cranial nuclei: Auditory and vestibular

Question 1

• VIII cranial nerve goes to the cochlear nucleus

Answer 1

auditory nuclei: medulla

Question 2

what are the two divisions of the cochlear nucleus?

Answer 2

• dorsal CN

- ventral CN

Question 3

what are the two divisions of the ventral CN?

Answer 3

anterior and posterior

Question 4

from the CN the info goes to the contralateral and ipsilateral superior olivary complex (SOC)

Answer 4

from the medulla to the pons

Question 5

what are the two divisions of the SOC?

Answer 5

medial and lateral SOC

Question 6

• the lateral lemniscus receives contralateral and ipsilateral info some from the SOC and some from the CN
• the lateral lemniscus is the main ascending auditory tract through the pons

Answer 6

from SOC fibers go to the lateral lemniscus

Question 7

• the lateral lemniscus sends info up to the inferior colliculus the auditory nuclei in the midbrain
• the inferior colliculus has two major divisions the central nucleus/core and he pericentral nucleus
• the inferior colliculus receives info from he SOC, the lateral lemniscus and he CN as well

Answer 7

auditory nuclei in the midbrain

Question 8

where is the central nucleus/core?

Answer 8

Brodmanns 17 and 18

Question 9

where is the pericentral nucleus locates?

Answer 9

Brodmann 19

Question 10

• the inferior colliculus’s primary tract is then into the ipsilateral medial geniculate body which is a nucleus of the thalamus
• there are also minor tracts going to the cerebellum the reticular formation and the superior colliculus

Answer 10

auditory nuclei in diencephalon

Question 11

• from the thalamus the info is sent to the ipsilateral primary auditory cortex
• located in the temporal lobe
• Brodmann’s area 41 and 42

Answer 11

auditory nuclei in the telecephalon

Question 12

• info carried via VIII nerve
• enters brainstem at the medulla-pons junction
• at this point the vestibular portion of the nerve terminates at different nuclei than the auditory portion of the nerve
• the nuclei form a lump on the outside of the medulla

Answer 12

vestibular nuclei

Question 13

• superior, lateral, medial, and inferior vestibular nuclei
• major tracts from the medial, lateral, and inferior go onto the cerebellum
• the cerebellum also projects info back to vestibular system, particularly concerning proprioception
• this info is constantly updated back and fourth which allows equilibrium maintenance

Answer 13

four vestibular nuclei

Question 14

• info from the superior vestibular nucleus is sent to the medial longitudinal fasciculus
• this is a fiber tract that runs midline through the medulla, pons and midbrain
• from here projections are sent to the oculomotor III, trochlear IV, abducen VI, and spinal accessory IX
• this allows for the coordination of eye movement (III, IV, VI) and head/neck (XI) movement

Answer 14

superior vestibular nuclei