org. of brainstem Flashcards
(34 cards)
____________ : all the ascending and descending pathway fibres have to pass through here to get to the brain
Conduit
Cranial Nerves ____ and ____ are not attached to brainstem
1 and 2
one function of brianstem is ____________
Integration : respiration , cardiaovascular, control, consciousness, sleep (reticular functions)
There are 3 subdivisions of brainstem ______ , __________ and _________
3 main subdivisions of brainstem:
Midbrain (rostral and caudal)
pons “bridge” (rostral and caudal)
Medulla (rostral and caudal)
Medulla has two subdivions :
____ and ____
Medulla (rostral and caudal):
- caudal is “closed” and only flows with spinal cord, rostral end is “open to fourth ventricle”
- Obex - where 4th ventricle becomes continues with central canal (a “V”)
the ___________ contains the pyramids together with part of the central canal. in its caudal half and part of the fourth ventricle in its rostral half.
medulla
the________ contains the basal pons and part of fourth ventricle but only the caudal pons is physically attached too the cerebellum
pons
the_________ contains cerebral peduncles and cerebral aqueduct and superior and inferior Colliculi
midbrain
_________ on posterior side of mid brain, _______ in middle and _________ on anterior side.
Tectum , tegmentum, cerebral peduncles
In the pons no _______ , _______ now posterior side, and pons is anterior “appendage”
tectum, tegmentum
____________ still the posterior side in medulla , pons is gone, the ______ are anterior side with the _________
tegmentum , pyramids , olives
Define the 3 major pathways and their functions
Corticospinal tract (voluntary movement)
Spinothalamic tract (pain and temperature)
Posterior columns (touch sensation and proprioception)
-__________ descends from motor strip down to spinal cord (on anterior side of brain stem). Through the _______ , _____ , and ______ , the fibers cross at the ________ and head down the spinal cord as the lateral __________ .
Corticospinal tract (voluntary movement) - descends from motor strip down to spinal cord (on anterior side of brain stem). Through the internal capsular cerebral peduncles, basal pons, and pyramids, the fibers cross at the spinomedullary junction and head down the spinal cord as the lateral corticospinal tracts.
_____________ - ascends from spinal cord up through brainstem to the thalamus (on anterior lateral side of Tegmentum)
Spinothalamic tract (pain and temperature)
_____________ - ascend the posterior spinal cord and end in the medulla (in the gracilis nucleus and the cuneatus nucleus) to become medial lemniscus which ascends to the thalamus.
Posterior columns (touch sensation and proprioception)
Define gneral features of Caudal Medulla
1- Caudal Medulla (Closed end)
end of spinal cord.
from cuneatus and gracilis nucleus fibers cross the midline and form the contralateral medial lemniscus (this is the sensory crossing)
spinothalamic tract in the tegmentum
Pyramid append off the anterior side,
Reticular formation in the center.
Define the general features of Rostral Medulla
- Rostral Medulla (open end)
section from obex to cerebellar peduncles
contains the inferior olivary nucleus and part of Forth Ventricle
Define general features of Caudal Pons
Caudal Pons
Physically connected to the cerebellum btw the cerebellar peduncles
Inferior olivary nucleus ends medial lemniscus still here,
lots of fibers here (pyramidal tract, spinothalamic, CST .. )
Fibers originate and go to cortex
Pons is bridge (to Cb, from brain to spinal cord, left/right crossings)
Define general features of Rostral pons
Rostral pons
- Not directly connected to Cb, still touches 4th ventricle, cerebral aquaduct.
- Pons has several nuclei and crossing tracts, major fiber crossing center (like CC)
Define general features of Caudal Midbrain
Caudal Midbrain
Tectum = superior and inferior colliculi
caudal midbrain contains inferior collicuulo (auditory)
superior cerebellar peduncles cross here
periaquaductal gray begins (pain control)
pons is gone now and instead is cerebral peduncles (where the CST travels)
Define general features of Rostral midbrain
Rostral midbrain
contains superior colliculi (vision)
red nucleus and substantia nigra (important brainstem nuclei)
thalamus and spinal glad are nearby
______________ : Not so much a structure but a collection of connections that meme the core of the brainstem
Reticular formation
what are the three major zones of Reticular formation
Three major zones :
Raphe nuclei (“seam” on midline)
Gigantocellular reticular nucleus (or medial zone)
Lateral zone (reflexes and visceral functions)
Reticular formation has two reticulospinal tracts:
1- ___________. - (orientation ? )
2- ___________ - (orientation ?)
1- pontine reticularspional tract. - medial
2- medullary reticuspino reat - lateral
