Practical 2 - Station 1 - Brainstem Flashcards
What 5 parts if the brain divided into during development?
- Telencephalon
- Diencephalon
- Mesencephalon
- Metencephalon
- Myelencephalon
What is in the telencephalon?
(cerebral hemispheres)
What is in the diencephalon?
(thalamus, hypothalamus)
What is in the mesencephalon?
(midbrain)
What is in the metencephalon?
(pons, cerebellum)
What is in the myelencephalon?
(medulla oblongata)
What is the forebrain made up of?
Telecephalon and the diencephalon
cerebral hemispheres, thalamus, hypothalamus
What is the midbrain made up of?
Mesencephalon
What is the hindbrain made up of?
Metencephalon anf the myelencephalon
pons, cerebellum, medulla oblongata
What is the brainstem made up of?
Medulla oblongata
pons
midbrain
What passes through the brainstem?
Ascending and descending fibre tracts
What are the cerebral peduncles and where are they?
In the midbrain of the brainstem
Massive bundles of nerve fibres descending from cerebral motor cortex to brainstem and spinal cord (e.g. corticospinal tract)
Where is the midbrain seen?
Short so little can be seen unless mid-sagittal section
What is the appearance of the pons like?
Bridge like
sharp demarcation rostrally and caudally
ridged appearance
Which cranial nerves are associated with the pons?
CN V-VIII
What is one the ventral surface of the medulla?
Pyramids
Where does the corticospinal tract decussate?
Medullary pyramids - ventral surface of medulla in brainstem
What is the medulla a continuation of and where?
Spinal cord through foramen magnum
What is the inferior olive?
Lateral to rostral part of medullary pyramids
oval swellings
associated with cerbellum
What cranial nerves are associated with the medulla?
CN IX-XII
Which cranial nerves emerge lateral to the inferior olive?
glossopharyngeal and vagus
Which cranial nerves emerge between inferior olive and pyramids?
hypoglossal
What are the colliculi?
Inferior and superior On dorsal surface of midbrain paired swellings buried beneath overlying cerebral hemispheres inferior - auditory info superior - optic info (both integration centres)
Where do the cuneate and the gracilis lie?
Either side of the most caudal part of the 4th ventricle
What is the obex?
Where 4th ventricle opens from - central canal, 1/3 of way up medulla
Where does the CSF of the 4th ventricle drain to?
Into central canal of spinal cord inferiorly
Into cerebral aqueduct superiorly
What is the major feature of the midbrain seen in a coronal section?
Cerebral peduncles
What is the major feature of the pons seen in a coronal section?
4th ventricle
What is the effect of the 4th ventricle opening and closing?
When open - rostral medulla opens to cerebellum
when closed - forms central canal for spinal cord and caudal medulla considered closed
What does the blood supply to the brainstem arise from?
Vertebral arteries
What do the vertebral arteries form?
Basilar artery
Where does the basilar artery run?
Entire length of pons
Where does the basilar artery split and into what?
Pontine-midbrain junction
Into posterior cerebral artery
What does the Posterior cerebral artery give off?
Several branches:
Anterior inferior cerebellar artery
superior cerebellar artery
