Dynamic Range of CI?

L

Lissa

Active Member
Premium Member
Joined
Dec 29, 2007
Messages
4,354
Reaction score
0
A person asked me this question about my cochlear implant, they were not helpful to explain what it is, but I am interested to know what it is. Would somebody please explain what this is and how to find out my dynamic range
 
DeafLissa90 said:
A person asked me this question about my cochlear implant, they were not helpful to explain what it is, but I am interested to know what it is. Would somebody please explain what this is and how to find out my dynamic range
Click to expand...

The maxium available for AB is 80db. Each person is different. It depends on your MAP and your thresholds. Your audiologist could tell you.
 
Freedom has smallest DR I think about 50db or so, Will ask SLT this afternoon.

AB 80db (although I found one info stating 95db)
MED-EL 75db
 
Correct me if I'm wrong but my thoughts from my reading of different studies and articles and web sites having a high DR is not always better. Speech range is 50 DR if I read it correctly.
DR or Dynamic Range is controlled by the processor and the software on that Processor.

Just wanted to know if I was getting this correctly.


(Digital Signal Processing for Hearing Aids, Bluetooth Headsets, Mobile Phones | DSP, ScienceDirect - Hearing Research : Noise improves suprathreshold discrimination in cochlear-implant listeners, http://www.nidcd.nih.gov/staticresources/funding/programs/npp/pdf/archived/N01-DC-9-2100QPR09.pdf)
 
I asked a question to one of Engineer of COchlear in New South Wales, Austrailia. My question was, what's the cochlear dynamic range (aware of AB's and Med-El) also asked him to explain the properties of DR's Job...

His answer were....To answer your question on the dynamic range, dynamic range in the context of a cochlear implant refers to the loudest level of sound that your speech processor can pick up and allow you to hear. Now normal spoken speech is around 30db and lower. If your speech processor were to pick this speech up and then instruct the implant to stimulate your cochlear with the same power level then that could cause considerable damage to your cochlear and also possibly cause you discomfort and pain. So the job of the entire cochlear system to is to pick up the sounds of everyday life, map them to a lower sound level before stimulating your cochlear because your cochlear does not need a lot of power for it to perceive sound so for example, a 35 db sound from your surrounding could be picked up by your speech processor, reduced down to say 2 db before your cochlear is stimulated. Now each patient has a different dynamic range depending on pain thresholds i.e. the maximum level of stimulation before they experience discomfort. So say if your audiologist determines that any stimulation above a 5dB level will cause your pain or discomfort, then that 5dB becomes your dynamic range which means that your cochlear system's job from then on will be to pick up sounds from everyday world and process them in such a way that they could all be fitted to within the 5db range and nothing more. So the dynamic range when referring to a patient's dynamic range refers to the maximum sound level or power level a person's cochlear can withstand. The dynamic range of the speech processor however refers to the maximum sound level your speech processor can pick up and allow you to perceive. So if the dynamic range of your speech processor is 70dB then that 70dB will be the maximum sound level that you would be able to perceive to your surroudings. ANd finally to put everything into perspective, consider a situation where a patient's dynamic range is 5dB and the dynamic range of the speech processor is 70dB, now say the patient comes across a 70dB sound, their speech processor will then pick that sound up, reduce it to around 5dB and stimulate their cochlear with this level. If the patient were to then come across an 80dB sound, they would not be able to perceive that sound level, they would however only perceive 70dBs because any sound level above 70dBs would get clipped down to 70dB i.e. 70dBs would be the maximum you'd be able to perceive. As far as to what your dynamic range is, your audiologist might be able to answer that better than me :). Hope that helped you :). Take care
 
overthepond said:
I asked a question to one of Engineer of COchlear in New South Wales, Austrailia. My question was, what's the cochlear dynamic range (aware of AB's and Med-El) also asked him to explain the properties of DR's Job...

His answer were....To answer your question on the dynamic range, dynamic range in the context of a cochlear implant refers to the loudest level of sound that your speech processor can pick up and allow you to hear. Now normal spoken speech is around 30db and lower. If your speech processor were to pick this speech up and then instruct the implant to stimulate your cochlear with the same power level then that could cause considerable damage to your cochlear and also possibly cause you discomfort and pain. So the job of the entire cochlear system to is to pick up the sounds of everyday life, map them to a lower sound level before stimulating your cochlear because your cochlear does not need a lot of power for it to perceive sound so for example, a 35 db sound from your surrounding could be picked up by your speech processor, reduced down to say 2 db before your cochlear is stimulated. Now each patient has a different dynamic range depending on pain thresholds i.e. the maximum level of stimulation before they experience discomfort. So say if your audiologist determines that any stimulation above a 5dB level will cause your pain or discomfort, then that 5dB becomes your dynamic range which means that your cochlear system's job from then on will be to pick up sounds from everyday world and process them in such a way that they could all be fitted to within the 5db range and nothing more. So the dynamic range when referring to a patient's dynamic range refers to the maximum sound level or power level a person's cochlear can withstand. The dynamic range of the speech processor however refers to the maximum sound level your speech processor can pick up and allow you to perceive. So if the dynamic range of your speech processor is 70dB then that 70dB will be the maximum sound level that you would be able to perceive to your surroudings. ANd finally to put everything into perspective, consider a situation where a patient's dynamic range is 5dB and the dynamic range of the speech processor is 70dB, now say the patient comes across a 70dB sound, their speech processor will then pick that sound up, reduce it to around 5dB and stimulate their cochlear with this level. If the patient were to then come across an 80dB sound, they would not be able to perceive that sound level, they would however only perceive 70dBs because any sound level above 70dBs would get clipped down to 70dB i.e. 70dBs would be the maximum you'd be able to perceive. As far as to what your dynamic range is, your audiologist might be able to answer that better than me :). Hope that helped you :). Take care
Click to expand...

That explains the sound "capping" effect when I hear a loud sound (siren, concert, jet, etc.). These sounds although loud, will not be perceived at its correct loudness. I've heard it up to the perception of loud speech threshold, though I'm glad it has this limitation as I wouldn't have to be concerned about damaging my CI hearing. Good insight to know more about our CIs, thanks Overthepond.
 
Excellent explanation Overthepond!!!

That puts the whole context of dynamic range in perspective.

SCBassist - Yeah, I noticed that when a tea kettle whistles up the frequency levels. I'll hear the whistle for a little bit and then it is gone. I will probably discuss this with my audi to increase my dynamic range. I can tolerate louder noises as it is.
 
Back
Top