To express that hearing loss is widespread is a bit of an understatement. In the US, 48 million individuals describe some degree of hearing loss. That means, 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 that, how do you prevent becoming one of those five?
To help you understand how to sustain healthier hearing all through your life, we’ll take a look at the causes and types of hearing loss in this week’s blog post.
How Normal Hearing Works
Hearing loss is the disturbance of normal hearing, so the best place to start off is with a familiarity of how normal hearing is intended to work.
You can think of normal hearing as comprised of three principal processes:
- The physical and mechanical transmission of sound waves. Sound waves are created in the environment and move through the air, like ripples in a pond, ultimately making their way to the external ear, through the ear canal, and finally hitting the eardrum. The vibrations from the eardrum are subsequently transmitted to the middle ear bones, which then stimulate 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 stimulated, translates the vibrations into electrical impulses that are delivered 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, oscillations, electricity, and chemical reactions. It’s a fully physical process that leads to the emergence of perception.
The Three Ways Normal Hearing Can Be Interrupted
There are three main types of hearing loss, each disrupting some feature of the normal hearing process:
- Conductive hearing loss
- Sensorineural hearing loss
- Mixed hearing loss (a mixture 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 due to anything that blocks conduction.
Examples include malformations of the outer ear, foreign objects inside the ear canal, fluid from ear infections, perforated eardrums, impacted earwax, and benign tumors, among other causes.
Treatment of conductive hearing loss includes removing the obstruction, dealing with 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 example from impacted earwax, you could start hearing better instantly after a professional cleaning. With the exclusion of the more serious varieties of conductive hearing loss, this form can be the easiest to treat and can restore normal hearing completely.
Sensorineural Hearing Loss
Sensorineural hearing loss disrupts the electrical conduction of sound from the inner ear to the brain. This is the result of injury to either the nerve cells within the cochlea or to the auditory nerve itself.
With sensorineural hearing loss, the brain receives compromised electrical signals, limiting the volume and clarity of sound.
The primary causes of sensorineural hearing loss are:
- Genetic syndromes or fetal infections
- Typical aging (presbycusis)
- Infections and traumatic injuries
- Meniere’s disease
- Cancerous growths of the inner ear
- Side effects of medication
- Sudden exposure to exceedingly loud sounds
- Long-term exposure to loud sounds
Sensorineural hearing loss is frequently connected with direct exposure to loud sounds, and so can be prevented by circumventing those sounds or by protecting your hearing with earplugs.
This form of hearing loss is a little more challenging to treat. There are no existing 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 responsibilities of the nerve cells, producing the perception of louder, sharper sound.
The third type of hearing loss, mixed hearing loss, is simply some combination of conductive and sensorineural hearing loss, and is treated accordingly.
If you have any trouble hearing, or if you have any ear discomfort or dizziness, it’s a good idea to talk to your physician or hearing professional as soon as possible. In virtually every case of hearing loss, you’ll attain the greatest results the earlier you treat the underlying problem.