- The external ear collects and concentrates sound energy.
- The ear canal carries sound to the eardrum, a membrane separating
the canal and the middle ear.
- The eardrum vibrates in response to changes in sound energy
setting into motion three tiny bones.
- The tiny bones of the middle ear vibrate against the fluid filled
cochlea, transmitting the sound energy into the fluid.
- Inside the cochlea, special nerve cells pick up the sound waves in
the fluid and generate nerve impulses.
- The auditory (hearing) nerve carries nerve impulses from the cochlea
to the brain, where they are received and heard as a sound.
Normal Hearing
Your ear has three parts, each with a different purpose. The outer
ear collects sound and funnels it to the middle ear. There the
sound is amplified (made stronger) and sent to the inner ear,
where it is converted into nerve impulses (signals) that go to the
brain. The brain compares the loudness of incoming signals from
each ear to determine the direction of the sound.