Cerebellum

Question 1

State the 3 lobes of the cerebellum.

Answer 1

Anterior
Posterior
Flocculonodular

Question 2

The cerebellum is divided sagitally into 3 zones. What are these zones?

Answer 2

Vermis (midline)
Intermediate hemisphere (closest to vermis)
Lateral hemisphere

Question 3

State the 3 layers of the cerebellar cortex.

Answer 3

Molecular layer
Piriform layer (Purkinje cells)
Granular layer (Granule cells)

Question 4

Name the 3 deep nuclei that are involved in the connections of the cerebellum with other parts of the body. Include their function.

Answer 4

Fastigial = involved in control of balance and connected with vestibular nuclei
Interposed + Dentate = both involved in voluntary movement and are connected to the thalamus and the red nucleus

Question 5

What are the 3 sources of input into the cerebellum and what do they connect with?

Answer 5

Mossy Fibres – from the cortex and pons (corticopontine fibres)
Mossy Fibres – from the spinocerebellar tract
Climbing Fibres – from the inferior olive

Question 6

Functionally, the cerebellum can be divided in three. What are these three divisions?

Answer 6

Vestibulocerbellum
Spinocerebellum
Cerebrocerebellum

Question 7

What is the role of the vestibulocerebellum?

Answer 7

Vestibulocerbellum is the flocculonodular lobe It is connected to vestibular nuclei Involved in balance, posture and regulation of gait It is also involved in coordination of head movements with eye movements

Question 8

Which parts of the cerebellum are part of the spinocerebellum?

Answer 8

Vermis and intermediate hemisphere

Question 9

From where does the spinocerebellum receive inputs?

Answer 9

Afferents from axial portions of the body, visual, auditory and trigeminal inputs –> vermis Afferents from limbs –> intermediate hemisphere

Question 10

What are the roles of the spinocerebellum?

Answer 10

Coordination of speech
Adjustment of muscle tone
Coordination of limb movement

Question 11

Which part of the cerebellum is part of the cerebrocerebellum?

Answer 11

Lateral hemisphere

Question 12

From where does the cerebrocerebellum receive inputs and what are its main functions?

Answer 12

It receives projections from the cortex

Main functions are: 
Coordination of skilled movements
Cognitive function  
Attention  
Processing of language  
Emotional control

Question 13

In summary, what are the four main functions of the cerebellum?

Answer 13

Maintenance of balance and posture
Coordination of voluntary movements
Motor learning
Cognitive functions

Question 14

State three syndromes caused by dysfunction of different parts of the cerebellum.

Answer 14

Vestibulocerebellar syndrome/Flocculonodular lobe syndrome Spinocerebellar syndrome
Cerberocerebellar syndrome

Question 15

What are the symptoms of vestibulocerebellar syndrome?

Answer 15

This syndrome is similar to vestibular disease
Patients tend to lose their balance
Gait ataxia
Tendency to fall.

Question 16

What behavioural habit is spinocerebellar syndrome associated with?

Answer 16

Chronic alcoholism

Question 17

Describe the symptoms of spinocerebellar syndrome.

Answer 17

Mainly affects the legs It causes abnormal gait and a wide-based stance

Question 18

Describe the symptoms of cerebrocerebellar syndrome.

Answer 18

Damage mainly affects the arms
It affects coordinated movements
Speech becomes very hesitant and slow (staccato)

Question 19

What are the main signs of cerebellar disorders?

Answer 19

Ataxia– general impairments in movement coordination and accuracy
Dysmetria– inappropriate force and distance for target-directed movements Intention tremor– increasingly oscillatory trajectory of a limb in a target directed movement (nose-finger tracking)
Dysdiadochokinesia– inability to perform rapid alternating movements Scanning speech– staccato, due to impaired coordination of speech muscles

Question 20

State a hereditary and acquired cause of classic ‘cerebellar’ symptoms.

Answer 20

Hereditary – Friedreich’s Ataxia

Acquired – Multiple Sclerosis