Ear structures and function

eardrum (tympanic membrane)

; a thin membrane that vibrates when sound waves reach it

ear ossicles

made up of three main bones in the middle ear known at the malleus (hammer), incus (anvil) and stapes (stirrup)

sensorineural hearing loss

occurs when there is damage to the cochlea or nerve pathways from the inner ear to the brain. CANNOT be medically or surigically corrected. the most common type is permanent hearing loss.

outer ear canal

the tube through which sound travels to the eardrum

semicircular canals

three loops of fluid filled tubes that are attached to the cochlea in the inner ear. they help us to maintain our sense of balance.

pinna (auricle)

visible part of the outer ear, collects sound and directs it into the outer ear canal

conductive hearing loss

when sound is not conducted efficiently through the outer ear canal through the eardrum and the ossicles of the middle ear. Involves a reduction in sound level or ability to hear faint sounds. this type of loss can be medically or surgically corrected.

round window

situated just below the oval window that acts like a piston to transfer the vibration from the oval window to the fluid in the inner ear

oval window

small thin membranes situated between the middle ear and the inner ear that receives vibrations from the tympanic membrane via the ossicles

auditory nerve

a bundle of nerve fibers bound together that send electrical signals to the brain to be interpreted

eustachian tubes

a long narrow tube that opens in the middle ear which leads to the pharynx . Equalizes the pressure between the outer and inner ear

cochlea

a spiral shaped fluid filled inner ear structure; it is lined with cilia (tiny hairs) that move when vibrated and cause a nerve impulse to form

stirrup (stapes)

a tiny U shaped bone that passes vibrations from the stirrup (stapes) to the cochlea . this is the smallest bone in the human body

hammer (malleus)

a tiny bone that passes vibrations from the eardrum to the anvil

anvil (incus)

a tiny bone that passes vibrations from the hammer(malleus) to the stirrup (stapes)