Brain Stem and Cerebellum Flashcards
What are the functions of the Brain stem.
1) CONDUIT = allows ascending and descending pathways to reach the thalamus and cerebellum from the spinal cord.
2) INTEGRATIVE = allows cardiovascular, respiratory and consciousness.
3) CRANIAL NERVE nuclei are here
During development; where does the midbrain orginate from?
Mesencephalon
During development ; where does the pons and cerebellum originate from?
Metencephalon
During development ; where does the medulla oblongata originate from?
Myelencephalon
what separates the 2 pyramids of the medulla?
Anterior median fissure
Interupted by decussation of the pyramids.
what is the decussation of pyramids?
the 2 pyramids contain motor fibres that run from the cortex to the spinal cord. They crossover here.
what separates the olives from the pyramids on the medulla? and what nerves emerge from here?
Anterolateral sulcus.
hypoglossal nerves emerge from here
Where do the vagus and glossopharyngeal nerves emerge from?
Posterolateral Sulcus
what forms he dorsal column pathway?
Cuneate and gracile fascicle
pathway of sensory information from body to brain
What is the function of the pyramids of the medulla?
the pyramids contain descending motor fibres
what forms at the ponto-medullary sulcus?
Anterior to the sulcus the basilar artery forms from the joining of the 2 vertebral arteries.
Superior Colliculus
associated with VISION
Inferior Colliculus
associated with HEARING
where does CN4 the trochlear nerve emerge from?
Dorsal Aspect of Brainstem.
Inferior to Inferior Colliculus (midbrain)
describe the internal structure of the brainstem
1) Tectum : lies posterior to the cerebral aqueduct. It is at the level of the midbrain and forms the Superior Colliculus and Inferior colliculus.
2) Tegmentum is anterior to the 4th ventricle. It contains the cranial nerve nuclei.
3) Basal = Cerebral Peduncles, Pons and Pyramids. Descending fibres run here.