Anatomy of the ear
The peripheral auditory system is housed where
What is the temporal bone
The inner ear consists primarily of the
What are the semi circular canals and cochlea
•These fibers of auditory nerve connect to inner hair cells and efferent fibers to outer hair cells
What are afferent fibers
•Contains bones (ossicles), muscles, ligaments, nerves
•Auditory (eustachian) tube connects middle ear cavity to the nasopharynx
What is the middle ear
•This structure collects sound energy and aids in sound localization (up-down dimension)
What is Pinna
The middle ear and inner ear are encased where?
Where is the petrous portion of the temporal bone
Produces nerve impulses in response to sound…located inside the cochlea
What is the organ of corti
•Most auditory fibers of this cranial nerve cross over to the other side of the brainstem and ascend to the cortex on that side
What is CN VIII
These are middle ear "ossicles"
What are malleus, incus , stapes
•Boundary between outer and middle ear
What is the tympanic membrane
Auditory nerve, facial nerve, and labyrinthine artery pass through this area
What is the internal auditory meatus
Sound energy transmitted to the oval window displaces the fluid (perilymph) in the scala vestibuli and this is known as what
What are traveling waves
These fiber types are primarly responsible for motor movements
What are efferent fibers?
These are the main muscles of the middle ear
What are the stapedius and tensor tympani
terminates at the tympanic membrane
What is the external auditory meatus
The peripheral auditory system consists of what
a stiff structure inside the cochlea of the inner ear that separates two fluid-filled tubes and plays a crucial role in hearing by separating sounds of different frequencies
The Basilar membrane
Pressure in the ear is equal to what?
What is force per unit area
•Contraction of this muscle occurs in response to very intense sound
What is the tensor typani
This cartilaginous landmark of the auricle, located anterior to the external acoustic meatus, helps localize sounds coming from behind.
What is Tragus
What parts of the ear are considered conductive and sensorineural respectively?
What are outer and middle ear and then inner ear
This structure is narrowest and stiffest at the base, widest and most floppy at the apex
What is the basilar membrane
This is how sound is produced
What are air vibrations → eardrum vibration → bone vibrations → fluid vibrations → nerve signals to the brain.
•Contraction of this muscle pulls footplate of stapes away from oval window and stiffens ossicular chain
What is the Stapedius
•resonates like a tube closed at one end with the first resonant frequency ~ 3000 to 3500 Hz (depending on the length)
External audtiory meatus