TYPES OF HEARING TESTS
Different types of hearing tests exist to determine if one has a hearing loss and its severity.
Pure-Tone Test: The well-known pure-tone test requires the patient to wear earphones and raise a hand, press a button, or say “yes” each time a beep is heard. The results are a graph or audiogram that show your hearing threshold, the quietest sound the individual can hear at frequencies.
If fluid or wax is blocking the outer or middle ear, the pure-tone test is substituted with a bone conduction test. A bone conductor or bone oscillator (a box that causes the bones of the skull to vibrate in response to tones) is placed behind the ear instead of headphones. Similarly, the results are produced in the form of an audiogram.
Auditory Brainstem Response (ABR) Test: The ABR test tells us how the inner ear, called the cochlea, and the brain pathways for hearing are working. It measures the hearing nerve’s response to sound. Used for children and others who cannot complete a typical hearing test, individuals whose hearing loss symptoms are due to hearing loss in the brain, or newborns, this test is also known as an auditory evoked potential (AEP) test.
Stickers called electrodes are placed on the individual’s head and in front of his or her ears and connected to a computer. The electrodes measure how the patient’s nerves respond to sounds are made through the earphones.
Speech Test: The speech test is similar to the pure-tone test in that the individual lists to sound through headphones. Instead of tones, the patient listens to words, which they must then repeat. The test determines one’s speech reception threshold. This test can be conducted in either quiet or noisy environments.
Middle Ear Test: The middle ear test aims to assess the function of the middle ear by examining how well the eardrum reacts to varying pressure in the ear canal. Hearing ability directly correlates to eardrum sensitivity. There are three types of middle ear tests: Tympanometry (tests how well the eardrum moves using a probe); acoustic reflex measures (records strength of middle ear’s reflex to a loud sound); and static acoustic impedance (measures volume of air in the ear canal to check for a perforated or ruptured eardrum and for fluid behind the eardrum)
Otoacoustic Emission (OAE) Test: The OAE test measures hair cell function. In a person with typical hearing, a small probe inserted into the causes the inner ear to emit tones or clicking sounds, while someone with hearing loss may not produce these sounds. Results are monitored while the patient takes no action.