There are many different types of hearing loss that can occur. The most common type of hearing loss is sensorineural hearing loss, also called “nerve”, “cochlear” or “inner ear” hearing loss. The second most common type is conductive hearing loss. Other types of hearing loss include: mixed and central.
Conductive Hearing Loss
Conductive hearing loss occurs when sound is not conducted efficiently through the ear canal, eardrum, or tiny bones of the middle ear. This results in a reduction of the loudness of perceived sound. Conductive losses may result from earwax blocking the ear canal, fluid in the middle ear, middle ear infection, obstructions in the ear canal, perforations (hole) in the eardrum membrane, or disease of any of the three middle ear bones.
A person with conductive hearing loss may notice their ears seem to be full or plugged. This person may speak softly because they hear their own voice loudly. Crunchy foods, such as celery or carrots, seem very loud and this person may have to stop chewing to hear what is being said. All conductive hearing losses should be evaluated by an audiologist and a physician to explore medical and surgical options.
Sensorineural Hearing Loss
As mentioned, sensorineural hearing loss is the most common type of hearing loss. The most common causes of sensorineural hearing loss are age related changes and noise exposure. Sensorineural hearing loss may also result from disturbance of inner ear circulation, increased inner ear fluid pressure or from disturbances within the hearing nerve.
People with sensorineural hearing loss typically report they can hear people speaking, but they can’t understand what they are saying. People with sensorineural hearing loss also complain that "everyone mumbles."
Although sensorineural hearing loss is permanent and there is currently no cure, there are many excellent treatment options for patients with sensorineural hearing loss, such as hearing aids and cochlear implants.
Mixed Hearing Loss
Mixed hearing loss occurs when both a conductive hearing loss and sensorineural hearing loss are present.
Central Hearing Loss
Our outer and inner ears allow us to “hear” sound, but the brain allows us to “understand” sound. Various medical issues can cause our central processing of auditory stimuli to breakdown – thus causing a central hearing loss or also known as an auditory processing disorder. Persons with a central hearing loss can hear sound but have difficulty with understanding or processing the sound that was heard.
When a central hearing loss is suspected, there are specialized auditory processing tests that are used by an audiologist and physician to determine if a hearing loss is due to central auditory processing issues versus a sensorineural hearing loss.