Understanding the 3 Main Types of Hearing Loss
The first step to fixing a problem is understanding the problem. We help people overcome hearing difficulties every day at The Hill Hear Better Clinic, but we know that hearing loss can be a difficult problem to understand. This May, we’re recognizing Better Hearing and Speech Month by helping you take that first step and understand the three main types of hearing loss.
Sensorineural hearing loss
Your ear is made up of three parts: outer, middle, and inner. Sensorineural hearing loss has to do with what happens in the inner ear, inside of which are lots of tiny parts that capture sound. Your inner ear houses thousands of hair cells which react to sound by vibrating. The vestibulocochlear or auditory nerve captures this vibration in the form of electrical potential and transmits it to the brain, which perceives it as sound.
Sensorineural hearing loss occurs when these hair cells or the auditory nerve are damaged. Hair cells can naturally degrade over time, which is why our hearing tends to get worse as we get older. This process is called presbycusis.
However, hair cells are extremely sensitive and are prone to damage from loud noise, extended exposure to noise, and external trauma or injuries. They can also be affected by certain medications and illnesses, like cancer treatments, obesity, or even cardiovascular disease. The nerve cells transmitting the signal to the brain can also be affected by neurological disorders, noise, or even acoustic neuromas (benign brain tumors that affect the auditory nerve).
How do you know if you have it?
Sensorineural hearing loss doesn’t just make the world quieter – it can actually affect your hearing in some surprising ways. You may experience tinnitus, a ringing or buzzing sound in your ears. Things may seem either too quiet or too loud, and you may have issues discerning high-pitched sounds or certain speech sounds. Other people may seem to mumble or have slurred speech when you talk to them. You might also have difficulty listening in a noisy environment. You may even feel dizzy!
This is due to high-frequency hearing loss. The tiny hair cells in your inner ear cannot heal themselves or be repaired surgically – once they’re gone, they’re gone. And when they are, your brain isn’t getting auditory signals that it can put together as intelligible sound.
While hair cells can’t be fixed, don’t lose hope for your hearing! Sensorineural hearing loss can be overcome relatively easily with the use of hearing aids or cochlear implants, depending on the cause and severity of the hearing loss.
Conductive hearing loss
Your outer ear is the part of your ear that you can see, including the ear canal all the way up to the eardrum. The middle ear, like the inner ear, contains tiny parts that work together to help you hear. These include the smallest bones in your body: the malleus, incus, and stapes (better known as the hammer, anvil, and stirrup). It also opens to the Eustrachian tube, the passage that connects your ear to your throat and nasal cavity.
The job of the middle and outer ear is to conduct sound into the inner ear. When either of them are damaged or blocked, you may experience conductive hearing loss. It has a wide variety of causes, but we can break them down by what part of the ear they affect.
Conductive hearing loss in the outer ear can be caused by foreign bodies or liquids in the ear, like in the case of swimmer’s ear (medically known as otitis externa). It can also be caused by wax impaction, which is why you should have your ears safely cleaned by a professional. But it can also have a more complex cause, such the ear canal narrowing (stenosis) or the growth of bony protrusions (exostoses).
In the middle ear, conductive hearing loss can be caused by an eardrum breach. Ear infections, intense air pressure changes, and injuries can all rupture your eardrum. Even if it doesn’t cause a breach, an ear infection can still lead to a fluid buildup and loss of hearing. You may also experience conductive hearing loss if your Eustrachian tube becomes blocked or if the small bones in your middle ear are damaged or affected by medical conditions.
How do you know if you have it?
Unlike the sensorineural variety, conductive hearing loss can come with more discomfort and may affect one ear and not the other. Because the workings of your inner ear are intact, you likely won’t struggle as much with clarity as with a low volume. If you’re experiencing pressure or pain in one or both of your ears or a difference in hearing between your ears, you may be suffering from this type of hearing loss.
Conductive hearing loss can be treatable in some cases. Wax impaction, foreign objects, or growths can be removed, while ear infections can be treated with antibiotics. Other causes cannot be completely fixed; stenosis and exostoses, for example, will likely cause permanent hearing loss. In these cases, hearing aids and other solutions can help correct the problem.
Mixed hearing loss
The third type of hearing loss is a combination of the other two and can have different results. Injuries can affect multiple parts of the ear and result in mixed hearing loss. Compounding conductive hearing issues can also lead to inner ear damage and mixed hearing loss.
This kind of hearing loss can also be temporary. If someone has permanent sensorineural hearing loss and also suffers from an ear infection that causes conductive hearing loss, their hearing loss is considered mixed. When the infection is treated and their hearing goes back to a normal level, their hearing loss will again be considered sensorineural.
The kind of treatment needed for mixed hearing loss depends on the causes. Many permanent mixed conditions can be treated with hearing aids.
How is hearing loss measured?
Audiologists reference the amount of hearing loss you experience through four levels of severity: Mild, Moderate, Severe, and Profound. At the Mild level, you might only have trouble with softer speech sounds, but at the Profound level you might not be able to hear any speech sounds at all.
Your level of hearing loss isn’t static throughout your life. As you age, you may progress from one level to the next. If you undergo treatment for a hearing loss condition, you could go from a higher level to a lower one as your hearing improves.
Take the next step
If any of these types of hearing loss remind you of yourself or a loved one, an audiologist can help. At The Hill Hear Better Clinic, we can help you make an informed decision about your treatment options. Now that you’ve taken the first step toward better hearing, let’s take the next one together!