Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neuro Mini Exam > Corticobulbospinal Tracts & Basal Ganglia Motor Systems I > Flashcards

Corticobulbospinal Tracts & Basal Ganglia Motor Systems I Flashcards

(74 cards)

Start Studying
1
Q

GSE

A

somatic motor system
-descending tract

voluntary control of skeletal m.

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

GVE

A

visceral motor system

-autonomic nervous system

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

motor system

A

motivation - frontal lobes
motor plan - premotor cortex
action - primary motor cortex

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

motivation

A

coming up with idea for motor plan

  • need input:
  • sensory stimuli (parietal motor area)
  • emotions/memory (limbic)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

motor plan

A 
module or blueprint for movement
-what muscles, what order, what timing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

premotor cortex

A

brodmans areas 6 and 8 lateral

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

supplementary cortex

A

brodmans areas 6 and 8 medial

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

action

A

UMN - from primary motor cortex and brainstem nuclei

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

UMN

A

influence LMNs
-spinal cord and cranial nerve

all UMNs converge on LMNs to produce movement

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

final common pathway

A

LMNs

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

alpha-lower motor neurons

A 
ventral horn and cranial nerve motor nuclei
synapse on skeletal m.
always excitatory
release ACh
target ipsilateral
large cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

gamma-lower motor neurons

A

muscle spindle

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

baseline activity

A

allows for fine adjustment
-in alpha LMNs

sets muscle tone

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

inputs to LMNs

A

local reflex arc
local pattern generators
UMN input

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

motor unit

A

all muscle fibers innervated by single LMN

  • size related to function
  • fine control vs. power
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

small motor unit

A

less fibers innervated

-fine control

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

large motor unit

A

1000 fibers/neuron - power control

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

each muscle fiber

A

only innervated by 1 LMN

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

individual muscle

A

have motor units of various sizes

-although certain sizes may predominate

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

action potential

A

all or none

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

regulation of muscle contraction strength?

A

AP frequency

recruitment of motor units

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

size principle

A

recruit small > large motor units

small first**

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

UMN

A

influence LMNs

  • directly
  • or indirectly
  • excitatory or inhibitory
  • never synapse on muscle**
  • cell bodies in cerebral cortex and brainstem nuclei
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

8 different UMN pathways

A

2 from primary cortex

6 from brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
lateral motor system
distal limb movement | -precise movement
26
medial motor system
proximal limb movement | -postural movement
27
lateral vs. medial
lateral - lateral funiculus | medial - anterior funiculus
28
influence on UMNs?
basal nuclei association cortex cerebellum
29
corticobulbar tract
cortex to brainstem
30
non-cortical UMN systems
reflex - postural movements -in brainstem -input from cortex influences these systems (gain voluntary control)
31
cortical UMN systems
distal limb movements | -fine movement
32
cortical UMN pathways
lateral corticospinal -cortex to spinal cord b/l corticobulbar tract
33
corticospinal tract lateral
largest tract of humans contralateral projection fine, fractionated movement
34
course of UMN on corticospinal tract
``` internal capsule cerebral peduncles (midbrain) longitudinal fibers of pons (pons) pyramids (medulla) pyramidal decussation lateral corticospinal tract ```
35
brodmans area 4
primary motor cortex | precentral gyrus
36
voluntary motor movement
posterior limb of internal capsule facial expression - genu upper limb - anterior lower limb - posterior
37
premotor cortex
lateral brodmans area 6 and 8 - motor planning - active at START of movement
38
supplementary cortex
medial brodmans areas 6 and 8 interconnected with contralateral side -bimanual movements active right before movement takes place
39
corticobulbar tract
terminates in brainstem influence cranial LMNs also to UMN nuclei -voluntary control of proximal muscles
40
cranial nerve motor nuclei
most receive input from both right and left cortex
41
corticobulbar influence on brainstem UMNs
vestibular nuclei reticular nuclei red nucleus give rise to medial motor systems -proximal limb
42
LMN damage signs
hypo to areflexis hypo to atonia paralysis/paresis - flaccid rapid, severe atrophy
43
partial paralysis
NO actually a paresis
44
neurogenic atrophy
due to loss of LMN
45
spontaneous EMG changes
with LMN damage
46
fasciculations
can see visually twitching
47
fibrillations
with EMG
48
UMN damage signs
``` normal - hyperreflexia hypertonia pathological reflexia (babinski) spastic paralysis disuse atrophy (slower) ``` few EMG changes
49
babinski
is a pathological reflex - stroking of foot - UMN damage - toes flare is abnormal - curling normal
50
hyperreflexia with UMN damage?
1. loss of normal inhibitory background 2. sprouting of local afferents - increased input from the initial primary afferent imput 3. receptors to membrane
51
denervation hypersensitivity
increased expression of receptors on surface of LMNs and interneurons
52
partial paralysis
NO | paresis
53
plegia
stroke
54
hemi
half
55
para
pair of limbs
56
quadra
four limbs
57
stroke lesions
affects many different systems
58
damage to corticospinal systems
levels below lesion LMN signs at lesion level UMN signs inferior to lesion
59
lesion above decussation
contralateral signs
60
lesion below decussation
ipsilateral signs
61
extrapyramidal system
non-contrical UMN system
62
non-cortical UMN systems
proximal limb - reflex posture - also voluntary control - corticobulbar tract
63
medial vestibulospinal tract
descending medial longitudinal fasciculus
64
anterior corticospinal tract
technically a cortical UMN tract | -but, its bilaterally, neck muscles, posture function
65
rubrospinal tract
lateral motor system | -begins in brainstem
66
rubrospinal tract
cell bodies in red nucleus - axons decussate in midbrain - descend contralaterally in lateral funiculus -to cervical cord only * *distal muscles of arm - arm/forearm flexors very small in humans
67
vestibulospinal tracts
medial and lateral tracts
68
medial vestibulospinal tract
aka descend MLF cell bodies in medial/inferior vestibular nucleus -axons descend bilaterally through cervical and upper thoracic **neck muscles, head posture
69
lateral vestibulospinal tract
cell bodies in lateral vestibular nucleus -axons descend ipsilateral ** antigravity muscles entire cord to trunk posture *** damage - ipsilateral deficits
70
medial longitudinal fasciculus
ascending cell bodies in medial.inferior vestibular nucleus * *ascends to innervate III, IV, VI - extraocular muscles of eye **bilateral
71
reticulospinal tract
medial and lateral cell bodies - reticular formation back up when corticospinal fibers are damaged (theory)
72
pontine reticulospinal tract
medial **ipsilateral
73
medullar reticulospinal tract
lateral **bilateral
74
tectospinal tract
superior colliculus - cell bodies - axons decussate in midbrain - descend contralateral end in cervical levels **neck, postural muscles **visual grasp reflex

Neuro Mini Exam (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions