Auditory pathway

Question 1

where is the auditory pathway located int he skull?

Answer 1

the petrous part of the temporal bone

Question 2

why is the middle ear a high risk space?

Answer 2

IT is connected to nasopharynx and mastoid air cells so prone to infection
internal jugular vein lies inferior creating a risk of thrombosis
internal carotid arter lies anterior - link to pulsatile tinnitus

Question 3

what are the three cavities in the petrous part of the temporal bone?

Answer 3

vestibule
semicircular canal
cochlea

Question 4

what type of fluid does the cochlea contain?

Answer 4

PERILYMPH

Question 5

what type of fluid does the cochlear duct contain?

Answer 5

ENDOLYMPH

Question 6

what is the cochlear duct?

Answer 6

a membranous sac running through the cochlear

filled with endolymph

Question 7

what are the two chambers the cochlear duct separates the cochlea into?

Answer 7

the scala vestibuli and scala tympani

Question 8

where does the scala vestibuli lie in relation to the cochlear duct?

Answer 8

above the cochlear duct

Question 9

where does the scala tympani lie in relation to the cochlear duct?

Answer 9

below the cochlear duct

Question 10

what is the helicotrema?

Answer 10

the apex of the cochlea where the scala vestibuli and scala tympani are continuous

Question 11

what is the roof of the cochlear duct formed by?

Answer 11

the vestibular membrane

Question 12

what is the floor of the cochlear duct formed from?

Answer 12

the basement or basilar membrane

Question 13

what is the auditory receptor?

Answer 13

the spiral organ of corti

Question 14

where is the spiral organ of corti located?

Answer 14

on the basilar membrane

Question 15

what do the primary auditory fibres do in the auditory pathway

Answer 15

they form the cochlear nerve which becomes part of the vestibulocochlear nerve that enters the brainstem at the cerebellopontine angle

Question 16

where does the primary auditory neurone synapse with the secondary?

Answer 16

in ventral and dorsal cochlea nuclei

Question 17

where does neuron pass to after the cochlear nuclei?

Answer 17

the superior olivary nucleus

Question 18

where does the neuron pass after the superior olivary nucleus?

Answer 18

the inferior colliculus - this is in the midbrain and fibres may cross here

Question 19

where does it go after the inferior colliculus?

Answer 19

medial geniculate nucleus

Question 20

where does it go after the medial geniculate nucleus of the thalamus?

Answer 20

Heschl’s gyrus of cerebral cortex

Question 21

where does the neurone travel in the lateral lemniscus?

Answer 21

between the superior olivary nucleus and the inferior colliculus

Question 22

where does the neuron travel in the inferior brachium?

Answer 22

from the inferior colliculus to the medial geniculate nucleus

Question 23

where is the neuron travelling in the trapezoid body

Answer 23

from the cochlear nuclei to the superior olivary nucleus

Question 24

what is the basics of the auditory pathway?

Answer 24

from the cochlear nuclei the neurone travels in the trapezoid body to the superior olivary nucleus. the neurone then travels in the lateral lemniscus to the inferior colliculus. the neurone then travels in the inferior brachium to the medial geniculate nucleus. then from the medial geniculate nucleus to heschl’s gyrus in the cortex