Pons HY

Question 1

reticular formation - location/function in pons

Answer 1

Core/center
-arousal/consciousness

(in medulla: respiration, BP, HR)

Question 2

corticospinal tract - location in pons

Answer 2

always ventral

-thru pyramids of medulla

Question 3

medial lemniscus - location in pons

Answer 3

• medial
• horizontal

-joins with spinothalamic pathway

Question 4

spinothalamic tract - location in pons

Answer 4

-always lateral

Question 5

vestibular nucleus

Answer 5

• lateral
• equilibrium
• position/acceleration of head in space
• posture/muscle tone
• eye movement

Question 6

cochlear nucleus

Answer 6

• hearing
• bilateral innervation (trapezoid body)

Lesion:

• difficulty localizing sound
• difficulty eliminating background noise

Question 7

abducens nuclei

Answer 7

• midline, medial in CAUDAL pons
• lateral rectus (somatic motor)
• –moves ipsilateral eye laterally via PPRF

Question 8

facial nuclei

Answer 8

• upper facial division: bilateral innervation
• lower facial division: contralateral innervation

lesion of nucleus/nerve (LMN): paralysis of whole ipsilateral face

Question 9

lesion of CBT (UMN) of facial

Answer 9

paralysis of ipsilateral lower face

Question 10

lesion of nucleus/nerve (LMN) of facial

Answer 10

paralysis of whole ipsilateral face

Question 11

principal sensory nucleus of V

Answer 11

touch, proprioception, vibration

-of face

Question 12

motor nucleus of V

Answer 12

• muscles of mastication

- influenced by mesencephalic nucleus (midbrain)

Question 13

pontine nuclei/transverse pontine fibers

Answer 13

-form middle cerebellar peduncle

Question 14

superior cerebellar peduncle

Answer 14

-efferent pathway from cerebellum to midbrain

Question 15

middle cerebellar peduncle

Answer 15

-afferent pathway from pons to cerebellum

Question 16

CN nuclei present in the pons

Answer 16

VI: abducens
VII: facial
VIII: vestibular, cochlear
Spinal nucleus of V
Principal sensory nucleus of V
Motor Nucleus of V

Question 17

PPRF

Answer 17

for lateral gaze

PPRF: ipsilateral lateral rectus contraction

MLF: contralateral medial rectus contraction

Question 18

trigeminothalamic tract

Answer 18

• spinal nucleus of V (pain/temp of face)
• principal sensory nucleus of V (touch/proprioception)

^^ join in trigeminothalamic pathway

• no one knows where it is
• assume a problem with it = lesion in nerve/nucleus (NOT tract)