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