Exploring the Ear
The ear is a small and fascinating precision instrument. It receives sounds and transmits the information to your brain. But how does it really work?
Here is a short voyage into the ear.
Sound waves carrying noise and speech are collected by the outer portion of the ear. These sound waves travel down the ear canal to the eardrum.
The sound waves cause the eardrum to vibrate. This in turn sets three ossicular bones — the anvil, the hammer, and the stirrup — in the middle ear into motion. The middle ear acts as a transformer, passing on the vibrations of sounds to the inner portion of the ear, known as the cochlea.
The vibration in the inner-ear fluid causes the hair cells that line the cochlea to move. The hair cells change this movement into electrical impulses.
These electrical impulses are sent up to the brain, via the auditory nerve, where they are interpreted as sound.
When damage occurs to the cochlea, the electrical impulses are not allowed to reach the nerve fibers that are responsible for carrying sound information to the brain.
Definition of Hearing Loss
A general description for deafness is the inability to hear and understand speech. Approximately one-fourth of the population represents this description. Here are two definitions of hearing losses:
A conductive hearing loss is damage that occurs to the outer or middle ear.
Nerve deafness, or sensorineural hearing loss, is damage that has occurred to the tiny hair cells within the cochlea. These damaged hair cells prevent the electrical impulses from reaching the auditory nerve fibers. Therefore, these fibers do not have information to send up to the brain.
The term “hard of hearing” is preferred over “hearing impaired” by the Deaf community and the hard of hearing when referring to individuals who have a hearing loss.
