Brain stem

Question 1

what are the key features of the midbrain?

7 of them

Answer 1

superior and inferior colliculi
cerebral peduncles
cerebral aqueduct
red nucleus
substantia nigra
CN III and CN IV

Question 2

what are the key features of the pons?

8 of them

Answer 2

pons proper
middle cerebral peduncle
Fourth ventricle
basilar artery
CNs V, VI, VII, VIII

Question 3

what are the key features of the medulla?

8 of them

Answer 3

4th ventricle 
pyramid
olive
vertebral arteries
CNs VIII,IX,X,XI,XII

Question 4

Midbrain
oculomotor nucleus
type of nucleus, innervations and what happens if damaged?

Answer 4

somatic motor to Levator palpabrae superioris, superior, medial, inferior rectus muscles, and inferior oblique muscle
damage: causes ptosis(dropping of upper eyelid) and eve deviating down and out

Question 5

Midbrain
Edinger-Westphal nucleus
type and innervation
relfex

Answer 5

visceral motor (parasympathetic)
innervation is pupillary constrictor and ciliary muscles
pupillary light reflex

Question 6

Midbrain
Trochlear nucleus
type and innervation
damage result

Answer 6

• somatic motor to the superior oblique muscle

- damage prevents patients looking in and down

Question 7

Pons
Trigeminal motor nucleus
type and innervation
damage result

Answer 7

• branchial motor to muscles of mastication
• damage causes weakness in jaw clinching and deviation to side of lesion while opening of jaw; jaw jerk reflex
• *jaw goes to same side as damage**

Question 8

Pons
abducens nucleus
type and innervation
damage result

Answer 8

• somatic motor to the lateral rectus muscle

- damage results in double vision when looking laterally on side of lesion

Question 9

Pons
Facial motor nucleus
type and innervation
damage result

Answer 9

Branchial muscles of facial expression
-damage(nuclear and infranuclear) causes ipsilateral Bells palsy, corneal reflex.
Supranuclear damage results in contralateral Bells palsy with sparing of forehead

Question 10

Pons
Superior salivatory nucleus
type and innervation
damage result

Answer 10

Visceral motor(parasymp) to the lacrimal, nasal, palatal, submandibular salivary and sublingual salivary glands
-damage: causes dry eye, dry mucous membranes, dry mouth.

Question 11

Medulla
Hypoglossal nucleus
type and innervation
damage result

Answer 11

-Somatic motor to the muscles of the tongue
-damage causes the tongue to deviate to the side of the lesion when tongue is protruded
“lick your wounds”

Question 12

Medulla
nucleus ambiguus
type and innervation
damage result

Answer 12

Branchial motor to palatal, pharyngeal and laryngeal muscles
-damage causes soft palate to deviate contralaterally when gag reflex is elicited; swallowing difficulties; hoarse voice, gag reflex

Question 13

Medulla
Dorsal vagal nucleus
type and innervation
damage result

Answer 13

Visceral motor (para) to thoracic and abdominal viscera to the transverse colon
-damage causes reduction in parasympathetic innervation

Question 14

Medulla
Inferior salivatory nucleus
type and innervation
damage result

Answer 14

Visceral motor(para) to the parotid gland
-damage alone will likely result in no symptoms

Question 15

the quadrigeminal plate or tectum consists of what paired bodies and what is their function and where are they found?

Answer 15

superior colliculus: preliminary visual processing
inferior colliculus: auditory processing
-found on the posterior aspect of the midbrain

Question 16

what is the function of the cerebral peduncles(crus cerebri) and where are they located?

Answer 16

relay for cortico-spinal, cortico-pontine, and cortico-bulbar tracts
-they are found just lateral and anterior to the calliculi and wrap around to the anterior

Question 17

what is found in the midbrain that has the function of transporting CSF from the 3rd ventricle to the 4th ventricle?

Answer 17

cerebral aqueduct aka mesencephalic aqueduct or aqueduct of sylvius

Question 18

what is found in the midbrain at the level of the superior colliculi that is involved in motor coordination and is considered an extrapyramidal system?

Answer 18

red nucleus

Question 19

where is the supstantia nigra found and what is it involved in?

Answer 19

found the the midbrain
involved in movement and reward (addiction)
*parkinsons disease and another extrapyramidal system

Question 20

what tracts are found within the pons proper?

where is the pons proper on a crossection?

Answer 20

corticospinal and cerebellar tracts

found on the most anterior portion of the fat belly (pons)

Question 21

What is found within the middle cerebellar peduncle and what is its location relative to the pons proper?

Answer 21

contains fibers that arise from the contralateral pontine nuclei and end in the cerebellum
-located just lateral and posterior to pons proper

Question 22

where is the fourth ventricle found and what is in it?

Answer 22

within the pons and contains CSF

Communicates w/ subarachnoid space via median and lateral apertures

Question 23

basilar artery formed by what arteries and what comes of it?

Answer 23

formed by the vertebral arteries
branches: AICA, pontine arteries, Superior cerebellar artery and posterior cerebral artery
runs right down the middle of the anterior pons

Question 24

where are the pyramids found and what is in them?

Answer 24

they are found in the medulla
decussation of corticospinal tract
most anterior and medial portion of medulla

Question 25

the olive contains fibers that go where and what CN exists between the pyramid and olive?

Answer 25

the fibers course to the cerebellum

the CN XII or hypoglossal exits between them

Question 26

what branches come off the vertebral arteries and what do the two vertebral arteries form when the connect?

Answer 26

Posterior inferior cerebellar artery (PICA)

the basilar artery is formed when the two vertebral arteries connect(this occurs just rostral to the medulla)

Question 27

why is the CN VIII vestibulocochlear nerve found in both the pons and medulla?

Answer 27

because it has nucleus that descends to the medullar from the pons

Question 28

which muscles are considered branchial, which arch do they come from and what nerve innervates them?

Answer 28

muscles of mastication, 1st arch, CN V
muscles of facial expression, 2nd arch, CN VII
stylopharyngeus, 3rd arch, CN IX
palatal, pharyngeal, and laryngeal, 4th and 6th arch, CN X

Question 29

with regard to the sulcus limitans where are the sensory nuclei and where are the motor nuclei?

Answer 29

the sensory and always lateral and the motor is always medial

Question 30

what two nuclei are found in the rostral portion of the midbrain?

Answer 30

oculomotor nucleus and Edinger-Westphal nucleus

Question 31

what nucleus is found in the caudal portion of the midbrain?

Answer 31

the trochlear nucleus