Neuro lecture 7 Flashcards
In the neural tube and eventual spinal cord the alar plate, is in what direction in relation to the sulcus limitans? what is the functions of the alar plate?
Dorsal to the sulcus limitans and largely afferent (sensory)
In the neural tube and eventual spinal cord the basal plate, is in what direction in relation to the sulcus limitans? what is the function of the basal plate?
Ventrally to the sulcus limitans and largely efferent (motor).
In brainstem development the dorsal portion of the neural tube (alar plate) rotates laterally, what significance does this play as far as location of certain cranial nerves?
this is the reason why the sensory cranial nerves are more lateral versus the primary motor CN are medially in location
During brainstem development what does the central canal enlarge to become?
4th ventricle
The midbrain contains which CN, ventrally? And what two other important structures, ventrally?
peduncles, interpeduncular fossa and CN III ventrally
Which part of the brainstem houses the basilar groove? what is the importance of this groove?
pons and it houses the basilar artery
The pons contains which CN, ventrally? which important structures, ventrally?
ventral aspects of the middle cerebellar peduncles (along with CN V-VIII)
what is the only cranial nerve that emerges from the preolivary sulcus? and why?
CN XII because this nerve is only motor (mostly tongue movement) and therefore lies medially
The midbrain dorsally contains what CN? what important structures dorsally?
Superior and Inferior Colliculi (corpora quadrigemina). CN IV
what are the 4 afferent ascending tracts of the brainstem?
Dorsal Colum-Medial Lemniscal System, spinothalamic tract, lateral lemniscus, and trigeminal leminscus
describe what the dorsal column-medial lemniscal system is responsible for
this is an ascending tract from the spinal cord to the body with synapses between the cuneate and gracile fasaciculi and nuclei.
describe the spinothalamic tract (or anerolateral system)
carries pain
describe the lateral lemniscus
audition
Trigeminal lemniscus
sensory from the face
name the two important efferent descending tracts
cortiobulbar and corticospinal
Reticular formation contains several elongated cell groups throughout the brainstem. Name some of the functions of this distinct cell groups
Arousal, coordination of chewing, licking or sucking, swallowing, vasomotor, inspiration, vomiting, expiration and inspiration
Give the reasoning why someone with a brain injury, however the brain stem is still intact, can still lick swallow or lick/
because the reticular fibers that are responsible for these actions are in the brainstem and the brainstem is still intact.
A defect in what results in the patient being unable to touch their nose to your finger? (they will either under shoot or over shoot)
cerebellar tract, the exact tract will be covered in later lectures. but many motor and sensory systems communicate with the cerebellum and the brainstem mediates all such communications.
The Anterior Inferior Cerebellar Arteries (AICA) emerge laterally from the basilar artery supply which CNs?
CN VII and VIII
what group of arteries supply the core and lateral aspects of the pons?
Pontine Arteries
what supplies the caudal midbrain?
Superior Cerebellar Arteries
which artery is associated with CN IV
Superior Cerebellar Arteries
which artery supplies CN III?
Posterior Cerebral Arteries
what are the three arteries that supply the midbrain?
posterior cerebral, superior cerebellar and posterior communicating (which again comes from the internal carotid artery)
what is the blood supply of the medulla?
PICA, AICA and Anterior Spinal (medial)
Occlusion of what artery or branches of this artery results in Wallenberg Syndrome?
PICA or branches of PICA, to the dorsolateral medulla
Name some of the deficits seen in a patient with lateral medullary syndrome
Contralateral loss of pain and thermal sense on body
Ipsilateral loss of pain and thermal sense on body
Dysphagia, soft palate paralysis, horsiness and diminished gag reflex
Ipsilateral miosis, ptosis, anhidrosis, flushing of face)
Ataxia to the ipsilateral side
Why is dysphagia and dysarthria seen in patients with lateral medullary syndrome?
Efferents of CN IX and X are present in the medulla
