in my last blog I discussed looking at hearing in each ear to make decisions about technology. Now I would like to talk about looking at speech perception in each ear to manage technology.
Why do we need two ears?
There is tons of research about the advantages of two ears. Two ears help when the signal is not clear – that is hearing speech at a distance and in noise. Soft speech is improved with two ears because the additional information heard from both sides makes speech louder. So, if that is the case, what do we need to do to be sure both ears are hearing well?
Checking speech perception in each ear
It is not enough to test speech perception binaurally. Binaural testing will give some useful information but it does not help you to understand how to repair any problems. We need to know how a child (or an adult for that matter) is performing with each ear separately to know what needs to be fixed. For example, a child could have one hear in which she hears fairly well with her hearing aids and the other ear hears very poorly. If we test binaurally than we have no way of knowing that this is the case. If we test each ear separately we will be able to see that one ear is performing poorly and may be able to improve the situation.
How can we fix problems??
If we learn that speech perception in one ear is significantly poorer than in the other, we are obligated to find out why.
- Is hearing in that ear poorer? If yes, what are we doing to change the technology so that both ear s are hearing at the same level?
- Are the hearing aids providing equal aided benefit in both ears? We CANNOT know this by doing real ear testing alone. Real ear testing will tell us what is reaching the eardrum but NOT what is reaching the brain. We need aided thresholds to tell us what is reaching the brain.
- When we do aided testing, do we get responses that are appropriate (at the top of the speech banana) throughout the frequency range?
- When we test speech perception, what kind of errors is the child making? Is he missing high frequencies in one ear (or in both)? If yes, is the technology providing enough high frequency information? If not, fix it.
If the technology is working, then what?
If the technology is providing sufficient auditory access than what do we do? Then it is a question of practice. We need to work to get both ears to hear well. When they do, binaural hearing will be optimal. So, this means that we need to work on listening skills in each ear separately. If a child is performing more poorly in one ear, he should spend a few hours a day (not during school), and most of the weekend, listening with the poorer ear alone. It will take some time, but skills can definitely improve resulting in improved binaural listening. Work with kids who get a 2nd cochlear implant after several years of listening with only one, has demonstrated that it is possible to improve listening skills in the later implanted ear but that to keep those skills up, they need some listening work in that ear on an ongoing basis. The results are worth it. Just Do It!!!