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November 22, 2009
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 Deafness Main Article |  Glossary |  Deafness Index 

Deafness, Hearing Loss Glossary of Terms

The following are health and medical definitions of terms that appear in the Deafness, Hearing Loss article.

Acquired: Anything that is not present at birth but develops some time later. In medicine, the word "acquired" implies "new" or "added." An acquired condition is "new" in the sense that it is not genetic (inherited) and "added" in the sense that was not present at birth.
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Acquired deafness : The loss of hearing that occurs or develops some time during a person's life but was not present at birth.
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Aging: The process of becoming older, a process that is genetically determined and environmentally modulated.
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Aspirin: A good example of a tradename that entered into the language, Aspirin was once the Bayer trademark for acetylsalicylic acid .
See the entire definition of Aspirin

Brain: That part of the central nervous system that is located within the cranium ( skull ). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres."
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Cochlea: The cochlea is the part of the inner ear that converts mechanical energy (vibrations) into nerve impulses sent to the brain. It is also known as the organ of hearing.
See the entire definition of Cochlea

Condition: The term "condition" has a number of biomedical meanings including the following:

  1. An unhealthy state, such as in "this is a progressive condition."
  2. A state of fitness, such as "getting into condition."
  3. Something that is essential to the occurrence of something else; essentially a "precondition."
  4. As a verb: to cause a change in something so that a response that was previously associated with a certain stimulus becomes associated with another stimulus; to condition a person, as in behavioral conditioning.

Congenital: Present at birth. A condition that is congenital is one that is present at birth. There are numerous uses of "congenital" in medicine. There are, for example, congenital abnormalities. (For more examples, see below.)
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Congenital deafness : Loss of hearing present at birth.
See the entire definition of Congenital deafness

Cranial: 1. Pertaining to the cranium or skull. 2. Toward the head. As opposed to caudad. The eye is cranial to the jaw. For a more complete listing of terms used in medicine for spatial orientation, please see the entry to "Anatomic Orientation Terms".

Deafness: Deafness is defined by partial or complete hearing loss. Levels of hearing impairment vary from a mild but important loss of sensitivity to a total loss of hearing. Older adults suffer most often from hearing loss. Age-related hearing loss affects 30 to 35 percent of the population between the ages of 65 and 75 years, and 40 percent of the population over the age of 75. The most common cause of hearing loss in children is otitis media, a disorder that affects predominantly infants and young children. A substantial number of hearing impairments are caused by environmental factors such as noise, drugs, and toxins. Many sensorineural hearing losses result from a genetic predisposition.

Disease: Illness or sickness often characterized by typical patient problems (symptoms) and physical findings (signs). Disruption sequence: The events that occur when a fetus that is developing normally is subjected to a destructive agent such as the rubella (German measles) virus.

Ear: The hearing organ. There are three sections of the ear, according to the anatomy textbooks. They are the outer ear (the part we see along the sides of our head behind the temples), the middle ear, and the inner ear. But in terms of function, the ear has four parts: those three and the brain. Hearing thus involves all parts of the ear as well as the auditory cortex of the brain. The external ear helps concentrate the vibrations of air on the ear drum and make it vibrate. These vibrations are transmitted by a chain of little bones in the middle ear to the inner ear. There they stimulate the fibers of the auditory nerve to transmit impulses to the brain.
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Ear wax : A natural wax-like substance secreted by special glands in the skin on the outer part of the ear canal. It repels water, and traps dust and sand particles. Usually a small amount of wax accumulates, and then dries up and falls out of the ear canal carrying with it unwanted particles. Ear wax is helpful in normal amounts and serves to coat the skin of the ear canal where it acts as a temporary water repellent. The absence of ear wax may result in dry, itchy ears, and even infection.
See the entire definition of Ear wax

Eardrum: The tympanic membrane of the ear, or tympanum, the membrane that separates the middle ear from the external ear.

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Eighth cranial nerve: The eighth cranial nerve is the vestibulocochlear nerve.
See the entire definition of Eighth cranial nerve

Genetic: Having to do with genes and genetic information.

Genetic disease: A disease caused by an abnormality in an individual's genome .
See the entire definition of Genetic disease

Idiopathic: Of unknown cause. Any disease that is of uncertain or unknown origin may be termed idiopathic. For example, acute idiopathic polyneuritis , diffuse idiopathic skeletal hyperostosis , idiopathic pulmonary fibrosis , idiopathic scoliosis , etc.
See the entire definition of Idiopathic

Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person.
See the entire definition of Infection

Injury: Harm or hurt. The term "injury" may be applied in medicine to damage inflicted upon oneself as in a hamstring injury or by an external agent on as in a cold injury. The injury may be accidental or deliberate, as with a needlestick injury. The term "injury" may be synonymous (depending on the context) with a wound or with trauma.

Membrane: A very thin layer of tissue that covers a surface.

Mother: (1) The female parent. (2) To produce offspring as a female. To attribute the maternity of. (3) A cell or other structure from which similar cells or structures are formed. Accordingly, such a cell might be referred to as the mother cell.(4) To provide maternal protection, guidance, and nurturing to children.
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Nerve: A bundle of fibers that uses chemical and electrical signals to transmit sensory and motor information from one body part to another. See: Nervous system.

Otitis: Inflammation of the ear. Depending upon which part of the ear is inflammed, there is otitis externa, otitis media, and otitis interna.

Otitis media : Inflammation of the middle ear characterized by the accumulation of fluid in the middle ear, bulging of the eardrum, pain in the ear and, if eardrum is perforated, drainage of purulent material (pus) into the ear canal.
See the entire definition of Otitis media

Otosclerosis: The abnormal formation of new bone in the middle ear that gradually immobilizes the stapes (stirrup bone) and prevents it from vibrating in response to sound, causing progressive loss of hearing. Otosclerosis usually affects both ears. It is a common disorder, especially among young women. Pregnancy may trigger it.

Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long.
See the entire definition of Pregnancy

Presbycusis: Age-related hearing loss with gradually progressive inability to hear, especially high frequency sounds. Presbycusis most often occurs in both ears. Because the loss of hearing is so gradual, people with presbycusis may not realize that their hearing is diminishing. They may have trouble distinguishing and understanding conversation in a noisy setting. Environmental exposures (such as to guns, power tools, industrial machinery, or very loud music) contribute significantly to presbycusis, but up to half of presbycusis is genetically determined. Presbycusis is common, affecting a third of people between 65 and 75 years and up to a half of people 75 and over. The hearing loss can usually be corrected with a hearing aid.

Spinal cord: The major column of nerve tissue that is connected to the brain and lies within the vertebral canal and from which the spinal nerves emerge. Thirty-one pairs of spinal nerves originate in the spinal cord: 8 cervical , 12 thoracic , 5 lumbar, 5 sacral, and 1 coccygeal. The spinal cord and the brain constitute the central nervous system ( CNS ). The spinal cord consists of nerve fibers that transmit impulses to and from the brain. Like the brain, the spinal cord is covered by three connective-tissue envelopes called the meninges . The space between the outer and middle envelopes is filled with cerebrospinal fluid ( CSF ), a clear colorless fluid that cushions the spinal cord against jarring shock. Also known simply as the cord.
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Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease.
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Syphilis: A sexually transmitted disease caused by Treponema pallidum, a microscopic organism called a spirochete. This worm-like, spiral-shaped organism infects people by burrowing into the moist mucous membranes of the mouth or genitals. From there, the spirochete produces a non-painful ulcer known as a chancre. There are three stages of syphilis:
See the entire definition of Syphilis

Toxicity: The degree to which a substance can harm humans or animals.
See the entire definition of Toxicity

Tympanic: 1. Pertaining to the tympanum (the eardrum).
2. Pertaining to the tympanic cavity.
3. Bell-like or resonant.

Tympanic membrane: Just the ear drum.

Virus: A microorganism smaller than a bacteria, which cannot grow or reproduce apart from a living cell. A virus invades living cells and uses their chemical machinery to keep itself alive and to replicate itself. It may reproduce with fidelity or with errors (mutations)-this ability to mutate is responsible for the ability of some viruses to change slightly in each infected person, making treatment more difficult.
See the entire definition of Virus

Waardenburg syndrome: A genetic disorder that causes deafness , white forelock (a frontal white blaze of hair), a difference of color between the iris of one eye and the other (heterochromia iridis), white eye lashes, and wide-set inner corners of the eyes.
See the entire definition of Waardenburg syndrome back to top

 Deafness Main Article |  Glossary |  Deafness Index 




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Deafness, Hearing Loss

What is otitis media?

Otitis media is inflammation of the middle ear. "Otitis" means inflammation of the ear, and "media" means middle. This inflammation often begins with infections that cause sore throats, colds or other respiratory problems, and spreads to the middle ear. These can be caused by viruses or bacteria, and can be acute or chronic.

Acute otitis media is usually of rapid onset and short duration. Acute otitis media is typically associated with fluid accumulation in the middle ear together with signs or symptoms of ear infection; a bulging eardrum usually accompanied by pain, or a perforated eardrum, often with drainage of purulent material (pus). Fever can be present.

Chronic otitis media is a persistent inflammation of the middle ear, typically for a minimum of a month. This is in distinction to an acute ear infection (acute otitis media) that usually lasts only several weeks. Following an acute infect...

Read the Otitis Media article »










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