3 Brainstem and cerebellum Flashcards
What is the gross anatomy of the ventral medulla oblongata?
Pyramids separated by anterior median fissure. Interrupted by decussation of the pyramids.
Anterolateral sulcus separates pyramids from olives.
Posterolateral sulcus dorsal to olive.
What is the gross anatomy of the dorsal medulla oblongata?
Central canal opens to IV ventricle at obex. Divides medulla into closed and open. Floor is rhomboid fossa (nuclei).
Gracile and cuneate tubercles (cell bodies) and fascicles (axons).
Which artery runs through a groove on the ventral pons?
Basilar artery.
The cerebellar peduncles connect to the cerebellum. From where does each originate?
Superior: midbrain.
Middle: pons.
Inferior: medulla.
What are the colliculi on the dorsal midbrain associated with?
Superior: visual pathway.
Inferior: auditory pathway.
Where does the hypoglossal nerve originate?
Medulla: between pyramid and olives.
Where do the vagus and glossopharyngeal nerves emerge?
Dorsal to the olives on the medulla.
Which nerves originate from the cerebellopontine angle?
Facial, vestibulocochlear, abducens, pontomedullary.
Where does the trigeminal nerve originate?
Middle of the ventral surface of the pons.
Where does the occulomotor nerve emerge?
Interpeduncluar fossa.
Where does the trochlear nerve emerge?
Inferior to inferior colliculi on DORSAL surface of midbrain.
What are the three layers of the brainstem?
What do they contain?
Tectum.
Tegmentum - cranial nerve nuclei + tract, reticular formation, ascending/descending pathways.
Basal-descending fibres form cerebral cortex.
What does the reticular formation comprise of?
Reticular nuclei (descending motor).
Autonomic centres.
Cells giving rise to Ascending Reticular Activating System.
What does the reticular formation control?
Modulates pain.
Sleep wake cycle.
Arousal.
