Individuality – It’s easy to think that hearing loss is hearing loss, and that’s all there is to it. But it’s not that simple. Every single person is different, their hearing abilities are different, and their hearing needs are different. In fact, one person can have different hearing loss in each ear – meaning that your two ears can have different hearing needs! Learning about your hearing loss is a very important step before determining how to treat your hearing loss. So let’s learn about how we describe and categorize hearing loss.
We begin with a comprehensive hearing test, which is called an Audiogram. The audiogram is the way we plot your hearing thresholds on a graph. Threshold is just a fancy word meaning “the softest sound you can hear.” We measure your hearing in decibels (dB) – the decibel is the unit of measure for the volume of sound. So, as we use inches to measure a distance, we use decibels to measure the volume of a sound. The lower the decibel, the softer the sound is.
Now, hearing and understanding are two separate characteristics of our hearing system. Understanding will be covered another time.
Hearing – There are three different aspects of an audiogram that help us describe and categorize hearing (this is not the understanding part; we will get to that after we understand hearing):
- Type of hearing loss
- Degree of hearing loss
- Configuration of hearing loss
Today I will focus on the Type of hearing loss. Check back for posts on Degree and Configuration.
Type of Hearing Loss – There are 3 basic types of hearing loss
- Conductive – sound is not easily sent through the outer ear canal to the eardrum and the tiny bones (ossicles) of the middle ear. This type of hearing loss can often be corrected medically or surgically. Some possible causes of conductive hearing loss are:
- Fluid in the middle ear from colds or allergies
- Ear infection (otitis media)
- Poor eustachian tube function (likely feel like you need to “pop” your ears)
- Hole in the eardrum (perforation)
- Too much earwax (cerumen)
- Swimmer’s ear (otitis externa)
- Foreign body in the ear canal
- Malformation of the outer ear, ear canal, or middle ear
- Sensorineural – when there is damage to the inner ear (cochlea) or to the nerve pathways from the inner ear to the brain. Most of the time, this cannot be medically or surgically corrected. This is the most common type of permanent hearing loss. This reduces the ability to hear faint sounds. Even when speech is loud enough to hear, it may still be unclear or sound muffled. Some possible causes are:
- Drugs that are toxic to hearing (ototoxic drugs)
- Hearing loss that runs in the family (genetic or hereditary)
- Head trauma
- Malformation of the inner ear
- Exposure to loud noise (noise protection for another day!)
- Mixed – This is a combination of conductive and sensorineural hearing loss. There may be damage in the outer or middle ear (conductive) AND in the inner ear (cochlea) or auditory nerve.
I hope you found this helpful in beginning to learn about hearing loss. My next post will be on Degree of Hearing Loss – Check back to learn more!
“Honesty is the first chapter in the book of wisdom.”
– Thomas Jefferson