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Flashcards in Brainstem Centers Deck (57):
1

Cortical Structures that send input to the spinal coard are

primary motor cortex
prefrontal cortex
somatosensory and parietal association cortex

2

Subcortical structures that send input to the sp cd are:

basal ganglia
cerebellum
thalamus

3

Rubrospinal tract:
Many small __________ neurons in the red nucleus project to inferior olive

parvocells

4

Neurons in the rubrospinal tract decussate at the level of the

Midbrain at the ventral tegmental decussation

5

The rubrospinal tract begins in

the midbrain at the red nucleus... then decussates right away in the ventral tegmental decussation

6

Once the inferior olivary nucleus recieve the rubrospinal tract, it sends input to the :

cerebellum or the (olivo-cerebellar tract)

7

Info from olive to cerebellum from rubrospinal tract is to

modulate cerebellum activity ( participates in learning and memory fnx of cerebellum)

8

rubrospinal: from cerebellum info goes to _____ and send contralateral to red nucleus

thalamus

9

Red nucleus via olivary nucleus will provide feedback loop to cerebellum to allow for:

feedback loop to allow adaption of cerebellar circuits
~~ keeps movements non-jerky

10

Decorticate Posturing/Rigidity seen when

cortical input to red nucleus is eliminated while cerebellar to red nuclues and rubrospinal is intact

11

Decorticate posture:
Cortical input to red nucleus is:
Cerebellar input to red nucleus is:
Rubrospinal tract is:

ELIMATED
intact
intact

12

In Decorticate posture/Rigitidy we see

upper limbs flexed to core and extention of lower limbs
cortex can no longer communated with brain stem

13

Decorticate posture is due to damage in the:

upper midbrain

14

Lower midbrain damage-->

Decerebrate posturing

15

Symptoms of decerebrate syndrome/lower midbrain damage

Patient extends upper and lower limbs

16

patients extends upper and lower limbs... damage in

lower midbrain

17

Benedikts sydrome is:

unilateral lesion of red nuclues in the midbrain

18

Symptoms of benedikts syndrome

CN III injury: ipsilateral oculomotor palsy (eye deviates laterally, ptosis, pupil is fixed and dialated)
Contralateral tremor

19

CN III injury: ipsilateral oculomotor palsy (eye deviates laterally, ptosis, pupil is fixed and dialated)
Contralateral tremor

Benedikts syndrome or unilateral lesion of red nucleus

20

rubrospinal tract lesion usually occurs in conjunction with:

corticospinal tract lesions

21

Pathway that facilitates reflexive turning movments of the eyes and head and upward gazee

Tectospinal tract

22

_________fibers arise in retina, visual cortex and inferior paretal lobes to project to superior colliculus

Corticotectal fibers

23

Tectospinal fibers start in the ______ and decussate in the _______

superior colliculus
dorsal tegmentum
(in the midbrain)

24

Tectospinal fiberes end in the ipsi/contralateral cervicle spinal cord at the _________

Contralateral
CN XI nucleus with sternodcleomastoid

25

Additional fibers from superior colliculus (part of tectospinal) project here to control exraoccular upward gaze

pontime paramedian reticular fomration-->MLF

26

Pairnauads syndrome/Dorsal midbrain syndrome/Collicular syndrome

lesion in region of superior colliculi or posterior commisure leads to eye abnormalities

27

Lesion in the supeiror colliculi or posterior commisure leads to eye abnormalities

Collicular syndrome/Parinauds syndrome/Dorsal midbrain

28

Symptoms of Parinuads syndrome

(lesion of superor colliculi)
Loss of upward gaze
large, irregular pupils w/ light-near dissociation
-eyelid abnormalities (retract or ptosis)
convergance-retraction-nystagmus

29

(lesion of superor colliculi)
impaired visual gaze
large, irregular pupils w/ light-near dissociation (pupils don't constrict with light but do with accomidations)
-eyelid abnormalities (retract or ptosis)
convergance-retraction-nystagmus

symptoms of parinurads syndrome

30

causes of Parinuads syndrome

Pineal tumor, hydrocephalus

31

Input to superior colliculi

visual cortex

32

Inputs to teh vestibular nuclei

vestibular nerve and cerebellum

33

Cell bodies in the vestibular nuclei w/in brainstem

Lateral vestibulospinal tract

34

Lateral vestibulospinal tract projects ipsi/contralateral within _________ to ALL levels of sp cd

Ipsilaterally
anterior folliculus

35

Lateral vestibulospinal tract functions

innervates extensor (antigravity) muscles in trunk/lower limbs for balance

36

Lesion of vestibular nerve or vestibular nucleus-->

stumbling and or falling toward SIDE of lesion

37

Causes of Lateral Medullary syndrome

occlusion of vertebral artery or PICA

38

Symptoms of Lateral Medullary Syndrome

Side of lesion: dysphagia, dysarthria, lower gag reflex, loss of pain and temp from face, vertigo, nausea and vomiting, nystagmus
Contralateral to lesion: loss of pain/temp from body

39

Side of lesion: dysphagia, dysarthria, lower gag reflex, loss of pain and temp from face, vertigo, nausea and vomiting, nystagmus
Contralateral to lesion: loss of pain/temp from body

Lateral medullary symtom

40

What cuases the dysphagia, dysarthria, and loss of gag reflex from lateral medullary sydnrome

nuclues ambiguis of CN XI and X on medulla

41

see a checkerboard pattern of loss of pain and temp from face (ipsilateral) and body (contralateral)

lateral medullary syndrome ( PICA or vertebral artery occulsion)

42

Input to medial vestibulospinal nucleus

vestibular nuclei and cerebellum

43

MVST description:
cell bodies in vestibular nuclie are w/in brainstem and projects to _______ within anterior funiclus to :

sp cd
and LMNs associated with spinal accessory nerve

44

projectes to cervical spinal cord and to LMNs associated with spinal accessory nerve

MVST

45

Functionof MVST

adjust head postion in response to posture change
coordiates eye movement with each other
Vestibuloccular reflex

46

what adjust head position in response to posture change, coordinates eye movment together and a VOR

medial vestibular tract

47

What other CNs do MVST project to through the MLF

CN III, IV, VI to coordiante eye movements with each other

48

Controls neck muscles

Medial VST

49

excites axial extensor ms (antigravity)

Lateral VST

50

Input to reticular nuclei is the

cortex

51

Medullary and Lateral RST is:

bilateral and INHIBITS LMNS to inhibit extensor msl contraction

52

what has bilateral innervation to inhibiti LMNS to prevent extensor msl contraction

Medullary and Lateral reticulospinal Tract (both reticulospinal tract)

53

Reticulospinal tracts are composed of scattered groups of neuron cell bodies and fibers that extend throughout the:

brainstem

54

REticulospinal tract input to reticular nuclei is

cortex

55

Reticulospinal tract from Medullary/lateral RST is:

bilaterall and inhibits LMNs to inhibit msl contration

56

Reticulospinal tract from Pontine/ medial RST:

ipsliateral and Excites LMNS--> stimulates extensor msl contraction

57

Why do we see symptoms we do on Decerebrate rigidity

midbrain transsection removes excitatory coritcal input to the INHIBITORY LRST which ascending input to MRST is intact
the faciliaroy influce of MRST is unopposed by inhibitor influence of LRST so we see extensor motor neurons.