The morning of Andrew’s NICU discharge, he failed two newborn hearing screenings: the Auditory Brainstem Response (ABR) and the Otoacoustic Emissions (OAE). As they are both basic screening tests, the NICU tests were completed on a pass/fail basis. Andrew failed both, in both ears.
The ABR measures the brain’s response to sound, while the OAE measures how sound travels through the ear’s various structures.
This week, Andrew had more extensive versions of each test.
The results of Andrew’s OAE test are remarkably normal. This is very good news. The results of Andrew’s ABR test, however, were pretty abnormal and indicative of moderate hearing loss. This is okay news. But, together, this is very bad news, and a hallmark for a condition called auditory neuropathy.
Auditory neuropathy is diagnosed when sounds enter through the ear normally (allowing one to pass the OAE), but the transmission of sound to the brain is impaired (thus the failed ABR). In other words, Andrew can hear. But he is unable to understand what he is hearing due to brain dysfunction.
Here are two simulations of what a person with auditory neuropathy would hear. This one is from Original to Profound. And this one is from Profound to Original. The study discussing the simulations can be found in an article by Zeng, Oba, Garde, Sininger, and Star (1999).
Unfortunately, treatment for auditory neuropathy seems to be minimal and conflicted. There are typically three approaches: (1) Do nothing. Just wait and see and hope for the best. (2) Try out hearing aids as a basic start–even though the ear’s structures have no problem transmitting sounds. (3) Try out the more extreme treatment of cochlear implants even though the inner ear usually works just fine. None of these options are particularly promising. Studies have shown that hearing aids and cochlear implants, for whatever reason, will help some individuals. But for the vast majority, it won’t.
We have just started to get the ball rolling in terms of paperwork to get Andrew fitted for hearing aids. Once that is done, Andrew will also begin receiving speech and hearing therapy from the New York State Early Intervention program.