Glossary of Hearing Terms
Acquired Hearing Loss
Loss of hearing that occurs or develops some time during the lifespan but is not present at birth.
Assistive Listening Devices
An Assistive Listening Device (ALD) is any device that helps you overcome your hearing loss. Usually the term ALD is applied to personal devices that transmit, process, or amplify sound, but usually not used to refer to hearing aids. Term may also refer to alerting devices.
ALDs bring distant sounds directly into your ear and can eliminate background noise. Some people incorrectly believe that ALDs are only for people with very serious hearing losses. It's true that ALDs can be a big help for them, but it's also true that ALDs can help people with milder losses ... even people who don't wear a hearing aid.
Many public accommodations such as theaters, movies, and auditoriums are required by the Americans with Disabilities Act (ADA) to have ALDs to loan to patrons. Many churches now offer ALDs to loan to worshipers.
ALDs can be used without a hearing aid with the "user interface" being a headphone, or earbuds, but they are especially effective when used with hearing aids.
Audiogram
An audiogram is a means of recording the results of a hearing test. It will include a table and a graph for each ear showing how well you could hear sounds at various frequencies. This graph dominates the audiogram and measures the lowest volume that you can hear pure tone signals at different frequencies for each ear.
Audiologist
Health care professional who is trained to evaluate hearing loss and related disorders, including balance (vestibular) disorders and tinnitus, and to rehabilitate individuals with hearing loss and related disorders. An audiologist uses a variety of tests and procedures to assess hearing and balance function and to fit and dispense hearing aids and other assistive devices for hearing.
Auditory Brainstem Response (ABR) Test
Electrodiagnostic test procedures give information about the status of neural pathways. These procedures are used with individuals who are difficult to test by conventional behavioral methods. They are also indicated for a person with signs, symptoms or complaints suggesting a nervous system disease or disorder.
Auditory brainstem response (ABR) is an auditory evoked potential that originates from the auditory nerve. It is often used with babies/young children. Electrodes are placed on the head (similar to electrodes placed around the heart when an electrocardiogram is run), and brain wave activity in response to sound is recorded.
Aural Rehabilitation
Techniques used with people who are hearing impaired to improve their ability to speak and communicate.
Balance Disorder
Disruption in the labyrinth, the inner ear organ that controls the balance system, which allows individuals to know where their bodies are in the environment. The labyrinth works with other systems in the body, such as the visual and skeletal systems, to maintain posture.
Cochlea
Named after the Latin word for snail shell, the cochlea is a coiled, tapered tube containing the auditory branch of the inner ear. The core component is the Organ of Corti, the sensory organ of hearing.
Cochlear Implant
A device that is surgically implanted into the cochlea of the inner ear in individuals with severe to profound hearing losses that do not gain benefit from amplification or hearing aids. This device allows these individuals to perceive sound through the implant.
Conductive Hearing Impairment
A temporary or permanent hearing loss typically due to abnormal conditions of the outer and/or middle ear
Decibel (dB)
A unit of measurement indicating loudness, based on a logarithmic scale. Sound scales are based on either sound pressure level (dB SPL) or hearing level (dB HL).
Ear Wax
Yellow secretion from glands in the outer ear (cerumen) that keeps the skin of the ear dry and protected from infection.
Hearing Aid
An electronic device that is designed to couple to the ear and to amplify and deliver sound to the ear. A basic hearing aid consists of a microphone, amplifier and receiver.
Hearing Loss
A hearing impairment is a decrease in one's ability to hear (i.e. perceive auditory information). While some cases of hearing loss are reversible with medical treatment, many are permanent. Whether temporary or permanent, how severely hearing is compromised not a uniform. In some cases the hearing loss is only mild and or moderate and individuals may not even be aware they are affected. In other cases the degree of deafness is profound and, although vibrations will be sensed.
Hearing loss can also differ in what pitches (frequencies) are affected. Human beings generally are sensitive to even quiet sounds, as long as the sounds are at certain pitches: ranging from about 125 Hz to 8000 Hz. The "human ear" is best tuned to pick up sounds at the same pitches (frequencies) as speech, from about 500 to 4000 Hz. Some people do not hear well throughout this range, but are "hard of hearing" depending on the pitch of the sound (low frequency hearing loss, high frequency hearing loss, mid-frequency or U-shaped hearing loss). Hearing impairment comes from different causes. Most commonly, the ear is affected. Conductive hearing losses involve clogging or abnormalities of the outer or middle ear, and only produce mild or moderate impairment, at worst. Hearing loss due to insensitivity of the inner ear, the cochlea, can also be only mild or moderate but can also be much more severe, even causing complete insensitivity to even the loudest sounds (total deafness). Very unusual hearing impairments involve the auditory portions of the brain.
Inner Ear
The section of the ear that encompasses the cochlea, hair cells and hearing nerve to the brain. If a person has a sensorineural hearing loss, the problem occurs in the inner ear.
Meniere's Disease
Inner ear disorder that can affect both hearing and balance. It can cause episodes of vertigo, hearing loss, tinnitus, and the sensation of fullness in the ear.
Middle Ear
The center section of the ear encompassing the area past the ear drum through the bones of the ear to the cochlea.
Mixed Hearing Loss
A combination of conductive and sensorineural components.
Noise Induced Hearing Loss
Hearing loss caused by exposure to harmful sounds, either very loud impulse sound(s) or repeated exposure to sounds over 90-decibel level over an extended period of time that damage the sensitive structures of the inner ear.
Otitis Media
Inflammation of the middle ear, may result from eustachian tube dysfunction.
Otitis Externa
Inflammation of the outer ear, mainly the ear canal.
Otoacoustic Emissions
Otoacoustic emissions (OAE) are inaudible sounds emitted by the cochlea when the cochlea is stimulated by a sound. When sound stimulates the cochlea, the outer hair cells vibrate. The vibration produces an inaudible sound that echoes back into the middle ear. The sound can be measured with a small probe inserted into the ear canal. Persons with normal hearing produce emissions. Those with hearing loss greater than 25-30 dB do not.
Otolaryngologist
Physician/surgeon who specializes in diseases of the ears, nose, throat, and head and neck.
Otologist
Physician/surgeon who specializes in diseases of the ear.
Otosclerosis
Otosclerosis is a hearing condition in which the stapes in the ear becomes attached to the surrounding bone by an abnormal bone growth. Sound transmission is progressively impaired so that hearing in the affected ear deteriorates.
Ototoxic Drugs
Drugs such as a special class of antibiotics, aminoglycoside antibiotics, that can damage the hearing and balance organs located in the inner ear for some individuals.
Outer Ear
The outer most portion of the ear encompassing the pinna and ear canal.
Postlingually Deafened
Individual who becomes deaf after having acquired language.
Prelingually Deafened
Individual who is either born deaf or who lost his or her hearing early in childhood, before acquiring language.
Presbycusis
Hearing loss related to age.
Sensorineural Hearing Loss
Typically a permanent hearing loss due to disease, trauma, or inherited conditions affecting the nerve cells in the cochlea, the inner ear, or the eighth cranial nerve
Speech-Language Pathologist
Health professional trained to evaluate and treat people who have voice, speech, language, or swallowing disorders (including hearing impairment) that affect their ability to communicate.
Sudden Hearing Loss
Sudden hearing loss (SHL) is defined as greater than 30 dB hearing reduction, over at least three contiguous frequencies, occurring over 72 hours or less. It occurs most frequently in the 30 to 60 year age group and affects males and females equally. Although called sudden, it seems unlikely that hearing loss is abrupt but rather it probably evolves over a few hours.
SHL can affect different people very differently. SHL is usually unilateral (that is, it affects only one ear); and is often accompanied by tinnitus, vertigo, or both. The amount of hearing loss may vary from mild to severe, and may involve different parts of the hearing frequency range. SHL may be temporary or permanent. About one third of people with SHL awaken in the morning with a hearing loss.
Tinnitus
More commonly referred to as "ringing in the ears" or "head noise," has been experienced by almost everyone at one time or another. It is defined as the perception of sound in the head when no external sound is present. In addition to "ringing," head noises have been described as hissing, roaring, pulsing, whooshing, chirping, whistling and clicking. Ringing and head noises can occur in one ear or both ears, and can be perceived to be occurring inside or outside the ear. It can accompany hearing loss. It can exist independent of a hearing loss.
Vertigo
Sensation of motion, often described as objects spinning around a person or the person spinning around the room with the room still. This could be a symptom of a vestibular (balance/inner ear) disorder.
Vestibular System
System in the body that is responsible for maintaining balance, posture, and the body's orientation in space. This system also regulates locomotion and other movements and keeps objects in visual focus as the body moves.