Hearing loss: A silent epidemic
Everyone experiences hearing loss from time to time: ear wax, ear infections, and the ear-popping sensation that bothers air passengers during takeoff are common causes of temporary hearing loss. And a mild degree of permanent hearing impairment is an inevitable part of the aging process. But for over 29 million Americans, the problem is more serious. Major hearing loss becomes more common with increasing age, particularly after age 65, and men are 5.5 times more likely than women to have hearing loss that makes communication difficult. Fortunately, modern medical care can help.
How you hear
The ear is divided into three parts (see figure). The outer part consists of the external ear and the ear canal. The middle ear consists of the eardrum, or tympanic membrane, and three small bones, or ossicles (the malleus, incus, and stapes). The inner ear, or labyrinth, is the most complex. It includes the cochlea, the three semicircular canals, which are responsible for balance, and one end of the auditory nerve, which connects to the brain.
The external ear collects sound waves, and the ear canal funnels them to the eardrum. As sound waves strike the eardrum, they cause it to vibrate. The vibrations are relayed along the chain of tiny bones in the middle ear until they reach the third bone, which connects to the cochlea.