Ears are made up of a visible outer ear and a complex inner ear which does the heavy lifting of hearing. Your ears are responsible for transforming sound waves into electrical impulses read by the brain as sound, but ears are also responsible for your sense of balance and direction.
The ears are made up of many different parts that all work together to transfer sounds from the outside to your brain, and also to keep you balanced. In this article, we will be looking at the three main parts of the ear as well as other necessary parts!
3 Main Parts of the Ear
1. The Outer Ear
Outer ears can be all different shapes, formed by cartilage and skin. Outer ears are also known as “auricles” or “pinnas.” The outer ear is the visible part of the ear that we see and also the part of the ear that we think of when we start to talk about “ears.”
The outer ear is the part that is responsible for capturing sound waves and sending them further into the ear. This is why it has a funnel or megaphone shape. The outer ear is also a protective design, preventing larger objects from entering the ear canal and eardrum.
2. Middle Ear
The middle ear is the space inside the eardrum, where three of the smallest bones in the body are found (the middle ear ossicles).
The malleus (hammer), incus (anvil), and stapes (stirrup) react to sound. The ossicles function together like a piston to stimulate hair cells in the cochlea.
The ear is created to capture and funnel sound, which makes it a high-intensity pressure chamber. To mitigate this pressure, the body developed a eustachian tube which links the middle ear with the back of the nose to equalize pressure. The stable pressure helps properly transfer sound waves. The eustachian tube is filled with the same type of mucous that the nose and throat are.
3. Inner Ear (Cochlea and Labyrinthine)
The inner ear is a two-part compartment between the middle ear and the skull, containing the mechanisms for hearing and balance.
The cochlea allows you to hear. This part of the ear is two snail-shaped chambers filled with fluid which are vibrated by sound. The small hairs in the cochlea vibrate, sending electrical impulses to the brain which are read as sound.
The other portion of the inner ear is the labyrinthine, semicircular canals which are filled with fluid and calcium crystals. The Labyrinthine tell your brain what direction your head is moving and facing relative to gravity. While your hearing apparatus only sends impulses when stimulated, the labyrinthine is always “on,” constantly sending information to the brain about how your head is moving and which direction you’re facing.
The labyrinthine is made up of vestibules and semicircular canals, both of which contain receptors for balance.
Other Parts of the Ear
4. Ear Canal
The ear canal stretches from the cartilage of the outer ear to the eardrum inside the ear. The skin is sensitive to pressure, protecting the canal from unwanted objects and sounds that might damage the eardrum. Your ear canal will warn you that sounds are too loud before you damage your eardrums or inner ear.
The makeup of the ear canal is two-thirds bone and one-third cartilage. The ear canal is stronger and sturdier than the outer ear as added protection for the fragile inner ear.
This important part of the ear is responsible for funneling sound from the outer ear into the eardrum.
5. Eardrum (Tympanic Membrane)
The eardrum is a dime-sized transparent gray membrane which is at the end of the ear canal, and is attached to the middle ear.
When sound hits the eardrum from the ear canal, the eardrum vibrates and in turn vibrates the adjacent ossicles in the middle ear.
6. Eighth Cranial Nerve
The eighth cranial nerve, or auditory nerve, carries information about balance and hearing from your inner ear (labyrinthine and cochlea) to your brain in the form of electrical impulses. The cochlea transforms sound waves (vibrations) into electrical impulses, and the eighth cranial nerve acts as a highway for those impulses, shuttling them from ear to brain.
The ear is instrumental in helping you hear and find your balance. Balance is derived from the labyrinthine in the inner ear, which uses fluid and gravity to tell your brain where your head’s at. Sound travels through the outer ear, ear canal and inner ear to the eardrum where it causes vibrations in the cochlea which are transformed into electrical impulses.
I hope that this article on parts of the ear was helpful! If you are interested, visit the health facts page!