Chapter 6: The Cerebellum

Question 1

The vermis controls which areas of the body?

Answer 1

the axial and proximal musculature of the limbs

Question 2

In general, the intermediate part of hemisphere of the cerebellum controls which part of the body?

Answer 2

controls distal musculature of the limbs

Question 3

What is the primary function of vermis and intermediate zones of the cerebellum?

Answer 3

ongoing motor execution

Question 4

Where are the major inputs for the vermis and intermediate zones from?

Answer 4

spinal cord

Question 5

What is the function of the (lateral) hemisphere of the cerebellum?

Answer 5

motor planning/ coordination

Question 6

What is the function of the flocculonodular lobe?

Answer 6

balance and eye movements

Question 7

What are the major inputs to the (lateral) hemispheres of the cerebellum?

Answer 7

cerebral cortex and inferior olivary nucleus

Question 8

What are the major inputs to the flocculonodular lobe?

Answer 8

vestibular nuclei

Question 9

Major input to the cerebellum travels in what structure (area of the brain)?

Answer 9

inferior cerebellar peduncle (restiform body) and middle cerebellar peduncle (MCP)

Question 10

Major outflow of the cerebellum travels in what structure?

Answer 10

in the superior cerebellar peduncle (SCP)

Question 11

Mossy fibers of the cerebellum follow what tracts?

Answer 11

• vestibulocerebellar
• spinocerebellar (cortico)
• pontocerebellar

Question 12

What areas of the brain do the mossy fibers enter the cerebellum from?

Answer 12

• vestibulocerebellar > ICP
• spinocerebellar (cortico) > ICP and SCP
• pontocerebellar > MCP (decussate)

Question 13

What is the target and function of mossy fibers?

Answer 13

excitatory termination of granule cells (glutamate)

Question 14

What is the tract that climbing fibers use?

Answer 14

olivocerebellar

Question 15

What is the target of the climbing fibers?

Answer 15

Excitatory terminals on Purkinje cells

Question 16

What are the 3 cell layers of the cortex of the cerebellum?

Answer 16

molecular layer, the Pukinje layers and the granule cell layer

Question 17

Describe the molecular layer of the cortex of the cerebellum? Location? Make up?

Answer 17

the outer layer and

made up of basket and stellate cells as well as parallel fibers which are the axons of the granule cells

Question 18

Describe the Purkinje layer of the cortex of the cerebellum. Location? Function?

Answer 18

the middle and most important layer of the cerebellar cortex

all of the inputs the the cerebellum are directed toward influencing the firing of Purkinje cells, and only axons of Purkinje cells leave the cerebellar cortex

Question 19

Describe the granule cell layer. Where is it located? What does it contain?

Answer 19

innermost layer of cerebellar cortex and contains Golgi cells, granule cells, and glomeruli

Question 20

What is the only excitatory neuron of the cerebellar cortex?

Answer 20

the granule cell

Question 21

Target of the Purkinje cells?

Answer 21

deep cerebellar nuclei

Question 22

What is the transmitter of the purkinje cell?

Answer 22

GABA

Question 23

What is the function of the purkinje cell, inhibitory or excitatory?

Answer 23

inhibitory

Question 24

The granule cell target?

Answer 24

Purkinje cells

Question 25

What is the transmitter of the granule cell?

Answer 25

glutamate

Question 26

What is the function of the granule cell, inhibitory or excitatory?

Answer 26

excitatory

Question 27

What is the target of the stellate cells?

Answer 27

Purkinje cells

Question 28

What is the neurotransmitter for the stellate cell?

Answer 28

GABA

Question 29

Does the stellate cell have excitatory or inhibitory action?

Answer 29

inhibitory

Question 30

Target of the basket cells?

Answer 30

Purkinje cells

Question 31

What is the neurotransmitter of basket cells?

Answer 31

GABA

Question 32

What is the function of basket cells?

Answer 32

inhibitory

Question 33

What is the target of the golgi cells?

Answer 33

granule cells

Question 34

What is the transmitter for Golgi cells?

Answer 34

GABA

Question 35

Are the golgi cells excitatory or inhibitory?

Answer 35

inhibitory

Question 36

What area of the cerebellum contains the deep cerebellar nucei?

Answer 36

white matter

Question 37

Climbing fibers originate exclusively from what area of the brainstem?

Answer 37

inferior olivary complex on nuclei on the contralateral side of medulla

Question 38

What parts of the body do the mossy fibers derive from?

Answer 38

from spinal cord, pontine nuclei, or vestibular nuclei

Question 39

Mossy fibers exert a excitatory or inhibitory effect on granule cells?

Answer 39

excitatory effect

Question 40

The golgi cell inhibits which cells that activate it in the first place?

Answer 40

the granule cell

Question 41

Purkinje cells in the flocculonodular lobe project to which deep cerebellar nucluei?

Answer 41

lateral vestibular nuclei

Question 42

Purkinje cells in the vermis project to which deep cerebellar nuclei?

Answer 42

fastigial nuclei

Question 43

Purkinje cells in the intermediate hemisphere project to which deep cerebellar nuclei?

Answer 43

interposed (globose and emboliform) nuclei

Question 44

Hemisphere lesions lead to what symptoms?

Answer 44

ipsilateral symptoms: intention tremor, dysmetria, dysdiadochokinesia, scanning dysarthria, nystagmus, hypotonia

Question 45

Vermal lesions lead to what symptoms?

Answer 45

truncal ataxia

Question 46

What is the main path the Purkinje cells take to the contralateral cerebral cortex?

Answer 46

Purkinje cells > deep cerebellar nucleus; dentate nucleus > contralateral VL > primary motor cortex

Question 47

Name the major deep cerebellar nuclei from lateral to medial?

Answer 47

dentate nucleus, interpositus nucleus, fastigial nucleus

Question 48

Where is the vestibulocerebellum?

Answer 48

the flocculonodular lobe

Question 49

Where is the spinocerebellum located?

Answer 49

intermediate hemisphere

Question 50

Where is the pontocerebellum located?

Answer 50

lateral hemispheres

Question 51

The vestibulocerebellum sends its efferents where?

Answer 51

vestibular nucleus

Question 52

The spinocerebellum sends efferents where?

Answer 52

* red nucleus * reticular formation

Question 53

What is the function of the spinocerebellum?

Answer 53

* influence LMNs via the reticulospinal and rubrospinal tracts to adjust posture and effect movement

Question 54

Where does the pontocerebellum send efferents?

Answer 54

thalamus (VA, VL) then cortex

Question 55

Function of the vestibulocerebellum?

Answer 55

elicit positional changes of eyes and trunk in response to movement of the head

Question 56

Function of the spinocerebellum?

Answer 56

influence LMNs via the reticulospinal and rubrospinal tracts to adjust posture and effect movement

Question 57

Function of the pontocerebellum?

Answer 57

influence on LMNs via the corticospinal tract, which effect voluntary movements, especially sequence and precision

Question 58

Symptoms of lesions that include the hemispheres. | Describe same symptoms stated earlier, but be clear and more in depth

Answer 58

* intention tremors * dysmetria (past pointing) * dysdiadochokineasia (adiadochokinesia - reduced ability to perform alternating movements * scanning dysarthria asynergy of muscles responsible for speech (staccato speech) * gaze dysfunction: eyes try to fix on point may stop short or go past it; nystagmus may be present, particularly with acute cerebellar damage; fast component usually directed toward the involved cerebellar hemisphere

Question 59

How do vermal lesions present?

Answer 59

difficulaty maintaining posture, gait, or balance (an ataxic gait)

Question 60

What is usually the cause of anterior vermis lesions?

Answer 60

usually result of degeneration from alcohol abuse and are present with gait ataxia

Question 61

What causes posterior vermis lesions?

Answer 61

results from medulloblastomas or ependymomas and present with truncal ataxia.