:pissed: to Bush!!! Nothing makes sense anymore these days now. Bush needs to be THROW!!! ( IN asl ) :)

Well when complaining about NCLB why not include Sen. Chappaqudic...oh sorry Kennady. DOn't worry Bush will be gone in a year or so and things won't change. I'd say throw bush out just because he won't enforce our immigration laws...but that's another story. As for NCLB, if kids aren't learning the basics needed, you know like math computation to include beginning algebra and how to write a sentence etc. then something needs to change, and the tests are slowly changing some of that.

To put math into perspective as to how it's taught here and in another country. I have a co worker who immigrated legally from Mexico and is now a citizen. She has a son who is in hmm, 6th grade. She's been really frustrated at the attitude of teachers here in the US about teaching math concepts. In fact she told his teacher that if he was in Mexico he'd still be in 3rd grade with his current math skills. She's frustrated that they haven't flunked him and just keep passing him along to the next grade when he doesn't have the concepts down. Those who attend school in Mexico only go for 1/2 day and then many go and work at jobs for 1/2 days. Some of course drop out and just work. Anyway it would have been nice to have seen the shock on that teachers face when she told him that Mexico might be poor but they do expect you to learn the facts before they'll move you to the next grade. :) :)

If so many schools are having to teach to the test (which is basic skills) then perhaps it's time for the schools to really look at how successful their curriculum is. Personally 'new' math sucks big time. Memorization is really a required skill in math and needs to be learned before moving on to more complex computations. And that's just the math part. My oldest graduated over 10 yrs ago and even then they were not stressing sentence structure so really the curriculum needs to go back to what it was. (by that I mean they did not spend much if any time diagramming sentences and stuff like that, you should have read the oldests final english term paper, ugh. and she got an A, probably for effort, lol)

btw, cloggy has a much better concept of sentence structure then more the 1/2 the students in the reading and writing critically class I took in college 2 yrs ago. And those students were recent graduates who had had to pass the 'test'. sigh.
 
Hi Shel,

So who decides to send the children on to your school? The public school?

It sounds to me as if you should be talking to the policy makers in your particular district about what's going on in terms of their policy. Are these children expected to cope with no support in their mainstream school and then are only sent to your school when this is not working? Doesn't sound good to me.

They should either be fully supported in their mainstream environments or go to your school in the first instance.

Hi R2
As a parent of a child who has had sped services since birth (for down syndrome) I can answer your question. Parents are part of the IEP team and make the decision as to where and how their children will be educated. Many have pushed for programs or services in their home districts. The success of these programs varies greatly from district to district.

My district was small and actually didn't have the programs, perhaps we made a mistake in keeping our child there until middle school, but we really can't blame the school itself...except for having staff who could talk good but didn't follow through. This type of programming can work but it's requires parents who ride the a-- of the people who are supposed to be following the agreed upon IEP.

Having said that, the school district itself will work very hard at telling parents that they don't know the laws. Even if a district would agree to get a ASL interpeter for a child that in no way translates into actually getting a good one, especially in rural areas. So a child who has parents who don't understand the laws (beyond knowing that their child has the right to an education in his LRE) and trust the so called 'experts' (staff) are very easilly run over and not given the supports they really need to be successful in their home school.
 
Hi R2
As a parent of a child who has had sped services since birth (for down syndrome) I can answer your question. Parents are part of the IEP team and make the decision as to where and how their children will be educated. Many have pushed for programs or services in their home districts. The success of these programs varies greatly from district to district.

Thanks for the explanation, Jag. It sounds like promises and the reality of support is very different and variable according the the district you live in.

I think this makes the situation when arguing about the efficacy of CIs or oral vs sign a lot more complicated because we just don't know how much support that child has been getting in their local educational areas.

One of the important factors determining outcome apart from parental involvement concerns the quality of the educational program. If it's poor quality, whether oral or sign, then it will yield poor quality results.
 
Well when complaining about NCLB why not include Sen. Chappaqudic...oh sorry Kennady. DOn't worry Bush will be gone in a year or so and things won't change. I'd say throw bush out just because he won't enforce our immigration laws...but that's another story. As for NCLB, if kids aren't learning the basics needed, you know like math computation to include beginning algebra and how to write a sentence etc. then something needs to change, and the tests are slowly changing some of that.

To put math into perspective as to how it's taught here and in another country. I have a co worker who immigrated legally from Mexico and is now a citizen. She has a son who is in hmm, 6th grade. She's been really frustrated at the attitude of teachers here in the US about teaching math concepts. In fact she told his teacher that if he was in Mexico he'd still be in 3rd grade with his current math skills. She's frustrated that they haven't flunked him and just keep passing him along to the next grade when he doesn't have the concepts down. Those who attend school in Mexico only go for 1/2 day and then many go and work at jobs for 1/2 days. Some of course drop out and just work. Anyway it would have been nice to have seen the shock on that teachers face when she told him that Mexico might be poor but they do expect you to learn the facts before they'll move you to the next grade. :) :)

If so many schools are having to teach to the test (which is basic skills) then perhaps it's time for the schools to really look at how successful their curriculum is. Personally 'new' math sucks big time. Memorization is really a required skill in math and needs to be learned before moving on to more complex computations. And that's just the math part. My oldest graduated over 10 yrs ago and even then they were not stressing sentence structure so really the curriculum needs to go back to what it was. (by that I mean they did not spend much if any time diagramming sentences and stuff like that, you should have read the oldests final english term paper, ugh. and she got an A, probably for effort, lol)

btw, cloggy has a much better concept of sentence structure then more the 1/2 the students in the reading and writing critically class I took in college 2 yrs ago. And those students were recent graduates who had had to pass the 'test'. sigh.

Good post!!!

You hit the nail on the head about education. There is too much of a vested interest in "flipping" kids from one grade to the next whether or not they have mastery of said skills and knowledge of a given grade. This was happening long before NCLB came about. Does anybody remember the disaster when the system deemphasized Phonics? Don't even get me started with Ebonics. The system has been screwing around probably since the sixties (surprise! surprise!) trying to come up with all kinds of newfangled ways to educate children. What needs to be done is to stick with what works and enhance the materials for those who have trouble with the standardized stuff. It doesn't have to be complicated...it really doesn't.
 
I graduated high school in 1989.

While my education was by no means perfect, I learned the basics of reading, writing, history and science. (I was also taught to read using Phonics.)

By the time I reached junior high, I was fortunate enough to have a 7th grade English teacher who would not hesitate to turn an "A" paper into an "F" if "t's" were not crossed and "i's" were not dotted. I really hated her at the time, but when I look back, I'm very thankful for what she taught me. Interestingly enough, this was the same teacher who expressed surprise after learning that I qualified for the district level spelling bee. (I remember her telling me, "I didn't think you would win because Julie is the best speller in class." Instead of being insulted, her comment inspired me to work even harder.)

The following year I had a wonderful English teacher who encouraged me to write. Even though I had no interest in writing, she encouraged me and helped develop the love I have for writing today.

Until I met this English teacher, I didn't care about school and received average grades.

By the time I was in high school, I took several Honors courses and put 100% effort into my work.

In high school I was also fortunate enough to have an English teacher and the advisor of our high school newspaper (a published author) further encourage my writing persuits.

When I entered college, one of my professors asked me if I was an English major. When I said no, she told me I should consider it. Her question made me feel good and reminded me of how thankful I was for a 7th grade English teacher who cared enough to push me beyond my limits so I could become a competent (for the most part anyways :)) writer.

I don't write this post to brag -- only to say that teachers need to play a strong role in their students' education.

As sr171soars pointed out, teachers also need to develop basic skills which will enable their students to succeed. I heard of a university TA who gave students a "D" on their term paper if they included slang in their writing. (If I were in that TA's position, I would have given them an "F.") Too many teachers (although not all) today let their students slip through the cracks which only hurts them in the long run.
 
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