Intro to Brainstem Flashcards Preview

Nervous System: Unit III > Intro to Brainstem > Flashcards

Flashcards in Intro to Brainstem Deck (16):
1

Hallmark of a brainstem lesion

  • ipsilateral cranial nerve signs +
  • contralateral long tract (e.g. spinothalamic, corticospinal, dorsal column)

2

Cerebellum connections with the brainstem

  • attached via fiber bundles = "peduncles"
  • inferior cerebellar peduncle = spinal cord info ==> cerebellum & connects cerebellum to vestibular nucleus and inferior olive
  • middle cerebellar peduncle = cerebral cortex info ==> cerebellum via pontine nuclei
  • superior cerevellar peduncle = cerebellum info ==> cerebral cortex via thalamus

3

Components of the brainstem

  • superior to inferior:
    • midbrain
    • pons
    • medulla

4

Cranial Nerves : I - XII

  • CNI = Olfactory
  • CNII = Optic Nerve
  • CNIII = Oculomoter Nerve
  • CNIV = Trochlear Nerve
  • CNV = Trigeminal Nerve
  • CNVI = Abducens Nerve
  • CNVII = Facial Nerve
  • CNVIII = Vestibulocochlear Nerve
  • CNIX = Glossopharyngeal
  • CNX = Vagus Nerve
  • CNXI = Accesory Nerve
  • CNXII = Hypoglossal

5

Ventral portion of midbrain = 

Dorsolateral surface of midbrain = 

Dorsal aspect ventricular feature =

  • ventral surface = 
    • crus cerebri aka "cerebral peduncles"
    • exit point for CNIII (oculomotor)
  • dorsolateral surface = 
    • superior colliculi (2)
    • inferior colliculi (2)
  • dorsal aspect ventricular feature = 
    • cerebral aqueduct

6

Ventral portion of pons = 

Dorsal surface of pons = 

  • ventral portion =
  • basilar pons = bulging portion
    • coextensive w/basilar artery
  • dorals portion = surrounds ventral portion of 4th ventricle
    • embranced by superior and middle cerebellar peduncles

7

Ventral surface of medulla = 

Rostral surface of medulla =

Caudal surface of medulla =

 

  • ventral surface
    • white matter tracts = "pyramids"
  • rostral surface = floor of 4th ventricle
  • caudal surface = joins with spinal cord

8

Dorsal portion of brainstem = (name)

"tegmentum"

9

Cranial nerves arising above midbrain

  • CNI = olfactory
  • CNII = optic

10

CN arising @ midbrain

  • CN III = oculomotor
    • medial
    • emerges just superior to pons
  • CN IV = trochlear
    • arises from dorsal aspect

11

CNs arising @ pons

  • CN V = Trigeminal
    • lateral aspect
    • ~halfway between superior and inferior aspects of pons
  • CN VI = Abducens
    • medial, inferior
  • CN VII = Facial
    • just lateral to abducens, inferior
  • CN VIII = Vestibulocochlear
    • "double nerve"
    • lateral, inferior

12

CNs arising @ medulla

  •  CN IX = Glossopharyngeal
    • lateral, superior
  • CN X = Vagus
    • lateral, just inferior to CN IX
  • CN XI = Spinal Accessory
    • includes cervical nerve roots
    • extends to exit just inferior to CNX
  • CN XII = Hypoglossal
    • lateral, inferior to CN X/CN XI

13

Features of the medulla

  • inferior olive
    • ventral, superior, lateral
  • pyramids
    • ventral, medial
    • white matter tracts (corticospinal tract) running along ventral aspect
  • deccusation of the pyramids
    • crossing of pyramidal axons

14

Tract locations @ medulla

  • corticospinal = @ pyramids
  • dorsal column/medial lemniscus = ventro-medial
  • spinothalamic = lateral
  • spinal-trigeminal tract/nucleus = lateral, slightly dorsal to spinothalamic

15

Tract locations @ pons

  • corticospinal = ventral
  • dorsal column/medial lemniscus = central
  • spinothalamic = lateral, slightly dorsal

 

16

Tract locations @ midbrain

  • corticospinal = @ cerebral peduncles
  • dorsal column/medial lemniscus = ventro-lateral
  • spinothalamic = lateral, slightly dorsal