Ear Lab Study Guide

What is the ear composed of?

Outer (external)

Middle

Inner (internal) parts

What do the outer structures do?

Gather sound waves and direct them inward to the eardrum (tympanic membrane)

What do the middle structures do?

Transmits vibrations in turn from the eardrum to the inner ear, where the hearing receptors are located

As they are stimulated, these receptors initiate impulses that are conducted over the vestibulocochlear nerve into the auditory cortex of the brain, where the impulses are interpreted and the sensations of hearing are created

What is the Rinne test?

To assess possible conduction deafness by comparing bone and air conduction

If hearing is normal, the sound (from air conduction) will be heard again; if there is conductive impairment, sound will not be heard

What is Weber test?

Used to distinguish possible conduction or sensory deafness

What is conductive impairment?

Involves outer or middle ear defects

Hearing aids can improve hearing for conductive deafness because bone conduction transmits the sound into the inner ear

Surgery could possibly correct this type of defect

What is the auditory ossicle attached to the eardrum?

Malleus

What is the air-filled space containing auditory ossicles within middle ear?

Tympanic cavity

What contacts hairs of hearing receptors?

Tectorial membrane

What leads from oval window to apex of cochlea and contains perilymph?

Scala vestibuli

What is the s-shaped tube leading to the eardrum?

External acoustic meatus

What is the cone-shaped, semitransparent membrane attached to the malleus?

Eardrum

What is the auditory ossicle attached to the oval window?

Stapes

What is the tube containing endolymph within bony labrynth?

Membranous labryinth

What is the bony canal of inner ear in temporal bone?

Bony labyrinth

What connects the middle ear and pharynx?

Auditory tube

What extends from apex of cochlea to round window and contains perilymph?

Scala tympani