To say that hearing loss is common is somewhat of an understatement. In the United States, 48 million people report some extent of hearing loss. As a result,, on average, for every five people you encounter, one will have hearing loss. And at the age of 65, it’s one out of three.
With odds like this, how can you escape becoming one of those five?
To help you understand how to maintain healthier hearing throughout your life, we’ll take a look at the causes and types of hearing loss in this week’s posting.
How Healthy Hearing Works
Hearing loss is the interruption of normal hearing, so the best place to start is with an understanding of how normal hearing is intended to work.
You can picture normal hearing as composed of three main processes:
- The physical and mechanical conduction of sound waves. Sound waves are produced in the environment and move through the air, like ripples in a pond, eventually making their way to the external ear, through the ear canal, and finally hitting the eardrum. The vibrations from the eardrum are then transferred to the middle ear bones, which then arouse the tiny nerve cells of the cochlea, the snail-shaped organ of the inner ear.
- The electrical conduction from the inner ear to the brain. The cochlea, once activated, converts the vibrations into electrical impulses that are sent via the auditory nerve to the brain.
- The perception of sound within the brain. The brain perceives the electrochemical signal as sound.
What’s interesting is that what we perceive as sound is nothing more than sound waves, oscillations, electric current, and chemical reactions. It’s a wholly physical process that leads to the emergence of perception.
The Three Ways Normal Hearing Can Go Wrong
There are three main types of hearing loss, each interfering with some factor of the normal hearing process:
- Conductive hearing loss
- Sensorineural hearing loss
- Mixed hearing loss (a combination of conductive and sensorineural)
Let’s take a look at the first two, including the causes and treatment of each.
Conductive Hearing Loss
Conductive hearing loss interferes with the physical and mechanical conduction of sound waves to the inner ear and cochlea. This is a consequence of anything that obstructs conduction.
Examples include malformations of the outer ear, foreign objects inside the ear canal, fluid from ear infections, pierced eardrums, impacted earwax, and benign tumors, among other causes.
Treatment of conductive hearing loss includes getting rid of the obstruction, treating the infection, or surgical correction of the malformation of the outer ear, the eardrum, or the middle ear bones.
If you have conductive hearing loss, for instance from impacted earwax, you could possibly start hearing better immediately after a professional cleaning. With the exception of the more severe kinds of conductive hearing loss, this type can be the easiest to treat and can restore normal hearing entirely.
Sensorineural Hearing Loss
Sensorineural hearing loss inhibits the electrical conduction of sound from the cochlea to the brain. This is due to the deterioration to either the nerve cells within the cochlea or to the auditory nerve itself.
With sensorineural hearing loss, the brain receives weak electrical signals, limiting the volume and quality of sound.
The chief causes of sensorineural hearing loss are:
- Genetic syndromes or fetal infections
- Regular aging (presbycusis)
- Infections and traumatic injuries
- Meniere’s disease
- Cancerous growths of the inner ear
- Side effects of medication
- Abrupt exposure to very loud sounds
- Long-term exposure to loud sounds
Sensorineural hearing loss is typically associated with direct exposure to loud sounds, and so can be prevented by staying away from those sounds or by protecting your hearing with earplugs.
This form of hearing loss is a bit more challenging to treat. There are no existing surgical or medical procedures to heal the nerve cells of the inner ear. However, hearing aids and cochlear implants are extremely effective at taking on the amplification duties of the nerve cells, bringing about the perception of louder, crisper sound.
The third type of hearing loss, mixed hearing loss, is essentially some mixture of conductive and sensorineural hearing loss, and is treated accordingly.
If you have any difficulty hearing, or if you have any ear discomfort or dizziness, it’s a good idea to pay a visit to your physician or hearing professional as soon as possible. In nearly every case of hearing loss, you’ll attain the best results the earlier you take care of the underlying issue.