Brainstem Anatomy Flashcards
What is the function of the reticular formation?
maintenance of consciousness
What is the only cranial nerve not attached to the brainstem?
CN 1
What are the 3 important contents of the medulla?
Medulla:
Pyramids
Olives
Fourth Ventricle
What are the 4 important contents of the pons?
Pons:
- Basal Pons
- Middle Cerebellar
- Peduncle
- Part of 4th ventricle
What are the 4 important contents of the midbrain?
Midbrain:
Inferior/Superior Colliculi
Superior Cerebellar Peduncle
Cerebral Peduncle
Cerebral AQUEDUCT
What are the following associated with in the brainstem?
- Superior Cerebellar Peduncle (SCP)
- MCP
- ICP
- Midbrain
- Pons
- Medulla
What forms the following areas of the Posterior Fossa?
- Floor
- Roof
- Brain Divisions
- Floor = Occipital & Temporal Bone
- Roof = Tentorium
- Cerebellum & Brainstem
Where does CN 3 emerge from? What can crush it? What kind of gaze would it create
INTERPEDUNCULAR FOSSA
- Uncus
- Lateral gaze
What is the mesencephalon?
Midbrain
What is another term for the Cerebral peduncles? For the Inferior & Superior Colliculi?
- Crus Cerebri
- Corpora Quadrigemina OR
Tectum
Which colliculi are involved with hearing? Vision? Which use the medial & lateral geniculates coming from the Thalamus?
SLO AIM
Superior Colliculi uses the Lateral Geniculate for OPTIC functions (vision)
Inferior Colliculi uses MEDIAL Geniculate for Auditory function
Which cerebellar peduncles are afferent? Efferent?
Superior = EFFERENT (VSCT)
Middle & Inferior = Afferent
(inferior for DSCT &CCT)
Where are the cerebral peduncles located? What do they connect? What fibers do they contain?
Midbrain
- connect cerebrum with brainstem & SPINAL CORD
- MYLENATED fibers (white matter - appear black in stain)
What are the fibers call that are leaving the Olive of the medulla and traveling to the cerebellum?
Climbing fibers
Where do the CST fibers decussate? What kind of cells are in the CST?
- in the pyramidal tract of the MEDULLA
- Pyramidal cells (Betz cells)
Where is the tentorium located? What meningeal layer is it composed of?
POSTERIOR CRANIAL FOSSA
- DURA
What structures are lateral to the 3rd ventricle? What does the 4th ventricle look like?
THALAMUS
- diamond shaped
Where do the following nerves originate from
3, 4 , 5, 6, 7, 8, 9, 10, 11, 12
3 = Interpeduncular fossa 4 = DORSUM of brain (only one that crosses the brain as well) 5 = Basal Pons 6 = pontomedullary junction 7,8,9 = pontomedullary angle 10 = dorsal to OLIVE 12 = ventral to OLIVE(front)
11 = from cervical spinal cord on the side
What must be ripped off for us to see the 4th ventricle?
Cerebellum
Which gland (pituitary/pineal) is ventral? Dorsal?
Pituitary = ventral
pineal = dorsal
Where does the pineal gland project?
Dorsally by the 3rd ventricle
What is located near the thalamus and concerned with vision?
PULVINAR
What is the function of mamillary bodies? How are they connected to the hippocampus? Are they found ventrally or dorsally?
MEMORY
- connected via FORNIX
- degenerate with alcoholism*
VENTRAL
What are the 6 major structures found in a cross section of the CAUDAL MEDULLA (low)?
- Pyramids
- Internal Arcuate Fibers (decussating in medulla)
- N. Gracilis
- N. Cuneatus
- Spinal tract & Nucleus of 5
- Medial Lemniscus
What vertebral levels are the following associated with:
- F. Gracilis
- F. Cuneatus
- Nucleus Dorsalis (Clark’s Nucleus)
- C8-L3
- C1- C7, T1-T6
- C8-L2
(F. Cuneatus takes over
What helps afferent fibers reach Clark’s Nucleus (Dorsalis) at the level of L3 & lower?
F. Gracilis (LEGS = low)
What helps us feel pain & sensation on the face?
Spinal Trigeminal Tract & Nucleus
- from PONS
Where does the spinal trigeminal tract descend from? What ganglion does it pass?
PONS
- down to cervical cord to synapse on Spinal Trigeminal nucleus
- SEMILUNAR GANGLION