The human ear consists of three parts - the outer, middle, and inner ear.
consists of the visible part of the ear, also called the auricle, and the ear canal. What we call 'noises' are actually just 'sound waves', which are transmitted by the air. Sound waves are collected and guided through the ear canal to the eardrum. The eardrum is a flexible, circular membrane that vibrates when sound waves strike it.
is an air-filled space separated from the outer ear by the eardrum, or the tympanic (pronounced: tim-`pa-nik) membrane. In the middle ear are three tiny bones: malleus, incus, and stapes, often referred to as the hammer, the anvil, and the stirrup. They are collectively known as the ossicles. These form a bridge from the eardrum to the inner ear. The ossicles also vibrate in response to movements of the eardrum and in doing so, amplify and relay the sound to the inner ear via the oval window.
referred to as the cochlea (pronounced: kohk-le-a), is similar in shape to a snail shell. It contains several membranous sections filled with fluids. When the ossicles conduct sound to the oval window, the fluid begins to move, thus stimulating the minute hearing nerve cells, called hair cells, inside the cochlea. These hair cells in turn send electrical impulses via the auditory nerve to the brain where it will be interpreted as sound.
Loss is usually gradual, developing over a long period of time. At some point, the deterioration of hearing starts to interfere with conversational speech in many places. If you answer "yes" to many of the following questions, you may have hearing loss:
For most people, hearing loss happens slowly - so slowly in fact it's hard fo them to notice it deteriorate at all. Indeed, you may realise someone has sings of hearing loss before they realise themselves.
If someone in your life is resorting to turning the volume up for no apparent reason, it could be an indicator that they're struggling with some level of hearing loss.
In the same way our vision can become blurred so can our hearing. While it's rare not to hear people at all, your friend or loved one may be struggling to hear you clearly.
With increased background noise, social gatherings can be tricky for someone starting to experience hearing loss. As such, you may notice them avoiding these situation.
Listening with a hearing loss is hard work and requires concentration. For that reason, some people find they tire easily during conversations and often become stressed.
Conductive hearing loss: Conductive hearing loss occurs when sound is not conducted efficiently through the outer ear canal to the eardrum and the tiny bones, or ossicles, of the middle ear. Conductive hearing loss usually involves a reduction in sound level, or the ability to hear faint sounds. This type of hearing loss can often be medically or surgically corrected.
Examples of conditions that may cause a conductive hearing loss include:
Sensorineural Hearing Loss: Sensorineural
hearing loss occurs when there is damage to the inner ear
(cochlea) or to the nerve pathways from the inner ear
(retrocochlear) to the brain. Sensorineural hearing loss
cannot be medically or surgically corrected. It is a
permanent loss.Sensorineural hearing loss not only involves a
reduction in sound level, or ability to hear faint sounds,
but also affects speech understanding, or ability to hear
Sensorineural hearing loss can be caused by diseases, birth injury, drugs that are toxic to the auditory system, and genetic syndromes. Sensorineural hearing loss may also occur as a result of noise exposure, viruses, head trauma, aging, and tumors.
Mixed Hearing Loss: Sometimes a conductive hearing loss occurs in combination with a sensorineural hearing loss. In other words, there may be damage in the outer or middle ear and in the inner ear (cochlea) or auditory nerve. When this occurs, the hearing loss is referred to as a mixed hearing loss.
Unilateral Hearing Loss: Unilateral hearing loss (UHL) means that hearing is normal in one ear but there is hearing loss in the other ear. The hearing loss can range from mild to very severe. Approximately one out of 1000 children is born with UHL. Unilateral hearing loss can occur in both adults and children. Nearly 3% of school-aged children have UHL.Children with UHL are at higher risk for having academic, speech/language and social/emotional difficulties than their normal hearing peers. Some children with UHL experience these difficulties but others do not.
Many times we do not know the cause of hearing loss. Below are some possible causes of UHL:
Age : Advancing age is the most common cause of hearing loss.
Disease : Meningitis, Meniere's Syndrome, benign growths and tumors on the hearing nerve. Viral infections such as mumps and measles.
Drugs : Some drugs and antibiotics can cause damage to hair cells in the inner ear and the auditory nerve. Some of these drugs include, but are not limited too, quinine, aminoglycosides, diuretics and aspirin in large dosages.
Infections : Otitis media is a middle ear
infection characterized by the formation of fluid in the
middle ear. This can be caused by allergies, head colds,
inflamed tonsils and adenoids, blocked eustachian tubes, sore
throats and other viruses.
Malformation : A malformation of the ear canal can sometimes cause a hearing loss.
Noise : Noise exposure (hunting, factory/plant noise, engine noise) can cause permanent hearing loss. Perforation: Perforation of the eardrum can be caused by a change in air pressure associated with flying or scuba diving, a foreign object such as a cotton swab used to clean the ears or pressure caused by a middle ear infection.
Wax : Wax can build up in the ear canal and cause a blockage, which will stop sound from passing through the ear canal. A physician, nurse or audiologist can periodically remove the ear wax. (Cotton swabs or sharp objects should never be used to clean the ears because they can push the wax deeper into the ear and may puncture the eardrum).
Degree of hearing loss refers to the severity of the loss. The numbers are representative of the patient's thresholds, or the softest intensity at which sound is perceived. The following is one of the more commonly used classification systems:
|Degree of hearing loss||Hearing loss range (dB HL)|
|Normal||below -10 to 15|
|Slight||16 to 25|
|Mild||26 to 40|
|Moderate||41 to 55|
|Moderately severe||56 to 70|
|Severe||71 to 90|
It is of course a sensitive subject, but if you think someone is suffering from hearing loss, try to support them and point them in the direction of someone that can help. There are three main options for your
A qualified Hearing Aid Audiologist registered with the Health Professions Council will offer advise on improving their hearing loss. They will always advise where hearing can be improved without a hearing aid.
Their doctor will be able to discuss their hearing loss with them and refer them to their local hospital's audiology department or a specialist hearing care provider where appropriate.
Ultimately, your friend or loved one has the right to decide what's best for them, and they may choose not to act at all. You can only advise speaking to somebody, and inform them of the dangers of not acting.