I frequently get questions from families asking about how to know if their child is hearing well enough with technology. Sometimes it is a concern that the child does not seem to be developing language quickly enough. Sometimes it is because the child does not turn to sound. Sometimes other concerns. My first questions is ALWAYS “What does the child hear with the technology.” Not every one can answer that question. RED FLAG.
I expect every parent, audiologist, speech-language pathologist, listening and spoken language specialist and others working with a child to know what the child hears, and, more importantly, what the child doesn’t hear.
First rule out technology problems
I am a firm believer in what Dr. Dan Ling said – “What they hear is what they say.” If a child cannot repeat words with “s” than I think he is likely not hearing “s”. If a child is confusing voiced and voiceless phonemes than I am concerned about low frequency hearing. So first, let’s look at technology.
What kind of test results do I want to see?
First, I want aided thresholds. I want to see if a child is hearing at a sufficiently soft level in each ear from low to high frequencies. I want to know that a child is hearing at the top of the speech banana in each ear. I want thresholds no worse than 20 dB. If a child hears well in one ear but not in the other then we know he is not hearing well enough.
If you don’t have aided test results, get them. You need the information. Without it we don’t know how to fix things. With the information, the audiologist can adjust the hearing aids or cochlear implants to try and improve perception.
The goal of all technology is to give children access to speech. We need to test speech perception to know how a child is hearing. Never assume. I want to see speech perception test results at normal conversation with right and left technology and with both ears together. Unless you test with each you do not have a full picture of what is happening. We hope that children will hear equally in each ear. But that doesn’t always happen. If a child is not hearing well in one ear it can effect binaural performance. If we know that perception is poorer in one ear we can plan therapy to improve perception in the poorer hearing ear which should result in improved perception with two ears.
We also need to test performance at soft speech (30-35 dBHL). If a child is not hearing at a sufficiently soft level, she will not be able to overhear conversation around her. That is critical since children learn about 90% of what they know by overhearing. They will not hear conversations on the playground, they will not hear children in the classroom responding to discussion questions.
We need to test performance in noise. The world is unfortunately a very noisy place. By testing how children are hearing in noise we will know what we have to do with technology to help them learn. If a child is having problems hearing in noise, we can make a good case for changing technology, adding FM at school and at home.
Scoring speech perception testing
There is no such thing as good enough for children with hearing loss (or for any children actually.) I want children to have good or excellent speech perception in all test conditions – normal conversational speech (50 dBHL); soft conversational speech (35 dBHL); and in competing noise (50 dBHL+5 SNR.)
Children with hearing loss should have their speech perception scored in the same way we score their typical hearing peers since they are in mainstream settings and have the same educational goals.
Excellent speech perception is 90-100 %. Good speech perception is 80-89%. Fair speech perception is 70-79% and poor speech perception is anything less than 70 %. If scores are not good enough, step one is to try and improve technology settings to improve hearing. If that has been done, than auditory based therapy needs to be planned to improve skills.
Real ear measurements are just the start
Real ear measurements are a critical starting place when setting technology but we really need to remember that they are just a start. They are an average and work well for a lot of patients but NOT FOR ALL. We need to begin by being sure that technology settings meet target gains. Then we have to test.
Aided thresholds and speech perception will tell us if the child is hearing well enough. If not, it doesn’t matter if the child’s technology is meeting targets. If the child isn’t hearing well we need to adjust technology settings.
GOOD ENOUGH IS NEVER ENOUGH