The ears are a pair of sensory organs whose primary functions are hearing and balance.
They are divided into three portions: the outer ear, the middle ear, and the inner ear.
Each has an intricate structure of bones, nerves, and muscles.
Verywell
Healthcare providers use a variety of tools to examine the ears and measure how well they’re functioning.
Anatomy
The ears are two sensory organs.
They have two main functions: hearing and balance.
Each ear is divided into an outer, middle, and inner section that have distinct structures.
It is composed of a membrane attached by fibrous cartilage to the surrounding bone.
The inner surface is curved toward the middle ear and connects with the malleus bone.
It’s lined with mucous and helps regulate pressure around the eardrum so that sound waves can be transferred.
Inner Ear
The inner ear is a bony labyrinth that is filled with a fluid calledperilymph.
Hearing
The shape of the outer ear directs sound waves from the environment to the ear canal.
These waves are then directed toward the tympanic membrane (eardrum), which causes it to vibrate.
This stimulates tiny hairs on the organ of Corti, a small structure in thecochlea.
This stimulation is translated into electrical signals that are delivered to the auditory nerves of the brain for processing.
Balance
Sense of balance and position is regulated by the semicircular canals in the inner ear.
Each is filled with fluid and sensors.
When your head changes position, the fluid moves and also moves the sensors.
Those sensors transmit information on your position along the vestibular nerve to your brain.
Your brain uses this intel to send signals to your muscles to keep you balanced.
As the head rotates, the endolymph is displaced, exciting the cells and generating a sense of balance.
Ear Conditions
Many health conditions can affect how the ear functions.
Each ear consists of an outer, middle, and inner portion.
All three parts of the ear are involved in hearing.
Several health conditions can affect the ears, including Meniere’s disease, tinnitus, and infection.
A healthcare provider can diagnose some ear problems by examining the ear with an otoscope.
Bruss DM, Shohet JA.Neuroanatomy, Ear.
[Updated 2023 Apr 3].
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
Available from: https://www.ncbi.nlm.nih.gov/books/NBK551658/
Vaskovic J.Ear.
National Library of Medicine.Tympanic Membrane.
Bell D, Gaillard F.Eustachian tube: Radiology reference article.
2019;9(1).
doi:10.1186/s41935-019-0111-0
InformedHealth.org [Internet].
[Updated 2023 Sep 25].
Available from: https://www.ncbi.nlm.nih.gov/books/NBK279394/
National Library of Medicine.Tinnitus.
National Institutes of Health.What is Meniere’s disease?
American Academy of Family Physicians.Ear Infection.
American Academy of Family Physicians.Otitis Externa (Swimmer’s Ear).
Sevy JO, Hohman MH, Singh A.Cerumen Impaction Removal.
[Updated 2023 Mar 1].
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
Available from: https://www.ncbi.nlm.nih.gov/books/NBK448155/
Hohman MH, Jamal Z, Krogmann RJ, et al.Auricular Hematoma.
[Updated 2024 May 1].
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
Available from: https://www.ncbi.nlm.nih.gov/books/NBK531499/
Dolhi N, Weimer AD.Tympanic Membrane Perforation.
[Updated 2023 Aug 14].
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
Available from: https://www.ncbi.nlm.nih.gov/books/NBK557887/
American Academy of Family Physicians.Eustachian Tube Dysfunction.
National Library of Medicine.Perichondritis.
InformedHealth.org [Internet].
[Updated 2023 Jun 13].
Centers for Disease Control and Prevention.Preventing Noise-Induced Hearing Loss.
Centers for Disease Control and Prevention.Preventing Swimmer’s Ear.
