Parts of the ear How ears hear Ears and balance Common ear problems Where to get help. The ear has two important roles. It is our organ of hearing and our organ of balance. Parts of the ear The ear is made up of three different parts, including: the outer ear — this is the part you can see. Its shape helps to collect sound waves. The lining of the ear canal is coated with wax, a type of lubrication that stops the tissue from drying out, as well as helping to fight infection and clearing dead skin from the ear the middle ear — is made up of the ear drum and three small bones.
These amplify and carry the sound waves to the inner ear the inner ear — sound waves are changed into electrical impulses and sent to the brain. The organs of balance are located here too. How ears hear Sound waves are vibrations through the air.
The vibration of the eardrum causes movement of the three bones in the middle ear. These bones move against the cochlea the hearing organ and pass the vibrations to thousands of special hair cells inside it. The hair cells then send the sound as an electrical signal along the nerve to the brain, where we perceive the sound our brain interprets the signal as sound.
Ears and balance Our sense of balance is controlled by signals to the brain from three sensory systems: vestibular system — inner ear vision proprioception — movement sensors in the skin, muscle and joints. Common ear problems Some common ear problems include: deafness — can be permanent or temporary, mild or significant.
Can be due to many causes, including aging, disease and injury ear infection — inflammation, often caused by bacteria dizziness — this is often used to describe symptoms ranging from a sense that the patient or the room is spinning or moving vertigo , to a loss of balance, giddiness, unsteadiness, light-headedness, or weakness tinnitus — a sensation of ringing or other noises in the ears wax — a build-up of wax can cause temporary deafness. Sound waves cause the eardrum to vibrate.
The vibrations from the eardrum set the ossicles into motion. The ossicles are actually tiny bones — the smallest in the human body. The three bones are named after their shapes: the malleus hammer , incus anvil and stapes stirrup. The ossicles further amplify the sound. The tiny stapes bone attaches to the oval window that connects the middle ear to the inner ear. The Eustachian tube, which opens into the middle ear, is responsible for equalizing the pressure between the air outside the ear and that within the middle ear.
The sound waves enter the inner ear and then into the cochlea, a snail-shaped organ. The ear has three main parts: external ear, middle ear and inner ear. They all have different, but important, features that facilitate hearing and balance. The external ear, also called the auricle or pinna, is the loop of cartilage and skin that is attached to the outside of the head.
It works much like a megaphone. Sound waves are funneled through the external ear and piped into the external auditory canal, according to Nebraska Medicine. The auditory canal is the part of the ear hole that can easily be seen when looking at an ear up-close. The sound waves pass through the auditory canal and reach the tympanic membrane, better known as the eardrum.
Just like when a drum is hit by a drumstick, the thin sheet of connective tissue vibrates when sound waves strike it. The vibrations pass through the tympanic membrane and enter the middle ear, also called the tympanic cavity.
The tympanic cavity is lined with mucosa and filled with air and the auditory ossicles, which are three tiny bones called the malleus hammer , incus anvil , and stapes stirrup , according to Encyclopedia Britannica. As the bones vibrate, the stapes pushes a structure called the oval window in and out, according to the National Library of Medicine NLM.
This action is passed on to the inner ear and the cochlea, a fluid-filled, spiral-shaped structure that contains the spiral organ of Corti, which is the receptor organ for hearing. Tiny hair cells in this organ translate the vibrations into electrical impulses that are carried to the brain by sensory nerves.
The Eustachian tube, or pharyngotympanic tube, equalizes air pressure in the middle ear with the air pressure in the atmosphere. This process helps humans retain their balance. The vestibular complex, in the inner ear, is also important to balance because it contains receptors that regulate a sense of equilibrium. The inner ear is connected to the vestibulocochlear nerve, which carries sound and equilibrium information to the brain.
Ears are delicate organs that can be damaged by physical injuries, bacteria or even changes in the environment. Ear infections are the most common illness in babies and younger children, according to the NLM.
Common symptoms of ear infections are drainage from the ear, hearing loss, earache, fever, headache, pain in the ear and a feeling of fullness in the ear, according to the American Academy of Family Physicians.
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