| Hearing loss is prevalent in modern societies as a | | | | individual who has approximately 90 dB or greater |
| result of the combined effects of noise, aging, disease, | | | | hearing loss. The term "hard of hearing" describes a |
| and heredity. Hearing loss is the number one disability in | | | | condition that is less severe than deafness. |
| the world; approximately 28 million Americans suffer | | | | There are many potential causes of hearing loss. |
| some type of hearing loss. In addition, 15 of every 1000 | | | | These can be divided into two basic types, called |
| people under the age of 18 have a hearing loss, and | | | | conductive and sensorineural hearing loss. Conductive |
| nearly 90% of people over age 80 have a hearing | | | | hearing loss is the result of the interference of sound |
| impairment. The incidence of hearing loss is greater in | | | | transmission from the outer ear to the inner ear. |
| men, than women. The sad part is, that hearing loss is | | | | Common causes include, inner ear infections, |
| the most preventable disability in the world. | | | | accumulation of fluid in the middle ear, excessive wax, |
| Hearing is a complicated process involving both the | | | | damage to the eardrum by infection or an injury, or |
| sensitivity of the ear, as well as the ability to | | | | otosclerosis. This type of hearing loss is temporary, |
| understand, and interpret the speech. When we hear | | | | and results in a less severe form. |
| sounds, we really are interpreting patterns of air | | | | Sensorineural hearing loss is due to damage to the |
| molecules in the form of waves. . The ear is able to | | | | pathway from the hair cells of the inner ear to the |
| pick up these waves, and convert them into electrical | | | | auditory nerve and the brain. Common causes include, |
| signals that are sent to the brain. In the brain, these | | | | age-related hearing loss, injury to the inner ear hair cells |
| signals are deciphered into meaningful information, such | | | | as a result of trauma or noise, abnormal pressure in |
| as language or music with qualities like volume and | | | | the inner ear, stroke, benign lesions, and brain tumors. |
| pitch. We can characterize sounds in terms of their | | | | This type of hearing loss is more devastating, and is |
| frequency (or pitch) and intensity (or loudness). | | | | usually more permanent. |
| An individual with hearing in the normal range can hear | | | | The successful treatment of hearing loss depends on |
| sounds that have frequencies between 20 and 20,000 | | | | the cause. A bacterial infection of the middle ear can |
| Hertz. Speech includes a combination of low and high | | | | be treated with antibiotics; blockages of the outer and |
| frequency sounds; vowels have lower frequencies and | | | | middle ears can be cleared; damaged eardrums can |
| are easier to hear. Consonants, on the other hand | | | | be repaired surgically; and ossicles affected by |
| have higher frequencies, and are harder to hear. Since | | | | otosclerosis can be replaced with artificial bones. |
| consonants express most of the meaning of what we | | | | Some causes of sensorineural hearing loss can also |
| say, someone who cannot hear high frequency | | | | be improved. For example, an acoustic neuroma can |
| sounds will have a hard time understanding speech. | | | | be removed surgically. |
| Intensity, or loudness, is measured in decibels. A normal | | | | If no cure is successful, a hearing aid for one, or both |
| hearing range usually ranges from 0 to 140 dB. A | | | | ears usually helps, whether the loss is a result of |
| whisper is around 30 dB, and normal conversations are | | | | conductive or sensorineural problems. Many different |
| usually 45 to 50 dB. Sounds that are louder than 90 dB | | | | types of hearing aid are available and an audiologist will |
| can be uncomfortable to hear. A loud concert might be | | | | advise as to which type best suits the needs of the |
| as loud as 110 dB. Extreme sounds that are 120 dB or | | | | individual. |
| louder can be quite painful and can result in temporary | | | | When a hearing aid does not give adequate |
| or permanent hearing loss. | | | | amplification, as with profound deafness, a cochlear |
| Hearing loss can happen in either frequency or intensity | | | | implant can help. This device transmits sound directly |
| or both. The severity of hearing loss is assessed on | | | | into the auditory nerve via electrodes surgically |
| how well a person can hear the frequencies or | | | | implanted into the cochlea. Although the sounds heard |
| intensities most often associated with speech. Severity | | | | tend to be of a buzzing or electronic nature, it can be |
| of loss can best be described as mild, moderate, | | | | very useful when used in combination with lip reading. |
| severe, or profound. Deafness is used to describe an | | | | |