Audiogram

Hearing tests help detect hearing loss, identify how severe it is, and determine what is causing it. They measure the ability of sound to reach the brain. Sounds are actually vibrations of different frequencies and intensities in the air around us. Air in the ear canals and bones in the ear and skull help these vibrations travel from the ear to the brain where you hear them. By measuring your ability to hear sounds that reach the inner ear through the ear canal (air-conducted) and sounds transmitted through bones (bone-conducted sounds), hearing tests can also determine what kind of hearing loss you have. An audiogram is a graphic record drawn from the results of hearing tests with an audiometer, which charts the threshold of hearing at various frequencies against sound intensity measured in decibels.

Hearing tests may be done:

  • To screen newborns and young children for hearing problems that might interfere with learning, speech, and language development.
  • To screen children and teens for hearing loss.
  • As part of a routine physical examination.
  • To evaluate possible hearing loss in anyone who has noticed a persistent hearing problem in one or both ears or has had difficulty understanding words in conversation.
  • To screen for hearing problems in older adults.
  • To screen for hearing loss in people who are repeatedly exposed to loud noises or are taking certain antibiotics, such as gentamicin or streptomycin.
  • To determine the type and amount of hearing loss.

When preparing for a hearing test, tell your doctor if you:

  • Have recently been exposed to any painfully loud noise or to a noise that made your ears ring. Avoid loud noises for 16 hours prior to having a thorough hearing test.
  • Are taking or have taken antibiotics that can damage hearing, such as gentamicin or streptomycin.
  • Have had any problems hearing normal conversations or noticed any other signs of possible hearing loss.
  • Have recently had a cold or ear infection.

Before beginning any hearing tests, the health professional may check your ear canals for earwax and remove any hardened wax, which can interfere with your ability to hear the words during testing. For tests in which you wear headphones, you will need to remove eyeglasses, earrings or eyeglasses clips that interfere with the placement of the headphones. The headphones are then placed on your head and adjusted to fit. If you are wearing a hearing aid, you may be asked to remove it for some of the tests. Discuss with your doctor any concerns you have about the need for a hearing test or how the test will be done. Complete the medical test information form to help you understand the importance of the test.

Pure tone audiometry uses a machine called an audiometer to play a series of tones through headphones. The tones vary in pitch (frequency, measured in hertz) and loudness (measured in decibels). The health professional will send a tone and reduce its loudness until you can no longer hear it. Then the tone will get louder until you can hear it again. You signal by raising your hand or pressing a button every time you hear a tone. You should respond even if the tone you hear is very faint. The health professional will then repeat the test several times using a higher-pitched tone each time. Each ear is tested separately. The headphones will then be removed and a special vibrating device will be placed on the bone behind your ear. Again, you will signal each time you hear a tone.

Hearing tests are not painful and there are no risks associated with hearing tests.