A hearing test provides an evaluation of the sensitivity of a person's sense of
hearing
Hearing, or auditory perception, is the ability to perceive sounds
In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.
In human physiology and psycholog ...
and is most often performed by an
audiologist
Audiology (from Latin , "to hear"; and from Greek , ''-logia'') is a branch of science that studies hearing, balance, and related disorders. Audiologists treat those with hearing loss and proactively prevent related damage. By employing vario ...
using an
audiometer
An audiometer is a machine used for evaluating hearing acuity. They usually consist of an embedded hardware unit connected to a pair of headphones and a test subject feedback button, sometimes controlled by a standard PC. Such systems can also be ...
. An audiometer is used to determine a person's hearing sensitivity at different
frequencies
Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...
. There are other hearing tests as well, e.g.,
Weber test
Weber (, or ; German: ) is a surname of German origin, derived from the noun meaning " weaver". In some cases, following migration to English-speaking countries, it has been anglicised to the English surname 'Webber' or even 'Weaver'.
Notable pe ...
and
Rinne test Rinne may refer to:
People
*Aleksi Rinne (1899–1974), Finnish smallholder and politician
* Antti Rinne (b. 1962), Finnish politician
* Esa Rinne (b. 1943), Finnish athlete
*Fanny Rinne (b. 1980), field hockey midfielder from Germany
* Fred Rinne ...
.
Ear examination
Prior to the hearing test, the ears of the patient are usually examined with an
otoscope
An otoscope or auriscope is a medical device which is used to look into the ears. Health care providers use otoscopes to screen for illness during regular check-ups and also to investigate ear symptoms. An otoscope potentially gives a view of ...
to make sure they are free of wax, that the eardrum is intact, the ears are not infected, and the middle ear is free of fluid (indicating middle ear infection).
Pure tone audiometry
The standard and most common type of hearing test is
pure tone audiometry
Pure-tone audiometry is the main hearing test used to identify hearing threshold levels of an individual, enabling determination of the degree, type and configuration of a hearing loss and thus providing a basis for diagnosis and management. Pur ...
, which measures the air and bone conduction thresholds for each ear in a set of 8 standard frequencies from 250Hz to 8000Hz. The test is conducted in a sound booth using either a pair of foam inserts or supraural headphones connected to an external audiometer. The result of the test is an audiogram diagram which plots a person's hearing sensitivity at the tested frequencies. On an audiogram an "x" plot represents the softest threshold heard at each specific frequency in the left ear, and an "o" plot represents the softest threshold heard at each specific frequency in the right ear. There is also a high frequency version of the test which tests frequencies over 8000Hz to 16000Hz which may be employed in special circumstances.
In-situ audiometry using mobile applications
The availability of stereo headphones and
smartphone
A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...
s or
tablets equipped with sound reproduction systems led to the appearance of new audiologic diagnostic methods which help people identify their degree of
hearing loss
Hearing loss is a partial or total inability to Hearing, hear. Hearing loss may be present at birth or acquired at any time afterwards. Hearing loss may occur in one or both ears. In children, hearing problems can affect the ability to Language ...
without assistance. For users of these
mobile devices
A mobile device (or handheld computer) is a computer small enough to hold and operate in the hand. Mobile devices typically have a flat LCD or OLED screen, a touchscreen interface, and digital or physical buttons. They may also have a physical ...
, there are a number of applications available with a function for
audiometric hearing testing. There are also
hearing aid application
Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory ...
s with a built-in hearing test for making hearing aid adjustments.
In the process of hearing test with specialized applications, initial
hearing threshold
The absolute threshold of hearing (ATH) is the minimum sound level of a pure tone that an average human ear with normal hearing can hear with no other sound present. The absolute threshold relates to the sound that can just be heard by the organis ...
s of perception of tone signals on different frequencies (
audiogram
An audiogram is a graph that shows the audible threshold for standardized frequencies as measured by an audiometer. The Y axis represents intensity measured in decibels and the X axis represents frequency measured in hertz. The threshold of hea ...
) are identified.
Hearing threshold
The absolute threshold of hearing (ATH) is the minimum sound level of a pure tone that an average human ear with normal hearing can hear with no other sound present. The absolute threshold relates to the sound that can just be heard by the organis ...
s, like with traditional
audiometry
Audiometry () is a branch of audiology and the science of measuring hearing acuity for variations in sound intensity and pitch and for tonal purity, involving thresholds and differing frequencies. Typically, audiometric tests determine a subje ...
, and with a special application, are determined on a standard set of frequencies from 125 Hz to 8 kHz. Also, an application can be integrated with a function for testing the relevance of perception of separate sounds and figures of intelligibility in various acoustic conditions
Technically, the hearing test application consists of the following blocks:
* program module-generator of tone signals of the required frequency;
* graphic interface options (for fixing the user's reaction to exceeding tone perception threshold);
* interpreter of test results (text and graphics);
* database with the results of previous examinations and hearing age norms parameters
Hearing test results obtained through the application will be in error as compared to the results of hearing test conducted by an audiologist because of the following reasons:
* the use of specialized calibrated equipment;
* sound-proofing of the room where hearing test is held;
* heterogeneity of parameters of sound-recording systems in smartphones and tablets, and also headphones or headsets;
* noise masking effect of tone signals
Advantages of the audiometry conducted with a specialized application or
hearing aid application
Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory ...
include availability and possibility to do the hearing test without assistance.
Despite possible errors in the results of diagnostics, the undoubted advantages of hearing testing with a special application or
hearing aid application
Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory ...
include the ability to do the hearing test without assistance and the availability of hearing testing.
Scientists suggest that the hearing test using a mobile application can be used to identify hearing pathologies and also for hearing screening tests.
Weber and Rinne
A complete hearing evaluation involves several other tests as well. In order to determine what kind of hearing loss is present, a bone conduction hearing test is administered. In this test, a vibrating
tuning fork
A tuning fork is an acoustic resonator in the form of a two-pronged fork with the prongs (tines) formed from a U-shaped bar of elastic metal (usually steel). It resonates at a specific constant pitch when set vibrating by striking it against ...
is placed behind the ear, on the
mastoid process
The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, t ...
. When the patient can no longer feel/hear the vibration, the tuning fork is held in front of the ear; the patient should once more be able to hear a ringing sound. If they cannot, there is
conductive hearing loss
Conductive hearing loss (CHL) occurs when there is a problem transferring sound waves anywhere along the pathway through the outer ear, tympanic membrane (eardrum), or middle ear ( ossicles). If a conductive hearing loss occurs in conjunction wi ...
in that ear. Additionally, the tuning fork is placed on the forehead. The patient is then asked if the sound is localised in the centre of the head or whether it is louder in either ear. If there is conductive hearing loss, it is likely to be louder in the affected ear; if there is
sensorineural hearing loss
Sensorineural hearing loss (SNHL) is a type of hearing loss in which the root cause lies in the inner ear or sensory organ (cochlea and associated structures) or the vestibulocochlear nerve (cranial nerve VIII). SNHL accounts for about 90% of rep ...
, it will be quieter in the affected ear. This test helps the audiologist determine whether the hearing loss is conductive (caused by problems in the outer or middle ear) or sensorineural (caused by problems in the cochlea, the sensory organ of hearing) or neural - caused by a problem in the auditory nerve or auditory pathways/cortex of the brain.
Hearing in Noise
The Hearing in Noise Test (HINT) measures a person's ability to hear speech in quiet and in noise. In the test, the patient is required to repeat sentences both in a quiet environment and with competing noise being presented from different directions. More specifically, there are four conditions: (1) sentences with no competing noise, (2) sentences with competing noise presented directly in front of the patient, (3) noise presented at 90° to the right of the patient, and (4) noise presented at 90° to the left of the patient. The test measures
signal-to-noise ratio
Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to the noise power, often expressed in deci ...
for the different conditions which corresponds to how loud the sentences needed to be played above the noise so that the patient can repeat them correctly 50% of the time.
Words-in-Noise Test
The Words-in-Noise Test (WIN) uses monosyllabic words presented at seven different signal-to-noise ratios with masking noise - typically speech spectrum noise. The WIN test will yield a score for a person's ability to understand speech in a noisy background. Unlike a pure-tone audiogram, the WIN test may provide a more functional test of a person's hearing in a situation that is likely to occur.
Modified Rhyme Test
The Modified Rhyme Test (MRT) is defined in the American National Standard ANSI S3.2 Methods for Measuring the Intelligibility of Speech Over Communication Systems.
The method consists of 50 sets of six monosyllabic words that differ in initial or final consonant (e.g. not, tot, got, pot, hot, lot or ray, raze, rate, rave, rake, race). The listener is typically presented with one of the words in the couplet preceded by a phrase, "You will mark the word ___". The six words that rhyme are presented to the listener to select what they believe to be the correct answer. The MRT has been extensively used by the US Air Force to test the performance of different communication systems, which often include a noise interference component. If a condition achieves a score of 80% correct responses or better, then that is often an acceptable performance level.
Other
* The audiologist or hearing instrument specialist may also conduct speech tests, wherein the patient repeats the words he or she hears.
* In addition, a test called a
tympanogram
Tympanometry is an acoustic evaluation of the condition of the middle ear eardrum (tympanic membrane) and the conduction bones by creating variations of air pressure in the ear canal.
Tympanometry is an objective test of middle-ear function. It is ...
is generally done. In this test, a small probe is placed in the ear and the air pressure in the ear canal is varied. This test tells the audiologist how well the
eardrum
In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear
The outer ear, external ear, or auris externa is the extern ...
and other structures in the middle ear are working. The ear canal volume indicates whether a perforation in the eardrum (tympanic membrane) may be present. The middle ear pressure indicates whether any fluid is present in the middle ear space (also called "glue ear" or "otitis media with effusion"). Compliance measurement indicates how well the eardrum and
ossicles
The ossicles (also called auditory ossicles) are three bones in either middle ear that are among the smallest bones in the human body. They serve to transmit sounds from the air to the fluid-filled labyrinth (cochlea). The absence of the auditory ...
(the three ear bones) are moving.
* The last test the audiologist may perform is an
acoustic reflex
The acoustic reflex (also known as the stapedius reflex, stapedial reflex, auditory reflex, middle-ear-muscle reflex (MEM reflex, MEMR), attenuation reflex, cochleostapedial reflex or intra-aural reflex) is an involuntary muscle contraction that ...
test. In this test a probe is placed in the ear and a loud tone, greater than 70 dBSPL, is produced. The test measures the reflexive contraction of the
stapedius muscle
The stapedius is the smallest skeletal muscle in the human body. At just over one millimeter in length, its purpose is to stabilize the smallest bone in the body, the stapes or strirrup bone of the middle ear.
Structure
The stapedius emerges from ...
, which is important in protecting the ear from loud noises, such as a person's own speech which may be 90 dBSPL at the eardrum. This test can be used to give information about the
vestibular
The Vestibular (from pt, vestíbulo, "entrance hall") is a competitive examination and is the primary and widespread entrance system used by Brazilian universities to select the students admitted.
The Vestibular usually takes place from Novem ...
and
facial nerve
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of tas ...
s and indicate if a lesion may be present.
References
External links
Online Hearing Test(Audiogram-type)
{{Physical exam
Physical examination
Ear procedures
Hearing
Medical tests