Terms Related to Hearing
Auditory Steady State Response (ASSR): A hearing test that measures and records the brain’s response to sound. This test is similar to the ABR test described below. ASSR may provide more accurate frequency information about a profound hearing loss at an earlier age than is possible with an ABR.
Auditory Brain Stem Response (ABR): A hearing test that measures and records the brain’s response to sound. During the test, small electrodes are placed on the baby’s head and a computer is used to measure the brain’s response to sound. The ABR shows if sounds are moving through the brainstem toward the brain. The test does not hurt and is most often done while the baby is sleep-ing. The screening version may be used before the baby leaves the hospital. There is a longer version that is usually one part of a complete diagnostic audiological evaluation for infants and young children. The test may also be used with adults under certain circumstances.
Acquired Hearing Loss: Hearing loss that is not present at birth.
Amplification: The use of hearing aid s or other electronic devices to increase the loudness o f a sound so that it may be more easily received and understood.
Assistive Alerting and Communication Devices: Term used to describe equipment or systems that are available t o help people who are deaf or hard o f hearing increase, maintain, or improve communication and independent functioning within their environment and society. Some of these devices include: wireless personal pagers, videophones, computer IP relay and chat through instant messaging, TTY/TDDs, telephone amplifiers, alerting systems, vibrating alarm clocks, watches and pagers and flashing light smoke detectors.
Audiogram: A graph on which a person’s ability to hear sounds of different pitches (frequencies) at various levels of loudness (intensities) is plotted. The numbers across the top show pitch, from low on the left to high on the right. The numbers going from top to bottom of the audiogram on the left side show the level of loudness.
Audiological Evaluation: Tests conducted by a licensed audiologist to determine whether a hear-ing loss is present, what tones (pitches) are affected, how severe the hearing loss is, and what type of hearing loss it is. The evaluation also includes recommendations for the best way of dealing with the hearing loss. If a hearing aid is recommended, procedures to determine the best hearing aid may also be part of this evaluation.
Audiologist: A licensed health care professional who holds a degree in audiology and is a specialist in testing hearing and in other areas of hear ing services including hearing aid evaluation and recommendations for follow-up services. A pediatric audiologist is one who specializes in the assessment of infants. A habilitative audiologist is one who specializes in therapy for those with hearing loss. There are no separate licenses for these types of specialization.
Auditory Nerve: This nerve is referred to as the VIIIth (eighth) cranial nerve. It is located in the inner ear and leads to the brain. It is responsible for carrying nerve impulses, resulting from sound stimulation, to the brain.
Auditory Neuropathy/Auditory Dyssynchrony (AD/AN): A disorder of the auditory system resulting from inefficient processing of the auditory signal (sound) somewhere between the inner hair cells in the cochlea and the brain. Research is still being done on this disorder and varying terms are used to describe the condition. These terms include: auditory neuropathy, auditory dyssynchrony, and neural hearing loss. The condition is diagnosed using information from a recommended diagnostic audiologic test protocol (group of specific tests) including otoacoustic emissions and auditory brain stem response. A child with AD/AN may not respond to sound in a typical way and the ability to understand speech clearly may be affected. Treatment options are highly individualized.
Aural Habilitation: Therapy designed to help a person who has a hearing loss make more effective use of his/her remaining (or residual) hearing. This therapy may be done by licensed audiologists or speech-language pathologists who specialize in this area. A certified teacher of the deaf/hard-of-hearing may also provide aural habilitation therapy.
Behavioral Observation Audiometry (BOA): During this type of audiometry, an audiologist assesses a young child’s response to sound through observation of the child’s facial expression, body movements and other behavioral responses. A variety of sounds from high pitch (frequency) to low pitch may be presented at various levels of loudness (intensity). This test is only one part of a complete audiological evaluation.
Bilateral Hearing Loss: A hearing loss of any degree which is in both ears.
Binaural Hearing Aids: Hearing aids worn on both ears.
Bone Anchored Hearing Aid (BAHA): Surgically implanted bone conduction hearing aid. Sound is picked u p by a microphone o n the external processor, transmitted to a titanium implant placed in the mastoid bone, and conducted through the bone to the inner ear. The BAHA may be one option for a child or adult who cannot wear traditional hearing aids due to physical differences in the structure of the outer or middle ear.
Bone Conduction: The process through which sound is transmitted to the inner ear by the vibration of the bones of the skull in response to sound. During a bone conduction hearing test, a vibrator is placed on the skull in back of the ear. Vibrations of sound are carried through the bone, bypass-ing the outer and middle ear, allowing for testing of the inner ear directly. This test may be one part of a complete audiologic evaluation.
Bone Conduction Hearing Aid: Functions much the same as a traditional hearing aid except sound is transmitted through a wire to a bone oscillator (vibrator) placed on the mastoid bone behind the ear and held in place by a headband. The oscillator vibrates with sound waves and sound is carried through the bone to the inner ear. This may be one option for a child who cannot wear traditional hearing aids due to physical differences in the structure of the outer or middle ear.
Cochlea: The name for the inner portion of the ear, which in a typical ear, contains the hair cells responsible for transmitting sound via the auditory nerve to the brain.
Cochlear Implant: An electronic device that stimulates nerve endings in the inner ear (cochlea) in order to receive and process sounds, including speech. A microphone, a speech processor (miniature computer that changes sound waves into special code d signals), and a transmitter (coil that sends coded signals to internal parts) are worn externally. A small receiver (changes coded signals into electrical pulses) and an electrode array (carries decoded electrical impulses to the hearing nerve) are surgically implanted.
Conditioned Play Audiometry: During this type of audiometry the audiologist measures a young child’s response to sound through the use of a structured game. For example, the child may be taught to drop a block in a container whenever a sound is heard. A variety of sounds from high pitch (frequency) to low pitch may be presented at various levels of loudness (intensity). This test is only one part of a complete audiological evaluation.
Conductive Hearing Loss: A type of hearing loss caused by partial or complete blockage of the outer or middle portions of the ear. This blockage prevents sound waves from reaching the inner ear through the normal route. In children, this type of hearing loss is typically medically correctable and is often associated with otitis media.
Congenital Hearing Loss: Hearing loss present at birth or associated with the birth process, or which develops within the first few days of life.
Connexin 26: A protein that plays an important role in the functioning of the cochlea. The instructions for this protein are found in many genes including one known as the GJB2 gene. Gene tic research indicates that a significant number of newborns with hearing loss who do not have a syndrome, may have a variation in the GJB2 gene. (See genetic hearing loss.)
Deaf: Medically or clinically, a hearing loss so severe that a child is unable to understand or process language information through hearing alone. Culturally, the term (with a capital letter “D”) Deaf refers to the cultural heritage and community of individuals who a re deaf. ( See Deaf Culture and Deaf Community.)
Decibel: The unit of measurement for the loudness of a sound. The higher the dB level presented, the louder the sound. In describing a hearing loss, the higher the dB level indicated, the more severe the hearing loss.
Earmold: An individually fitted plastic or vinyl piece which is worn in the outer ear and connects with a hearing aid. It has a channel which carries sound from the hearing aid to the ear.
ENT: A medical doctor who specializes in the treatment of the ears, nose, and throat and is some-times referred to as an otolaryngologist or otologist.
Etiology of Hearing Loss: The cause of the hearing loss.
Feedback: The whistling sound made when amplified sound goes back into the microphone. In a hearing aid, feedback can occur when an earmold does not fit well and the amplified sound goes back into the hearing aid microphone. There are additional causes for feedback and persistent feedback should be discussed with your parent advisor or audiologist.
Frequency Modulation (FM) System: An assistive listening device used to reduce the problem of background noise interference and/or distance between the speaker and the person with the hearing loss. Increasing the loudness of speech relative to background noise is also ref erred to as improving the signal to noise ratio. One type of FM system consists of a microphone/transmitter (worn by the speaker) and a receiver (worn by the child). The signal is transmitted from the speaker to the child via an FM signal. FMs are used in school settings and increasingly in homes where families use them to give their babies and young children more consistent language and speech experiences.
Frequency: The number of vibrations per second of a sound. Frequency, expressed in Hertz (Hz) determines the pitch of the sound. Lower Hz numbers are low pitched sounds; higher Hz numbers are high pitched.
Functional Hearing: Term that describes the usefulness of a person’s residual (remaining) hearing, when amplified with hearing aids, to hear and understand information through audition only.
Gain: Term that describes the amount of amplification provided by a hearing aid. For example, a child with unaided hearing at 70 dB who, when amplified, hears at 30 dB, is experiencing a gain of 40 dB.
Genetic Hearing Loss: Hearing loss that is caused by one of more than a hundred genes that are known to be responsible for hereditary hearing loss and deafness. The hearing loss can be part of a syndrome (meaning the baby has other problems) or non-syndromic (meaning that the baby has no other problems).
Hard of Hearing: Medically or clinically, a hearing loss, whether permanent or fluctuating, which affects a person’s ability to detect or understand some sounds including speech. The term preferred by the Deaf and Hard of Hearing community over the term “hearing impaired” when referring to individuals who have hearing loss and also have and use residual hearing for communication purposes.
Hearing Aid: An electronic device that amplifies sound and directs it into the ear. A hearing aid consists of a microphone, an amplifier (makes the signal louder), and a receiver (loudspeaker). Sound usually enters the ear through an ear mold worn in the ear. The most common style of hearing aid for children is a behind-the-ear hearing aid in which the hearing aid fits behind the top and back part of the ear and connects via a small tube to the ear mold. See also bone conduction hearing aid and bone anchored hearing aid.
Hearing Screening: A pass/refer type of hearing test designed to identify infants or children who require additional audiological evaluation to rule out or confirm the presence of a hearing loss.
Hearing Loss: A term used to describe a level of hearing less than that typically heard by the general population. The range of hearing loss is characterized as shown below. The range of numbers attached to the specific word labels may vary slightly.
- Normal Hearing 0 dB to 15 dB
- Mild Loss 16 dB to 35 dB
- Moderate 36 dB to 50 dB
- Moderate/Severe 51 dB to 70 dB
- Severe Loss 71 dB to 90 dB
- Profound 91 dB or more
Hearing Impaired: Clinical or medical term used to describe a person whose hearing is less than the normal range. It is not the term generally preferred by individuals who have a hearing loss. (See deaf, hard of hearing.)
Huggies: The brand name of a plastic-ringed device designed to “hug” the hearing aid to the ear. Huggies are popular for infants and toddlers whose ears may not hold the hearing aid snugly in place behind the ear.
Intensity: The loudness of a sound, measured in decibels (dB).
Listening Age: Term used to describe how long a child has worn a hearing aid and thus had the opportunity to “listen”. For example, after a child has worn a hearing aid for 1 year, his listening age will be 1. A child with a listening age of 1 might be just beginning to use words even though his chronological age may be older.
Mixed Hearing Loss: A type of hearing loss that has both a conductive and a sensorineural component. (See conductive and sensorineural.)
Monaural Amplification: The use of one hearing aid instead of two.
Otitis Media: A medical term for a middle ear infection. Children who have recurring otitis media may experience fluctuating hearing loss and may be at risk for speech-language delays. Fluid may be present with or without infection, and may cause temporary hearing loss, which can evolve into permanent hearing loss.
Otoacoustic Emissions (OAE )Test: A hearing test that is used to verify the function of the cochlea (part of the inner ear). During the test a small device (probe) is placed in the baby’s ear and a computer records the response. The test is very simple and does not hurt. An OAE test is often done as one type of hearing screening test before the baby leaves the hospital. It should be done as part of a complete diagnostic audiological evaluation for infants and young children.
Otologist: A physician who specializes in medical problems of the ear (See ENT).
Progressive Hearing Loss: A hearing loss that increases over time.
Real Ear Measurement: An audiological test that measures how effectively sound is amplified by the hearing aid for an individual child. During this test a small device (probe microphone) is placed in the ear canal while the hearing aid and ear mold are being worn.
Residual Hearing: The term used to describe the amount of usable hearing present in a person who has a hearing loss.
Sensorineural Hearing Loss: Hearing loss due to abnormal inner ear/cochlear (sensory) or cochlear nerve (neural) function. Advances in testing and imaging techniques have made it possible, in most cases, to distinguish between sensory and neural, though the term sensorineural remains the most common description of this type of permanent hearing loss. The majority of losses that fall into this category are sensory in nature.
Speech Awareness Threshold (SAT): This is the faintest level at which an individual can detect the presence of speech 50% of the time during an audiologic evaluation.
Speech Reception Threshold (SRT): This is the faintest level at which an individual correctly identifies 50% of the words from a list of specific two syllable spoken words during an audio logic evaluation.
Speech Area or Zone: On an audiological graph, displayed in decibels and frequencies, the area in which most conversational sounds of spoken language occur. This area is called the “speech banana” because of the shape this area forms on the graph. One purpose of wearing hearing a ids is to amplify sound into the speech area. This is not possible with all types or amounts of hearing loss.
Tympanometry: This test is used to measure the movement of the eardrum. It is not a test of hear-ing but provides information on how well the ear canal, eardrum, eustachian tube, and middle ear bones a re working an d on t he ability of the middle ear to conduct sound to the inner ear. Tympanometry is important as one part of a complete audiological assessment because temporary conditions of the middle ear may effect interpretation of other tests. It is also useful to the otologist in determining whether a middle ear problem, possibly requiring medical treatment, exists.
Threshold: This is the faintest level at which an individual can hear a sound (usually a tone) 50% of the time that it is presented.
Unilateral Hearing Loss: A hearing loss of any degree in only one ear.
Visual Reinforcement Audiometry (VRA): During this type of audiometry, an audiologist measures a young child’s response to sound through observation of the child’s conditioned response to a pairing of light and sound. For example, the audiologist pairs the presence of a sound that the child can definitely hear to the action of a toy that lights up and moves. When the child has learned to look toward the toy when a sound is heard, a variety of sounds from high pitch (frequency) to low pitch may be presented at various levels of loudness (intensity). This procedure is only one part of a complete audiological evaluation.