What to Know About Hearing

Hearing is one of the five senses. It is a complex process which requires both the detection of sound and the ability to attach meaning to that sound. The ability to hear is critical to communication and navigating the world around you.

The human ear is fully developed at birth, capable of responding to sounds ranging from very soft to very loud. Infants respond to sound even before birth.

So, How Do We Hear

The auditory system can be divided into two main sections: the peripheral auditory system and the central auditory system. The peripheral auditory system consists of the outer ear, the middle ear and the cochlea (inner ear). The outer ear includes the external ear (pinna), the ear canal and the eardrum, also known as the tympanic membrane. Sound waves travel through the ear canal, striking the eardrum and causing it to move or vibrate.

The middle ear is the space behind the eardrum that contains the three smallest bones in the human body. This chain of tiny bones is connected to the eardrum at one end and to an opening to the inner ear at the other end. Vibrations from the eardrum cause the bones to move, sending the sound waves to the inner ear.

The inner ear is a fluid-filled structure called the cochlea which contains hair cells. Vibrations passed into the inner ear cause fluid movement, which then stimulates these tiny hair cells. The hair cells generate an electrical signal, which is passed along the auditory nerve into a region of the brain called the auditory cortex. The auditory cortex assigns meaning to the sound.

Anatomy of the Ear

Hearing Loss Causes and Types


Approximately 95% of hearing loss in the adult population is sensorineural in nature. In this type of hearing loss, the problem is due to damage to or degeneration of the inner ear (sensory) or auditory nerve (neural). The most common causes of sensorineural hearing loss are noise exposure, age, and hereditary predisposition. Other causes include drugs toxic to the auditory system, viral illness, disturbance of inner ear fluids, and invasion of the inner ear by excessive temporal bone growth.


Approximately 5% of hearing loss in the adult population is conductive in nature. In this type of hearing loss, the problem is due to mechanical or structural damage to the outer and/or middle ear, resulting in reduced sound transmission to the inner ear. Common causes are impacted wax, perforated eardrum, middle ear infection, otosclerosis (stiffening of the middle ear bones), cholesteatoma, and congenital anomalies. With a conductive hearing loss, it is possible that medical intervention may result in partial or complete restoration of hearing. In these cases, an appropriate medical referral is warranted.


Mixed hearing loss is a combination of sensorineural and conductive hearing loss.

The Impact of Hearing Loss

The inability to respond appropriately to everyday sounds and communicate effectively with others cannot only cause frustration, but may have serious negative consequences. A person with a mild to moderate hearing loss may be at risk without knowing it. Research has confirmed that hearing loss can have adverse effects on your ability to function effectively, as well as a negative impact on several aspects of daily life. Family relationships, enjoyment of social activities, and performance in work settings may all be negatively affected by hearing loss. Hearing loss can also be dangerous if one fails to hear warning signals or understand the doctor’s instructions regarding proper use of medications.

A Hearing Industries Association and National Council on Aging study clearly demonstrated that individuals with untreated hearing loss reported significantly greater feelings of depression, paranoia, anger, and frustration than hearing aid users.

Other recent studies have linked hearing loss to serious health issues, including heart disease, early onset of dementia, and even diabetes. Hearing loss can greatly affect the quality of life for adults and children. Unmanaged hearing loss can have an impact on employment/earning potential, education, and general well-being. The good news is that individuals with hearing loss who use hearing aids report significantly higher levels of involvement in social activities, fewer worries, and more positive social and family experiences.

Rehabilitation of Hearing Loss

If your hearing evaluation reveals hearing loss, your audiologist will work with you to develop a plan to improve your hearing and communication. This consultation will begin with a discussion about your hearing loss, your lifestyle, your listening needs and your budget. This will help determine the technology that is most appropriate for you. It is important for you to understand your hearing loss and what you can expect from hearing aids if they are recommended for you. We are also happy to help you navigate the myriad of marketing, direct mail, and health insurance benefit information related to hearing aids that many consumers report being inundated and confused by.

With a better understanding of you and your hearing loss, your audiologist may also recommend assistive listening devices (ALDs) or hearing assistive technology (HATs) such as captioned or specialized telephones, TV devices, FM systems, remote microphones, and/or audio-loops. These can help you hear better in situations where hearing aids alone may not completely resolve your issue(s) (large groups, lectures, church). Hearing assistive technology can be used alone or with hearing aids.