Hearing impairment is a disability that consists of either complete or partial ability of someone detecting or understanding sounds. Hearing impairment can be caused by various environmental and physical factors and it may happen to any individual or organism that perceives sound.
Hearing impairment always exists when an individual is not sensitive to the sounds that are normally heard by same individuals of its kind. Hearing impairment can be categorized in terms of how much louder a sound can be made above the average levels for the individual to detect it. An individual is said to be in a condition of profound deafness when even the loudest noises that are produced by devices used to measure sound cannot be detected.
Conductive hearing loss is a condition that occurs when conduction of the sound through the outer or middle ear is not carried out properly. This type of impairment is considered to be moderate to mild because sounds can still be heard by the middle ear. Conductive hearing loss is caused by; ear canal obstruction, inner ear abnormalities, middle ear abnormalities or due to otosclerosis.
Sensor neural hearing loss is caused by lack of sensitivity in the inner ear or impairment of the auditory nervous system. It can be severe enough to a point of leading to total deafness. This kind of hearing loss may be caused by disorders in the hair cells of Corti which is found in the cochlea.
The major causes of deafness include long-term exposure to environmental noise; this is a caused by external noises, the U.S EPA has set a level of 70 dB (A) for a period of 24 hour exposure to be the level expected to protect the public from losing their hearing ability and suffering from other effects of noise like learning detriment and disturbance during sleep.
Hearing loss may also be inherited by the existence of dominant and recessive genes that are able to cause mild or profound hearing impairment. In this case if a family is known to have a dominant gene for deafness, then this gene continues across generations because it manifests itself in the children of the following generations even if it is just from one parent.
The other factor that may lead to deafness is diseases; some diseases like measles and meningitis can cause damage to the auditory nerve hence leading to deafness. Currently autoimmune disease has been identified as a cause of cochlear damage although it’s rare. (www.eeoc.gov).
There are medications that are responsible for causing irreversible damage to the ear; an example of this is the amino glycosides and aspirin. Physical trauma may also cause hearing impairment, this may be as a result of; damage to the ear or the brain parts that process the information conveyed by the ears, head loss or exposure to very loud noise.
The severity of hearing loss is measured by determining the degree of loudness in decibels that a sound should attain before it is detected by an individual. The following are the levels of hearing loss and the corresponding ranges of decibel:
Mild, this ranges between 20 and 40 dB(decibels), moderate hearing loss ranges between 41 and 55 decibels, moderately severe is between 56 and 70 decibels, severe is between 71 and 90 decibels and profound hearing loss is 90decibels and above.
The age at which deafness occurs is important in acquiring the spoken language.
If the hearing loss occurs at an early age then acquiring spoken language and social skills may be a problem for the individual. Hearing aids that are meant to amplify the incoming sound can solve most of the problems caused by hearing impairment but are seen as insufficient and this has led to Cochlear implants that stimulate the hair cell nerves artificially through provision of an electric impulse responsible for the firing of the hair cells. This method is quite expensive and it also requires advanced programming for it to be effective.
As part of the rehabilitation process to those people who have developed hearing problems it is necessary to give the support and technical adaptations (Marschark, 1997). The interview shows that implants are useful in treating mild to profound hearing loss when the defect came before the individual had acquired language and social skills.
The challenges facing deaf people who lose their hearing capacity later in life are that they may have to adapt the use of implants or hearing aids and also they are met with the challenge of having to develop reading and speaking skills. Another challenge is in the use of telephones; the affected person may need to use an interpreter or relay services to use a phone. Depression and loneliness is a problem for the deaf due to isolation and the difficult in accepting the disability.
Hearing problems have also led to break up of many relationships due to lack of communication or miscommunication between family members. Loss of hearing ability is mainly associated with old age and therefore most people opt not to have the hearing aids for the fear that they might look old. The other challenge is that a deaf child must avoid sports which may cause head injury leading to a more serious problem.
The other treatment of deafness is gene therapy. This is a research that has been done on mice and guinea pigs, it involves the re-growth of cochlear hair cells so as to attract neuronal processes that can restore the hearing ability, it is hoped that this will be possible one day on humans. (BBC, On-line news)
The interview indicated that most deaf people prefer eating meat, fruits and desserts. The interview indicated that most deaf people do not like eating a lot of vegetables as compared to the hearing community. Generally deaf people require a normal diet just like the hearing community.
Nutritionists have argued that a deaf person has no difference with a hearing person apart from their hearing capacity and so deaf people deserve the same diet though with lots of protein to encourage the growth of their hair cells. People with hearing impairment face the following problems in their health; the doctors do not look at them when they are explaining their health status, some doctors generally refuse to accept that the patient cannot hear and other doctors refuse to write things down for the deaf patients.
The life span of most deaf people was found to be lower than that of the hearing community; this could have been due to the kind of depression they live with due to isolation from the rest of the community. The eating behavior of the deaf people was found to have an impact on their health (. Glickman and Sanjay, 2003)
http://www.eeoc.gov/facts/deafness.html Hearing impairment and the Americans with Disabilities Act
Marc Marschark, (1997), Psychological development of deaf children, Reprinted Edition, Oxford university press, 1997
Mental Health Care of Deaf People: A Culturally Affirmative Approach, By Neil S.Glickman and Sanjay Gulati; Mahwah,
New Jersey, Lawrence Erlbaum Associates, 2003, 431 pages, $89