What are the different types of hearing loss?

A Conductive hearing loss is caused by interference in the transmission of sound to the inner ear. Infants and young children frequently develop conductive hearing loss due to ear infections. This loss is usually mild, temporary, and treatable with medicine or surgery.

A Sensorineural hearing loss involves malformation, dysfunction, or damage to the inner ear (cochlea) or nerve of hearing and is rarely due to problems with the auditory cortex of the brain. The most common type is cochlear hearing loss and this may involve a specific part of the cochlea (inner hair cells or outer hair cells or both). It may be hereditary or may be caused by a number of different situations, but sometimes the cause is unknown. This type of hearing loss is usually permanent.

The degree of sensorineural hearing loss can be mild, moderate, severe, or profound. Sometimes the loss is progressive (hearing gradually becomes poorer) and sometimes unilateral (one ear only).

Because the hearing loss may be progressive, repeat audiologic testing should be done. Sensorineural hearing loss is generally not reversible medically or surgically, but persons with this type of hearing loss often can be helped with hearing aids.

A Mixed hearing loss occurs when both conductive and sensorineural hearing loss are present at the same time.

A Central hearing loss involves the hearing areas of the brain, which may show as difficulty "processing" speech and other auditory information. This is often referred to as "Auditory Processing Disorder" and may be misdiagnosed as a behavioural disorder.