The external ear is the part of the auditory system that collects sound waves and directs them to the tympanic membrane (eardrum). It is comprised of the pinna (also known as the auricle) and the external auditory meatus (ear canal).
What is the Function of the External Ear?
The external ear has two main functions:
- To collect sound waves and direct them to the tympanic membrane. The pinna’s shape helps to collect sound waves from all directions and direct them into the ear canal. The ear canal then amplifies the sound waves slightly before they reach the tympanic membrane.
- To protect the tympanic membrane. The pinna helps to protect the tympanic membrane from injury by blocking out large objects and harmful particles. The ear canal also produces cerumen (earwax), which helps to protect the tympanic membrane from infection.
What is the Function of the External Ear and Internal Ear?
The external ear and the internal ear work together to transmit sound waves to the brain. The external ear collects sound waves and directs them to the tympanic membrane. The tympanic membrane then vibrates in response to the sound waves. These vibrations are then transmitted to the ossicles (three small bones in the middle ear). The ossicles amplify the vibrations and transmit them to the inner ear. The inner ear contains the cochlea, which is a spiral-shaped structure that converts the vibrations into electrical signals. These electrical signals are then sent to the brain, where they are interpreted as sound.
What is the Structure of the External Ear?
The external ear is made up of the following structures:
- Pinna: The pinna is the visible part of the ear. It is made up of cartilage and skin.
- External auditory meatus: The external auditory meatus is the canal that leads from the pinna to the tympanic membrane. It is lined with skin and contains ceruminous glands, which produce earwax.
- Tympanic membrane: The tympanic membrane is a thin, delicate membrane that separates the external ear from the middle ear. It vibrates in response to sound waves.
Where is the external ear found?
The external ear is located on the side of the head, just above the earlobe.
Common Conditions of the External Ear
Some common conditions of the external ear include:
- Otitis externa: Otitis externa is an inflammation of the external auditory canal. It is often caused by bacteria or fungi.
- Cerumen impaction: Cerumen impaction is a buildup of earwax in the external auditory canal. It can cause hearing loss and pain.
- Aural atresia: Aural atresia is a congenital absence or underdevelopment of the external auditory canal.
- Microtia: Microtia is a congenital deformity where the pinna is underdeveloped or incompletely formed.
The external ear is an important part of the auditory system. It collects sound waves and directs them to the tympanic membrane. The external ear also helps to protect the tympanic membrane from injury. Common conditions of the external ear include otitis externa, cerumen impaction, aural atresia, and microtia.