What is it?
By conducting a hearing test, the Audiologist records your thresholds for each frequency. From low frequency (bass tones or low pitch tones) to high frequency (treble or high pitch tones), the Audiologist presents varying intensities (loudness levels) to record the minimal intensity at which you hear each tone. The minimal intensity is plotted on an audiogram. Typically, the tones range from 250 Hertz to 8,000 Hertz. If the Audiologist is conducting “high frequency hearing testing,” the tones will range up to 12,000 Hertz. The audiogram is typically recorded on a graph which shows the right ear thesholds as red circles, and the left ear thresholds as blue “x” marks.
How it is performed
The hearing test should be done inside of a sound-proof room. Otherwise, ambient noise will interfere with the testing, and your thresholds will not be accurately recorded.
Listening through headphones or insert earphones, you will push a button each time you hear, or think you hear, a pure tone. Each threshold will be checked three times for accuracy. The Audiologist will present the tones in ascending loudness (going from softer to louder), and in descending intensity (going from louder to softer) levels to “bracket” your threshold.
After the pure tone testing, speech testing called Speech Reception Threshold (SRT) will be done. The SRT testing is done to confirm the validity of the pure tone test results. If the levels match, the validity is good. If the levels do not match, further testing or retesting is called for. After the SRT testing is done, typically Word Recognition (WR) testing will be performed. WR testing is done to verify symmetry and to determine if you have “distortion” in your ears. If you have a poor test score during WR testing, it may be consistent with a severe to profound high frequency hearing loss. Asymmetric WR in the presence of symmetric pure tones indicates a medical condition which will be checked by your Ear, Nose, and Throat specialist.
Tympanometry:
What is it?
Tympanometric testing records the integrity of your eardrum, your eustachian tube, and the middle ear space. By fluctuating the air pressure, the response of the eardrum is measured and plotted on a graph.
How it is performed
An air-tight seal is achieved using an ear tip on the tympanometer. You will feel a momentary change of pressure in the ear accompanied by a low frequency hum.
How long does it take?
The test takes several seconds in each ear. It is painless.
Acoustic Reflex Thresholds:
What is it?
By presenting a loud stimulus, the contraction of the stapedius muscle is measured. The level at which the response occurs is recorded.
How it is performed
With the air-tight seal in your ear, you will hear beeps which become louder. Whenever the stapedius muscle contracts, the loudness progression will stop. The equipment is automatic, and the contraction of the muscle is automatic. You will simply stay still while testing is occurring.
How long does it take?
The test takes several seconds in each ear. It is painless.
Distortion Product Otoacoustic Emissions (DPOAE)
What is it?
Inside of the cochlea, the outer hair cells respond to sound stimuli. The response is automatic, and is too soft to hear with the human ear. Therefore the machine will record the response.
How it is performed
The test is automatic. With an air-tight seal in the ear, sound will be presented into the ear. The machine will automatically detect and record the response from the outer hair cells. You will need to be quiet during the testing. The level of the response is documented.
How long does the group of tests take?
A complete diagnostic audiological evaluation takes about 30 minutes. If the tester is new or still learning, the test can take up to two hours. Following the test, the Audiologist will print the results and review with the patient.