How Our Hearing Works

The improved ability to hear has a tremendous impact on the quality of life for both those with hearing loss and their families. Having a good understanding of how your hearing works and knowing your options for the best help available through today's advanced hearing aid technology will help you make the right choice in amplification - and allow you to use your new hearing instruments to their fullest potential.

As sound passes through each ear, it sets off a chain reaction, much like a row of toppling dominoes. First, the outer ear collects pressure (or sound) waves and funnels them through the ear canal. These vibrations strike the eardrum, then the delicate bones of the middle ear conduct the vibrations to the fluid in the inner ear. This stimulates the tiny nerve endings, called hair cells, which transform the vibrations into electro-chemical impulses. The impulses travel to the brain where they are understood as sounds you recognize.

Types of Hearing Loss

A number of conditions can exist that cause a disruption in the hearing process and lead to hearing loss. The two most common types of hearing loss are sensori-neural and conductive.

Sensori-Neural Hearing Loss

Sensori-Neural (or "nerve" hearing loss) results from damage to the hair cells, nerve fibers or both in the inner ear. This is the most common type of hearing loss and is often caused by aging or prolonged exposure to noise. It also can be caused by high fever, birth defects and certain drugs. People with sensori-neural hearing loss can hear speech, but frequently have difficulty understanding it. The problem is usually compounded when background noise is present. Sensori-neural hearing loss is most commonly treated by the use of a hearing instrument, and generally cannot be corrected through surgery or medicine.

Conductive Hearing Loss

Conductive hearing loss typically involves an obstruction in the outer or middle ear, which reduces transmission of sound vibration through air, bone or tissue to the inner ear. Fortunately, many conductive hearing losses can be treated successfully by medical or surgical procedures. Hearing instruments can also successfully treat conductive hearing loss. Persons with both conductive and sensori-neural hearing loss are commonly referred to as having mixed hearing loss. Most of these cases can be helped by either a hearing instrument or surgery.