What structures in the ear make hearing possible?
The ear is composed of three sections; the external, middle, and innner sections. The outer visible section is made up of hard cartilage and covered by skin, this is know as the pinna and where sound is collected. From the pinna sound travels to the external auditory canal and this sound makes the tympanic membrane (eardrum) vibrate. The middle ear is made up the anvil, stirrup, and hammer. Then the vibrations are sent to the inner ear, the cochlea then those vibrations change to nerve impulses. A more in depth discussion of how soundwaves travels in the ear is found in the waves tab.
What conditions affect hearing?
Several conditions can affect person's hearing such as otitis media, tinnitus, ruptured eardrum, cerumen, and acoustic neuroma.
- Otitis media is inflammation of the middle ear caused by infection.
- Tinnitus in simple terms means ringing of the ears caused by aging or from long term exposure to loud noises.
- Ruptured eardrum is caused by loud noises, a foreign oject, or a change in air atmosphere.
- Cerumen is the same thing as saying ear wax and a build up of cerumen in the ear canal causes the vibrations in the eardrum to decrease.
- Acoustic neuroma is a noncancerous tumor that is located on the nerve that carries he nerve impulses traveling from the ear to the brain.
How is hearing loss diagnosed?
Hearing loss is diagnosed with the use of several medical exams. An ear exam will check to see the ear canal with the use of an otoscope. An auditory exam looks to see if a person can hear a different sounds with different volume and frequencies. Magnetic resonance imaging creates images with high resolutions of the ear and its structures with the use of radio waves in a magnetic field.