Loss of hearing occurs when the passage of sound waves to the brain is impaired. Hearing loss may be partial or complete, temporary or permanent, depending on the cause. Hearing loss is not technically the same thing as deafness, or hearing deficit. While hearing loss can lead to hearing deficit, deafness is an inability to hear that most often occurs at, or before, birth or as a result of a major illness or infection.
Hearing loss is divided into three categories: conductive hearing loss, sensorineural hearing loss, and central hearing loss.
Conductive hearing loss occurs when the passage of sound waves is impeded in the external or middle ear. It may result from factors such as earwax buildup, middle ear infection and inflammation, Paget’s disease, arthritis, or trauma to the eardrum. Sensorineural hearing loss is a consequence of damage to the structures or pathways of the inner ear. It may result from damage to the acoustic nerve (the eighth cranial nerve, also known as the auditory nerve), which carries information from the inner ear to the brain, or from damage to tiny cells called hair cells in the inner ear. The hair cells are responsible for translating sound waves into nerve impulses for transmission to the brain. If the hair cells die, they are unable to repair themselves and the resulting hearing loss is permanent.
Sensorineural hearing loss can be present from birth, or it can be caused by certain prescription medications including certain antibiotics, nonsterodial anti-inflammatory drugs (NSAIDs), aspirin taken over along period of time in high doses, quinine, viral infection of the inner ear, and Meniere’s disease. This type of hearing loss affects both the acuity and clarity of hearing. Initially, it is noticed at higher pitches, and then, as it progresses, it is noticed at lower pitches, where speech is heard. It is also possible to have mixed hearing loss, in which both conductive and sensorineural loss are present. Neural hearing loss usually occurs as a result of a brain tumor or stroke. Central hearing loss is very rare and is usually due to severe brain damage.
Hearing loss can be sudden or gradual, occurring over a period of days, weeks, or years. Infection, trauma, changes in atmospheric pressure, and earwax buildup or impaction can cause a sudden loss of hearing. Infection and inflammation often follow an upper respiratory infection or trauma to the ear, such as from the overuse or improper use of cotton swabs. Bathing or swimming in water that is overly chlorinated or contains high levels of bacteria or fungi can also lead to ear infections. Persistent and recurrent ear infections are often linked to fungal infection (candidiasis) and are frequently seen in people with allergies, cancer, diabetes, or other chronic diseases.
If hearing loss develops gradually, the individual experiencing it may be unaware of it until it reaches a fairly advanced stage. In fact, it is not uncommon for friends and family members to notice signs of hearing loss before the person experiencing it does. Some signs that may point to a hearing problem include seeming inattentiveness, unusually loud speech, irrelevant comments, inappropriate responses to questions or environmental sounds, requests for statements to be repeated, a tendency to turn one ear toward sound, and unusual voice quality.
One-third of people over the age of sixty-five have problems with their hearing. Aging is the major factor in loss of the ability to hear the full range of frequencies in everyday communication. Loss of the ability to hear high-frequency noises usually comes first. This type of age-related hearing impairment is called presbycusis. Presbycusis can be caused by a change in the blood supply to the ear due to heart disease, some diabetic conditions, or circulatory problems.
Suspected hearing deficits in infants deserve close and immediate attention, as an undiagnosed hearing impairment can lead to delayed or diminished acquisition of language skills and, possibly, learning disabilities. Risk factors for hearing loss in infancy include a family history of hearing loss; known hereditary disorders; congenital abnormalities of the ears, nose, or throat; maternal exposure to rubella or syphilis, or to ototoxic drugs such as tobramycin (Nebcin), streptomycin, gentamicin (Arraying), quinine (Quinamm), furosemide (Lasix), or ethacrynic acid (Edecrin); and birth-related problems such as prematurity, trauma and/or lack of oxygen during delivery, low birth weight, Usher syndrome, or jaundice. Otitis media (middle ear infection) is the most common cause of hearing loss in children. For the most part, this is temporary, but chronic or recurrent ear infections can cause permanent hearing loss due to inflammation and infection of the middle ear.
Sensorineural hearing loss in children can also be caused by childhood diseases such as meningitis, mumps, and rubella. Signs of hearing problems in infancy include failure to blink or startle at loud noises; failure to turn the head toward familiar sounds; a consistent ability to sleep through loud noises; greater responsiveness to loud noises than to voices; a failure to babble, coo, or squeal; and monotonal babbling. In toddlers, warning signs include failure to speak clearly by age two, showing no interest in being read to or in playing word games, habitual yelling or shrieking when communicating or playing, greater responsiveness to facial expressions than to speech, shyness or withdrawal (often misinterpreted as inattentiveness, dreaminess, or stubbornness), and frequent confusion and puzzlement. In older children, signs of hearing loss are similar to those in adulthooda failure to respond to verbal requests, inappropriate responses to questions or other sound stimuli, and a seeming inattentiveness.
Causes of hearing loss
Hearing loss caused by exposure to loud noises (noise pollution) is an increasing problem in our society today. When the delicate mechanisms of the inner ear are assaulted by loud noises, a phenomenon called temporary threshold shift (TIS) occurs. If you have ever walked away from a concert or a construction site with a buzzing or hissing in your ears, or with everything sounding as if you are underwater, you have experienced temporary threshold shift. When this condition occurs, you hear only noises above a certain level. While overnight rest usually restores normal hearing, this is a sign that damage has occurred to the hair cells in your inner ear. If this type of damage is lengthy and/or repeated, permanent threshold shift (PTS), with permanent damage and hearing loss, is the result. There are a number of terms-some clinical, some informal-used to distinguish among the sources of noiserelated hearing loss. Boilermaker’s ear is a condition caused by heavy exposure to broad-band noise. The affected individual loses the ability to hear high-frequency sounds and has difficulty in understanding spoken words. Diplacusis is a form of hearing loss experienced as sound distortionthe pitch of a given tone is heard differently by each ear. Hyperacusis is an extreme sensitivity to loud noises that can be caused by damage to the eardrum. Sociocusis is a term used to denote hearing loss from non-work-related exposure to noise. Most people who develop noise-related hearing loss say they were unaware that anything was wrong until they developed tinnitus or speech became inaudible, but in fact, the damage begins long before that and temporary threshold shift is a clear sign of it.
Noise-related hearing loss is common in train engineers, military personnel, and workers subjected to constant industrial noise, as well as in hunters and musicians, especially rock musicians.
Tinnitus is a condition that occurs in about 85 percent of people with hearing loss. It is experienced as constant or recurring ringing, buzzing, or hissing noises not caused by anything in the external environment. It is now thought that the noise originates in the brain and not in the ear, as was preViously believed. If the ear is damaged by exposure to loud noises or certain medications (including aspirin), the brain may try to compensate and end up producing electrical signals that a person hears as a ringing noise in the ears.
Natural home remedies for the treatment of hearing loss
- Echinacea aids poor equilibrium and reduces dizziness. It also fights infection and helps reduce congestion. It can be taken in tea or capsule form.
- To soothe inflammation and fight infection, mullein oil can be used as ear drops. If mullein is not available, garlic oil or liquid extract (Kyolic) may be substituted.
- Eat fresh pineapple frequently to reduce inflammation. Also include plenty of garlic, kelp, and sea vegetables in your diet.
- For an ear infection, put 2 to 4 drops of warm (not hot) liquid garlic extract in the affected ear. (If both ears are infected, do not use the same dropper for both ears, as it may spread infection.) This treatment is very helpful for children.
- Pound fenugreek seeds and put them in hot oil. Filter and cool it to a bearable temperature. This oil should be used as eardrops.
- Wash the ear with water in which neem leaves or neem bark has been boiled. This is very effective for a earache.
- For earwax buildup, clean or irrigate your ears using either a solution of 1 part vinegar to 1 part warm water, or a few drops of hydrogen peroxide. Using an eyedropper, place a few drops in your ear, allow them to settle for a minute, then drain. Repeat the process with the other ear. Do this two or three times a day. Do not use cotton swabs to clean inside the ear canal, as this can push wax further into the ear canal and exacerbate the problem. If the wax is hard and dry, apply garlic oil for a day or two to soften it. Then wash out the ear with a steady stream of warm water. Be patient, continue to irrigate the ear canal, and flush with warm water. Most cases of ear wax buildup can be treated by this method. Another method of removing excess ear wax, called ear candling, uses special candles available at health food stores. Instructions for the procedure are included with the candles. The candling procedure requires assistance, so do not attempt this by yourself.
Prevention for hearing loss
- Always wear ear protection (disposable plugs or earphone-style headset) when using loud appliances such as power tools or lawn mowers; and when you know you will be exposed to sudden loud noises, such as when shooting a gun.
- Protect your hearing when listening to music. A general guideline is to keep the volume low enough that you can easily hear the telephone and other sounds over the music. If you are using a personal stereo unit with headphones, you should be the only one able to hear your music. If someone standing next to you can hear it, it’s too loud.
- Limit your consumption of alcohol and sugars, which encourage the growth of yeast. This is particularly important if you have recurrent ear infections and have been treated with antibiotics. Also eliminate or keep to a minimum your intake of caffeine, chocolate, and sodium.