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Med Neuro Block 3 > Corticospinal Tract > Flashcards

Flashcards in Corticospinal Tract Deck (50):
1

Three types of movements performed by Corticospinal Tract

Reflexes
automatic postural adjustments
Voluntary (goal directed, internally generated, get better with practice)

2

The Corticospinal tract has an UMN that projects to:

Lower motor neurons in the ventral horn of ALL levels of the spinal cord

3

The Corticospinal tract UMN projects to LMN in the _____ horn in which sp cord levels

Ventral horn
all levels

4

What is the function of the UMN--> LMN in the corticospinal tract

Voluntary movement of DISTAL extremeties

5

When does the corticospinal tract decussate to the other side?

At the medulla/sp cd junction

6

Which three descending motor pathways project to sp cd

Cortical structures (primary motor cortex, prefrontal motor and somatosensory and parietal)
Subcortical strucutes (basal ganglia, cerebellum, thalamus)
Brainstem

7

The UMN for the corticospinal tract begins in:

Cerebral cortex... primary motor cortex

8

What is the approximate location of cortical lesion in pt who has facial weakness?

within the longitudinal fissure of the lateral cortical surface

9

Blood supply for the lateral part of the cortex (face)

the MCA

10

What is the blood supply for the lower limbs?

ACA

11

The motor map of the cortex overlaps and exhibits plasticity meaning....

it can change with increased use or disuse of a body part (PRACTICE... you can recover use of limbs from stroke!)

12

Primary motor neurons connect to __________ that innervate a skeletal muscle via corticospinal tract

alpha motor neurons

13

The corticospinal tract will ________ flexors and __________ extensors

excite flexors
inhibit extensors

14

Four areas of cortex CST arise from

1. Primary motor cortex
2. Betz of lamina V (precnetral gyrus)
3. Premotor cortex/Supplementary Cortex
4. Pariatal lobe

15

Order the CST pass through from cortex

cortex--> corona radiata--> posterior limb of internal capsule--> middle of cerebral peduncle--> medullary pyraminds

16

CST go from Cortex --> _______--> posterior limb of internal caplse --> _________---> medullary pyramids

corona radiata
middle of cerebral peduncle

17

90% of the tracts will _______ at the cervicomedullary level and travel down the _______

decussate
Lateral corticospinal tract

18

The fibers that descend in the lateral corticospinal tract will descend in

lateral fasciculus to all cord levels

19

10% of the fibers will _______ at the cervicomedullary level and travel down the _______

stay ipsilateral
Anterior or Ventral corticospinal tract

20

Fibers that travel down the Anterior or ventral corticospinal tract decussate:

in the ventral white commisure to thoracic sp cd.

21

Lesions above the decussation result in _____ weakness

CONTRA

22

Lesions below the decussation result in______weakness

IPSI

23

The lateral wall of the third ventricle is the

thalamus

24

What lies between the caudate and putamen then alongside the thalamus

Internal capsule

25

which stroke would have more diffuse effects, corona radiata or the internal capsule

Internal capsule

26

Where in the midbrain does the CST pass through

the middle cerebral peduncle

27

What is the somatotopy of the spinal cord motor system?

All motor in the Ventral part of horn: trunk muscles more medial... extending out most lateral as digits and fine motor control

28

What is the major pathway for voluntary movement?

Corticospinal tract

29

As the Cerebral Crus goes into the Pons, what Neve is it close to?

Oculomotor Nerve III

30

What nerve sits right on top of the Medullary Pyramid?

Hypoglossal Nerve

31

What nerve lies in the Ponto/medully junction (close to start of pyramid)

Abducent Nerve

32

After the Pyramidal decussation, the Lateral Corticospinal tract will

stay lateral!, and ventral stays ventral

33

Weber Syndrome in the midbrain affects CN

III (oculomotor, vision)

34

Key CN in the pons

VI (abducens) abducting the eye

35

Medial medullary syndome in the medulla would affect CN

XII

36

A lesion in the Posterior Limb of the internal capsule would result in

Contralateral hemiplegia

37

A lesion in the cerebral peduncle or the Crus cerebri could rsult in which syndrome?

Weber Syndrome

38

Symtpoms of Weber syndrome

Contralateral paralysis of lower face/tongue/arm/leg and Ipsilateral oculomotor palsy (eye deviates laterally, ptosis, pupil is dialatead and fixed)

39

Weber syndrome could result from

Lesion in cerebral peduncle, Occulsion of PCA

40

What is the result of a CN III injury and what would cause it?

Ipsilateral oculomotor palsy:
eye deviates laterally, ptosis, pupil is dialated and fixed

41

A corticospinal tract lesion in the Cerebral peduncle would result in:

contralateral paralysis of lower face, tongue, arms and leg

42

A Lesion in the medullary pyramid is called

Medial Medullary syndrome

43

What is a possible cause of medial medullary syndrome?

Occulsion of Verterbral artery or anterior spinal artery

44

What three lesions result because of Medial medullary syndrome

Corticospinal tract lesion
CNXII lesion
Medial Lemniscus injury

45

Symptoms of Medial Medullary Syndrome

Corticospinal tract lesion: contralateral hemiparasis of arm, leg (FACE SPARED)
CNXII injury: Ipsilateral paralysis of tongue (lick wound)
Medial Lemniscus injury: Contralateral loss of touch, vibration, joint position, sensation for half of body

46

What happens to the Medial Lemniscus in a medial medullay syndrome ( occusion of vertebral or anterior spinal artery)

Medial Lemniscus injury: Contralateral loss of touch, vibration, joint position, sensation for half of body

47

What happens to the CNXII in a medial medullay syndrome ( occusion of vertebral or anterior spinal artery)

Ipsilateral paralysis of tongue

48

What happens to the Corticospinal Tract in a medial medullay syndrome ( occusion of vertebral or anterior spinal artery)

Corticospinal tract lesion: contralateral hemiparasis of arm, leg (FACE SPARED)

49

Occusion of the vertebral artery or anterior spinal artery could lead to

Medial Medullary Syndrome

50

See signs of ipsilateral spastic paralysis and an ipsilateral Babinski Sign could be

a lesion in the spinal cord on the SAME side