It consists of the pinna - the visible part of the ear - and the external auditory canal, or meatus. The middle ear transforms sound so that it can be easily detected by the inner ear. The middle ear is made up of the eardrum and ossicles. The eardrum is connected to a chain of three small bones: the malleus, incus and stapes.
These connect the eardrum to the inner ear. The inner ear sends signals to the brain. The cochlea is the snail-shaped part of the inner ear that converts sound vibrations into electrical impulses, which are sent through the auditory nerve to the brain.
When any part of the ear is damaged, sound information cannot be properly carried to the brain, which results in some degree of hearing loss.
See how it works. It is measured by audiologists, who test the Hearing Level HL of each ear using different frequencies. Hearing loss of 40 to 70 dB HL. Moderate sounds cannot be heard. Speech is perceived if the speaker raises his or her voice. Hearing becomes easier if the person can see the speaker. Some familiar sounds are still perceived. Hearing loss of 70 to 90 dB HL. Speech is perceived if the speaker speaks loudly while close to the ear.
Only loud sounds are perceived. Following a group conversation is difficult. Hearing loss of 90 to dB HL. It is impossible to hear any kind of speech, and communication is not possible. Only very loud sounds are perceived. When any part of the hearing path is damaged, sound information cannot be properly carried to the brain, resulting in some degree of hearing loss. If you or a loved one experience SSHL, treat it as an emergency and see a doctor right away. According to the National Institute on Deafness and Other Communication Disorders, about half of people who experience SSHL recover some or all of their hearing within one to two weeks from onset.
Though not all sensorineural hearing loss can be prevented, the best thing you can do is protect yourself against noise-induced hearing loss. Learn more about noise exposure and preventative measures here. People who have both conductive and sensorineural symptoms are said to have mixed hearing loss. This can happen if there is a blockage or damage to the outer or middle ear as well as the cochlea or auditory nerve in the inner ear.
Mixed hearing loss is caused by a combination of factors that contribute to conductive hearing loss and those that contribute to sensorineural hearing loss.
Hearing healthcare professionals often find it beneficial to treat the conductive factors first, since they can often be cured. If you think you might have hearing loss, the most important thing you can do is get your hearing checked by a professional as soon as possible. Just like a regular physician checkup, annual screenings will allow you to monitor your hearing health and take action as soon as any changes occur.
The first step is to connect with your local EarQ professional and make an appointment by phone or online. Put Your Hearing to the Test.
Sometimes, hearing loss happens so gradually that it can be difficult to notice at first. Chemical disturbances, through medications or metabolic changes, can affect the makeup of inner ear fluid or change its pressure or volume. If you suspect hearing loss for yourself or a family member, consider getting a hearing test to determine the level of severity. A thorough test should determine the hearing level in each ear and your ability to discriminate speech.
Hearing levels are measured in decibels dB. The lower the number for example 15 dB the better your hearing. A reading in the dB range is considered normal hearing.
Results in the 75 dB to 85 dB range indicate severe hearing loss. Speech discrimination scores in a quiet surrounding are indicated by percentages. Use of Health Topics. Conductive or sensorineural Hearing impairments are classified by what part of the process is affected. Conductive hearing loss Conductive hearing loss can be caused by blockage of the external canal, perforation of the eardrum, infections and diseases of the middle ear, and disruption or fixation of the small hearing bones.
Sometimes a surgical correction can improve the hearing. Sensorineural hearing impairment Sensorineural hearing impairment is more common and has many possible causes. Causes of sensorineural hearing impairment Noise Loud noises frequently result in temporary hearing loss.
Aging Through normal aging, most individuals lose some of their sound receptors or nerve endings. Genetics Genetic factors can play a role in how inner ear structures develop and stay healthy. Infections Viral infections can cause hearing loss in infants and adults, usually resulting in a sudden loss.
Chemicals Chemical disturbances, through medications or metabolic changes, can affect the makeup of inner ear fluid or change its pressure or volume.
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