Control of Movement 3

Question 1

What are the three layers if the cerebellum?

Answer 1

Molecular Layer
Purkinje cell layer
Granule cell layer

Question 2

What is the function of granule cells in the cerebellum?

Answer 2

Make interconnections, can act as transporters and integrators of information from the granular layer up to the molecular layer

Question 3

What is the function of stellate cells?

Answer 3

Small cells, distributing information on a more ‘local’ level

Question 4

What is the function of parallel fibres (from granule cell)?

Answer 4

Move information throughout layers in a linear fashion (between Purkinje cells)

Question 5

What is the function of basket cells?

Answer 5

Form a basket like structure around Purkinje cells

Question 6

What is the function of mossy fibres?

Answer 6

Input
One of the main sensory inputs
Terminate in the granule later where they spread around their information to other cells

Question 7

What is the function of the climbing fibres?

Answer 7

Input specifically from olives
Come from the olives and ‘climb up to’ the molecular later where they wrap themselves around the dendrites
Important in learning about movements for improvement on correction of motor output

Question 8

What inputs arrive at the vestibular system?

Answer 8

• Inputs from vestibular nuclei (balance) project to the vestibulocerebellum (flocculonodular lobe) and vermis
• The flocculonodular is involved with maintaining balance and posture

Question 9

What inputs arrive for proprioceptive feedback?

Answer 9

• Inputs from ascending sensory spinal pathways derived principally from proprioceptors to the spinocerebellum (= Anterior lobe + Vermis + Intermediate vermis)
• The spinocerebellum modulates axial or antigravity muscles and eye movement
• The spinocerebellum contains a somatotopical map of the body

Question 10

What inputs arrive for cortical input?

Answer 10

• Inputs from the motor and pre-motor cortex as well as somatosensory cortex via multiple pontine nuclei project to the cerebrocerebellum
• The cerebrocerebellum is involved with motor planning, and feeds information back towards the cerebra
• Functions to sequence and coordinate distal muscles esp. during locomotion or juggling etc.

Question 11

What is the flocculonodular involved in?

Answer 11

Involved with maintaining balance and posture

Question 12

What is the spinocerebellum involved in?

Answer 12

Modulates axial or antigravity muscles and eye movement

Contains a somatotopical map of the body

Question 13

What is the cerebrocerebellum involved in?

Answer 13

Involved in motor planning, and feeds information back towards the cerebra.
Functions to sequence and coordinate distal muscles

Question 14

Name the deep nuclei of the cerebellum from lateral to medial.

Answer 14

Dentate nucleus
Emboliform nucleus
Globose nucleus
Fastigial nucleus

Question 15

What are the outputs of the fastigial nuclei?

Answer 15

• Medial descending systems (trunk and proximal via reticular formation)
• Vestibular nuclei, tectum and cranial nerve nuclei

Question 16

What nuclei are involved in motor execution?

Answer 16

Fastigal nuclei

Interposed nuclei

Question 17

What is the output of the interposed nuclei?

Answer 17

• Lateral descending systems (distal and extremities via spindles)

Question 18

What is the output of the dentate nuclei?

Answer 18

• Motor and premotor cortices

Question 19

What nuclei are involved in motor planning?

Answer 19

Dentate nuclei

Question 20

What nuclei are involved in head and eye movements?

Answer 20

vestibular, Tetum and cranial nerve nuclei

Question 21

What is flocculonodular lobe syndrome?

Answer 21

Not common
Seen in children with medulloblastoma
Characterised by truncal ataxia, wide based stance and swaying.

Question 22

In general terms, what do medial cerebellar lesions affect?

Answer 22

Medial descending pathways, causing unsteady gait (truncal ataxia), problems with balance, posture and eye movement abnormalities (nystagmus)

Question 23

What do lateral cerebellar lesions affect?

Answer 23

Affect control of distal muscles and motor planning.

Results in limb ataxias.

Question 24

What do lesions of the cerebrocerebellum cause?

Answer 24

• Delay in initiation of movement

- Decomposition of multi-joint movements (e.g. loss of complex motor skills)

Question 25

What do lesions of the intermediate lobe (spinocerebellum) cause?

Answer 25

Affect distal muscles and cause limb ataxia and action tremor

Question 26

What do lesions of the vermis (spinocerebellun) OR fastigial nucleus cause?

Answer 26

Affect axial and trunk muscles

Makes balance unsteady (wide stance)

Question 27

Where is information from the vestibular nuclei passed to?

Answer 27

The Flocculonodular lobe or vestibulocerebellum and the vernal/paravermal areas

Question 28

What does olivary information enable?

Answer 28

The calculation of predicted posture in advance of it happening so feed forward posture adjustments allows fast postural changes

Question 29

What are the pre and primary motor cortex and somatosensory cortex via?

Answer 29

Pontine nuclei and middle peduncle

Question 30

Describe the process of sequencing and timing complex movements.

Answer 30

• Pre motor and sensory areas in the cortex begin to plan for a complex movement
• The plan is transferred to the lateral lobes of the cerebellum (cerebrocerebellum) via pontine nuclei
• Output concerning the order and timing of the movements is routed through the dentate nucleus and back via the thalamus to the cortex

Question 31

Describe anterior lobe syndrome.

Answer 31

Planned and actual motor output are compared and corrective signals sent via the thalamus. Errors in corrective signals from cerebellum. 
Includes overshoot (dysmetria), intention tremor and lack of movement dampening