What is the Hearing Test (Audiometry)? What are the Types of Hearing Tests?
The Hearing Test, also known as Audiometry, is a diagnostic procedure used to evaluate a person’s ability to hear sounds. It is a crucial test for identifying hearing loss and determining the extent and type of hearing impairment. Audiometry is performed by an audiologist or a hearing healthcare professional using specialized equipment in a soundproof room.
There are several types of hearing tests that can be conducted during an audiometry evaluation. These tests help in assessing different aspects of a person’s hearing abilities. Let’s explore some of the common types of hearing tests:
1. Pure-tone Audiometry: This is the most basic and common hearing test. It measures a person’s hearing sensitivity to different frequencies or pitches of sounds. The individual wears headphones and is asked to respond when they hear a tone at various volumes and frequencies. The results are plotted on an audiogram, which shows the person’s hearing thresholds at different frequencies.
2. Speech Audiometry: This test evaluates a person’s ability to hear and understand speech. It measures the individual’s speech reception threshold (SRT), which is the lowest level at which they can understand speech, and their word recognition score (WRS), which determines how well they can identify and repeat words. Speech audiometry helps in assessing the clarity and understanding of speech in different listening conditions.
3. Tympanometry: Tympanometry assesses the movement of the eardrum (tympanic membrane) and the middle ear. It measures the compliance of the eardrum in response to changes in air pressure. A small probe is inserted into the ear canal, and air pressure is varied while a tone is played. Tympanometry helps in identifying problems such as fluid in the middle ear, eardrum perforation, or issues with the middle ear bones.
4. Otoacoustic Emissions (OAEs): OAEs are sounds generated by the inner ear in response to a sound stimulus. This test measures the presence and strength of these emissions to assess the health of the cochlea, the sensory organ responsible for hearing. OAEs are particularly useful in testing newborns and infants who may not be able to respond to traditional audiometry.
5. Auditory Brainstem Response (ABR): ABR measures the electrical activity of the auditory nerve and brainstem in response to sound. Electrodes are placed on the scalp, and the person listens to a series of clicks or tones. ABR is often used to test the hearing of infants, young children, or individuals who are unable to participate in traditional audiometry. It can help identify hearing loss and determine the site of the problem along the auditory pathway.
6. Bone Conduction Testing: This test evaluates the hearing sensitivity of the inner ear by bypassing the outer and middle ear. A bone oscillator is placed behind the ear, and vibrations are transmitted directly to the cochlea. Bone conduction testing helps in differentiating between conductive and sensorineural hearing loss and determining the type and degree of hearing impairment.
7. Speech-in-Noise Testing: This test assesses a person’s ability to understand speech in noisy environments, which is a common challenge for individuals with hearing loss. It measures the signal-to-noise ratio required for the person to understand speech accurately. Speech-in-noise testing helps in determining the person’s ability to communicate effectively in real-life listening situations.
These are just a few examples of the various types of hearing tests that can be conducted during an audiometry evaluation. The specific tests performed depend on the individual’s age, symptoms, and suspected hearing issues. The results of these tests provide valuable information for diagnosing hearing loss, determining the appropriate treatment options, and fitting hearing aids or other assistive devices. It is essential to undergo regular hearing tests to monitor any changes in hearing abilities and address any hearing-related concerns promptly.