Test for Hearing
It's easy for us to take normal hearing for granted. We go through our day expecting to hear running water in the sink, understanding a conversation on the phone and watching the television with ease. However, if you lose your hearing you'll realize how much you rely on your ears to live happily.
Get your hearing tested by an audiologist to find out if you have a hearing loss. He will check your ears and administer a number of tests that include pure-tone air and bone conduction audiometry.
Air Conduction Audiometry
Sound that travels through airwaves is called air conduction. Your ear collects air-conducted sounds, then channels them through the outer ear (ear canal and eardrum), middle ear and the inner ear.
In an air conduction test you will wear headphones and hear tones. When you hear the tones you will indicate that you heard them by raising your hand or pushing a "response" button.
Some tones will be high-pitched (shrill or treble) and some low-pitched (deep or bass), but they will all gradually become soft. You will need to indicate that you heard them no matter how soft or distant they become.
Bone Conduction Audiometry
Sound can travel through vibration of the bones in your skull. You hear bone-conducted sounds directly from the inner ear, where the sense organ for hearing (cochlea) and the hearing (auditory) nerve are located.
In a bone conduction test you will hear the same tones through a bone vibrator that is placed on the mastoid bone behind your ear. You will need to respond in the same way that you did for the air conduction test.
Types of Hearing Loss
The air conduction and bone conduction tests will show the type of hearing loss that you have.
If you can hear bone-conducted sounds better than air-conducted sounds, you have a "conductive hearing loss." This means that your inner ear is functioning normally but something is blocking the sound from travelling through outer sections of your ear, such as the outer and middle ear.
If your air conduction and bone conduction hearing are the same, then you have a "sensorineural hearing loss." In this condition, sound passes normally through the outer and middle ear. It is your inner ear that does not work properly. The problem could be from the sense organ for hearing (cochlea), the hearing (auditory) nerve or both.
Sometimes all three sections of the ear (outer, middle and inner ear) do not work properly. In that case, you would have a "mixed hearing loss" because you are unable to hear air-conducted and bone-conducted sounds.
Degree and Pitch of Hearing Loss
The pure-tone tests of air and bone conduction will tell the severity of your hearing loss and at which pitches or frequencies. You have normal hearing if you can hear sounds at 25 decibels (dB) or softer from the low to high frequencies.
Considerations
Pure-tone tests of air and bone conduction provide basic information about your hearing. Your audiologist will administer more extensive tests if any problem is suspected.
Tags: bone conduction, hearing loss, your hearing, bone-conducted sounds, conduction test, outer middle, through outer
