October 30, 2013
TreaOften we see patients with hearing loss who refer to themselves as “deaf”. Spouses may also chime in, “See, I told you you were deaf”. While we do not downplay the effects of hearing loss, we always gently correct the speaker when it is not used correctly. Mild or moderate hearing impairment and deafness are no more synonymous than near-sightedness and blindness. The distinctions between hearing loss vs deafness are important and bear an explanation.
In typical audiological use “hearing loss” is just that. It is a reduction of the sense of hearing, regardless of degree, from a previous level. Most people who are hard of hearing are “hearing people” who have (gradually or suddenly) experienced more difficulty using their ears to communicate. This may be due to genetic conditions, ear malformations, disease, medications, noise abuse, trauma, aging or a combination of factors. This can be a devastating condition for patients who have always relied on hearing as their primary mode of communication. These people find themselves relying on strategies such as lip-reading, using captioning and using amplification, in order to maximize whatever hearing they retain. This describes many hearing aid wearers. They are able to hear, but their damaged ears require increased intensity of sound, and they often hear very well with amplification. Often certain sounds can be heard reasonably well (typically low frequency “bass” sounds) while higher-pitched sounds are impaired. Unfortunately English and many other languages emphasize high-frequency sounds for clarity.
On occasions where there is essentially a total lack of hearing (over 90 decibels is required for the person to detect a sound), we use the term “deaf”. At this level of hearing impairment one cannot generally use sound as a primary mode of communication, given the acoustic complexity of spoken language, particularly if the condition is longstanding. Many people are born deaf and have never actually “lost” hearing. Communication via a signed visual language, such as American Sign Language (ASL), Signed Exact English or finger spelling, becomes a primary method with an added benefit that it is mutually accessible to hearing people. Deaf people also utilize facial expressions and other non-verbal cues to add emphasis to a greater degree than hearing people. These methods work perfectly well along with written language and visual alerts, and deaf people may arguably be considered less “handicapped” than hearing-impaired people who have lost the sounds they relied on so heavily.
Treatment decisions are often based on the distinctions of hearing loss vs deafness. When a deaf person wishes to hear (many prefer to maintain their deafness), often even the most powerful hearing aids are inadequate for listening effectively to speech. Many deaf people wear hearing aids primarily to hear environmental sounds or elements of music. Often patients who have been deafened after learning language will use a cochlear implant (CI). This device converts acoustic signals into electrical impulses that stimulate the auditory nerve directly. The nerve fibers project to the same auditory brain region as in hearing people. While many report the sound can be “mechanical” or “metallic” and harsh at first, auditory memory and experience enable many patients to hear at near-normal levels.