Neuro Fns Lect #14

Front 1

This serves as the anatomical landmark of the transition from the lower to the upper medulla?

Back 1

Obex

Front 2

What are the caudal and rostral boundaries of the lower medulla?

Back 2

Decussation of the pyramids (ventrally); OBEX (dorsal)

Front 3

How many representative levels are in the medulla?

Back 3

5

Front 4

These structures of the lower medulla are located on the ventral aspect and contain descending tracts from the cerebral cortex that form the ACST and LCST

Back 4

Pyramids

Front 5

Where do the LCST cros within the medulla?

Back 5

pyramidal decussations

Front 6

What is the direction of crossing fibers of the LCST in the pyramidal decussations?

Back 6

from ventromedial across midline to lateral funiculus

Front 7

This is the remaining portion of the ventral horn (at the level of the pyramidal decussation) which contains motor neurons of the lower medulla?

Back 7

Supraspinal Nucleus

Front 8

These structures appear within the fasiculus gracilis and fasiculus cuneatus, and is where primary afferents synapse?

Back 8

Nucleus gracilis and nucleus cuneatus

Front 9

This structure in the lower medulla is continous with the zone of lissauer?

Back 9

Spinal V Tract

Front 10

Lam 1-4 neurons expand to form this nucleus in the dorsal horn of the lower medulla?

Back 10

Spinal V Nucleus

Front 11

These two ascending tracts remain the same from the spinal cord into the lower medulla?

Back 11

PSCT and ASCT

Front 12

This tract changes its name to the Spinothalamic tract?

Back 12

ALSTT

Front 13

What are the three major structural mdification which take place as we ascend within the lower medulla from the "motor decussation" to the "sensory decussation"?

Back 13

Internal Arcuate Fibers; Accessory Cuneate Nucleus; Hypoglossal Nucleus

Front 14

Axons of neurons from NC and NG cross the internal arcuate fiber ventromedially and become the contralateral…?

Back 14

Medial Lemniscus

Front 15

What is the location of the upper limb equivalent to the dorsal nucleus of clark?

Back 15

external to the nucleus cuneatus (Accessory Cuneate Nucleus)

Front 16

This is positioned on each side of the midline ventral to the central canal in the "sensory decussation"?

Back 16

Hypoglossal Nucleus (motor neurons of CN 12)

Front 17

What sensory modalities are located in the FG and FC in the medulla?

Back 17

Primary afferent fibers for tactile discrimination, vibratory sense, and kinesthesis

Front 18

The nucleus cuneatus and gracilis produce what on the dorsal surface of the medulla?

Back 18

Two elevations called clava (tuberculum gracilis and tuberculum cuneatus)

Front 19

Sacral, Lumbar and lower thoracic fibers synapse onto this nucleus?

Back 19

Nucleus gracilis

Front 20

Upper thoracic and cervical fibers synapse onto this posterior column nuclei?

Back 20

Nucleus cuneatus

Front 21

Internal Arcuate fibers contain axons of neurons from these areas in the lower medulla?

Back 21

Nucleus cunneatus and nucleus gracilis

Front 22

This ascending structure is formed by decussating internal arcuate fibers?

Back 22

Medial Lemniscus

Front 23

What is the somatotopic organization of the medial lemniscus?

Back 23

Dorsal > Central > Ventral = Upper extremity > trunk > Lower extremity

Front 24

Where does the medial lemniscus project to?

Back 24

Thalamus

Front 25

Where would anterograde degeneration be seen in a unilateral lesion of the nucleus gracilis or cuneatus?

Back 25

ipsilateral internal arcuate fibers and contralateral medial lemniscus

Front 26

A unilateral lesion of the medial lemniscus would result in loss of what?

Back 26

contralateral loss of tactile discrimination, vibration, and kinesthesis

Front 27

Sensory innervation from the head region is chiefly carried to the CNS in branches of this nerve?

Back 27

Trigeminal Nerve (CN V)

Front 28

What is the sensory modality of the spinal V nucleus?

Back 28

Pain, thermal, and light touch (head region)

Front 29

What is the location of the Spinal V Nucleus?

Back 29

posterolateral region from C2 - Mid pontine levels

Front 30

Primary afferent fibers of the Spinal V Nucleus are located where?

Back 30

Trigeminal Ganglion (sensory of ear are located in ganglia of 7,9,10)

Front 31

Where do the spinal V tract axons synapse onto?

Back 31

Spinal V Nucleus

Front 32

What is the somatotopic organization of the spinal V tract and nucleus?

Back 32

Mandibular = dorsal, maxillary = central, opthalmic = ventral

Front 33

What happens to the axons that come out of the spinal V nucleus?

Back 33

They cross in the brainstem and ascend to the thalamus via the trigeminothalamic tract

Front 34

Which tract is the trigeminothalamic tract in close proximity to during its ascent to the thalamus?

Back 34

medial lemniscus

Front 35

Unilateral lesion of spinal V tarct or/and Spinal V nucleus will result in?

Back 35

ipsilateral loss of pain, thermal, and light touch in the face

Front 36

Unilateral damage to the trigeminothalamic fibers will result in?

Back 36

Contralateral loss of pain, thermal, and light touch

Front 37

What are the three trigeminal sensory nuclei?

Back 37

Spinal V nucleus, Principal sensory nucleus, and mesenchepalic nucleus of V