ANAT auditory pathways

Question 1

where are cell bodies of CN VIII cochlear part found in?

where does it synapse

Answer 1

spiral ganglion

cochlear nuclei

Question 2

where do ascending bundles of CN VIII synapse

Answer 2

anterior subdivision of ventral cochlear nucleus

globular bushy cells and spherical bushy cells

Question 3

where do descending bundles of CN VIII synapse

Answer 3

posterior division of ventral cochlear nucleas and dorsal cochlear nucleus

(octopus cells and pyramidal cells?)

Question 4

f(x) of the different parts of the cochlear nuclei

dorsal and ventral

Answer 4

dorsal - identifying sound source elevation and
identifying complex spectral characteristics of sounds
ventral - horizontal localization of sound
anterior - globular and spherical bushy cells
posterior - octopus cells

Question 5

Monaural information

what is it

Answer 5

information about sounds at a single ear

relayed contralaterally

Question 6

Monaural tracts

Answer 6

cochlear division of CN VIII –> dorsal cochlear nuclei
–> inferior colliculus –> medial geniculate nucleus

dorsal cochlear nucleus
decussates via dorssal acoustic stria
ascend in lateral lemniscus
inferior colliculus
travel through brachium of inferior colliculus –> MGN
MGN
synapse in layer IV of primary auditory cortex (Heschl’s
gyrus)

Question 7

Binaural information

Answer 7

information about differences between sounds at both ears

Question 8

Binaural tracts

Answer 8

cochlear part of CN VIII –> ventral cochlear nuclei –> superior olivary complex –> inferior colliculus –> MGN

ventral cochlear nucleus
projects bilaterally through trapezoid body to get to
superior olivary complex
superior olivary complex
ascend in lateral lemniscus to inferior colliculus

Question 9

Conduction deafness

Answer 9

deficit related to an obstructed, or altered transformation of sound through the tympanic membrane or ossicle chain

Question 10

sensorineural (nerve) deafness

Answer 10

damage to the cochlea, cochlear part of CN VIII or the cochlear nuclei

Question 11

central deafness

Answer 11

damage to the central pathways

Question 12

what supplies the cochlea and the auditory nuclei of the pons and medulla

Answer 12

basilar a

Question 13

what supplies the inner ear and cochlear nuclei

Answer 13

internal auditory (labyrinthine) a

occlusion of AICA –> monaural hearing loss

Question 14

what supplies superior olivary complex and lateral lemniscus

Answer 14

short circumferential branches of the basilar

Question 15

what supplies the inferior colliculus

Answer 15

quadrigeminal a (ACA) and superior cerebellar a

Question 16

what supplies medial geniculate bodies

Answer 16

thalamogeniculate a

Question 17

what supplies the primary auditory and association cortices

Answer 17

M2 of MCA

Question 18

f(x) of wernicke’s

non-dominant?

Answer 18

language comprehension

interpreting non-verbal signals from other people

Question 19

f(x) of broca’s

non-dominant?

Answer 19

speech

producing non-verbal signals

Question 20

auditory agnosia

Answer 20

inability to describe a sound that has been heard

Question 21

global lesion

Answer 21

lesion of lateral sulcus
receptive and expressive deficits
reading and writing impaired
(wernickes and brocas)

Question 22

Transcortical (sensory or motor)

Answer 22

can repeat

Question 23

conduction aphasia

Answer 23

(type of fluent aphasia)
can't repeat
intact fluency
good comprehension
speech interrupted by word finding difficulties
reading intact, writing impaired