What Makes for Success?
We know that there are lots of many things which contribute to success for children with hearing loss. To name a few of the things we know:
- Early identification
- Early and appropriately fit technology
- Language stimulation provided by parents
- Academic level of family
- Socioeconomic status
- Access to auditory based therapy
- Other disabilities
Some are within the control of families, but others are not within their control. Families cannot control socioeconomic status or how many years of schooling they have had but they do not need to let those things become primary factors. Families from lower socioeconomic status enrolled in listening and spoken language programs working with good clinicians can learn to be outstanding providers of language stimulation. (I know many who have.)
Determining Which Factors are Important for Success
There is a lot of research that has demonstrated the advantages of early amplification and early intervention. Although there are differences of opinion, most people believe that the earlier the better when it comes to technology.
Is there a difference between in performance between hearing aids and cochlear implants? Obviously, cochlear implants are for children with severe and profound hearing loss only, and children with mild to moderately severe hearing loss use hearing aids. Children with severe hearing loss may use either hearing aids or cochlear implants but more and more children with severe hearing loss are moving toward cochlear implants.
There are several differences between hearing aids and cochlear implants. Children with cochlear implants have more severe hearing loss than those with hearing aids. Data indicates that children who wear cochlear implants wear them more hours/day than children with hearing aids. This may be because children who wear hearing aids, because of the less severe hearing loss, may some things without hearing aids so they may be more comfortable going without them. In addition, degree of audibility varies, with cochlear implants often providing more audibility that hearing aids.
Outcomes of Children with Hearing Loss Study
A multicenter study (Outcomes of Children with Hearing Loss) Outcomes study looked at performance with hearing aids over a five year period. As part of their research they looked at aided benefit with hearing aids, surveys of parents, and reviewing data logging information when it was available. Overall, they found that children with better audibility had better outcomes. It is great to have it verified. They recommended that fitting as close as possible to prescriptive targets can increase audibility. (I want to point out that real ear measures only measure sound reaching the tympanic membrane. So in addition to prescriptive measures, behavioral testing, which measures the entire auditory system, should be included in evaluations.)
The Role of Audiologists
If better audibility results in better performance, audiologists are the people who can make all the difference in the world. Audiologists are the ones who fit and monitor technology. Audiologists need to monitor technology on a regular basis, they need to be certain that kids are hearing at the top of the speech banana (at the speech string bean), and they need to assure that there is limited distortion. By doing so, they can provide the necessary audibility to children with hearing loss, and, as a result, better chances for improved function.
Audibility is the key to the beginning of understanding. If a sound is not audible, then understanding the sound’s importance is not possible.
Audibility is thus the key to success in hearing aid fittings. But, because of communication problems when working with hearing impaired children, audibility for certain frequency ranges is not always easy to determine. Fortunately, the clinician now has an objective tool to determine audibility for those patients who are not easy to communicate with. The National Acoustics Laboratory of Australia has developed the HEARLab, which measures cortical activity of a person subjected to calibrated sounds in sound field, both aided and unaided.