Brain stem Flashcards
What are the 3 general functions of the brainstem?
Conduit for ascending and descending tracts connecting spinal cord to forebrain
Contains important reflex centers associated with respiration, cardiovascular system, and consciousness
Contains nuclei of CN III to XII
Where are the olives (inferior olivary nuclei) located?
Posterolateral of the pyramids on the medulla
Where the hypoglossal N emerge from the brainstem?
From groove between the pyramid and olive
What structure connects the medulla to the cerebellum, located posterior to the olive?
Inferior cerebellar peduncles
Where is the posterior median sulcus?
Dorsal medulla, inferior lateral part outside of 4th ventricle
Where is the gracile tubercle (gracile nucleus)?
On either side of the posterior median sulcus on the medulla
What is the location of the cuneate tubercles (nucleus)?
Lateral to the gracile tubercles on the medulla
What is the superomedial zone?
Form the caudal part of the 4th ventricle in the medulla
What 3 elevations are seen in the superomedial zone?
Hypoglossal trigone
Vagal trigone
Vestibular area
Where is the basilar groove?
Ventral midline of bones
Houses basilar artery
Where does the trigeminal N emerge from the brainstem?
Anterolateral surface of the pons - two roots
What CNs emerge from the groove between the pons and the medulla medial to lateral?
Abducent N
Facial N (two roots)
Vestibulocochlear N
What forms the upper part of the fourth ventricle?
Posterior surface of the pons
Where is the medial eminence?
On either side of the median sulcus on the dorsal pons
Where is the locus ceruleus?
Rostral to median sulcus of dorsal pons
What is the interpeduncular fossa?
Deep depression in midline of ventral midbrain
Where is the crus cerebri?
Also called cerebral peduncle
On either side of the interpeduncular fossa of ventral midbrain
What is found in the floor of the interpeduncular fossa?
Pituitary stalk
Mammillary bodies
Posterior perforated substance
What separates the lateral surface of the midbrain from the parahippocampal gyrus?
Trochlear N
Where are the superior colliculi?
Centers for visual reflexes
On dorsal midbrain, connected to lateral geniculate body
Where are the inferior colliculi?
Centers for auditory pathways
On dorsal midbrain, connected to medial geniculate body
Where does the trochlear N emerge from the brainstem?
Dorsal midbrain, below the inferior colliculi