Ears: How Do They Work?

No, ears are not just holes that go right through your head, they are actually quite complex organs. Lets start with the outer part and make our way in!

The most outer part that we usually pierce is called the Pinna, and as you can see, the part that is a little bit deeper is the Concha, and the actual hole where you usually stick your fingers in when you don't want to listen to someone is called the External Meatus.

The outer ear is responsible for figuring out which direction a sound is coming from. It also amplifies and attenuates (makes quieter) certain sounds.

There is a very thin membrane between the Outer and Middle ear. It's called the tympanic membrane also known as the eardrum. The main reason for this membrane is to transmit the sound waves from air to the middle ear bones.

The middle ear contains 3 bones and some muscles that connect the bones together. The English names for these bones are "hammer", "anvil" and "stirrup". The "hammer" is attached to the eardrum, so when the eardrum vibrates, the hammer also moves. Because all three bones are attached, all three bones move when the eardrum vibrates. It's a nifty little unit that works together. Praise those little workers for letting you hear!

The bones are arranged in order of biggest to smallest starting from the "hammer" and ending with the "stirrup". The change in size allows for more sound amplification in certain sounds. The main job of these bones is to transfer the sound energy from outer to inner ear. Think of it as a relay station or a translator of a sorts that also acts as an amplifier.

There is also another little feature in the middle ear called the eustachian tube. This tube connects the middle ear to the throat. This is an important feature because the eustachian tube balances the pressure between middle ear and the outside. Think about how your ears feel when you are on a plane. You probably feel a pressure on your ear drum. It can be uncomfortable and even painful. Chewing gum or swallowing usually helps that. The reason this works is because the eustachian tube opens during yawning and swallowing. So when you're swallowing, you're actually opening up the eustachian tube and equalizing the pressure between the outside and your middle ear.

The inner ear contains two main organs: the cochlea(sound) and the vestibular system (balance).

The cochlea is a spiral shaped organ (snail shell) that is responsible for transmitting sound energy from middle ear to neurons. The cochlea contains liquid and many very complex features! Some of the most important features are:

- Basilar Membrane
- Hair Cells
- Tectorial Membrane

There is a tiny membrane called the oval window between the middle and the inner ear. The "stirrup" footplate pushes against the oval window when a sound is being transmitted. The oval window is connected to the cochlea on the other side, and when the oval window is being pushed, liquid in the cochlea is being displaced, think water waves.

The basilar membrane runs along the full length of the cochlea. If you were to unroll the cochlea, you'll find the basilar membrane running from base to tip of the cochlea. This membrane is surrounded by liquid, and starts moving when the liquid is being displaced. Each part of the basilar membrane is responsible for a certain sound frequency.

The basilar membrane contains little hair cells on its surface. These haircells contain sensors that are attached to neurons.

The tectorial membrane is on top of the basilar membrane, and when the basilar membrane is displaced, the haircells touch the tectorial membrane causing a shearing movement.

When the haircells shear against the tectorial membrane, they send messages to neurons. These messages then travel to the brain. This is how we perceive hearing! It would probably be something like rubbing your hand on top of your hairbrush bristles. That movement sends messages to your brain saying, "Hey buddy, your cat is meowing for more food!"

The Vestibular System is responsible for our balance and spatial orientation. It pretty much helps us avoid bumping into a chair, and falling over when we do yoga. This system is closely related to our eyes, so vertigo and motion sickness are usually caused by a problem with this system (sometimes we call this problem "too many margaritas"). Since this page was really made about hearing, this is all I will say about the vestibular system.

What is the point of earwax, and what is it anyway? It's gooey and kinda nasty looking. Turns out, earwax is a mix of thicker secretion of sebaceous glands and apocrine sweat glands . So pretty much dead skin and sweat. Now don't go running for your Q-tips! Read on!

Wax, or what professionals call cerumen, is actually there for your benefit. It cleans and lubricates your ear and also acts as an anti-bacterial, anti-fungal, and anti-insecticide! This stuff is actually awesome! So put those Q-tips away!

In fact, using cotton swabs inside your ear canal is a terrible idea. Ear wax only forms in the first 3rd of your ear, so when you're cleaning your ears, you're actually pushing some of the earwax in a part of the ear where it does not belong! After a number of "cleanings", all that earwax that you unknowingly push inside the ear can form an nice little plug. This plug can cause some hearing loss, so if this does happen, go on to an audiologist or another trained professional who will clean that out for you. Earwax removal usually happens on its own! Jaw movement aids in pushing out the earwax safely and naturally.

Another more severe problem with using a cotton swab in your ear canal is accidents that can happen during its use. What if someone accidentally walks by and bumps your elbow as you're cleaning your ear? Goodbye, eardrum! There are a number of problems that can happen when you're sticking a stick with a bit of cotton inside your very sensitive, fragile ear!

You can say, "Well what if I have a ton of earwax that actually causes problems on its own?" There are other safer solutions for that problem. These treatments have the fancy name of cerumenolysis . Ask about them in your local pharmacy. They are readily available over the counter. Usually they are just certain oils that you put in your ear. Very safe and reliable.

Most people experience a strange sensation at some point in their lives. It is a strange ringing, buzzing, chirping, and some other strange regular sounds that seem to come from the inside of the ear. This is called Tinnitus.

There are two types of tinnitus: objective and subjective. Objective tinnitus may sometimes be heard by others, while subjective cannot be heard by others. The two different types usually also have different causes. Objective may be caused by muscle spasms, while subjective are usually more neural in nature.

If you have objective tinnitus, it is a good idea to see your doctor because it may be indicative of a much bigger problem.

Subjective tinnitus is a lot more common than objective, and can be experienced by anyone. A more severe persistent tinnitus may be due to certain medications, an early sign of hearing loss, and other dangerous pathologies. If it is persistent and problematic, don't hesitate to go to your doctor.

If it's a rare occurrence, then don't worry so much. We all get it sometimes!

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Take care of your ears! Stay informed! If you want to know more about ears, give me suggestions!

Most images taken from Wikipedia