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aNeuro Exam 3- Lindsey's > Cerebellum > Flashcards

Flashcards in Cerebellum Deck (72):
1

What is the function of the cerebrocerebellum?

it modulates cortices involved in movement

2

The spinocerebellum contains the _____.

vermis and paravermis

3

What is the function of the paravermal zone?

stretch and withdrawl reflexes

4

Name the 4 deep cerebellar nuclei.

  1. Dentate nucleu
  2. Globose
  3. and emboliform which together make the interposed nucleus
  4. Fastigial Nuclei

5

Small lesions of the cerebellum have _____ effects.

little

6

What is the function of the interposed nucleus?

it fine tunes movements of the limbs

7

Lateral cerebellar lesions impair _____.

the ipsilateral limb

8

What are the 3 layers of the cerebellar cortex?

  1. molecular layer -->
  2. Purkinje layer -->
  3. internal granular layer --> (white matter --> deep cerebellar nuclei)

9

Name the 3 deep cerebellar nuclei (principal outputs from the cerebellum).

  1. dentate nucleus (most lateral)
  2. interposed nucleus
  3. fastigial nucleus (most medial)

10

This zone of the cerebellum modulates cortices involved in movement.

the cerebrocerebellum

11

Name the cerebellar functional zone: vestibular nuclei

the vestibulocerebellum pathway

12

Parallel fibers from granule cells converge on _____.

Purkinje cells

13

The granule cells relay the mossy fiber info thru the _____ to the _____.

parallel fibers --> Purkinje cells

14

What is the function of the dentate nucleus?

planning, initiation and coordination of voluntary movements

15

What is the function of the fastigial nucleus?

control of axial musculature, posture, balance and integration of head and eye movements

16

What are the 3 lobes of the cerebellum?

  1. the floculonodular lobe
  2. the anterior lobe
  3. the posterior lobe

17

What is the output of the cerebrocerebellum pathway?

the contralateral VA/VL thalamus (and red nucleus)

18

This zone of the cerebellum has control of axial skeleton and vestibular control (balance, eye movements).

the vestibulocerebellum

19

Inhibitory interneurons connecting the neighboring Purkinje cells facilitates _____.

lateral inhibition

20

What is the output of the spinocerebellum vermis pathway?

fastigial nucleus --> medial decending tracts

21

How many parallel fibers contact an individual Purkinje cell?

TONS!

22

_____ cerebellar lesions impair the ipsilateral limb.

Lateral

23

What is the Purkinje cell response to excitation by a granule cell?

a simple spike

24

Climbing fibers have a _____ excitation than the mossy fibers, and the Purkinje cells respond with a ______.

stronger --> complex spike

25

Name the cerebellar functional zone: fastigial nucleus --> medial decending tracts

spinocerebellum vermis pathway

26

Name the cerebellar functional zone: the lateral decending tracts and RED NUCLEUS

the spinocerebellum paravermis pathway

27

What is the function of the flocculonodular lobe?

  • axial control and balance
  • eye movement
  • the vestibuloocular reflex
  • vestibule-colic reflex
  • vestibule-spinal reflex

28

What are the inputs to the cerebellum?

  • contralateral cortex --> middle cerebellar peduncle --> cerebellum
  • ipsilateral proprioceptive info from spinal cord --> inferior cerebellar peduncle --> mossy fibers --> cerebellum as a copy of the reflex input
  • contralateral proprioceptive info from spinal cord --> inferior olivary nucleus (ION) --> climbing fibers --> cerebellum as an error signal of unexpected response

29

Cerebellar defects are ALWAYS _____.

ipsilateral (they're either uncrossed or cross twice)

30

Climbing fibers innervate which functional zones of the cerebellum?

all 3: the vestibule, spino, and cerebrocerebellum

31

_____ from granule cells converge on Purkinje cells.

Parallel fibers

32

Midline cerebellar lesions impair _____.

coordination of stance, gait, posture, and equilibrium

33

Climbing fibers ascending in the _______.

inferior cerebellar peduncle

34

What are the 3 phylogenetic divisions of the cerebellum?

  1. the archicerebellum
  2. the paleocerebellum
  3. the neocerebellum

35

Where do parallel fibers come from?

internal granular cells

36

_____ cerebellar lesions impair coordination of stance, gait, posture, and equilibrium.

Midline (vermis)

37

What is the output of the spinocerebellum paravermis pathway?

the lateral decending tracts and RED NUCLEUS

38

In all zones, the climbing fiber input comes from the ____.

contralateral inferior olivary nucleus (ION)

39

Mossy fibers from varying sources excite _____.

granular cells

40

What happens when a simple spike and a complex spike occur in the same location?

an excitation occurring in an already depolarized cell --> fire together = wire together --> long term depression --> reduce the efficiency of this synapse bc this is INHIBITORY

41

The lateral pathways control _____ while the medial pathways are for ____.

lateral = extremities; medial = postural and balance control

42

What is the function of the vermal region?

  • axial control
  • posture
  • locomotion
  • gaze reflexes

43

What does the cerebrocerebellum pathway project to?

the VL (ventrolateral) nucleus of the thalamus

44

What is the output of the vestibulocerebellum pathway?

vestibular nuclei

45

This zone of the cerebellum has control of modulation of stretch and withdrawl reflexes.

the paravermis

46

The mossy fibers come into the cerebellum and innervate the ____.

granule cells

47

What cells in the cerebellar cortex are inhibitory?

  • the Purkinje cells
  • the inhibitory interneurons

48

What are the 3 problems with synergy?

3 Ds (ataxia):

  1. dysmetria
  2. decomposition of movement
  3. dysdiadochokinesia

49

Parallel fibers from ______ converge on Purkinje cells.

granule cells

50

This zone of the cerebellum has control of the axial skeleton, posture, locomotion, and gaze reflexes.

the vermis

51

Climbing fibers come from the _____.

contralateral inferior olivary nucleus (ION)

52

Name the cerebellar functional zone: the contralateral VA/VL thalamus (and red nucleus)

cerebrocerebellum pathway

53

Cerebellar lesions DO NOT produce _____ or _____ loss.

weakness or sensory loss

54

What is the function of the vermis?

  • axial control
  • posture
  • locomotion
  • gaze reflexes

55

Climbing fibers from the ION converge on the ____ cells.

Purkinje

56

What is the function of the vestibulocerebellum?

  • axial control
  • vestibular control (balance, eye movements)

57

____ from varying sources excite granular cells.

Mossy fibers

58

Climbing fibers are oriented _____ to the plane of the dendritic arbor.

perpendicular

59

What is the HANDS tremor?

Hypotonia

Ataxia (3 Ds)

Nystagmus

Dysarthria

Stance and Gait

(Intention) tremor

60

What directly innervates the Purkinje cells?

the climbing fibers

61

The vermis purkinjes --> ______ --> ICP --> medullary reticular formation --> vestibulospinal pathways --> axial motor control

fastigial nucleus

62

What is the function of the paravermis?

modulation of stretch and withdrawl reflexes

63

Where do the mossy fibers come from in the cerebrocerebellum?

the pons

64

Climbing fibers from the ____ converge on Purkinje cells.

inferior olivary nucleus (ION)

65

What facilitates lateral inhibition?

inhibitory interneurons connecting the neighboring Purkinje cells

66

____ from the ION converge on the Purkinje cells.

Climbing fibers

67

The cerebrocerebellum is the most _____ part of the cerebellum anatomy.

lateral

68

What are the 2 types of fibers that are the major input tracts to the cerebellum?

climbing fibers and mossy fibers

69

The vestibulocerebellum contains the _____.

floculonodular lobe

70

What are the 3 gross divisions of the cerebellum?

2 hemispheres + 1 midline vermis

71

Where do the mossy fibers come from in the vestibulocerebellum?

the vestibular system

72

Where do the mossy fibers come from in the spinocerebellum?

the spine and elsewhere