Audiology: Hearing Loss
Hearing loss can be classified into the following categories:
- Slight/Minimal Hearing loss (16 to 25 dB HL)
- Mild Hearing Loss (26 to 40 dB HL)
- Moderate Hearing Loss (41 to 55 dB HL)
- Mod.-Severe Hearing Loss (56 to 70 dB HL)
- Severe Hearing Loss (71 to 90 dB HL)
- Profound Hearing Loss (91 dB HL and above)
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Untreated Hearing Loss:Hearing loss isn’t just an ear issue; it’s a quality of life and health issue. Untreated hearing loss can have serious emotional and social consequences. A decrease in hearing sensitivity is associated with diminished cognitive function, poorer mental health, and social withdrawal. A nationwide survey of 4,000 adults with hearing loss compiled by the National Council on Aging (Kochkin & Rogin, 2000) found significantly higher rates of psychosocial disorders including depression and anxiety in individuals with untreated hearing loss -- those who were not wearing hearing aids.
A separate study at Johns Hopkins found that cognitive diminishment was 41 percent greater in seniors with hearing loss. The study identified a link between the degree of hearing loss and the risk of developing dementia. Individuals with mild hearing loss were twice as likely to develop dementia, those with moderate hearing loss were three times as likely, and those with severe hearing loss were five times as likely to develop dementia when compared to individuals with normal hearing.
Researchers and hearing care professionals have long understood the link between cognition and hearing acuity. When you are listening to someone speak your brain is processing the sound so that you can understand it. A listener with untreated hearing loss is trying to understand degraded speech signals therefore their brain has to work harder to process those sounds. While your brain is busy working to understand incoming speech signals other tasks like memory and comprehension can suffer.
Fortunately, hearing loss is treatable with the use of hearing aids. According to the Better Hearing Institute, 95 percent of Americans with hearing loss can be treated with hearing aids and individuals who treat their hearing loss early have shown significant benefit. Hearing aids help process incoming sound making it easier for your brain to understand them. Other benefits of hearing aids include reduced mental fatigue, decreased feelings of social isolation and depression, improved ability to do several things at once, improved memory, attention and focus, as well as improved communication skills.
Hearing care professionals often work in tandem with other medical professionals. If you or someone you love is experiencing cognitive or emotional problems schedule a physical exam with your doctor as well as a hearing evaluation with your audiologist. Hearing aids can lessen mental fatigue and feelings of isolation.
Why are there so many older people with hearing impairment who do not use hearing aids? More than two-thirds of the older, non-user respondents said "my hearing is not bad enough" or "I can get along without one." Hearing loss causes a reduction in the amount of sound that reaches the central auditory portions of the brain, and even in cases of mild hearing loss, will result in deprivation to the system. The body's natural response is a compensation mechanism that ultimately results in neuro-plasticity changes, where the vision and touch centers begin to take over the unused (deprived) auditory centers. These compensatory changes increase the overall load on the brains of aging adults. An appropriately fit hearing aid can provide more auditory input to the hearing centers as they are designed.
Hearing aid users reported significant improvements in many areas of their lives, ranging from their relationships at home and sense of independence to their social life. In virtually every dimension measured, the families of hearing aid users also noted the improvements but were even more likely than the users to report improvements.
Studies have linked untreated hearing loss effects to:
- irritability, negativism and anger
- fatigue, tension, stress and depression
- avoidance or withdrawal from social situations
- social rejection and loneliness
- reduced alertness and increased risk to personal safety
- impaired memory and ability to learn new tasks
- reduced job performance and earning power
- diminished psychological and overall health