The Cerebellum

Question 1

where in the brain is the cerebellum?

Answer 1

an outgrowth of the rostral hindbrain

Question 2

where does the cerebellum specifically arise from?

Answer 2

just caudal to midbrain:
isthmus and rhombomere 1

Question 3

when does the cerebellum grow rapidly?

Answer 3

in the postnatal period

Question 4

the developing cerebellum is small when?

Answer 4

at birth

Question 5

what is the cerebellum central white matter shaped like?

Answer 5

the trunk of a tree

Question 6

what do the white matter branches of the cerebellum form?

Answer 6

major lobules of the central cerebellum

Question 7

in what type of section does the cerebellum look like a piece of cauliflower?

Answer 7

mid-sagittal section

Question 8

what is the midline of the CB?

Answer 8

the vermis

Question 9

what does the vermis consist of?

Answer 9

10 recognizable lobules in all mammals

Question 10

the cerebral cortex relies on the CB for what?

Answer 10

movement coordination

Question 11

the CC requests CB info via what?

Answer 11

the corticopontine pathway

Question 12

where does the corticopontine tract travel to?

Answer 12

the rostral hindbrain

Question 13

the pontine nuclei send axons to the CB of what side?

Answer 13

the opposite side

Question 14

pontine nuclei send axons to CB via what?

Answer 14

the middle cerebellar peduncle

Question 15

the CB responds to forebrain requests via what?

Answer 15

the superior cerebellar peduncle

Question 16

where does the superior cerebellar peduncle travel to?

Answer 16

the opposite ventrolateral thalamic nucleus

Question 17

the superior cerebellar peduncle travels to the ventrolateral thalamic nucleus of which side?

Answer 17

the opposite side

Question 18

what carries SC and BS fibers on it’s way to the CB cortex.

Answer 18

the inferior cerebellar peduncle

Question 19

what is the CB vermis of all mammals divided into?

Answer 19

10 lobules

Question 20

what are the 10 lobules of the CB vermis divided by?

Answer 20

a series of deep fissures

Question 21

what is the largest fissure in the CB vermis?

Answer 21

the primary fissure

Question 22

what does the primary fissure divide?

Answer 22

the anterior vermis from the posterior vermis

Question 23

what does the anterior vermis consist of?

Answer 23

lobules 1 - 5

Question 24

what does the posterior vermis consist of?

Answer 24

lobules 6 - 10

Question 25

what is the name of lobule 10?

Answer 25

the nodule

Question 26

the human CB hemisphere is marked by 100s of what?

Answer 26

folia

Question 27

what direction do folia run?

Answer 27

medial to lateral

Question 28

what is the center of the CB filled with?

Answer 28

the deep CB white matter

Question 29

what is in the deep CB white matter?

Answer 29

3 deep CB nuclei on either side

Question 30

what is the largest deep CB nuclei?

Answer 30

the dentate nucleus

Question 31

where is the dentate nucleus placed?

Answer 31

laterally

Question 32

the CB is connected to the hindbrain via:

Answer 32

3 CB peduncles on either side

Question 33

what does inferior CB peduncle contain?

Answer 33

fibers entering CB from SC and inferior olive

Question 34

what does middle CB peduncle contain?

Answer 34

fibers entering CB from basilar pons

Question 35

what does the superior CB peduncle contain?

Answer 35

fibers that leave CB to travel through the red nucleus to reach the thalamus

Question 36

each cerebral cortex is connected to sensory and motor activities on what side of the body?

Answer 36

the opposite side

Question 37

each CB side is connected to which body side?

Answer 37

the ipsilateral/same side

Question 38

when one CB hemisphere is damaged, what are the classic symptoms?

Answer 38

incoordination of voluntary movement and tremor on the ipsilateral side.

Question 39

how many CB cortex layers are there?

Answer 39

3

Question 40

what are the CB cortex layers?

Answer 40

outer molecular layer the Purkinje cell layer the inner granule cell layer

Question 41

what is in the deep to the granule cell layer?

Answer 41

the deep CB white matter

Question 42

what parts of the CB cortex are uniform?

Answer 42

the layers the relative thickness of each layer

Question 43

what is in the deep to the CB cortex?

Answer 43

the deep CB white matter

Question 44

what are the output cells of the CB cortex?

Answer 44

the Purkinje cells

Question 45

where do the axons of the Purkinje cells project to?

Answer 45

to the CB nuclei

Question 46

most fibers projecting to the CB cortex are:

Answer 46

mossy fibers

Question 47

what do mossy fibers that project to the CB cortex synapse with?

Answer 47

granule cells

Question 48

what exceptions do not have mossy fibers that project to the cerebral cortex?

Answer 48

inferior olive input

Question 49

where does inferior olive input directly go to in the CB?

Answer 49

dendritic trees of Purkinje cells

Question 50

inferior olive inputs go to the dendritic trees of Purkinje cells in the form of:

Answer 50

climbing fibers

Question 51

where do mossy fibers arise from?

Answer 51

the pontine nuclei cells & other large pre-cerebellar nuclei in the hindbrain and from the SC.

Question 52

granule cells send their axons to:

Answer 52

the dendritic spines of Purkinje cells

Question 53

granule cells comprise what percentage of neurons in the brain?

Answer 53

70%

Question 54

granule cells are tiny and tightly packed; their density in the cerebellum is:

Answer 54

1 million per cubic millimeter

Question 55

there is evidence that inferior olivary cells control what in the CB?

Answer 55

the time code of the CB

Question 56

what does the time code that the inferior olivary cells send to the CB ensure?

Answer 56

that learned movement is played back in the right timing sequence

Question 57

at what rate do inferior olivary cells fire the time code to the CB?

Answer 57

10Hz (10 APs per second)

Question 58

rat microelectrode recordings suggest that every folium in the CB codes a different:

Answer 58

movement sequence

Question 59

what are movement sequence examples the folium in the CB could encode?

Answer 59

taking food with the fingers and transferring it to the mouth running behaviour

Question 60

given that there are 10,000s of folium in the CB, it is possible that the CB:

Answer 60

keeps learning new movement sequences in adult life

Question 61

the largest human CB connection is with what?

Answer 61

the motor cortex

Question 62

what is the journey of the corticopontine pathway?

Answer 62

arises from the CC synapses in the pons enters the CB as the middle CB peduncle

Question 63

the middle CB peduncle is a way for the motor cortex to:

Answer 63

ask the CB for help when complex movement is required

Question 64

the answer regarding complex movements is returned to the motor cortex via:

Answer 64

the superior CB peduncle

Question 65

where do the fibers of the superior CB peduncle synapse?

Answer 65

in the ventrolateral nucleus of the thalamus

Question 66

thalamocortical fibers travel to where?

Answer 66

the motor cortex

Question 67

the ratio of the number of CB cells to the number of CC cells in the human brain is:

Answer 67

4:1 respectively

Question 68

what is the main way that the CB tracks limb movement?

Answer 68

through sensation from the skin

Question 69

it appears that most input in the CB for tracking movement comes from:

Answer 69

receptors that detect sensations of stretching, contact and/or folding in the skin

Question 70

what do the skin sensations inputted to the CB provide fine detail on?

Answer 70

movement of the limbs and other body parts