Facts About Ears

Human ears consist of three parts: the outer ear, middle ear and inner ear. Sound is relayed through this delicate system through a series of vibrations from component to component. Deafness occurs if one of these components is damaged or missing.

Movement

The human ear is fixed on either side of the human head, the top equal with the brow and the bottom equal with the mouth. Humans do not have the muscles to turn their ears in any direction, although some can wiggle them up and down.

Cochlea and Semi-Circular Canals

The inner ear connects to the auditory nerve via a bone called the cochlea, shaped like a shell. It receives vibrations from a bone called the stirrup, connected to the cochlea via a liquid-filled sack called the semi-circular canals. The semi-circular canals help maintain our sense of balance.

Stirrup

The stirrup, or stapes, is part of the middle ear, which receives vibrations from a bone called the anvil. It is a U-shaped bone connecting the anvil to the semi-circular canals.

Hammer and Anvil

The hammer, or malleus, receives vibrations from the eardrum and sends the vibrations to a bone called the anvil, or incus. Below the hammer and behind the eardrum is the Eustachian tube, which connects to the nose, equalizing the air pressure between the air outside and where the hammer and anvil are located, called the middle ear.

Outer Ear to Eardrum

The eardrum is a thin membrane, also called the tympanic membrane, that receives sound waves through the auditory canal causing it to vibrate. The outer ear, called the pinna or auricle, collects the sound and channels it through the auditory canal.

References

• Ear Anatomy
• Human Ear