brainstem and cranial nerves

Question 1

all ascending and descending pathways pass through the…

Answer 1

brainstem

and they synapse here in relay nuclei or arise directly from or synapse in other brainstem nuclei

Question 2

how is the cerebellum connected to the brainstem

Answer 2

3 cerebellar penduncles (white fibre tracts)

Question 3

how many nuclei of cranial nerves are found in the cerebellum and which ones

Answer 3

9 cranial nerves are found here

3-12 except 11 (spinal accessory nerve)

Question 4

brainstem organisation in terms of tectum/tegmentum and bases

Answer 4

tectum (roof) - behind the central canal or ventricular system
the tegmentum is anterior to the tectum
the base of the brainstem is anterior to the tegmentum

Question 5

posterior view of the midbrain, pons and medulla contains..

Answer 5

pineal gland (small blob on top of the 4 blobs)
the upper 2 blobs are the superior colliculus
the lower 2 blobs are the inferior colliculus
the trochlear nerve runs under inferior colliculus
dorsal columns in medulla oblongata

Question 6

the anterior view of the midbrain, pons and medulla contains…

Answer 6

optic chiasm (weird line thingy at the very top) 
under it is this tiny circle = pituitary stalk
underneath that are 2 blobs stuck together = mamillary body
the thing around the mamillary body which looks like a jacket = cerebral penduncle
the medulla has medullary pyramids at the very top of the medulla
where the line of the pyramids stop = pryamidal decussation

Question 7

what are the descending tracts of the cerebral penduncles

Answer 7

corticospinal and coticobulbar

Question 8

the posterior surface of the medulla divides into…

Answer 8

open and closed

Question 9

what does the closed surface of the medulla have

Answer 9

extension of the central canal of spinal cord

Question 10

what does the canal widen to form

Answer 10

4th ventricle to open medulla

Question 11

what fibres cross between the open and closed medulla

Answer 11

corticospinal fibres

Question 12

where are upper motor neurones found

Answer 12

motor cortex

Question 13

where are lower motor neurones found

Answer 13

the anterior horn of the spinal cord

Question 14

what 2 arterial systems does the CNS blood supply come from

Answer 14

anterior and posterior

Question 15

what is the anterior arterial system

Answer 15

derived from internal carotid system (supplying most of the cerebral hemispheres)

Question 16

what is the posterior arterial system

Answer 16

derived from vertebrobasilar vessels (supplies brainstem)

Question 17

what does the circle of Willis contain

Answer 17

anterior cerebral artery
carotid artery
middle cerebral artery
posterior communicating artery
posterior cerebral artery

Question 18

what does the vertebrobasilar system include

Answer 18

superior cerebellar artery
basilar artery
anterior inferior cerebellar artery
posterior inferior cerebellar artery
anterior spinal artery
posterior spinal artery
vertebral artery

Question 19

what are general somatic afferent fibres (GSA)

Answer 19

fibres that carry general sensation from skin, muscles, joints of head and neck

Question 20

what are general somatic efferent fibres (GSE)

Answer 20

fibres that innervate skeletal muscle

Question 21

what are general visceral afferent fibres (GVA)

Answer 21

fibres that carry sensation from viscera of head, neck, thorax and abdomen

Question 22

what are general visceral efferent (GVE)

Answer 22

fibres that are preganglionic parasympathetic neurones to cranial, thoracis and abdominal viscera

Question 23

what are special somatic afferent fibres (SSA)

Answer 23

fibres that carry special senses of hearing and balance

Question 24

what are special visceral afferent (SVA)

Answer 24

fibres that carry taste sensation

Question 25

what are special visceral efferent (SVE)

Answer 25

innervate skeletal muscles of the jaw, face, larynx and pharynx

Question 26

function of cranial nerve 3 - occulomotor

Answer 26

motor to levator palpebrae superioris, superior rectus, inferior rectus, medial rectus
parasympathetic : motor to sphincter pupillae, cilliary muscles for acommodation

Question 27

function of cranial nerve 4 - trochlear

Answer 27

motor to superior oblique

Question 28

function of cranial nerve 5 - trigeminal

Answer 28

proprioception from muscles of mastication
discriminative touch and vibration from head
pain and temparature from the head
motor to muscles of mastication

Question 29

function of cranial nerve 6 - abducens

Answer 29

motor to lateral rectus

Question 30

function of cranial nerve 7 - facial

Answer 30

motor to muscles of facial expression
sensory from external auditory meatus and skin posterior to ear
parasympathetic motor to lacrimal, submandibular, sublingual glands and mucous glands of mouth and nose
taste from anterior 2/3 of tongue

Question 31

function of cranial nerve 8 - vestibulocochlear

Answer 31

balance

hearing

Question 32

function of cranial nerve 9 - glossopharyngeal

Answer 32

general sensation from posterior 1/3 tongue, tonsil, skin of external, internal surface of tympanic membrane, pharynx
chemoreceptors and baroreceptors in the carotid body, visceral afferent info from tongue and pharynx (gag)
taste from posterior 1/3 of tongue
motor to stylopharyngeaus
parasympathetic to parotid gland

Question 33

function of cranial nerve 10 - vagus

Answer 33

sensory from posterior meninges, external acoustic meatus and skin posterior to ear
sensory from larynx, trachea, oesophagus, thoracic and abdominal viscera, stretch receptors in aortic arch, chemoreceptors in aortic bodies adjacent to arch
sensory from taste buds in the epiglottis
motor to pharyngeal muscles and intrinsic muscles of larynx
parasympathetic to smooth muscles and glands of pharynx, larynx and thoracic and abdominal viscera
cardiac muscles

Question 34

function of cranial nerve 12 - hypoglossal

Answer 34

hyoglossus, genioglossus, styloglossus and all intrinsic muscles of the tongue

Question 35

what cranial nerves emerge from midbrain

Answer 35

2 and 4

Question 36

what cranial nerves emerge from pons

Answer 36

5-8

Question 37

what cranial nerves emerge from medulla

Answer 37

9, 10 and 12