“I often hear from my patients that they feel that people are mumbling or that voices don’t sound clear to them.”
This happens because of damage in the inner ear: the sound signal isn’t being processed correctly, so the brain doesn’t receive the information it needs to understand speech.
How Your Ear Works
Your ear has three major areas: the outer ear, middle ear and inner ear. Sound waves pass through the outer ear and cause vibrations at the eardrum. The eardrum and three small bones of the middle ear amplify the vibrations as they travel to the inner ear. There, the vibrations pass through fluid in a snail-shaped structure (the cochlea). Attached to nerve cells in the cochlea are thousands of tiny hairs that translate sound vibrations into electrical signals sent to your brain. Different sounds move these tiny hairs in different ways, so the nerve cells send different signals — that’s how you tell one sound from another.
Types of Hearing Loss
Conductive hearing loss
Conductive hearing loss is a decrease in sound caused by a problem in the outer or middle ear. It is often treatable with the right intervention, such as medicine or surgery. Causes include ear infections (which tend to cause fluid in the middle ear), wax in the ear canal, and a perforated eardrum.
Sensorineural hearing loss
Sensorineural hearing loss is a problem in the inner ear and/or the nerve pathways between the inner ear and the brain. Among the most common causes:
- Aging
- Infection
- Noise exposure — recreational, occupational or military
- Meningitis
- Certain genetic disorders
- Ménière’s disease
- Viruses
Sensorineural hearing loss cannot be cured medically, but hearing may be improved with hearing aids.
Mixed hearing loss
Mixed hearing loss is a conductive and a sensorineural hearing loss at the same time: the inner ear or nerve pathways are damaged and there is a blockage in the outer or middle ear. The conductive part can usually be corrected; the sensorineural part is permanent, and hearing aids can often help.
Next Steps
The only way to know what kind of hearing loss you have is a hearing assessment. Keep learning with how to read your audiogram, our audiology FAQ and Hearing Aids 101.