Hearing loss is grouped in a variety of ways. The exact part of the auditory system affected determines the classification. The hearing loss may be conductive, senorineural, central, functional or mixed. The starting point in developing a treatment plan is to properly identify the kind of hearing impairment.
Conductive hearing loss
In situations where sound waves are not completely conducted to the interior of the ear through the structures of the outer and middle ear, conductive hearing loss occurs. This is very widespread and can be caused by a buildup of ear wax, an accumulation of fluid in the eustacian tube, which keeps the eardrum from moving properly, a middle ear infection, a perforated eardrum, disease of the tiny bones of the middle ear and other blockages in the ear canal.
Most instances of this type of hearing loss are reversible, presuming there isn’t any permanent damage to the parts of the middle ear, and with treatment the problem usually clears up in a short amount of time. In some cases a surgical procedure can assist in correcting the condition or a hearing aid may be recommended.
Sensorineural hearing loss
This type of hearing loss accounts for more than 90 percent of the cases in which a hearing aid is worn. It is due to damage in the inner ear or to the acoustic nerve, which prevents sound signals from reaching the brain. Also known as retrocochlear hearing loss or nerve deafness, the damage is more often than not irreversible, although advances in modern technology have enabled some previously untreatable cases to be improved.
The most typical factors that cause sensorineural hearing loss are aging, prolonged exposure to noise, issues with circulation of blood to the interior of the ear, fluid disturbance in the inner ear, medications that cause damage to the ear, a small number of diseases, heredity and problems with the auditory nerve.
Hearing aids are adequate for most people that have this sort of hearing loss, but in more severe cases, a cochlear implant may help restore hearing to those individuals for whom a conventional hearing aid is insufficient.
Central hearing loss
Central hearing loss occurs when an issue in the CNS (central nervous system) keeps sound signals from being processed and interpreted by the brain. Affected individuals can ostensibly hear just fine, but cannot understand or interpret what is being said. Many cases involve a problem with the person’s capacity to effectively filter rivaling sounds. For instance, most of us can hold a conversation with traffic noise in the background, but people with central hearing loss have a difficult time doing so.
Functional hearing loss
An infrequent occurrence, functional hearing loss does not have a psysiological explanation. This condition is caused by psychological or emotional condition in which the person’s physical hearing is normal, however they do not seem to be able to hear.
Mixed hearing loss
As suggested by the term, mixed hearing loss is a mixture of multiple types of hearing loss, in this case the combination of conductive and sensorineural hearing loss. Although there are a couple of other types of hearing loss, the combination of these two is most common.