- Acoustic neuroma (vestibular schwannoma) is a slow-growing, benign tumor on the 8th cranial nerve. (See more under Ear Problems.)
- Acoustic reflex is a contraction of muscles in the middle ear that helps reduce the effects of a loud sound.
- Air conduction is how sound waves travel through the ear canal to reach the eardrum.
- Assistive listening device (ALD) is designed to highlight a particular sound, as the voice of a distant speaker.
- Audiogram is a visual graph that displays the range of sounds one is able to hear. (See more under Hearing Tests.)
- Audiologist (See under Hearing Specialists.)
- Auditory brain stem response (ABR) is a measurement of the electrical impulses that are sent from the inner ear to the brain when sounds are heard.
- Aural rehabilitation is provided by an audiologist or speech-language pathologist who focuses on a patient’s adjustment to hearing loss and helps to reduce the difficulties.
- Behind-the-ear (BTE) is a type of hearing aid with a circuitry casing that rests behind the ear. (See more under Hearing Aids.)
- Benign paroxysmal positional vertigo (BPPV) (See Balance Problems.)
- Bone conduction is how sound waves travel through the bones of the skull to reach the inner ear. (See more under Hearing Tests Audiometry.)
- Caloric testis one that involves circulating water through the ear canal. The doctor or audiologist observes the patient’s eye movements as different water temperatures stimulate the inner ear.
- Cerumen is the protective earwax in the ear canal.
- Cochlea is a part of the inner ear that translates incoming sound waves into electrical signals that can be understood by the brain. (See more under Structure of the Ear.)
- Cochlear implant (See more separately.)
- Completely in the canal (CIC) is the smallest type of hearing aid available. (See more under Hearing Aids.)
- Conductive hearing loss results from blockage in the ear canal, a ruptured eardrum, or restriction of the movement of the tiny bones in the middle ear.
- Decibel (db) is a unit of measure that defines sound intensity based on sound pressure level. Decibels also measure how a persons hearing compares with a normal hearing level.
- Dix-Hallpike Test is used to determine whether a condition known as benign paroxysmal positional vertigo (BPPV) is present . (See more under Hearing Tests.)
- Ear canal is an inch-long pathway leading to the eardrum. The ear canal produces cerumen and contains hairs that prevent bacteria and foreign objects from reaching the eardrum.
- Earmold is the earpiece of a hearing aid. It is made to fit into the ear so that it will direct sound toward the eardrum.
- Ear, nose, and throat (ENT) is a specialty physician or otolaryngologist.
- Electronystagmography (ENG) is a battery of tests that evaluate the interaction between the inner ear and the eye muscles.
- Eustachian tube is a narrow channel that connects the middle ear with the nose and throat.
- Feedback is a high-pitched whistle or squeal made when an amplified sound is picked up by a microphone or hearing aid and re-amplified.
- Frequency response is a range of frequencies to which a hearing aid can respond, which is adjusted to the particular degree of hearing loss.
- Glomus jugulare tumor is a very rare, slow growing, and benign tumour that often invades the temporal bone of the middle ear that can interfere with the vibration of the ossicles.
- Hair cells are responsible for hearing. There are two different types: inner hair cells and outer hair cells. Ones within the cochlea convert sound waves into electrical impulses and then carry them to the brain. Hair cells in the vestibular labyrinth respond to motion.
- Hearing aids are devices that amplifies sound and directs it into the ear canal.
- Hearing loss has been defined by scientists who have categorized it into three types: conductive, sensorineural, and mixed. (See more under Introduction.)
- In the canal (ITC) is a type of hearing aid that fits partly in the ear canal but extends to the outer bowl of the ear.
- In the ear (ITE) is a type of hearing aid that fills most of the outer bowl of the ear.
- Meniere’s disease is characterized by attacks of vertigo and hearing loss that is thought to be caused by a fluid imbalance in the inner ear.
- Middle ear is the air-filled cavity between the eardrum and the inner ear. It contains three tiny bones called the ossicles.
- Mixed hearing loss is a combination of both sensorineural (inner ear) and conductive (middle or outer ear) hearing loss.
- Myringotomy is a procedure in which a doctor will make a small incision in the eardrum to equalize air pressure and remove fluid from the middle ear.
- Nystagmus is the involuntary back-and-forth movement of the eyes that may accompany vertigo.
- Ossicle is any of the three tiny bones (hammer, anvil, and stirrup) in the middle ear that vibrate back and forth to transfer sound waves to the inner ear.
- Otitis externa (swimmer’s ear) is an infection of the ear canal, resulting from persistent moisture in the ear and often occurs because of frequent swimming.
- Otitis media is a middle ear infection, common in children, that occurs when the Eustachian tube becomes blocked and the fluid that builds up in the middle ear becomes infected. (See more under Ear Problems – Middle Ear Infections)
- Otoacoustic emission (OAE) is the inaudible, but measurable, sounds created by the vibrations of hair cells in the cochlea, which bend with the movement of fluid.
- Otolaryngologist is an ENT physician trained to diagnose diseases of the ear, sinuses, mouth, throat, larynx, and other structures of the head and neck. (See more under Hearing Specialists.)
- Otologist is an otolaryngologist who has completed a specialty fellowship focusing on ear disorders. (See more under Hearing Specialists.)
- Otosclerosis is a condition in which a growth of spongy bone forms around the oval window and stirrup, causing the stirrup to become immobile, resulting in conductive hearing loss.
- Ototoxic indicates that something is harmful to hearing, as in ototoxic medications that aggravate existing hearing problems or cause new ones.
- Posturography is a test that measures how balance is maintained in an individual when one or more senses are blocked.
- Presbycusis is the hearing loss associated with aging that develops when hair cells within the cochlea wear out, causing a loss of sensitivity to sound.
- Rotation test is one that monitors the eye movements in relation to body rotation.
- Saccule is the chamber in the vestibular labyrinth that helps monitor the position of the head in relation to the ground; responsible for detection of vertical movement.
- Semicircular canal refers to any of the three tubes that form the vestibular labyrinth in the inner ear. The canals are filled with fluid and contain hair cells sensitive to fluid movement, which assist with the sense of balance.
- Sensorineural hearing loss results from damage to the inner ear, auditory nerve, or the brain.
- Speech reception threshold is the faintest level at which an individual can understand speech at least half the time.
- Stapedotomy is the surgical removal of the stirrup and performed to treat otosclerosis. The immobile stirrup is replaced with a prosthesis.
- Sudden sensorineural hearing loss occurs in the inner ear all at once or within only a few days.
- Telecommunications device for the deaf (TDD) is a text telephone that allows people with very limited or no hearing to communicate over the phone.
- Tinnitus is the sensation of ringing or buzzing in the ears that comes from no apparent source in the immediate surroundings.
- Tympanic membrane (eardrum) is a thin, taut membrane that covers the entrance to the middle ear.
- Tympanometry is a test that checks the function of the eardrum and middle ear by measuring whether the eardrum moves normally when varying amounts of air pressure are applied to the ear.
- Utricle is the chamber in the vestibular labyrinth that helps monitor the position of the head in relation to the ground. The utricle is responsible for detection of horizontal movement.
- Ventilation tube is a small tube inserted into the eardrum that relieves the pressure of a middle ear infection by allowing fluid to drain from the middle ear.
- Vertigo is the intense feeling that you or your surroundings are spinning or whirling. It is often associated with a problem in the system of balance, which is regulated by the inner ear. (See more under Balance Problems.)
- Vestibular labyrinth is the structure of the inner ear made up of three fluid-filled, semicircular tubes that assist with balance.
- Vestibular rehabilitation is a therapeutic program that uses exercise to help regain the sense of balance.
- Word recognition testing determines how well single-syllable words are heard.
