The Different Types of Hearing Loss

Ear Anatomy. Photo © A.D.A.M.

There are many varying degrees and causes of hearing loss. In general, hearing loss is categorized by three basic types depending on the area of the ear or auditory system that is damaged.

Conductive Hearing Loss

Conductive hearing loss is caused by a mechanical problem along the route from noise in the environment to the inner ear. It could be a problem with one of the three small bones collectively called the ossicles (the stapes, malleus, and incus), or other parts of the ear that fail to conduct sound to the cochlea.

Sometimes the ear drum is unable to vibrate sound properly. Conductive hearing loss can also be a result of fluid in the ear, congenital defects, a foreign body stuck in the ear, or even excess ear wax. Conductive hearing loss is often reversible.

Sensorineural Hearing Loss

Sensorineural hearing loss occurs when the inner ear, cochlea or auditory nerve itself is not functioning properly. It can also be caused when tiny hair-like projections inside the ear called cilia, which normally function to transmit sound through the ear, are damaged. This particular type of hearing loss is generally caused by damage from medications, birth injuries, or genetic factors. Less commonly this type of hearing loss can be caused by tumors, too much exposure to loud noises, head injuries, or other types of trauma. Sensorineural hearing loss cannot be corrected.

Mixed Hearing Loss

Mixed hearing loss is a term used to describe hearing loss caused by a combination of both conductive and sensorineural hearing loss.

Signs & Symptoms of Hearing Loss

  • Conversations become increasingly difficult to understand, particularly if there is background noise.
  • Difficulty understanding sound on the television.
  • Fails to respond to name.
  • Frequently asks for conversations to be repeated.
  • Tinnitus, a constant ringing sound in one or both ears.
  • While many sounds may be muted, others seem very loud and can be irritating.

Questions Your Doctor May Ask

  • Do you have a family history of deafness or hearing loss?
  • Do you have difficulty understanding conversations?
  • Do family members complain that you keep the volume on the television too loud?
  • Do you have a constant ringing or buzzing in the ears?
  • Have you been frequently exposed to loud noises at work or recreationally?
  • Do you have a history of ear infections?

Diagnosing Hearing Loss

Conductive hearing loss can often be diagnosed and even treated by an ENT physician. Sometimes an audiologist, a specialist in evaluating and treating hearing loss, is required, particularly in the case of sensorineural or mixed hearing loss.

Your doctor will conduct a physical examination beginning with two tests using a turning fork to discern the source of the deficit (conductive versus sensorineural). The doctor will also visualize the outer ear and then the inner ear and ear drum (also called the tympanic membrane), using an otoscope.

He will be looking for excessive ear wax, foreign bodies that may be stuck inside the ear, infection, and any damage to the ear drum.

An audiologist can conduct a test of hearing tones. For this test, the patient is usually placed in a quiet sound room to ensure that background noise does not interfere with the test. A pair of headphones will deliver a variety of tones in different frequencies and volumes. This helps determine which range of tones and frequencies the patient can hear best. Another part of this test involves an instrument called a bone conductor. A bone conductor is a device that when placed behind the ear transmits sound by vibrating the bones of the ear. The bone conductor is beneficial in helping the audiologist determine what type of hearing loss you have.

Speech tests can also be conducted in a quiet sound room. The audiologist usually leaves the room and a series of words are played on a recording device. You will be asked to repeat the words. Different words will be played at varying tones and volumes.

To test middle ear function, an impedance test is used. The tone test will be repeated yet again while a probe placed in the ear will raise and lower the amount of pressure inside the ear.

Sometimes the results of these tests are charted on an audiogram. An audiogram is a chart which shows the degree of hearing loss in each ear.

Treating Hearing Loss

Treatment of conductive hearing loss involves finding the root of the problem. For example, if there is a foreign body or excessive wax in the ear, it needs to be removed by a professional. Fluid in the ear can be treated with medication or sometimes drained. If any bones in the ear are fractured, they can often be surgically repaired.

There is no cure for sensorineural hearing loss though many promising studies are being done.

Hearing aids are beneficial in the treatment of sensorineural hearing loss. Hearing aids use a microphone, amplifier and speaker to enhance sound and are most helpful for people who have decreased hearing, not those who are deaf. There are many different styles of hearing aids including aids worn behind the ear, in the ear, and in the ear canal. Hearing aids also come in digital and analog. However, only a small percentage of the population who could benefit from hearing aids actually uses them. Many people are afraid of how hearing aids will make them look and the stigma associated with these devices.

People who are deaf or have severe hearing loss can sometimes be treated with a cochlear implant. A cochlear implant is a small electronic device that goes behind the ear (the external portion) and then has another part that is surgically implanted beneath the skin (the internal part). Cochlear implants do not restore normal hearing and are controversial among the deaf community.

The device bypasses damaged parts of the ear and works directly to stimulate the auditory nerve. The auditory nerve sends a signal which is interpreted by the brain as sound. It takes time and practice to learn how to hear with a cochlear implant.

Prevention of Hearing Loss

Sources indicate that hearing loss among young people is on the rise.

This is largely due to the use of personal music players and exposure to loud noises at work or recreationally. Experts recommend turning the volume down and decreasing exposure. Some medications, such as the antibiotic gentamycin, are associated with hearing loss. Some factors, such as inherited hearing loss, cannot be prevented.

Prevalence of Hearing Loss

In 2006, the CDC estimated that 37 million adults had some degree of hearing loss. Three in 1,000 children born in the United States have hearing loss.

Though hearing loss seems to be on the rise, whether due to increased lifespan or other factors technology is quickly advancing to help individuals with hearing loss. The trend of teaching infants sign language has also benefited the deaf community as more Americans are learning this language. Organizations such as the American-Speech-Hearing-Language Association and the National Institute on Deafness and Other Communication Disorders provide valuable information and support to the public.


American Speech-Learning-Hearing Association. Hearing Assessment. Accessed: January 5, 2009.

American Speech-Learning-Hearing Association. Type, Degree, and Configuration of Hearing Loss. Accessed: January 5, 2009.

Centers for Disease Control and Prevention. Hearing Loss in Children Accessed: August 29, 2015.

Hearing Center Understanding Your Hearing Test. Accessed: January 7, 2009.

Medline Plus. Hearing Loss. Accessed: January 7, 2009.

National Institute on Deafness and Other Communication Disorders. Cochlear Implants. Accessed: January 7, 2009.

National Institute on Deafness and Other Communication Disorders. Hearing Aids. Accessed: January 7, 2009.

MedStar Washington Hospital Center. Hearing Loss. Accessed: August 29, 2015.{}

Continue Reading