Drive - ear and auditory processes Flashcards
How many sections can the ear be divided into and what are the names of these sections?
3
outer ear, middle ear and inner ear
What does sound first enter the ear by?
Pinna (or auricle) –> exterior part of the ear
What is the shape of the pinna and external auditory canal designed to do?
Amplify and direct the sound
What causes the tympanic membrane to vibrate?
The air molecules pushing against the membrane
At what rate does the tympanic membrane vibrate if exposed to low frequency sounds?
Slowly
At what rate does the tympanic membrane vibrate if exposed to high frequency sounds?
Rapidly
What marks the end of the external ear and start of the middle ear?
Tympanic membrane
In what bone is the middle ear located?
Temporal bone
What provides sensation to the middle ear?
Glossopharyngeal cranial nerve (CN 9)
What exposes the middle ear to atmospheric pressure?
The Eustachian tube
What connects the middle ear to the pharynx
The Eustachian tube
How are vibrations of the tympanic membrane transmitted to the inner ear?
Through a moveable (slightly) chain of 3 bones
What are the names of the 3 bones of the middle ear?
Malleus, incus and stapes
What is the name of/the type of joints found between the bones of the ear?
Synovial joints
What marks the end of the middle ear and start of the inner ear?
Oval window
What can lessen the amount of energy transmitted to the inner ear?
The tensor tympani and stapedius
What is tensor tympani muscle innervated by?
Mandibular branch of the trigeminal nerve (CN 5)
What is stapedius muscle innervated by?
Crania`l nerve 7 (facial cranial nerve)
What is the purpose of the muscles of the middle ear?
To protect the delicate receptor apparatus in the inner ear from damaged caused by continuous loud noise
What is the inner ear also known as?
Cochlea
Briefly describe the structure and location of the cochlea?
A spiral shaped, fluid-filled space in the temporal bone
What is the cochlear duct?
A membranous tube which contains the sensory receptors of the auditory system
What is the name of the fluid filling the cochlear duct?
endolymph
What is the name of the fluid filling the area surrounding the cochlear duct?
perilymph
