How the Ear Functions

Introduction:

The ear has three main parts: the outer ear, middle ear, and inner ear. The outer ear (the part you can see) opens into the ear canal. The eardrum separates the ear canal from the middle ear. The middle ear contains three small bones which help amplify and transfer sound to the inner ear. These three bones are called the malleus, the incus, and the stapes. The inner ear contains the cochlea which changes sound into neurological signals and the auditory nerve, which takes sound to the brain.

Any source of sound sends vibrations or sound waves into the air. These funnel through the ear opening, down the external ear canal, and strike your eardrum, causing it to vibrate. The vibrations are passed to the three small bones of the middle ear, which transmit them to the cochlea. The cochlea contains tubes filled with fluid. Inside one of the tubes, tiny hair cells pick up the vibrations and convert them into nerve impulses. These impulses are delivered to the brain via the hearing nerve. The brain interprets the impulses as sound.

The model above displays how the ear functions as well. The water container is filled up with no air bubbles being allowed. The top side of the center line conatins nerve cells that capture the vibrations, and the bottom side conatins basilar membranes that assist the nerve cells in translating the vibrations into signals. The crank is attached to the three internal ear bones, the malleus, the incus, and the stapes. The crank turns which causes vibrations, which also causes the water to vibrate and display the bones catching the signals and transfering them to the brain. The brain then captures the neurological signals through the brain cells and there the signals turn into sound.