Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuroscience > Lab 7 Structures > Flashcards

Lab 7 Structures Flashcards

1
Q

what are the 2 spinal cord targets of the ventral gray matter?

A
  • lateral motorneurons (MNs) and interneurons (INs)
  • medial motorneurons (MNs) and interneurons (INs)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where do dorsolateral spinal cord pathways terminate? movement type?

A
  • terminate/synapse on lateral MNs and INs
  • serving single limb movements
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

where do ventromedial spinal cord pathways terminate? movement type?

A
  • terminate/synapse on medial MNs and INs
  • serving axial/proximal limb girdle muscles
  • info shared with medial MNs/INs on one side is shared with opposite side
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the function of the lateral corticospinal tract?

A
  • serves limb muscles
  • enables fractionation of movement (fine motor control/coordinated movement) of fingers, hands, UE
  • modulate sensory info
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

origin of 1st neuron

CST

A
  • precentral gyrus (motor/premotor: 60%)
  • postcentral gyrus: 40%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

projections of 1st neuron

CST

A

cerebral white matter, internal capsule, cerebral peduncles through ventral pons/medulla as “pyramids”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

crossing of 1st neuron

CST

A

pyramidal decussation of lower medulla (90% of fibers cross to become lateral CST in spinal cord)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

termination of 1st neuron

CST

A
  • lateral MN/IN of ventral horn of spinal cord
  • some to dorsal horn neurons/intermediate gray
  • connects to outgoing alpha motor neuron
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

where do the ventral corticospinal tract fibers come from?

A

10% of lateral corticospinal tract fibers that do not cross at pyramidal decussation but stay ipsilateral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

where does ventral corticospinal tract synapse?

A

medial MNs and INs (shares info with MN/IN on contralateral side)

uncrossed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does ventral corticospinal tract serve?

A

serves bilateral axial/trunk muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the function of the rubrospinal tract?

A
  • facilitate MN that innervate large mucle movements/fine motor control of UE
  • primarily serves cervical regions (greater influence on flexor muscles/inhibits extensors muscles)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

where does red nucleus receive major input from?

A

primary/premotor areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

origin of 1st neuron

RuST

A

arises from Red nucleus located in midbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

projections of 1st neuron

RuST

A

passes through contralateral midbrain, pons, medulla on its way to cervical levels of spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

crossing of 1st neuron

RuST

A

fibers cross immediately upon exiting Red nucleus

17
Q

termination of 1st neuron

RuST

A

terminates on lateral MNs/INs of ventral horn at primarily cervical spinal levels

18
Q

what is the function of the vestibulospinal tract?

A

convey impulses from labyrinth

19
Q

how many/what are the tracts that comprise vestibulospinal tract?

A
  • medial
  • lateral
20
Q

what is the function of the medial vestibulospinal tract?

A
  • activates LMN associated with spinal accessory nerve
  • rotating/lifting of head and shoulder blade
  • movements appropriate for orientation of individual during altered posture/balance
21
Q

origin of 1st neuron

medial VST

A

medial vestibular nucleus

22
Q

projections of 1st neuron

medial VST

A

exits medial vestibular nucleus and descends in white matter pathway → medial longitduinal fasciculus (MLF)

23
Q

crossing of 1st neuron

medial VST

A

primary tract does NOT cross

24
Q

termination of 1st neuron

medial VST

A

terminates on ipsilateral medial MN/IN of ventral horn primarily at cervical levels

25
Q

what is the function of the lateral vestibulospinal tract?

A
  • important for maintenance of upright posture/balance via excitation of antigravity/extensor muscles
  • mainly of trunk/ipsilateral limb girdle muscles
26
Q

origin of 1st neuron

lateral VST

A

lateral vestibular nucleus

27
Q

projections of 1st neuron

lateral VST

A

exits nucleus/descends in white matter pathway

28
Q

crossing of 1st neuron

lateral VST

A

primary tract does NOT cross

29
Q

termination of 1st neuron

lateral VST

A

terminates on ipsilateral medial MN/IN of ventral horn primarily at all spinal levels

30
Q

what is the function of the reticulospinal tract?

A
  • coordinates trunk/proximal muscle response during limb movement via balancing actions between extensors and flexors
  • lateral RST → role in suppressing extensor activity
  • medial RST → role in facilitating extensor activity
31
Q

what are propriospinal tracts?

A
  • interneurons forming white matter pathway surrounding perimeter of ventral horn
  • relay/shares info across a few (short) or many (long) spinal segments
  • cell body in 1 spinal segment and axon terminating in another spinal segment
32
Q

what is the function of short propriospinal tract neurons?

A
  • connect neighboring segments
  • travel dorsolaterally
  • tend to communicate between lateral motor neurons (info from descending LCST and RuST)
33
Q

what is the function of long propriospinal tract neurons?

A
  • travel longer distances to remote spinal segments
  • travel ventromedially
  • tend to communicate between medial motor neurons (info from VST, RST-like)
34
Q

what is the corticobulbar tract?

A

collectively refers to any descending CN related motor axons from cerebral cortex traveling to respective contralateral nuclei which in turn gives rise to respective cranial nerves

35
Q

path of corticobulbar tract

A

lateral aspect of motor cortex (precentral gyrus) and association areas → CN nuclei of contralateral brainstem

36
Q

what is the function of the motor component of the descending trigeminal pathway?

A

smaller component of trigeminothalamic tract which innervates skeletal muscle (muscles of mastication)

37
Q

what is the path of the descending motor trigeminal pathway?

A

motor fibers from motor nucleus of V → foramen ovale → skull → supply muscles of mastication

38
Q

label descending pathways

A

Neuroscience (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions