Perhaps this sounds familiar: you misunderstand conversations, or your family complains that you don’t hear them well. Maybe you had your hearing checked and your results showed that your hearing is “within normal limits.” If you left your appointment a little confused, you are not alone. In fact, you may have a condition known as hidden hearing loss.
What is hidden hearing loss?
Hidden hearing loss is when an individual’s audiogram reflects normal hearing sensitivity at all frequencies (pitches), but speech-in-noise testing reflects a deficit. This can occur in people when they have been repeatedly exposed to loud volumes of noise, such as sporting events and concerts. Typical hearing loss occurs when there has been damage to the hair cells of the inner ear. With hidden hearing loss, those hair cells are intact (which is why the audiogram reflects normal hearing), but the auditory nerve fibers have been damaged. The nerve fibers are responsible for sending the signal from the inner ear to the brain. In this situation, the connection has been compromised, therefore affecting the message to the brain. (For more information, see how hearing works.)
How do you check for hidden hearing loss?
First, a normal hearing exam is completed. If everything checks out as “within normal limits,” a speech-in-noise test will be completed. There are several different tests which assess the individual’s ability to understand and repeat back sentences amidst varying levels of background noise. If a deficit arises during this testing, it can be concluded that there is something going on deeper than the audiogram can assess.
Another way to diagnose hidden hearing loss is by an Auditory Brainstem Response test (ABR)1. This assessment involves placing electrodes on the head and headphones in the ears to measure the auditory nerve’s response to sound. The nerve is more heavily involved with this form of testing, which is why hidden hearing loss is more likely to be uncovered with this exam.
Hidden hearing loss and auditory processing disorder
Hidden hearing loss occurs when there has been damage to the nerve fibers (typically from noise exposure) causing a difficulty with speech understanding, especially against background noise.
An auditory processing disorder is when there is a disconnect between what the brain is doing compared to what is being heard. This deficit occurs at the central auditory system, while hidden hearing loss is due to an issue with the peripheral auditory system.
Treating hidden hearing loss
Currently, using hearing aids is the only treatment for hidden hearing loss. Low-gain hearing aids with ample noise reduction have been shown to improve patient outcomes with speech understanding tasks. Future therapies are being researched.
Concerned about hidden hearing loss?
The professionals at HearingLife would be happy to discuss any concerns you may have regarding hearing loss. Get started by scheduling an appointment online now for a complimentary hearing assessment* at a location near you.