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