Cerebellum

Question 1

What is the function of the cerebellum? (2)

Answer 1

1. production of co-ordinated movements.

2. maintains balance and posture

Question 2

How does the cerebellum produce coordinated movements?

Answer 2

coordinates -:

1. time
2. force
3. duration

this is SYNERGY

Question 3

What is seen on a dorsal view of the cerebellum? (5)

Answer 3

1. anterior lobe
2. primary fissure
3. posterior lobe
4. hemisphere
5. vermis

Question 4

What is seen on a ventral view of the cerebellum?

Answer 4

1. tonsil

Question 5

What can be seen from the view form the IV ventricle? (6)

Answer 5

1. flocullus
2. nodule
3. tonsil
4. inferior cerebellar peduncle
5. middle cerebellar peduncle
6. superior cerebellar peduncle

Question 6

What are the 3 function subdivisions of the cerebellum?

Answer 6

1. archicerebellum or vestibulocerebellum
2. paleocerebellum or spinocerebellum
3. neocerebellum or cerebrocerebellum

Question 7

What does the archicerebellum/vestibulocerebellum comprise of?

Answer 7

flocculonodular lobe and part of the vermis

Question 8

What does the paleocerebellum or spinocerebellum comprise of?

Answer 8

most of the vermis and adjacent region of hemispheres.

Question 9

What does the neocerebellum/cerebrocerebellum comprise of?

Answer 9

lateral parts of the hemispheres

Question 10

What is the function of the vestibulocerebellum?

Answer 10

• coordinates muscles involved in maintaining balance and constancy of visual fields.
• receives input from vestibular apparatus of inner ear

Question 11

What is the function of spinocerebellum?

Answer 11

co-ordinates muscles involved in posture and locomotion

Question 12

What is the function of the cerebocerebellum?

Answer 12

co-ordinates movements of distal limbs - particularly fine and skilled movements of the hands.

Question 13

What is rubber necking?

Answer 13

keeping gaze constant despite moving your head, neck and body.

Question 14

What muscles are involved in moving the eye ball side to side?

Answer 14

• lateral rectus

- medial rectus

Question 15

What is involved in balance?

Answer 15

lateral semi-circular canal

Question 16

What type of pathway is the vestibulospinal pathway and what does it control?

Answer 16

descending pathway

controls posture

Question 17

Is the influence of the cerebellum ipsilateral or contralateral?

Answer 17

ipsilateral

Question 18

What does the spinocerebellar tract connect?

Answer 18

proprioception and other sensory information from spinal cord passes into the cerebellum via the ICP.

ON SAME SIDE

Question 19

In terms of the cerebellocerebellar connections where does it receive input from motor cortex?

Answer 19

via Pontine nuclei and inferior olivary nucleus

Question 20

In terms of the cerebellar connections where does the output go to?

Answer 20

1. motor cortex - via the thalamus
2. reticular nuceli
3. red nucleus

• ensures intended movements are controlled and coordinated

Question 21

In terms of the cerebella connections where does input come from?

Answer 21

cortex - including motor cortex via nuclei in Pons and via inferior olivary nucleus.

Question 22

Where do all descending pathways descend to?

Answer 22

from superior colliculus to LMNs

Question 23

What is the cerebrocerebellum also involved in?

Answer 23

blink response

• puff of air at cornea = blink
• a sound made before blink
• the sound alone will induce blink

Question 24

What may stop the blink response?

Answer 24

damage to the inferior olivary nucleus

• puff of air = no blink
• sound = no blink

Question 25

What are the effects of cerebellar damage?

Answer 25

- in-coordination/ ataxia (no order) | - disordered movement

Question 26

What happens in truncal ataxia?

Answer 26

- inability to stand or sit without falling over

Question 27

Where is the lesion in truncal ataxia and what does it affect and what is it most commonly due to?

Answer 27

midline lesion affects vetsibulocerebellum due to medulloblastoma

Question 28

What happens in gait ataxia?

Answer 28

lower limbs mostly affected producing staggering and wide-based gait.

Question 29

Where is the lesion in gait ataxia and who is it most common in?

Answer 29

lesion of the spinocerebellum chronic alcoholics- due to degeneration of cerebellar neurons in paravermal areas

Question 30

What are signs of a lesion of the cerebellar hemisphere? (6)

Answer 30

1. inncoordination of voluntary movement - Upper limbs 2. tremor of intent 3. past pointing or dysmetria 4. adiadochokinesia 5. dysarthria 6. nystagmus

Question 31

What are common lesions of the cerebellum? (3)

Answer 31

1. midline lesions - truncal ataxia 2. anterior lobe lesions - gait ataxia 3. Neocerebllar lesions - incoordination of voluntary movements