Hearing problems are classified in a variety of ways. The specific section of the auditory pathway affected is what determines the classification. In this article we supply an introduction to 5 categories – sensorineural, conductive, mixed, central and functional. The initial step in designing a treatment plan is to properly diagnose the kind of hearing loss.
Sensorineural hearing loss
This type of hearing loss is responsible for more than 90 percent of the instances in which a hearing aid is used. Sensorineural hearing loss is the result of damage in the interior of the ear or damage to the acoustic nerve, which keeps sound signals from being transmitted to the brain. Also known as retrocochlear hearing loss or nerve deafness, the damage is for the most part permanent, though advancements in technology have permitted some formerly untreatable cases to be improved.
The most frequent reasons behind sensorineural hearing loss are the aging process, extended exposure to noise, complications with circulation of blood to the inner ear, fluid disturbance in the inner ear, medications that cause damage to the ear, a small number of diseases, genetics and issues with the auditory nerve.
Hearing aids are adequate for the majority of people that have this sort of hearing loss, but in more serious cases, a cochlear implant can help restore hearing to those individuals for whom a typical hearing aid is not enough.
Conductive hearing loss
When sound waves are not sufficiently conducted to the interior of the ear through the parts of the outer and middle ear, conductive hearing loss arises. Conductive hearing loss is rather common and could be caused by a buildup of ear wax, an accumulation of moisture in the eustacian tube, which keeps the eardrum from moving, a middle ear infection, a perforated eardrum, disease of the bones of the middle ear and other blockages in the ear canal.
Most instances of this type of hearing loss are reversible, assuming there isn’t any irreversible damage to the regions of the middle ear, and with treatment the problem usually clears up in a short amount of time. For some patients a surgical procedure can help to correct the problem or a hearing aid may be fitted.
Functional hearing loss
An infrequent situation, this type of hearing loss does not have a psysiological explanation. Functional hearing loss is caused by psychological or emotional problem in which the person’s physical hearing is found to be normal, but they are not able to hear.
Mixed hearing loss
As suggested by the term, mixed hearing loss is a blend of multiple types of hearing loss – conductive and sensorineural hearing loss. Though there are a few other types of hearing loss, the combination of these two is most common.
Central hearing loss
This condition occurs when a problem in the CNS (central nervous system) prevents sound signals from being processed by the brain. Affected individuals can seemingly hear perfectly well, but can’t decode or interpret what the speaker is saying. Numerous cases involve a problem with the person’s ability to adequately filter competing sounds. For instance, the majority of us can have a conversation while there is street traffic in the background, but individuals with central hearing loss have a really hard time with this.