Approximately 15% of American adults (or 37.5 million people) report some trouble hearing. To many of us, hearing loss is understood as one condition; the truth of the matter is that hearing loss can manifest in a number of different ways, depending on what type of damage has occurred and where it has occurred in the ear. Let’s take a look at the anatomy and physiology of the ear to gain a better understanding of how hearing loss — and the ear in general — works.
The outer ear consists of the pinna or auricle. This refers to the visible part of the ear, such as the earlobe and cartilage. The canal leading to the eardrum is referred to as the external auditory canal or tube. When a sound is made outside the outer ear, the sound waves, or vibrations, travel down the external auditory canal and strike the eardrum.
The eardrum, or tympanic membrane, divides the outer ear from the middle ear. The middle ear (also called the tympanic cavity) is comprised of the following:
- Ossicles: Ossicles describe the very small bones — malleus, incus, and stapes — that are connected and transmit and amplify sound waves to the inner ear.
- Eustachian tube: The eustachian tube is a canal that links the middle ear with the back of the nose. It helps to equalize pressure (which is necessary for the proper transfer of sound waves) and also drains the middle ear of fluid.
The inner ear consists of three components: the cochlea, which contains the nerves for hearing, and the vestibule and semicircular canals, both of which contain receptors for balance.
How Does It Work?
Once sound has entered the external auditory canal and struck the eardrum, the eardrum vibrates. These vibrations travel to the ossicles, which amplify the sound and send the waves to the inner ear and into the cochlea. The sound waves are then converted into electrical impulses, which the auditory nerve sends to the brain; the brain then translates these signals into sound.
If any damage at any point in this sound journey can disrupt the process in different ways. Some may be fixed or improved with the use of Lyric hearing aids or other forms of digital technology, some can be fixed or improved through surgery, and others cannot be changed. Only through hearing evaluations and hearing tests can ENTs determine the source of the problem and how to move forward.
ENT and Audiology Associates is happy to provide hearing evaluations for patients concerned about hearing loss. Whether for yourself or your child, our hearing evaluations will be able to determine the cause of the problem. Call us at (919)782-9003 to make an appointment today.