Hearing impairment


Deafness is the inability for the ear to interpret certain or all frequencies of sound.

Environmental Situations

Deafness can be caused by environmental situations such as noise, trauma, or other ear defections. Dangerous Decibels, a group that is attempting to help reduce deafness, states that anything over 85 decibels, which is about the level of a busy city, will damage hearing. Listening to loud noises for long periods of time make the eardrum less sensitive, which in turn makes it difficult to pick up quiet sounds more difficult to hear. Going through a trauma, like a car accident, can cause hearing loss due to the noise of the incident or an injury to the ear. If the middle ear
Middle ear
The middle ear is the portion of the ear internal to the eardrum, and external to the oval window of the cochlea. The mammalian middle ear contains three ossicles, which couple vibration of the eardrum into waves in the fluid and membranes of the inner ear. The hollow space of the middle ear has...

 or inner ear
Inner ear
The inner ear is the innermost part of the vertebrate ear. In mammals, it consists of the bony labyrinth, a hollow cavity in the temporal bone of the skull with a system of passages comprising two main functional parts:...

 is damaged during the accident then hearing will degenerate because the sound wave cannot make it to the brain to be interpreted into sound. Other environmental factors that can cause deafness are nasal allergies. Nasal allergies cause mucus to build up in the throat and the nose, which will block the eustachain tubes and make it difficult for sound waves to make it into the inner ear.


Diseases such as Meniere’s, meningitis, and mumps can affect hearing. Meniere’s disease is a virus that makes it so the inner ear fluid is unable to drain. This excess fluid increases pressure of the ear and makes it difficult for sound waves to travel to the brain. Because Meniere’s is a virus there is no cure at present. However, Meniere’s requires a trigger such as genetic predisposition or a traumatic event that changes the inner ear fluid. Meningitis
Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs...

 is the inflammation of protective membranes around the brain or the spine. This prevents the auditory nerve from transmitting signals to the brain. Meningitis is usually the result of an infection that went untreated and spread to the brain. Mumps
Mumps is a viral disease of the human species, caused by the mumps virus. Before the development of vaccination and the introduction of a vaccine, it was a common childhood disease worldwide...

 is a viral that usually infects the parotid salivary gland. A serious side effect of mumps is hearing loss due to the swelling of the parotid gland which blocks the sound waves from reaching the middle ear. There are many diseases that affect hearing but Meniere’s and meningitis are the leaders with 3-5 million people suffering at present and more than 10,000 being diagnosed annually. Mumps are not as common is the states but is more common around the world but is still relatively rare. On average there are only 14 deaths around the world annually.

Neurological Disorders

Neurological disorders such as multiple sclerosis
Multiple sclerosis
Multiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms...

 and strokes can have an effect on hearing as well. Multiple sclerosis, or MS, is an autoimmune disease
Autoimmune disease
Autoimmune diseases arise from an overactive immune response of the body against substances and tissues normally present in the body. In other words, the body actually attacks its own cells. The immune system mistakes some part of the body as a pathogen and attacks it. This may be restricted to...

 where the immune system attacks the myelin sheath, a covering that protects the nerves. Once the myelin sheaths are destroyed there is no possible way at present to repair them. Without the myelin to protect the nerves, nerves become damaged creating disorientation for the patient. This is a painful process and may end in the debilitation of the infected person until they are paralyzed and have one or more sense gone. One of those may be hearing. If the auditory nerve becomes damaged then the infected person will become completely deaf in one or both ears. There is no cure to MS. A stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...

 occurs if there is a clot in the brain, and blood is unable to get to a section of the brain. Within minutes the oxygen deprived cells will begin to die causing serious damage to the human body. Depending on what nerves are damaged, one of the side effects can be deafness.

Types of Deafness

Conductive hearing loss
Conductive hearing loss
Conductive hearing loss occurs when there is a problem conducting sound waves anywhere along the route through the outer ear, tympanic membrane , or middle ear ....

is when sound waves do not make it to the inner ear as well as it should. This could be due to a blockage in the ear canal, such as ear wax or some other sort of material, a puncture or some sort of damage in the eardrum that does not allow it to transmit the sound waves to the bones of the ear, or the bones of the ear may not vibrate as much as they need to. However, conductive hearing loss is typically only partial deafness and rarely results in complete deafness, and this type of deafness is most likely to respond to surgery or a similar type of treatment.
Sensorineural hearing loss
Sensorineural hearing loss
Sensorineural hearing loss is a type of hearing loss in which the root cause lies in the vestibulocochlear nerve , the inner ear, or central processing centers of the brain....

is caused by problems in the inner ear or in the auditory nerve. This is when the cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....

 or semicircular canal does not connect the sound wave correctly to the auditory nerve, or when the nerve itself is unable to transmit the electric impulses of the sound to the brain correctly. This type of deafness usually results in total hearing loss in one or both ears. There are many causes to this disability, but surgery has been known to fix sensorineural deafness.
Mixed hearing loss is a combination of conductive and sensorineural hearing loss. This is a combination of many problems in all parts of the ear. This typically results in complete deafness but surgeries can help treat this type of hearing loss somewhat.
Another type of hearing loss is auditory neuropathy spectrum disorder
Auditory Neuropathy Spectrum Disorder
Auditory Neuropathy Spectrum Disorder is a specific form of hearing loss defined by the presence of normal or near-normal Otoacoustic Emissions but the absence of normal Middle Ear Reflexes and severely abnormal or completely absent auditory brainstem response .Individuals presenting with this...

. People who suffer from ANSD have normal outer ear functions but have some kind of damage to the inner ear that disorganizes the sound wave so the brain is unable to interpret the information. The Teagle foundation, a collation of doctors that perform different studies, had very high results for treating ANSD with cochlear implantations. Gone untreated ANSD will cause complete deafness in both ears.


The most common hearing loss treatment is a type surgical procedure that will remove a blockage in the outer ear. This is almost always effective and will treat conductive hearing loss however surgery is only possible if the cause of the hearing loss can be identified. If not a hearing can be used to amplify sound to make it clearer and more defined. The newest treatment for ANSD and sensorineural hearing loss is a cochlear implant. The cochlear implant is surgically installed to connect to the auditory nerve. The implant has a membrane that vibrates when sound hits it and sends signals to the nerve which then transmits the stimulus to the brain. The cochlear implant has only one membrane compared to the human ear’s three membranes. This means that sound will not be as clear using the cochlear when juxtaposed to normal hearing, but sounds can still be identified and responses can be made.
This is a great scientific innovation that allows the deaf to hear. It may not be as perfect as our normal hearing but doctors agree that it is the best treatment.

Deaf Culture

Jack Gannon, a professor at Gallaudet University said this about deaf culture
Deaf culture
Deaf culture describes the social beliefs, behaviors, art, literary traditions, history, values and shared institutions of communities that are affected by deafness and which use sign languages as the main means of communication. When used as a cultural label, the word deaf is often written with a...

. “Deaf culture is a set of learned behaviors and perceptions that shape the values and norms of deaf people based on their shared or common experiences.” Some doctors believe that being deaf makes a person more social. Dr. Bill Vicar, from ASL University, shared his experiences as a deaf person, “[deaf people] tend to congregate around the kitchen table rather than the living room sofa… our good-byes take nearly forever, and our hellos often consist of serious hugs. When two of us meet for the first time we tend to exchange detailed biographies.” Deaf culture is not about contemplating what deaf people cannot do and how to fix their problems. This is what they call a pathological view of the deaf. Instead deaf people celebrate what they can do. There is a strong sense of unity between deaf people as they share their experiences of suffering through a similar struggle. This celebration creates a unity between even deaf strangers. Dr. Bill Vicars expresses the power of this bond when stating, “if given the chance to become hearing most [deaf people] would choose to remain deaf.” There is more to deaf culture than meets the eye and has to be “experienced” to full comprehend it.


Abbe Charles Michel de l’Epee was the first person to open a deaf school. L’Epee taught French sign language to children, and started the spread of many deaf schools across Europe. Thomas Gallaudet was traveling to England to start a deaf school. His inspiration was a nine-year old girl who lived next door. Seeing her conquer her struggles made Gallaudet want to teach and see other children conquer their own disabilities. Gallaudet witnessed a demonstration of deaf teaching skills from Sicard, Massieu, and Clerc, the masters of teaching deaf children at the time. After the demonstration of Gallaudet studied under the French masters and perfected his own teaching skills. Once he was done learning Gallaudet and Clerc traveled to the United States and opened the first deaf school in Hartford Connecticut. American Sign Language
American Sign Language
American Sign Language, or ASL, for a time also called Ameslan, is the dominant sign language of Deaf Americans, including deaf communities in the United States, in the English-speaking parts of Canada, and in some regions of Mexico...

, or ASL, started to evolve from primarily LSf, French sign language, and other outside influences.

ASL in the present

American Sign Language consists of different hand signals to mean different words. ASL also has signs for the alphabet which is primarily used to spell names. ASL also uses: facial expressions, body language, hand shape, hand position, hand movement, and gestures, all of these things affect the meaning or sincerity of the signs that are used. ASL is offered at most major schools and is recognized as its own language. There are ASL translator’s at most major events and special seating to accommodate any deaf members of the audience. ASL is what makes deaf culture possible. Deaf people can communicate in their own way and do not have to rely on reading lips or technology to help them. ASL is an amazing invention that has defined a people and has created a new culture.

Historical Deaf People

Helen Keller
Helen Keller
Helen Adams Keller was an American author, political activist, and lecturer. She was the first deafblind person to earn a Bachelor of Arts degree....

- American author and activist
Thomas Edison
Thomas Edison
Thomas Alva Edison was an American inventor and businessman. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb. In addition, he created the world’s first industrial...

- inventor
Ludwig Van Beethoven
Ludwig van Beethoven
Ludwig van Beethoven was a German composer and pianist. A crucial figure in the transition between the Classical and Romantic eras in Western art music, he remains one of the most famous and influential composers of all time.Born in Bonn, then the capital of the Electorate of Cologne and part of...

- Classical Composer
Trix Bruce- Actor
Pete Townshend
Pete Townshend
Peter Dennis Blandford "Pete" Townshend is an English rock guitarist, vocalist, songwriter and author, known principally as the guitarist and songwriter for the rock group The Who, as well as for his own solo career...

- Musician
Johnnie Ray
Johnnie Ray
Johnnie Ray was an American singer, songwriter, and pianist. Popular for most of the 1950s, Ray has been cited by critics as a major precursor of what would become rock and roll, for his jazz and blues-influenced music and his animated stage personality.-Early life:John Alvin Ray was born in...

- Singer
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