| A | B | C | D | E | F | G | H | I | L

| M | N | O | P | R | S | T | U | V | W |


A [return to top]

acoustic neurinoma - a tumor, usually benign, which develops on the hearing and balance nerves and can cause gradual hearing loss, tinnitus, and dizziness.

acquired deafness - loss of hearing that occurs or develops over the course of a lifetime; deafness not present at birth.

adrenaline - see epinephrine.

aguesia - loss of the sense of taste.

allergen - the substance that triggers an allergic reaction.

allergy - an acquired, abnormal immune response to a substance that can cause a broad range of inflammatory reactions.

Alport’s syndrome - A hereditary condition characterized by kidney disease, sensorineural hearing loss, and some difficulties with eye defects.

American Sign Language (ASL) - Manual (hand) language with its own syntax and grammar used primarily by people who are deaf.

anaphylaxis (anaphylactic shock) - a sudden, severe, potentially life-threatening allergic reaction caused by food allergy, insect stings or medications. Symptoms can include hives, swelling (especially of the lips and face), difficulty breathing (either because of swelling in the throat or an asthmatic reaction), vomiting, diarrhea, cramping and a fall in blood pressure.

anosmia - absence of the sense of smell.

antibody (also called an immunoglobulin) - a complex protein that is manufactured by lymphocytes to neutralize or destroy an antigen or foreign protein. Many types of antibodies are protective, however, inappropriate or excessive formation of antibodies may lead to illness.

antigen - a substance that can trigger an immune response causing the production of antibodies as part of the body's defense against infection and disease.

antihistamine drugs - a group of drugs that block the effects of histamine, a chemical released in body fluids during an allergic reaction.

anti-inflammatory drugs - drugs that reduce the symptoms and signs of inflammation.

aphasia - total or partial loss of ability to use or understand language; usually caused by stroke, brain disease, or injury.

aphonia - complete loss of voice.

apraxia - inability to make a voluntary movement in spite of being able to demonstrate normal muscle function.

articulation disorder - inability to correctly produce speech sounds (phonemes) because of imprecise placement, timing, pressure, speed, or flow of movement of the lips, tongue, or throat.

assistive devices - technical tools and devices such as alphabet boards, text telephones, or text-to-speech conversion software used to assist people with physical or emotional disorders in performing certain actions, tasks, and activities.

asthma - a chronic, inflammatory lung disease characterized by recurrent breathing problems usually triggered by allergens (infection, exercise, cold air, and other factors may also be triggers).

audiologist - a healthcare professional trained to identify and measure hearing impairments and related disorders using a variety of tests and procedures.

auditory brainstem response (ABR) test - test used for hearing in infants and young children, or to test for brain functioning in unresponsive patients.

auditory nerve - eighth cranial nerve that connects the inner ear to the brainstem.

auditory perception- ability to identify, interpret, and attach meaning to sound.

auditory prosthesis - device that substitutes or enhances the ability to hear.

augmentative devices - tools that help individuals with limited or absent speech to communicate.

aural rehabilitation - techniques used with people who are hearing impaired to improve ability to speak and to communicate.

autoimmune deafness - hearing loss in an individual that may be associated with a tissue-causing disease, such as rheumatoid arthritis or lupus.

autism - brain disorder that begins in early childhood and persists throughout adulthood; affects three crucial areas of development: communication, social interaction, and creative or imaginative play.

B [return to top]

balance - biological system that enables individuals to know where their bodies are in the environment and to maintain a desired position; normal balance depends on information from the labyrinth in the inner ear, and from other senses such as sight and touch, as well as from muscle movement.

balance disorder - disruption in the labyrinth, the inner ear organ that controls the balance system allowing individuals to know where their bodies are in the environment.

barotrauma - injury to the middle ear caused by a reduction of air pressure.

benign paroxysmal positional vertigo (BPPV) - balance disorder that results in a sudden onset of dizziness, spinning, or vertigo that occurs when suddenly moving the head from one position to another.

brainstem implant - auditory prosthesis that bypasses the cochlea and auditory nerve to help individuals who cannot benefit from a cochlear implant because the auditory nerves are not working.

bronchitis - an inflammation of the mucous membranes of the bronchial tubes, causing a persistent cough that produces considerable quantities of sputum (phlegm).

bronchodilators - a group of drugs that widen the airways in the lungs.

bronchus - any of the larger air passages that connect the trachea to the lungs.

C [return to top]

captioning - text display of spoken words presented on a television or a movie screen that allows a deaf or hard-of-hearing viewer to follow the dialogue and the action of a program simultaneously.

celiac disease (also called celiac sprue or gluten sensitive enteropathy) - a sensitivity to gluten, a wheat protein. Individuals with this disease must avoid gluten-containing grains, which include all forms of wheat, oats, barley, and rye.

central auditory processing disorder - inability of individuals with normal hearing and intelligence to differentiate, recognize, or understand sounds.

chemosensory disorders - disorders or diseases of smell or taste.

cholesteatoma - accumulation of dead cells in the middle ear caused by repeated middle ear infections.

cochlea - snail-shaped structure in the inner ear that contains the organ of hearing.

cochlear implant - medical device that bypasses damaged structures in the inner ear and directly stimulates auditory nerve to allow some deaf individuals to learn to hear and interpret sounds and speech.

conductive hearing impairment - hearing loss caused by dysfunction of the outer or middle ear.

contact dermatitis - a rash or an inflammation of the skin caused by contact with various substances.

corticosteroids - a group of anti-inflammatory drugs similar to the natural corticosteroid hormones produced by the adrenal glands.

cued speech - method of communication that combines speech reading with a system of handshapes placed near the mouth to help deaf or hard-of-hearing individuals differentiate words that look similar on the lips.

cytomegalovirus (congenital) - one group of herpes viruses that infect humans and can cause a variety of clinical symptoms including deafness or hearing impairment; infection with the virus may be either before or after birth.

D [return to top]

decibel - unit that measures the intensity or loudness of sound.

digestive system - the group of organs that break down foods into chemical components that the body can absorb and use for energy, and for building and repairing cells and tissues.

dizziness - physical unsteadiness, imbalance, and lightheadedness associated with balance disorders.

dysarthia - group of speech disorders caused by disturbances in the strength or coordination of the muscles of the speech mechanism as a result of damage to the brain or nerves.

dysequilibrium - any disturbance of balance.

dysfluency - disruption in the smooth flow or expression of speech.

dysgeusia - distortion or absence of the sense of taste.

dysosmia - distortion or absence of the sense of smell.

dysphagia - difficulty swallowing.

dysphonia - any impairment of the voice or difficulty speaking.

dyspraxia of speech - partial loss of the ability to consistently pronounce words in individuals with normal muscle tone and coordination of the speech muscles.

dystonia - abnormal muscle tone of one or more muscles.

E [return to top]

ear infection - presence and growth of bacteria or viruses in the ear.

ear wax - yellow secretion from glands in the outer ear (cerumen) that keeps the skin of the ear dry and protected from infection.

eczema - inflammation of the skin, usually causing itching and sometimes accompanied by crusting, scaling, or blisters.

endolymph - fluid in the labyrinth -- the organ of balance located in the inner ear.

epinephrine - one of two chemicals (the other is norepinephrine) released by the adrenal gland that increases the speed and force of heart beats. It dilates the airways to improve breathing and narrows blood vessels in the skin and intestine so that an increased flow of blood reaches the muscles and allows them to cope with the demands of exercise.

extrinsic asthma - asthma that is triggered by an allergic reaction, usually to something that is inhaled.

F [return to top]

food intolerance - an adverse food-induced reaction that does not involve the immune system. Lactose intolerance is an example.

G [return to top]

gluten sensitive enteropathy (also called celiac sprue or celiac disease) - a sensitivity to gluten, a wheat protein. Individuals with this disease must avoid gluten-containing grains, which include all forms of wheat, oats, barley and rye.

gustation - act or sensation of tasting.

H [return to top]

hair cells - sensory cells of the inner ear, which are topped with hair-like structures (stereocilia), which transform the mechanical energy of sound waves into nerve impulses.

hay fever - see rhinitis.

hearing - series of events in which sound waves in the air are converted to electrical signals that are sent as nerve impulses to the brain where they are interpreted.

hearing aid - electronic device that brings amplified sound to the ear.

hearing disorder - disruption in the normal hearing process; sound waves are not converted to electrical signals and nerve impulses are not transmitted to the brain to be interpreted.

histamine - a chemical present in cells throughout the body that is released during an allergic reaction and one of the substances responsible for the symptoms of inflammation.

hives - see urticaria.

hoarseness - abnormally rough or harsh-sounding voice caused by vocal abuse and other disorders.

hypogeusia - diminished sensitivity to taste.

hyposmia - diminished sensitivity to smell.

I [return to top]

inner ear - part of the ear that contains both the organ of hearing (the cochlea) and the organ of balance (the labyrinth).

immune system - a collection of cells and proteins that works to protect the body from potentially harmful, infectious microorganisms, such as bacteria, viruses, and fungi.

immunoglobulin E (IgE) - a type of antibody, formed to protect the body from infection, which attaches to mast cells in the respiratory and intestinal tracts and may cause allergic rhinitis, asthma, or eczema.

immunoglobulins - antibodies or proteins found in blood and tissue fluids produced by cells of the immune system to bind to substances in the body that are recognized as foreign antigens. Immunoglobulins sometimes bind to antigens that are not necessarily a threat to health and provoke an allergic reaction.

immunotherapy - treatment of allergy to substances such as pollens, house dust mites, fungi, and stinging insect venom involving giving gradually increasing doses of the substance, or allergen, to which the person is allergic.

inflammation - redness, swelling, heat, and pain in a tissue due to chemical or physical injury, infection, or allergic reactions in the nose, lungs, and skin.

intrinsic asthma -asthma that has no apparent external cause.

L [return to top]

labyrinth - organ of balance located in the inner ear. The labyrinth consists of three semicircular canals and the vestibule.

labyrinthine hydrops - excessive fluid in the organ of balance (labyrinth) that can cause pressure or fullness in the ears, hearing loss, dizziness, and loss of balance.

labyrinthitis - viral or bacterial infection or inflammation of the inner ear that can cause dizziness, loss of balance, and temporary hearing loss.

lactose intolerance - a food intolerance not allergy. A person with lactose intolerance lacks an enzyme that is needed to digest milk sugar, which causes symptoms such as gas, bloating, and abdominal pain.

Landau-Kleffner syndrome - A childhood disorder of unknown origin that can be identified by gradual or sudden loss of the ability to understand and use spoken language.

language - system for communicating ideas and feelings using sounds, gestures, signs, or marks.

language disorders - problems with verbal communication and the ability to use or understand the symbol system for interpersonal communication.

laryngeal neoplasms - abnormal growths in the larynx (voice box) that can be cancerous or noncancerous.

laryngeal nodules - noncancerous, callous-like growths on the inner parts of the vocal folds (vocal cords).

laryngeal paralysis - loss of function or feeling of one or both of the vocal folds.

laryngectomy - surgery to remove part or all of the larynx or voice box.

laryngitis - hoarse voice or the complete loss of the voice because of irritation to the vocal folds (vocal cords).

larynx - valve structure between the trachea (windpipe) and the pharynx (the upper throat) that is the primary organ of voice production.

lymphocyte - any one of a group of white blood cells of crucial importance to the adaptive part of the body's immune system.

M [return to top]

mast cells - cells, which synthesize and store histamines, found in most body tissues, particularly just below the epithelial surfaces, serous cavities and around blood vessels. In an allergic response, an allergen stimulates the release of antibodies, which attach themselves to mast cells.

mastoid - back portion of the temporal bone behind the ear.

mastoid surgery - surgical procedure to remove infection from the mastoid bone.

Meige syndrome - A movement disorder that can involve excessive eye blinking (blepharospasm) with involuntary movements of the jaw muscles, lips, and tongue (oromandibular dystonia).

Meniere’s disease - An inner ear disorder that can affect both hearing and balance; can cause vertigo, hearing loss, tinnitus, and the sensation of fullness in the ear.

meningitis - inflammation of the meninges, the membranes that envelop the brain and the spinal cord; may cause hearing loss or deafness.

middle ear - part of the ear that includes the eardrum and three tiny bones of the middle ear, ending at the round window that leads to the inner ear.

misarticulation - inaccurately produced speech sound (phoneme) or sounds.

motion sickness - dizziness, sweating, nausea, vomiting, and generalized discomfort experienced when an individual is in motion.

motor speech disorders - group of disorders caused by the inability to accurately produce speech sounds (phonemes).

N [return to top]

neural plasticity - ability of the brain and/or certain parts of the nervous system to change in order to adapt to new conditions, such as an injury.

neural prostheses - devices that substitute for an injured or diseased part of the nervous system to enhance the function.

neural stimulation - to activate or energize a nerve through an external source.

neurofibromatosis (Von Recklinghausen’s) - a group of inherited disorders in which noncancerous tumors grow on several nerves that may include the hearing nerve.

neurogenic communication disorder - inability to exchange information with others because of hearing, speech, and/or language problems caused by impairment of the nervous system.

noise-induced hearing loss - hearing loss that is caused either by a one-time or repeated exposure to very loud sound(s) or sounds at various loudness levels over an extended period of time.

nonsyndromic hereditary hearing impairment - hearing loss or deafness that is inherited and is not associated with other inherited clinical characteristics.

O [return to top]

odorant - substance that stimulates the sense of smell.

olfaction - the act of smelling.

olfactometer - device for estimating the intensity of the sense of smell.

open-set speech recognition - understanding speech without visual clues.

otitis media - inflammation of the middle ear caused by infection.

otitis externa - inflammation of the outer part of the ear extending to the auditory canal.

otoacoustic emissions - low-intensity sounds produced by the inner ear that can be quickly measured with a sensitive microphone placed in the ear canal.

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 - abnormal growth of bone in the inner ear, which prevents structures within the ear from working properly, resulting in a gradual loss of hearing.

ototoxic drugs - drugs that can damage the hearing and balance organs located in the inner ear.

outer ear - external portion of the ear, consisting of the pinna, or auricle, and the ear canal.

P [return to top]

parosmia - any disease or perversion of the sense of smell, especially the subjective perception of odors that do not exist.

peak flow meter - a portable, inexpensive, hand-held device used to measure how air flows from lungs in one "fast blast" to measure the ability to push air out of the lungs. Measurements with a peak flow meter help the patient and physician monitor your asthma. These measurements can be important and help your physician prescribe medicines to keep asthma in control.

perception (hearing) - process of knowing or being aware of information through the ear.

perilymph fistula - leakage of inner ear fluid to the middle ear that occurs without apparent cause or is associated with head trauma, physical exertion, or barotrauma.

phonology - study of speech sounds.

postlingually deafened - individual who becomes deaf after having learned language.

prelingually deafened - individual who is either born deaf or who lost hearing early in childhood, before learning language.

presbycusis - loss of hearing that gradually occurs because of changes in the inner or middle ear in individuals as they grow older.

prick skin test - a test to determine if a patient is allergic to certain substances. A physician places a drop of the substance being tested on the patient's forearm or back and pricks the skin with a needle, allowing a tiny amount to enter the skin. If the patient is allergic to the substance, a wheal (mosquito bite-like bump) will form at the site within about 15 minutes.

R [return to top]

RAST - (RadioAllergoSorbent Test, a trademark of Pharmacia Diagnostics) - a laboratory test used to detect IgE antibodies to specific allergens. A RAST requires a blood sample, which is sent to a medical laboratory where tests are done with specific foods to determine whether the patient has IgE antibodies to that food.

respiratory system - the group of organs responsible for carrying oxygen from the air to the bloodstream and for expelling carbon dioxide.

rhinitis - an inflammation of the mucous membrane that lines the nose, often due to allergy to pollen, dust or other airborne substances, which causes sneezing, itching, a runny nose and nasal congestion.

round window - membrane separating the middle ear and inner ear.

S [return to top]

sensorineural hearing loss - hearing loss caused by damage to the sensory cells and/or nerve fibers of the inner ear.

sign language - language of hand shapes, facial expressions, and movements used as a form of communication.

sinus (paranasal sinuses) - air cavities within the facial bones, lined by mucous membranes similar to those in other parts of the airways.

sinusitis - inflammation of the membranes lining the facial sinuses, often caused by bacterial or viral infection, or allergic reaction.

smell - to perceive odor or scent through stimuli affecting the olfactory nerves.

smell disorder - inability to perceive odors that may be temporary or permanent.

sound vocalization - ability to produce voice.

spasmodic dysphonia - momentary disruption of voice caused by involuntary movements of one or more muscles of the larynx or voice box.

specific language impairment (or SLI) - difficulty with the organized-symbol-system communication in the absence of problems such as mental retardation, hearing loss, or emotional disorders.

speech - making definite vocal sounds that form words to express thoughts and ideas.

speech disorder - defect or abnormality that prevents an individual from communicating by means of spoken words.

speech processor - part of a cochlear implant that converts speech sounds into electrical impulses to stimulate the auditory 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.

stuttering - frequent repetition of words or parts of words that disrupts the smooth flow of speech.

sudden deafness - loss of hearing that occurs quickly from such causes as explosion, a viral infection, or the use of some drugs.

swallowing disorders - any of a group of problems that interfere with the transfer of food from the mouth to the stomach.

syndromic hearing impairment - hearing loss or deafness that is inherited or passed through generations of a family.

T [return to top]

taste - sensation produced by a stimulus applied to the gustatory nerve endings in the tongue; the four tastes are salt, sour, sweet, and bitter; some say there is a fifth taste described as savory.

taste disorder - inability to perceive different flavors.

taste buds - groups of cells located on the tongue that enable one to recognize different tastes.

throat disorders - disorders or diseases of the larynx (voice box) or esophagus.

thyroplasty - surgical technique to improve voice by altering the cartilages of the larynx. Also known as laryngeal framework surgery.

tinnitus - sensation of a ringing, roaring, or buzzing sound in the ears or head; often associated with various forms of hearing impairment.

tongue - large muscle on the floor of the mouth that manipulates food for chewing and swallowing; the main organ of taste, and assists in forming speech sounds.

Tourette syndrome - Neurological disorder characterized by recurring movements and sounds (called tics).

tracheostomy - surgical opening into the trachea (windpipe) to help someone breathe who has an obstruction or swelling in the larynx (voice box) or upper throat.

tympanoplasty - surgical repair of the eardrum (tympanic membrane) or bones of the middle ear.

U [return to top]

urticaria - a skin condition, commonly known as hives, characterized by the development of itchy, raised white lumps surrounded by an area.

Usher’s syndrome - A hereditary disease that affects hearing and vision.

V [return to top]

velocardiofacial syndrome - inherited disorder characterized by cleft palate, heart defects, characteristic facial appearance, minor learning problems, and speech and feeding problems.

vertigo - illusion of movement; sensation that the external world is revolving around an individual (objective vertigo) or that the individual is revolving in space (subjective vertigo).

vestibular neuronitis - infection at the vestibular nerve.

vestibular system - system in the body that is responsible for maintaining the body’s orientation in space, balance, and posture; also regulates locomotion and other movements and keeps objects in visual focus as the body moves.

vestibule - bony cavity of the inner ear.

vibrotactile aids - mechanical instruments that help individuals who are deaf detect and interpret sound through the sense of touch.

vocal cords (vocal folds) - muscularized folds of mucous membrane that extend from the larynx (voice box) wall; enclosed in elastic vocal ligament and muscle that control the tension and rate of vibration of the cords as air passes through them.

vocal cord paralysis - inability of one or both vocal folds (vocal cords) to move because of damage to the brain or nerves.

vocal tremor - trembling or shaking of one or more of the muscles of the larynx resulting in an unsteady-sounding voice.

voice - sound produced by air passing out through the larynx and upper respiratory tract.

voice disorders - group of problems involving abnormal pitch, loudness, or quality of the sound produced by the larynx (voice box).

W [return to top]

Waardenburg syndrome - Hereditary deafness that is characterized by hearing impairment, a white shock of hair, and/or distinctive blue color to one or both eyes, as well as wide-set inner corners of the eyes; balance problems are also associated with some types of Waardenburg syndrome.