Neuroscience Lec 10 - Medulla

Front 1

when there are cranial nerve signs where is the lesion ususally? what side?

Back 1

- lesion is usually in brainstem

- on same side as lesion

Front 2

what fibers travel in the pyramids of the medulla?

Back 2

- corticospinal fibers & corticobulbar fibers

Front 3

what do the cerebellar peduncles do?

Back 3

- strap cerebellum onto brainstem

Front 4

what does the inferior cerebellar peduncle connect?

Back 4

- major communication between medulla & cerebellum

- brings information into cerebellum from medulla & vesticular nuclei

Front 5

what do the cuneate tubercle & gracile tubercle hold?

Back 5

- cell bodies to 2nd order neurons for dorsal column tract

Front 6

what is the reticular formation? where is it present?

Back 6

- neurons that control respiration, HR, consciousness

- present in medulla, pons, midbrain

Front 7

what is the medial lemniscus?

Back 7

- part of dorsal column pathway, brings dorsal column information up to thalamus

- kind of meets up with the spinothalamic pathway in midbrain to get up to thalamus

Front 8

what is the corticobulbar pathway?

Back 8

- motor cranial nerve nuclei receive cortical input via corticobulbar pathway

- pathway is bilateral will synapse on left & right

Front 9

what is the alar vs basal plate?

Back 9

- alar plate gives rise to sensory neurons

- basal plate gives rise to motor neurons

Front 10

somatic motor nuclei are most _________, somatic sensory nuclei are most ________. visceromotor & viscerosensory are separated by what?

Back 10

- medial

- lateral

- sulcus limitans

Front 11

what is the order of the columns of CN nuclei from midline to lateral?

Back 11

- somatic motor --> branchial motor --> visceral motor --> visceral sensory --> somatic sensory --> special taste

Front 12

where is the spinothalamic vs corticospinal pathway located in the spinal cord?

Back 12

- anterolateral finiculus is the spinothalamic

- lateral faniculus is the corticospinal

Front 13

what is the descending nucleus spinal V?

Back 13

- pain & temp from face, poorly myelinated nuclei with second order neurons in this pathway

Front 14

where does the corticospinal tract dessucate?

Back 14

- in the pyramids of the caudal medulla

Front 15

does the corticospinal pathway cross above or below the dorsal column pathway in the caudal medulla?

Back 15

- corticospinal pathway crosses below

Front 16

what are the internal arcuate fibers?

Back 16

- coming from dorsal column pathway through the 2nd order neurons & cross over to form the medial lemniscus to ascend up to the thalamus

Front 17

what is the difference between the caudal & rostral medulla?

Back 17

- caudal is closed & rostral is open into 4th ventricle

Front 18

what is the inferior olivary nucleus? where is it located?

Back 18

- located in rostral medulla

- gets input from the cortex and sends it across the midline & into cerebellum

Front 19

where is the hypoglossus nucleus? what happens when it is damaged?

Back 19

- present in midline of medulla

- have equivalent of lower motor neuron lesion - ask patient to protrude tongue and will deviate to side of lesion due to weakness

Front 20

what is nucleus ambiguus? what happens when it is damaged?

Back 20

- sends fibers out through cranial nerves 9 & 10 - go to larynx, pharynx & soft palate

- lesion of these fibers will result in hoarseness of voice & difficulty swallowing

- uvula will be deviated to unaffected side

Front 21

what is the dorsal motor nucleus of X?

Back 21

- major parasympathetic nucleus of brain stem

Front 22

what is the nucleus solitarius?

Back 22

- visceral motor - receives info from the viscera including taste

- cranial nerves are 7, 9, 10

- sensory only

Front 23

what is the spinal nucleus of V?

Back 23

- descending nucleus of V

- trigeminal ganglion heading in & descend & give somatosensory to face about pain & temperature