How We Hear
Our ears are designed to channel in sound waves from the environment, taking sound through the ear canal and toward the eardrum in both the right and left ears. The sound waves vibrate our eardrums and are transferred into the middle ear space, the space beyond the eardrum. In each ear, the sound wave is conducted across three small bones, the hammer, the anvil, and the stirrup (collectively called the “ossicles”) that lie in the middle ear. The stirrup in each ear directs the sound wave into the cochlea, the snail-shaped structure within the inner ear space. The cochlea is filled with fluid and lined with microscopic hairs. When the stirrup moves to conduct the sound into the cochlea, its movement causes the fluid in the cochlea to vibrate. The hairs within the cochlea bend with the movement of the fluid, causing a nerve impulse to be sent through the auditory nerve (the hearing nerve) up into the brain. The brain is responsible for comparing the information received from both the left and right ears, and then translating the signal into “sound,” or meaningful information that we can use and respond to.
A hearing test measures how well your ears are functioning. At H.E.A.R.S, your hearing test will begin with otoscopic examination of the ear. Using an instrument called an otoscope, the audiologist will look into your ear canal and examine your eardrum. Obvious abnormalities (blockage caused by wax or a foreign body, fluid in the ear canal, perforated eardrum, etc.) can be observed during this part of the examination.
The evaluation continues by performing tympanometry on both ears to check if your ear canal and middle ear are healthy. Tympanometry tells us if there is an ear infection, wax, or congestion (fluid) trapped behind the eardrum. Children under five years of age tend to get occasional bouts of congestion or fluid behind the eardrum, generally occurring less frequently as the child becomes older. Often this goes undetected at home because there is no fever or pain associated with it. However, children that have middle ear fluid (called otitis media) for a long period of time may develop speech and/or learning problems. Tympanometry results are displayed in the form of a graph called a tympanogram, and are labeled under three general categories: Type A, Type B, and Type C.
- Type A tympanograms reveal that the ears are healthy. There is no fluid, wax, or congestion interfering with your hearing.
- Type B tympanograms indicate that there is fluid, congestion, or wax interfering with the your hearing. Individuals with Type B tympanograms should consult their doctors.
- Type C tympanograms indicate that you are in between Type A and Type B. This means that you are either just getting or just clearing up from fluid in the ear.
The hearing assessment continues with pure tone testing. During testing, you will be asked to respond to a series of beeps by pressing a button on you side of the soundproof booth, indicating to the audiologist on the other side of the booth that you heard the presented tone. Thresholds of your hearing sensitivity will be found and graphed on an audiogram, which will show your hearing sensitivity at a number of different pitches and volumes. Your audiologist will use the information graphed on your audiogram to determine the type and degree of your hearing loss, which will be used to plan for the appropriate management of your loss. If the audiologist feels that hearing aids or other assistive listening devices can be beneficial to managing your hearing loss, your options will be presented to you. Based on the degree of your loss, the physiology of your ear, your lifestyle, and your budgetary needs, a plan will be created to help you manage your loss.
Take the quick hearing survey below! If most or all of your answers are “half the time” or “almost always,” you should consider coming in for a hearing evaluation today!