Week 12 - Special Senses Flashcards
List the three compartments of the ear
external ear, middle ear, internal ear
List the structures of the external ear
Auricle (helix, lobule), external auditory canal, tympanic membrane
List the structures of the middle ear
auditory ossicles - malleus, incus, stapes in oval window
oval & round windows of the labyrinth, stapedius muscle, tensor tympani muscle
The stapedius muscle is innervated by ______
CN V - mandibular branch
The tensor tympani muscle is innervated by _______
CN VII
List the structures of the inner ear
labyrinth: bony/outer labyrinth, membranous/inner labyrinth
The bony labyrinth is lined with _______. There is ______ flowing in between bony and membranous labyrinth. Within the membranous labyrinth there is ________
periosteum
perilymph
endolymph
The stapes of the middle ear fits into what window of the labyrinth?
oval
List parts of the labyrinth and their functions
semicircular canals - rotational equilibrium
vestibule (sacculi, utricle) - straight-forward equilibrium
cochlea - hearing
The Organ of Corti is located in the ______ and represents __________
cochlea
receptors for hearing
The hearing receptors in the Organ of Corti are called ______. They are bathed in _____ and covered by _____
hair cells
endolymph
tectorial membrane
Describe the auditory pathway of first order sensory neurons
spiral ganglion -> cochlear branch of CN VIII -> cochlear nuclei of medulla oblongata (same side) and superior olivary nuclei in the pons (both sides)
The second order sensory neurons of the auditory pathway include _______
inferior coliculi in the midbrain
The third order sensory neurons of the auditory pathway include _______
medial geniculate body of the thalamus
In the auditory pathway, third order sensory neurons transmit impulses to __________
primary cortical area in the superior temporal gyrus (41, 42)
Describe the equilibrium pathway
Sensory receptors (hair cells) -> vestibular neuron bodies in vestibular ganglia -> vestibular axons of CN VIII -> vestibular nuclei of the medulla and pons -> cerebrum and cerebellum
The lateral/temporal retina absorbs light from the ______ panorama.
medial
The medial/nasal retina absorbs light from the _______ panorama.
lateral
The fibers of the optic nerve that originate from ganglion cells in the nasal half of the retina decussate in the _________ to the opposite optic tract.
optic chiasm
Each optic tract has within it axons representing the ______ of the visual field
contralateral half
Ménière’s disease is __________
a condition where endolymph swells the membranous labyrinth and nearby areas causing hearing and balance difficulty (tinnitus, vertigo, dizziness)