The first major step toward identifying and managing hearing loss is to have your hearing tested by an audiologist. Have you ever wondered what all that entails?
Audiology is so much more than those simple screenings you had back in grade school. Despite being tiny, the hearing mechanism is incredibly complex, and evaluating it requires many different tests—a “battery” of tests that analyze distinctive aspects of your hearing.
If you ever notice a problem with your hearing or balance, it’s important to schedule an appointment as soon as possible. Additionally, if you’re over the age of 50 and have never had an audiological evaluation, it’s a good idea to get yourself scheduled so you can establish a baseline for your hearing as you grow older.
So, who are audiologists, and what types of tests will they perform with you? In this article, we’ll look at a possible patient journey through the hearing and balance evaluation process, but first, let’s look at some of the fundamental characteristics of audiology.
Audiology: The Basics
Audiologists are autonomous professionals who diagnose and treat individuals with auditory, balance, and related disorders. They have master’s and/or doctoral degrees in audiology (Au.D.) from regionally accredited universities and, in most states, a specific audiology licensure, certification, or registration.
An audiologist’s scope of practice is defined by the training and knowledge base of professionals who are licensed and/or credentialed to practice. It includes the audiologic identification, assessment, diagnosis, and treatment of individuals with impairment of auditory and vestibular function, prevention of hearing loss, and research.
Identification, Assessment, and Diagnosis
Using standardized testing procedures and appropriately calibrated instrumentation, audiologists administer behavioral, psychoacoustics, and electrophysiologic tests to measure aspects of patients’ peripheral and central auditory systems. When assessing the vestibular system—the one responsible for informing the brain on motion, head position, and spatial orientation—they run behavioral and electrophysiologic tests of equilibrium (balance). Once all testing is finished, audiologists assess and interpret the results, leading to the diagnosis of hearing and/or vestibular abnormality.
Serving patients of all ages, audiologists provide the full range of audiologic treatment services for persons with impairment of hearing and vestibular function.
Audiologists also design, implement, and coordinate industrial and community hearing conservation programs. These include the identification and improvement of noise-hazardous conditions, identification of hearing loss as well as counseling on use of hearing protection, employee education, and the training and supervision of non-audiologists performing hearing screening in the industrial setting.
Intraoperative Neurophysiologic Monitoring
Audiologists administer and interpret electrophysiologic measurements of neural function, including but not limited to sensory- and motor-evoked potentials, nerve conduction velocity, and electromyography. These measurements are used in differential diagnosis, pre-and postoperative evaluation of neural function, and neurophysiologic intraoperative monitoring of the central nervous system, spinal cord, and cranial nerve function.
Research is a key part of the job as well: Audiologists design, implement, analyze, and interpret the results of research related to auditory and balance systems.
What to Expect as a Patient
Generally speaking, you will be referred to an audiologist after presenting a hearing and/or a balance issue to your physician. At the start of your appointment, you will be asked questions through which you will present your medical case history. Based on that, your audiologist will decide on the proper tests to use during the evaluation.
For hearing issues, your audiologist will first perform a comprehensive audiologic evaluation to specifically evaluate any auditory disorders, and second, determine the subsequent management tactics based on the assessment’s outcomes. These tactics can come in the form of education on prevention or the need for amplification, such as hearing aids or cochlear implants, based on how profound the hearing loss case is.
Depending on the symptoms and findings, further evaluation may be required to diagnose a balance disorder. Referral to this assessment can come from a variety of sources, such as educators, healthcare professionals, government or private agencies, consumer organizations, and even self-referral.
Finally, just like your other doctors, your audiologists will refer you to other professionals should other steps be necessary.
The Hearing Test
The scope of practice designed by the Joint Committee on Audiology Clinical Practice Guidelines has defined a comprehensive audiometric evaluation to involve:
Equipment and Test Environment
As appropriate, testing is conducted in an environment where ambient noise levels meet current American National Standards Institute (ANSI) standards, ensuring there are minimal distracting sounds that might potentially take away from and impact the test results. In addition, all electroacoustic instruments must meet ANSI standards as well as those set by manufacturers.
Using an otoscope (ear light), your audiologist will conduct an internal inspection of the outer ear, ear canal, and eardrum, looking for foreign bodies and wax that might be causing a blockage. In the process, they will note the color of the ear canal wall, the translucency and color of the tympanic membrane, and the presence, shape, and placement of the cone of light coming from the otoscope.
Pure-Tone Audiometry: Air Conduction
If you’ve ever had your hearing tested in school or at the doctor’s office, you may remember wearing headphones and raising your hand whenever you heard the “beep.” This is pure-tone testing, also called air conduction testing because the sounds go through your outer and middle ear.
Pure-tone tests help determine the quietest sound you can hear at different pitches, or frequencies. A series of tones or beeps will play, and you will be asked to indicate when you can hear them. You will wear a set of over-the-ear or in-the-ear earphones, and the clinician will present tones to one ear at a time\. Your audiologist may have you respond to the sounds by raising a finger or hand, pressing a button, pointing to the ear where you heard the sound, or saying “yes.”
Pure-Tone Audiometry: Bone Conduction
Through this type of testing, your hearing ability can be measured even when there is a problem with the outer or middle ear or when there is a blockage, such as a buildup of wax or fluid. Your audiologist will put a small device behind your ear or on your forehead. The sounds sent through this device cause your skull to vibrate gently, and this vibration goes straight to the inner ear (cochlea), skipping the outer and middle ear.
Speech Audiometry: Word Recognition and Speech Reception Threshold
Different forms of speech testing analyze how well you listen to and repeat words. One such test is the speech reception threshold (SRT), which is specifically designed for older children and adults who can talk.
Once again, you will put on headphones. Your audiologist will say words into the headphones, ask you to speak aloud and repeat back what you hear, and take note of the softest speech you can repeat. This assessment measures your speech and word recognition, and comparing its results with those gained from the pure-tone test helps identify levels of hearing loss.
People with hearing loss often have the most trouble hearing in noisy places. To account for this, you may also need to repeat words that you hear at a louder level, and your speech testing may occur in either a quiet or noisy place.
Acoustic Immittance Tests
Your ear is made up of three parts: the outer, the middle, and the inner ear.
When there is a problem in your middle ear, sounds have trouble making it from your outer ear to your inner ear and brain. Because of this, an important goal of the hearing test is to identify just how well your middle ear is functioning. This part of testing is especially important in children ages 3–5, as young children are more likely to have hearing loss due to middle ear problems, such as ear infections.
This portion of the exam may include:
Tympanometry measures how well your eardrum moves. Your audiologist will put a small probe—which will look like an earphone—into each of your ears, and a small, attached device will push air in. All you must do is sit still.
As you undergo the test, your audiologist will view and analyze a tympanogram, which is a graph created by the testing instrument that indicates whether or not your eardrum moves the correct amount and in the correct way, is too stiff, or has a hole in it. This all helps your audiologist determine if you have middle ear fluid, a hole in your eardrum, or wax in your ear canal. It can also help verify if a child has an ear infection.
Whenever you hear a loud sound, a tiny muscle in your middle ear tightens. This is called an acoustic reflex, and it happens without you knowing it. The degree of sound necessary to cause this reflex can reveal a lot about your hearing and in cases of more profound hearing loss, you may not have any reflex at all.
Much like tympanometry, this test utilizes probes in your ear. Again, you will merely need to sit still as the device emits sounds and records your reflexes.
Additional Specialized Audiometric Tests
Depending on the findings of your audiological evaluation, it may be recommended that you undergo additional tests, such as:
Auditory Brainstem Response (ABR)
Auditory brainstem response testing (ABR) measures your brain wave activity in response to sound. For this test, you do not have to say or do anything. You will simply need to rest quietly, sometimes even sleep.
Your audiologist will attach a collection of electrodes to your head. These electrodes will be connected to a computer, and they will record what your brain does throughout the assessment. When testing is finished, the results can be viewed on a computer printout.
Otoacoustic Emissions (OAE)
Otoacoustic emissions are those sounds produced by the cochlea or inner ear. Therefore, this test measures how well parts of your inner ear respond to sound.
A probe will emit sound into your ear and measure the sound that comes back. As with previously described assessments, you will not need to do anything during testing, and your results will be displayed on your audiologist’s monitor screen.
Additional Hearing Tests
Other potential hearing tests may include:
- Tone Decay looks for retro-cochlear function and measures auditory fatigue using a sustained tone.
- Short Increment Sensitivity Index (SISI) may help to identify the location of auditory dysfunction.
- Stenger is used to confirm the accuracy of the hearing threshold. It can also help determine whether hearing loss is occurring in one ear or both.
- Sometimes, hearing impairment is caused by a disruption in the brain that impacts how a person comprehends sound. This is called Central Auditory Processing Disorder (CAPD), and while it does impact hearing, it is technically not a form of hearing loss. CAPD can be identified through a series of Central Auditory Tests.
- Acoustic Reflex Decay is a middle ear muscle test that measures the strength and length of the reflex.
- A Tinnitus Evaluation utilizes frequency matching and loudness matching to help understand the ringing in your ears and provide recommendations on how to manage and cope with it.
After the Evaluation
Once all testing has finished, your audiologist will review the results and provide you with information regarding your hearing—including the interpretation and documentation of your assessment results—along with practical advice on next steps for managing any loss or conditions you may be experiencing. This may include recommendations for audiologic follow-up or referral and coordination with other services.
It may also be recommended that you enroll in counseling, guidance, or education programs to help with coping and to learn about prevention and hearing conservation. Counseling and education can be given to the patient, family, and/or caregiver.
When in Doubt, Get Tested
Despite this long, exhaustive list of tests, a comprehensive audiometric evaluation typically lasts about 30 minutes. Your situation will likely not involve all of these assessments, as many are only conducted on an as-needed basis.
If you have any worries about your hearing, your ears, or your balance, consider scheduling time with your audiologist. Much of hearing loss treatment and management is preventative, so it’s important to identify issues as soon as possible—and even if you end up not exhibiting signs of hearing loss or any disorder, your exam will inform you on your ear health, giving you peace of mind.
- American Academy of Audiology. (1996). Audiology: Scope of practice. McLean (VA): AAA Publ.
- American National Standards Institute. (1981). Reference equivalent threshold for audiometric bone vibrators [ANSI S3. 1-1977 (R1981)]. New York: Acoustical Society of America.
- American National Standards Institute. (1986). Artificial head bone for the calibration of audiometer bone vibrators [ANSI S2. 1972)]. New York: Acoustical Society of America.
- American National Standards Institute. (1987). Specifications for instruments to measure aural acoustic impedance and admittance (aural acoustic immittance) (ANSI S3-.39-1987). New York: Acoustical Society of America.
- American National Standards Institute. (1991). Maximum permissible ambient noise levels for audiometric test rooms (ANSI S3.1-1991). New York: Acoustical Society of America.
- American National Standards Institute. (1992). Method of manual pure-tone threshold audiometry [ANSI S3.21 1978 (R1992)].
- American National Standards Institute. (1996). Specifications for audiometers (ANSI S3.1996). New York: Acoustical Society of America.
- American Speech-Language-Hearing Association. (1978). Manual pure-tone threshold audiometry. ASHA, 20(4), 297-301.
- American Speech-Language-Hearing Association. (1992). External auditory canal examination and cerumen management. 10. American Speech-Language-Hearing Association. (1997). Preferred practice patterns for the profession of audiology. Rockville, MD: ASHA.