Ear Flashcards
What region of the ear ends at tympanic membrane and includes auricle (aka pinna) and auditory canal (aka external acoustic meatus)?
External Ear
What region of the ear has an air-filled space that houses the auditory ossicles
Malleus, incus & stapes
-Includes opening to pharyngotympanic tube (or auditory tube; formerly Eustachian tube)
-Equalizes air pressure in middle ear to air pressure in atmosphere
Middle Ear (aka Tympanic Cavity)
What region of the ear consists of channels & membranes
-cochlea (hearing)
-semicircular canals & vestibule (equilibrium)?
Inner Ear
Receptors for Hearing and Equilibrium are both located within the ear and are what kind of sensor receptor?
mechanoreceptors
What are the auditory ossicles ?
Middle Ear
malleus, incus & stapes
What amplifies and transmits energy of vibrations striking tympanic membrane to the oval window of the cochlea ?
Middle Ear
auditory ossicles
What is it called when muscles that contract reflexively in response to loud sounds to dampen vibrations and minimize damage to structures within cochlea?
Middle Ear
tympanic reflex
What connects to pharynx and equalizes air pressure in middle ear to atmospheric pressure?
Middle Ear
Pharyngotympanic Tube
What is an air-filled cavity within petrous region
of temporal bone?
Middle Ear
What is a flexible membrane that allows fluid within cochlea to vibrate?
Middle ear
Round window
What part of the ear contains the cochlea
and semicircular canals & vestibule ?
Inner Ear
what contains receptors for hearing?
cochlea
What contains receptors for equilibrium?
semicircular canals & vestibule
What is snail-shaped chamber within the petrous region of temporal bone?
Cochlea
What is the cochlea divided into three fluid-filled chambers (scalae) by what?
vestibular and basilar membranes:
What of the three fluid-filled chambers (scalae) receives energy of vibrations via oval window?
Scala vestibuli
What is also called the Cochlear Duct?
Scala media
What of the three fluid-filled chambers (scalae) terminates at round window?
Scala tympani
Contains endolymph fluid
-Contains the mechanoreceptors for hearing within the Spiral Organ
-Features a 3rd membrane: tectorial membrane
Scala media (cochlear duct)
What is connected at tip of the spiral of cochlea to form one long chamber
Contain perilymph fluid?
Scala vestibuli & Scala tympani
What kind of sensory receptor has ribbon of hair cells on top of the basilar membrane?
mechanoreceptors
Vibrations of perilymph within scala vestibuli and scala tympani cause basilar membrane to vibrate so that? and which step is this
stereocilia (on hair cells) bend against tectorial membrane
also step 5
Sound waves (energy) in air cause vibrations of tympanic membrane is which step in pathway of hearing?
step 1
which step in pathway of hearing is the energy is transferred (and amplified) by the ossicles?
step 2
which step in pathway of hearing is energy then passed from stapes through oval window to perilymph within scala vestibuli?
step 3
which step in pathway of hearing energy travels in perilymph of scala vestibuli, then returns via perilymph of scala tympani?
step 4
Most auditory impulses are transmitted by the cochlear branch of the?
Vestibulocochlear Nerve (CN VIII), to the medulla oblongata, then to the thalamus
What is essentially the awareness of orientation and changes in head position
“Equilibrium” is about detecting changes in motion or position; not simply “keeping your balance”.
What detects linear acceleration and static equilibrium/stationary orientation. (Often simplified to static equilibrium)?
Vestibule: Maculae
Vestibule subdivided into what two parts?
Saccule: vertical macula
Utricle: horizontal macula
What also has a patch of epithelium featuring hair cells (mechanoreceptors)?
Macula
Information about changes in head position & linear acceleration is encoded in the frequency of impulses emitted by?
maculae
Located in slight enlargements and at the bases of the semicircular canals?
Cristae Ampullares
Composed of a bundle of hair cells (mechanoreceptors) covered by a gelatinous mass called the ampullary cupula
Crista ampullaris
As rotational motion changes, fluid in the semicircular canals pulls on the cupula, which affects the frequency of impulses generated by the hair cells.
Crista ampullaris
Information about the pull on the hairs is encoded in the frequency of action potentials sent to the brain on the vestibular branch of CN
Crista ampullaris
