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There are two basic types of deafness: conduction deafness and nerve deafness. The former usually involves problems with structures in the outer or middle ear; the latter is a more serious condition resulting from damage to the inner ear or auditory nerve.
How many times have you been told not to put anything smaller than your elbow into your ear? My grandmother would always tell us that, and I found it pretty funny until I discovered that a ruptured eardrum can cause a loss of hearing called conduction deafness. Conduction deafness results from a structure in the outer or middle ear not functioning properly. This type of deafness can be congenital (from birth), or it may be caused by damage to the ear from an injury or infection. Temporary conduction deafness could result from a head cold or a buildup of wax. Fortunately, many people with conduction deafness can be helped with a hearing device that helps conduct sounds to the inner ear, where they can be transformed into nerve impulses and sent to the brain. A more severe problem occurs when the inner or auditory nerve is damaged or missing. Nerve deafness could result in the loss of ability to hear high-frequency sounds, or in the total loss of hearing. Often nothing can be done when nerve deafness occurs, since a hearing aid cannot make a nonexistent neuron fire. Prolonged exposure to extremely loud noises, such as factory noise or very loud rock music, can cause nerve deafness. The aging process or excessive reliance on certain drugs may also contribute to this problem. Zimbardo and his colleagues (1981) suggested that hearing loss could sometimes lead to paranoid behavior, especially if the person were unaware of the loss. If you cannot hear what others are saying, you might think they are whispering behind your back and thus become suspicious of everyone. |
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