The process of hearing sounds is fairly complex. And, because the ear also plays a role in the body’s balance system, a problem with hearing can be associated with balance problems as well.
When a sound reaches the ears, it hits the outer ear first. This contains the ear canal and houses the ear drum. The sound causes the ear drum to vibrate. These vibrations are then picked up by three tiny bones, called ossicles, that are connected to the ear drum. The ossicles are located in the middle ear, and they, in turn, create movement in fluid that’s located in the inner ear. As this fluid moves, it causes hair cells in the inner ear to send electrical signals to the body’s auditory nerve. This nerve then passes the information along to the brain, where the sound is interpreted and understood.
When hearing loss occurs, it can happen in a number of ways and for a variety of reasons. Some children are born with hearing problems, whereas others acquire them over time because of a head injury, noise exposure or an infection. Some medications can also cause hearing loss.
The type of hearing loss a person experiences is typically categorized based on the part of the ear that is affected. For example, conductive hearing loss refers to a problem with the ear canal, ear drum or ossicles in the outer or middle ear. When the inner ear is affected, this is known as sensorineural hearing loss. There's also mixed hearing loss, which is a combination of problems in the different parts of the ear. Though conductive hearing loss can often be corrected medically or surgically, sensorineural and mixed hearing loss are typically more difficult to treat. Hearing problems are often treated by a health care professional known as an audiologist.
SOURCES: American Speech-Language-Hearing Association