week 6 - neuro (brainstem, blood supply) Flashcards
Which cranial nerves are from the forebrain?
Olfactory, optic
Which cranial nerves are from the midbrain?
Oculomotor and trochlear
Which cranial nerves are from the pons?
Trigeminal, abducens, facial
Which cranial nerve is from the pon/medullary border?
Vestibulocochlear
Which cranial nerves are from the medulla?
glossopharangeal, vagus, accessory, hypoglossal
Which cranial nerve is from the posterior of the brainstem?
Trochlear
Where is the rhomboid fossa?
Posterior aspect of the pons
Where do the cerebellar peduncles connect to the rest of the brain?
The posterior aspect of the pons
Where are the colliculi?
On the posterior aspect of the midbrain
Where are the cuneate and gracile fasiculus?
On the posterior aspect of the medulla
What is the role of the superior colliculi?
visual pathway
What is the role of the inferior colliculi?
Auditory pathway
Where is the interpeduncular fossa?
on the ventral aspect of the midbrain, between the crus cerebri
Where are the crus cerebri?
On the ventral aspect of the midbrain, two lateral lumps
Where are the mammillary bodies?
On the ventral aspect of the midbrain, just superior to the interpeduncular fossa, inferior to the optic tract and between the crus cerebri
Where is the bulbopontine sulcus?
The transverse sulcus between the pons and the medulla
Where is the basilar sulcus?
The midline of the ventral aspect of the pons
Where are the medullary pyramids?
On the ventral aspect of the medulla
Where are the medullary olives?
On the ventral aspect of the medulla, just lateral to the pyramids
Where do the pyramids decussate?
85% in the medulla, 15% do not decussate
What do the pyramidal tracts do?
motor to the body (corticospinal) and head (corticobulbar - cranial nerves)
What is Wallenberg syndrome?
Stroke in the lateral medulla - causing horner syndrome, diplopia, slurred speech and dizziness
What is directly involved in forming the circle of willis?
Middle cerebral, internal carotid, anterior cerebral, posterior cerebral, anterior and posterior communicating arteries
What is the facial colliculi?
On the posterior surface of the pons, It is formed by the fibres of the facial nerve from the facial nerve nucleus wrapping around the abducens nucleus
The cerebellar peduncles connect with which parts of the brain?
superior with midbrain, middle with pons, inferior with medulla
What are the nuclei of the cerebellum?
Dentate, emboliform, globose, fastigial (don’t eat greasy food)
What is the function of the vermal zone of the cerebellum?
Trunk balance and stability, input from spinocerebellar tracts, associated with fastigial nucleus
What is the function of the flocculonodular lobe?
Balance and eye movements. input from vestibulocochlear nerve and superior colliculi
What does the vestibular nuclei do?
Coordinates eye movements vis CN III, IV and VI. Also modifies position of the head via the vestibulospinal
What does the dentate nucleus do?
Regulates changes in motor planning
What is the function of the paravermal zone of the cerebellum?
Involved in skilled, volitional movements, receives inputs from spinocerebellar tracts from the limbs
What are the three layers of the cerebellar cortex?
Molecular layer, purkinje cell layer, granular layer
What is the cause of ataxic dysarthria?
atrophy of middle cerebellar peduncle
What is the cause of asynergia and ataxia?
Damage to the cerebellum
What is the function of the pineal gland?
Production of melatonin
Where is the pineal gland?
Posterior aspect of the corpus callosum, just superior to the cerebellum
Where is the tectum?
The region of the midbrain posterior to the cerebral aqueduct
Where is the tegmentum?
The anterior region of the midbrain between the cerebral aqueduct and the pars compacta of the substantia nigra (also extends throughout the whole brainstem)
What is the function of the tectum?
Auditory and visual processing
What is the function of the tegmentum?
Coordination of movement, pain processing and alertness
What is contained within the tectum?
Nuclei of the superior and inferior colliculi
What is contained within the tegmentum?
red nucleus (coordination of movement), periaqueductal grey matter (pain), connections of the reticular formation (alertness)
What are the corpora quadrigemina?
The inferior and superior colliculi of the midbrain
What does the superior colliculi connect to?
lateral geniculate body and optic tract, via the superior brachium
What does the inferior colliculi connect to?
The medial geniculate body and auditory cortex, via the inferior brachium (I AM AUDITORY)
Where are the geniculate bodies?
They project from the posterior of the pulvinar of the thalamus
What is the function of the corpora quadrigemina?
Reflexes - look towards light, turn towards a startling sound
What is the area postrema?
A circumventricular organ on the dorsal inferior surface of the medulla, ependymal cells detect toxins in the blood and act as a vomit-inducing centre with the dorsal vagal complex