Brainscape's Knowledge GenomeTM

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


See full index

Neuroscience Module 2 > Descending Pathways (handout based) > Flashcards

Descending Pathways (handout based) Flashcards

0
Q

Originate in: Cerebral cortex, Cerebellum & Brainstem

A

Upper Motor Neurons

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

Are entirely within the CNS; Form descending tracts

A

Upper Motor Neurons

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

Begin in CNS; Made up of alpha motor neurons (A-α)

A

Lower Motor Neurons

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

From anterior horns of spinal cord

A

Lower Motor Neurons

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

From brainstem cranial nerve nuclei

A

Lower Motor Neurons

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

Make up spinal and cranial nerves

A

Lower Motor Neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Classified according to where they synapse in the ventral horn (UMN); Innervate postural and girdle muscles

A

Medial activation system

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

Classified according to where they synapse in the ventral horn (UMN); Associated with distally located muscles used for fine movements

A

Lateral activation system

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

Classified according to where they synapse in the ventral horn (UMN); Facilitate local reflex arcs

A

Nonspecific activating system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

the most important descending tract

A

Corticospinal tract

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

descends through all levels of the neuraxis except the cerebellum

A

Corticospinal tract

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

arises primarily from area 4, and 6, 3,1 and 2

A

Corticospinal tract

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

passes through the internal capsule, the cerebral peduncle, the basis pontis, and the pyramids of the medulla oblongata

A

Corticospinal tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

in the caudal medulla, about 75 to 90% of the fibers decussate to form the lateral CST in the lateral funiculus of the SC

A

Corticospinal tract

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

about 8 % of fibers remain uncrossed and form the anterior CST (Türck’s bundle) in the anterior funiculus

A

Corticospinal tract

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

Fibers in the anterior CST decussate at segmental spinal levels

A

Corticospinal tract

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

roughly about 98 percent of fibers in the pyramidal tract are crossed; remaining 2 percent remain ipsilateral and form the tract of Barnes

A

Corticospinal tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

fibers terminate on motor neurons in the lateral part of the ventral horn that supply the distal limb musculature

A

Lateral corticospinal tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

fibers terminate on motor neurons in the medial part of the ventral horn that supply the neck, the trunk, and the proximal limb musculature

A

Anterior corticospinal tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

constitutes the largest component of the cortically originating descending fiber system

A

Corticopontocerebellar tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

has been estimated to contain approx 19M fibers, in contrast to the pyramidal tract, which contains approx 1 M

A

Corticopontocerebellar tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

originates from wide areas of the cerebral cortex, but primarily from the primary sensory and motor cortices, and descends in the internal capsule, cerebral peduncle, and basis pontis, from which its fibers project on pontinenuclei

A

Corticopontocerebellar tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

it plays a role in the rapid correction of movement

A

Corticopontocerebellar tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

lesions result to ataxia that occurs contralateralto frontal or temporal lobe pathology

A

Corticopontocerebellar tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Innervates the head; Most fibers terminate in reticular formation near cranial nerve nuclei

A

Corticobulbar tract

25
Q

Corticobulbar tract

A

face areas of the cerebral cortex ➡️ genu of the internal capsule ➡️cerebral peduncle (occupy a dorsolateralcorner of the CST segment as well as a small area in the medial part of the base of the peduncle) ➡️ basis pontis(where they intermix with corticospinalfibers) and pyramid but do not reach the spinal cord

26
Q

The majority of cranial nerve nuclei receive bilateral cortical input

A

Corticobulbar tract

27
Q

Direct corticostriateprojections reach the neostriatumvia the internal and external capsules

A

Corticostriate fibers

28
Q

from the prefrontal cortex, cingulate gyrus, olfactory cortex, hippocampus, and septal area

A

Corticohypothalamic fibers

29
Q

reach the hypothalamus via the internal capsule

A

Corticohypothalamic fibers

30
Q

considered by some as an indirect CST -because of the similarity in the site of termination of both tracts, and because the red nucleus receives an input from the cortex

A

Rubrospinal tract

31
Q

function of this tract is not well understood; it is believed to play a role in the turning of the head in response to light stimulation

A

Tectospinal tract

32
Q

neurons of origin in the superior colliculuscross in the dorsal tegmentaldecussationand descend throughout the neuraxis to occupy a position in the anterior funiculusof the cervical spinal cord

A

Tectospinal tract

33
Q

Fibers of this tract terminate on neurons in laminaeVI, VII, and VIII

A

Tectospinal tract

34
Q

from the lateral vestibular nucleus, descends ipsilaterally in the pons, medulla, and spinal cord, where it occupies a position in the lateral funiculus

A

Lateral VestibulospinalTract

35
Q

terminates on interneurons in laminaeVII and VIII, with some direct terminations on alpha motor neuron dendrites in the same laminae

A

Lateral Vestibulospinal Tract

36
Q

facilitates extensor motor neurons and inhibits flexor motor neurons

A

Lateral vestibulospinal tract

37
Q

Origin in the medial vestibular nucleus

A

Medial vestibulospinal tract

38
Q

fibers join the ipsilateral and contralateral medial longitudinal fasciculus, descend in the anterior funiculus of the cervical cord segments, and terminate on neurons in laminaeVII and VIII

A

Medial vestibulospinal Tract

39
Q

plays a role in controlling head position

A

Medial vestibulospinal tract

40
Q

The neurons of origin of these tracts are located in the reticular formation of the pons and medulla oblongata

A

Reticulospinal tract

41
Q

they modify sensory activity through their interaction with spinothalamic neurons in the dorsal horn

A

Reticulospinal tract

42
Q

originate predominantly from the hypothalamus

A

Descending Autonomic Pathway

43
Q

are small-caliber fibers that follow a polysynaptic route and are scattered diffusely in the anterolateralfuniculusof the spinal cord

A

Descending autonomic pathway

44
Q

project on neurons in the intermediolateralcell column

A

Descending autonomic pathway

45
Q

Lesions of this system result in autonomic disturbances

A

Descending Autonomic Pathway

46
Q

Serotonergicfibers from the raphenucleus of the medulla oblongata

A

Descending Monoaminergic Pathways

47
Q

Noradrenergic fibers from the nucleus locus ceruleusin the rostralponsand caudal midbrain

A

Descending monoaminergic pathway

48
Q

Enkephalinergic fibers from the periaqueductal gray matter in midbrain

A

Descending Monoaminergic pathway

49
Q

descend in the lateral and anterior funiculi both ipsilateral and contralateral to their site of origin

A

Descending monoaminergic pathway

50
Q

descend in the lateral and anterior funiculiboth ipsilateraland contralateralto their site of origin

A

Descending Monoaminergic pathway

51
Q

The CST facilitates _______ motor neurons and inhibit _______ motor neurons

A

Flexor; extensor

52
Q

The CST descends through all levels of the neuraxis except the __________.

A

Cerebellum

53
Q

The CST passes through the ____________ of the internal capsule

A

posterior limb

54
Q

The anterior CST is also referred to as __________.

A

turck’s bundle

55
Q

The remaining 2% of the CST that remains uncrossed throughout its course is referred to as the ___________.

A

tract of Barnes

56
Q

The __________________ constitutes by far the largest component of the cortically originating descending fiber system

A

corticopontocerebellar tract

57
Q

Considered as indirect CST

A

Rubrospinal tract

58
Q

is believed to play a role in the turning of the head in response to light stimulation

A

Tectospinal tract

59
Q

___________________ facilitates extensor motor neurons and inhibits flexor motor neurons

A

Lateral Vestibulospinal tract

Neuroscience Module 2 (3 decks)

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