Slpa 853 - Neurology - Cerebellum

Front 1

The cerebellum monitors signals from where? Resulting in what?

Back 1

-from the cortex
-resulting in movements in the periphery

Front 2

What does the cerebellum compare? AND where does it send corrective signals?

Back 2

-intended and actual movements
-send corrective signals to cortex

Front 3

What can damage to the cerebellum cause?

Back 3

profound disturbances of movement (i.e., ataxia of limbs, ataxia of speech movements)

Front 4

What structure connects the 2 hemispheres of the cerebellum (like the corpus callosum)?

Back 4

vermis

Front 5

The cerebellum consists of 2 hemispheres including what 3 basic structures?

Back 5

-gray and white matter (arbor vitae)
-intra-cellular nuclei (deep nuclei)
-cerebellar peduncles

Front 6

What runs horizontally in the cerebellar cortex?

Back 6

folia (folium - fold) - smaller than the folds in the cerebral cortex

Front 7

About how many neurons does the gray matter of the cerebellar cortex contain? AND cerebral cortex?

Back 7

-cerebellar - 50 billion
-cerebral - 22 billion

Front 8

True or false: The 2 hemispheres of the cerebellum affect movements on opposite sides of the body.

Back 8

False: same side of the body - ipsilateral (left side lesion -> left side affected)

Front 9

What are the 3 masses of gray matter (deep nuclei) in the cerebellum?

Back 9

-dentate nucleus (largest)
-interpositus nucleus (emboliform and globose nucleus)
-fastigial nucleus

Front 10

What function do the peduncles serve in the cerebellum?

Back 10

the "information highways" of the cerebellum

Front 11

What are the 3 peduncles of the cerebellum? AND what do they connect the cerebellum to?

Back 11

-superior cerebellar peduncle (cerebellum to midbrain)
-middle cerebellar peduncle (cerebellum to pons)
-inferior cerebellar peduncle (cerebellum to medulla oblongata)

Front 12

From which cerebellar peduncle(s) do(es) all information leave?

Back 12

superior cerebellar peduncle

Front 13

From which cerebellar peduncle(s) do(es) all information come in thru?

Back 13

-middle cerebellar peduncle
-inferior cerebellar peduncle

Front 14

What are the horizontal divisions of the cerebellum?

Back 14

-anterior lobe
-posterior lobe
-flocculonodular lobe

Front 15

What are the vertical divisions of the cerebellum?

Back 15

-vermis
-intermediate cerebellum
-lateral cerebellum

Front 16

What are the functional subdivisions of the cerebellum? AND where are they located?

Back 16

-spinocerebellum (vermis + intermediate parts of cerebellar hemispheres)
-cerebrocerebellum (lateral zone of the cerebellar hemispheres)
-vestibulocerebellum (flocculonodular lobe)

Front 17

What type of input does the spinocerebellum receive?

Back 17

-visual and auditory
-spinal and trigeminal input (sensory info from trunk and proximal portion of limbs)

Front 18

What nucleus does the spinocerebellum give output to?

Back 18

fastigial nucleus

Front 19

What is the spinocerebellar responsible for?

Back 19

-the coordination of rapid motor activity (--intended movements of cortex are compared with the actual performance in the periphery [muscle --corrects any "errors" by making adjustments)
-regulation of muscle tone, coordination of skilled voluntary movement
-feed forward mechanism

Front 20

What is the feed forward mechanism?

Back 20

anticipates and adjusts movements

Front 21

Where does the spinocerebellum-intermediate zone project to?

Back 21

to the interposed nuclei (sensory info), then to the red nucleus in midbrain (involved in motor coordination), then to the ventrolateral thalamic nucleus in the diencephalon

Front 22

What input does the lateral zone of the cerebrocerebellum receive?

Back 22

-receives info about intended movements from the cerebral cortex via the pontine nucleus (nucleus in pons)
-receives somatosensory info (position and rate of movements)
-computes the contribution that various muscles will have to make to perform the intended movement

Front 23

Where is output of the lateral zone of the cerebrocerebellum sent?

Back 23

-computations are sent to the dentate nucleus (deep cerebellar nucleus)
-dentate nucleus sends info to the vetrolateral thalamus, which projects to the cortex

Front 24

What does the cerebrocerebellum consist of?

Back 24

the lateral zone of each hemisphere

Front 25

Where does the cerebrocerebellum receive input from?

Back 25

corticopontine input

Front 26

What is the cerebrocerebellum involved in?

Back 26

-timing and precision of movements
-planning and initiation of voluntary activity
-control of independent limb movements, especially rapid, skilled movements

Front 27

Where is the flocculonodular lobe located?

Back 27

at the caudal end of the cerebellum

Front 28

Where does the flocculonodular lobe receive input from?

Back 28

from the corticopontine and vestibular system

Front 29

Where does the flocculonodular lobe of the vestibulocerebellum project axons to?

Back 29

to the vestibular nucleus

Front 30

What is the function of the flocculonodular lobe of the vestibulocerebellum?

Back 30

postural reflex, balance, eye movement

Front 31

What does the vestibulocerebellum consist of?

Back 31

flocculonodular lobe

Front 32

What are the 3 distinct layers of neurons of the cerebellum?

Back 32

-molecular layer
-purkinje layer
-granular layer

Front 33

Describe the molecular layer of the cerebellum.

Back 33

-multiple layers
-outer stellate and basket cell bodies (inhibitory)

Front 34

Describe the purkinje layer of the cerebellum.

Back 34

-middle layer
-single layer
-purkinje cell bodies (inhibitory)

Front 35

Describe the granular layer of the cerebellum.

Back 35

-multiple layers
-inner layer
-granule and golgi cell bodies (inner stellate)

Front 36

What are the 2 types of fibers that make up the afferent pathways of the cerebellum?

Back 36

-mossy fibers
-climbing fibers

Front 37

Where do the afferent pathways enter the cerebellum via?

Back 37

the inferior and middle cerebellar peduncle

Front 38

Describe the mossy fibers afferent pathway to the cerebellum.

Back 38

-excitatory input to the cerebellum (to the purkinje cells)
-enter the granule cell layer and synapse on the dendrites of granule cells
-granule cells then send their axons up to the molecule layer, where they end in a T and run parallel to the surface (called parallel fibers)
-parallel fibers synapse on the huge dendritic arrays of the purkinje cells

Front 39

What are the 2 mossy fiber pathways?

Back 39

-vestibulocerebellar pathways (flocculonodular lobe)
-spinocerebellar pathways (vermis)

Front 40

Where does the final output for the cerebellum come from?

Back 40

deep nuclei

Front 41

What is the second main type of input?

Back 41

climbing fibers

Front 42

What type of input do the climbing fibers provide to the purkinje cells?

Back 42

excitatory

Front 43

Describe the climbing fibers pathway to the cerebellum.

Back 43

-they go straight to the purkinje cell layer and snake up the purkinje dendrites, like ivy climbing a trellis
-each climbing fiber associates with only one purkinje cell, but when the climbing fiber fires, it provokes a large response in the purkinje cell
-the purkinje cell compares and processes the varying inputs it gets, and finally sends its own axons out thru the white matter and down to the deep nuclei

Front 44

Information that comes into the cerebellum is __________, going out the information is ____________.

Back 44

-into= excitatory
-out= inhibitory

Front 45

What are types of efferent axons?

Back 45

-purkinje cell axons
-inerneurons:
--golgi cell axons (granule cell layer)
--inner and outer stellate and basket cell axons (molecular layer)
--they branch down into the purkinje cell layer

Front 46

What type of information do efferent pathways carry from the cerebellum?

Back 46

all inhibitory

Front 47

What does injury to the midline (vermis region) cerebellar structures typically produce?

Back 47

-postural sway and tremor, and difficulties with locomotion
-movements are characteristic of those of a drunk

Front 48

What does injury of later (lateral zone of hemispheres) structures typically produce?

Back 48

-loss of coordination of the limbs-Dyssynergia, often with large amplitude and low-frequency tremor
-inaccuracy in range and direction of movement-Dysmetria
-Dysdiadochokinsia

Front 49

What is dyssynergia?

Back 49

loss of coordination of the limbs

Front 50

What is dysmetria?

Back 50

inaccuracy in range and direction of movement

Front 51

What is dysdiadochokinesia?

Back 51

an irregular pattern of alternating movements