It is deaf awareness week, so it’s the perfect time to discuss everything ear related!
Firstly, it might be best to understand how our ears actually work. Brace yourself for a very epic journey into your ears...
They are designed to gather sound waves via the outer ear. This is the visible part of the ear that we see on each side of our head, and is called the pinna. The sound then travels down the ear canal, the part that sometimes can have a buildup of earwax (the earwax keeps the canal and inside ear moist and clean). At the end of the ear canal is the eardrum, which vibrates when the sound waves touch it. Behind this drum are three incredibly tiny bones (the smallest in your body!), which move about as the eardrum vibrates. In the inner ear after these bones is an organ called the cochlea that has fluid inside of it - the movement of the little bones causes that fluid to ripple and the wave formed brushes across some sensory hair cells. These hairs ride the wave up and down, opening up some pores at their tips. Chemicals rush through the open pores into the cells, generating an electrical signal that’s sent to the brain for processing. Very complicated indeed!
So, what is deafness?
There are four different types of hearing loss altogether.
- Conductive Hearing Loss - something is blocking the sound from crossing through the out outer or middle of the ear. Often it can be treated with surgery or medicine to remove the blockage.
- Sensorineural Hearing Loss - there is a problem with how the hearing nerves are working or the inner ear.
- Mixed Hearing Loss - a mix of the two detailed above
- Auditory Neuropathy Spectrum Disorder - the sound enters the ear as it sound do, but the brain cannot make sense of what it’s being told as there may be damage to the inner ear or hearing nerve.
You can also have varying degrees of each form of hearing loss too. Ranging between mild (can hear speech but quieter sounds are inaudible), moderate (may hear almost no speech if someone is speaking at a normal decibel), severe (no speech can be heard and some loud sounds) and profound (only very loud sounds).
There are many different ways deafness can affect the person, they may only be deaf in one ear (unilateral) or both ears (bilateral). They might have the same amount of loss in both ears (symmetrical) or it might differ between each (asymmetrical). Their loss of hearing may fluctuate and get better or worse over time, or it may have stabilised so that it is the same continuously. They could have been born with their hearing loss (congenital) or it may have developed in a number of ways during their life (delayed onset/acquired). If they were born with it, they would also be classed as pre-lingual, as the hearing loss occurred before that person learnt to talk. If it was after they learnt to talk,the term would be post-lingual. And the final difference would be whether the hearing loss was sudden or whether it progressively worsened over time.