To say that hearing loss is widespread is a bit of an understatement. In the United States, 48 million people describe some level 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 avoid becoming one of those five?
To help you understand how to sustain healthier hearing throughout your life, we’ll take a closer look at the causes and types of hearing loss in this week’s posting.
How Normal Hearing Works
Hearing loss is the interruption of normal hearing, so the best place to begin is with an understanding of how normal hearing is intended to work.
You can think of normal hearing as consisting of three main processes:
- The physical and mechanical transmission of sound waves. Sound waves are created in the environment and propel through the air, like ripples in a lake, ultimately making their way to the external ear, through the ear canal, and ultimately striking the eardrum. The vibrations from the eardrum are subsequently transmitted to the middle ear bones, which then trigger the tiny nerve cells of the cochlea, the snail-shaped organ of the inner ear.
- The electrical transmission from the inner ear to the brain. The cochlea, once stimulated, converts the vibrations into electrical signals that are transmitted via the auditory nerve to the brain.
- The perception of sound in the brain. The brain perceives the electrochemical signal as sound.
What’s fascinating is that what we perceive as sound is nothing more than sound waves, vibrations, electricity, and chemical reactions. It’s a completely physical process that leads to the emergence of perception.
The Three Ways Normal Hearing Can Go Wrong
There are three principal types of hearing loss, each disrupting some component of the normal hearing process:
- Conductive hearing loss
- Sensorineural hearing loss
- Mixed hearing loss (a mix of conductive and sensorineural)
Let’s take a closer look at the first two, including the causes and treatment of each.
Conductive Hearing Loss
Conductive hearing loss impedes the physical and mechanical conduction of sound waves to the inner ear and cochlea. This is caused by anything that hinders conduction.
Examples include malformations of the outer ear, foreign objects within the ear canal, fluid from ear infections, pierced eardrums, impacted earwax, and benign tumors, among other causes.
Treatment of conductive hearing loss includes extracting the obstruction, treating the infection, or surgical correction of the malformation of the outer ear, the eardrum, or the middle ear bones.
If you suffer from conductive hearing loss, for instance from impacted earwax, you could possibly start hearing better immediately following a professional cleaning. With the exclusion of the more serious kinds of conductive hearing loss, this form can be the simplest to treat and can bring back normal hearing entirely.
Sensorineural Hearing Loss
Sensorineural hearing loss inhibits the electrical conduction of sound from the cochlea to the brain. This results from damage to either the nerve cells within the cochlea or to the auditory nerve itself.
With sensorineural hearing loss, the brain is provided with compromised electrical signals, decreasing the volume and clarity of sound.
The chief causes of sensorineural hearing loss are:
- Genetic syndromes or fetal infections
- Normal aging (presbycusis)
- Infections and traumatic injuries
- Meniere’s disease
- Cancerous growths of the inner ear
- Side effects of medication
- Sudden exposure to very loud sounds
- Long-term subjection to loud sounds
Sensorineural hearing loss is most commonly associated with direct exposure to loud sounds, and so can be prevented by staying clear of those sounds or by defending your hearing with earplugs.
This form of hearing loss is a bit more difficult to treat. There are no present surgical or medical procedures to repair the nerve cells of the inner ear. However, hearing aids and cochlear implants are very effective at taking over the amplification assignments of the nerve cells, leading to the perception of louder, clearer sound.
The third type of hearing loss, mixed hearing loss, is basically some mixture of conductive and sensorineural hearing loss, and is treated accordingly.
If you have any difficulties hearing, or if you have any ear discomfort or dizziness, it’s a good idea to talk with your physician or hearing professional right away. In virtually every instance of hearing loss, you’ll attain the greatest results the sooner you deal with the underlying issue.