The Original Instrument: How the Ear Functions
BY CONOR KILKELLY
Ah, the humble ear, hidden away under unkempt hair, or the latest headsets, forced to listen to all manner of cringy teenage music in our formative years, left ringing after all-nighters at questionable nightclubs – safe to say, we often take our ears for granted.
But we want to help you get acquainted with the workings of the ear, in an effort to truly appreciate, understand and hopefully protect one of the most hardworking and most needlessly neglected of our sensory organs.
When Three Become One
The ear consists of three main sections, which work together to allow you to hear the world around you: The Outer Ear, The Middle Ear and The Inner Ear.
The Outer Ear
This handsome devil, known as the Pinna, is the one we’re most familiar with in our everyday lives. We pierce it, scratch it and some can even move it, however the Ear Canal is where the real magic lies (and, occasionally, wax, which is mostly there to repel insects which don't like bitter tastes ). This auditory canal channels sound down to the middle ear.
The Middle Ear
Sound waves travel down the ear canal and vibrate the Eardrum, which looks somewhat like the inside of a speaker and links directly to the Malleus, Incus and Stapes. These three components have another use, other than sounding perfect for a 90’s indie band name, as these tiny bones - in fact, the tiniest in our entire body, known as Ossicles have a knock on effect, almost like vibrating dominos which lead the sound waves to the inner ear, where sound is processed to be cognitively understood.
The Inner Ear
The inner ear is also referred to as The Cochlea, the Latin word for snail due to its uncanny resemblance to the insects’ shell. This fluid filled chamber converts the vibrations received from the Ossicles into electrical impulses that the brain receives through the Auditory Nerve and understands as sound. Yes, we hear through electricity, so, effectively we are the original- and digital, music players, even before vinyl players – take that hipsters!
The Organ of Corti: How Pitch is Heard
Perhaps the most fascinating and complex part of the ear is named the Organ of Corti, as, like an organ, it plays different pitches of sounds for the brain. It runs in circles along the cochlear snail and gradually changes in shape and stiffness so that it's tuned to different frequencies down its length. This entire construction is the sole reason we can distinguish high pitches from low sounds.
The Organ of Corti has an abundance of sensory cells called “hair cells” attached to nerve fibres. Depending on where such a cell sits along the Organ of Corti, it is sensitive to high or middle or low tones, covering the entire sound spectrum – and, as you would imagine, they are impossible to operate upon, being so tiny, delicate and deep within the ear, and for this reason, once damaged are essentially damaged for good.
Thankfully we have 16-20,000 hair cells on each side so don’t panic too much. However, old age, loud noises and even specific illnesses, such as Ménière’s Disease, can damage them.
Conclusion: Love your ears
In conclusion, your ear is nothing short of a wonder. It is the original instrument, vibrating and interpreting the sounds all around you for your brains listening pleasure (or to evade threats, and even to help you balance). The least you can do is remove your bucket hat for it on occasion.
Want to learn about how your own ears work? Download the award-winning Mimi Hearing Test for free, today!