The Ear and Hearing

The ability to hear is something we may take for granted. But our ability to listen to, enjoy and comprehend the sounds around us is nothing to take lightly. Hearing actually depends on a complex series of events. Basically, sound waves in the air translate into electrical impulses, which are carried to the brain along the auditory nerve. (Read about "The Brain" "Nervous System")

Here's what happens, according to the National Institute on Deafness and Other Communication Disorders (NIDCD):

First, sound enters the ear, which consists of three major parts: the outer ear, middle ear and inner ear. Sound waves enter the outer ear and travel through the ear canal to the eardrum. The eardrum vibrates from the incoming sound waves and transmits these vibrations through three tiny bones called the ossicles (the malleus, incus and stapes) in the middle ear. These tiny bones amplify the sound and send it to the inner ear and into the fluid-filled hearing organ called the cochlea. Here, the vibrations create ripples in the fluid that bend projections from tiny hair cells in the cochlea, causing electrical impulses that the auditory nerve or eighth cranial nerve, sends to the brain. The brain then translates these impulses into what we experience as sound.

Because of the complexity of both our ears and the process that leads to hearing and comprehension, many things can go wrong. The following links will take you to some of the more common problems that affect our sense of hearing.