L12 - The Cerebellum

Question 1

List the deep cerebellar nuclei

Answer 1

nucleus Fastigii
Nucleus globous
Nucleus emboliformis
Nucleus dentatus

Question 2

What Are the two input pathways for the cerebellar hemispheres?

Answer 2

Mossy fibres

Climbing fibres

Question 3

What type of spike does a climbing fibre produce!

Answer 3

Complex spike

Question 4

What type of spike does a mossy fibre produce?

Answer 4

Simple spik

Question 5

Outline the experiment regarding cerebellu, physiology in monkeys

Answer 5

Tested active and passive movements in monkeys.
Action - moving hand
Could also be done passively using a dc motor
Found that passive hand movements led to changes in complex spike activity and simple spike changes
Active movements has simple spike frequency changw stronger than the complex spike

Question 6

What makes up the vestibulo cerebellum?

Answer 6

Vernis and l. Flocculus nodularis

Question 7

What is the input into the vestibulo-cerebellum?

Answer 7

Visual and vestibular signals

Question 8

What is the output into the vestibular system?

Answer 8

Occulomotor system, head and neck muscles and balance

Question 9

What is the input into the ponto-cerebellum?

Answer 9

Nuclei of the pons

Question 10

What is the output of the ponto cerebellum?

Answer 10

Cortex

Question 11

What is the input to the spino-cerebellum?

Answer 11

Proprioceptive and tactile signals

Question 12

What is the output of the spino-cerebellum?

Answer 12

Muscles of the extremities

Question 13

What are the 5 descending projections of the cerebellum?

Answer 13

Vestibulospinal, reticulospinal

Rubrospinal, tectospinal and corticospinal

Question 14

Outline how LTD works in the cerebellum

Answer 14

When both the parallel and climbing fibres fire simultaneously this leads to activation of both mGluR (Gq) and VGCC which cause an influx of calcium. This leads to AMPAr internalization.

Question 15

What are the consequences of LTD in the cerebellum?

Answer 15

Decrease in the parallel synapse activation
Decrease in purkinje activation
Disinhibition of DCN
Facilitation towards the output nuclei therefore activates motor nuclei

Question 16

Outlone the dart experiment for cerebellAr function

Answer 16

A WT patient throws balls at a board and will adjust to be able to hit the board. Then they wear prism glasses which bends everything to the left. They then adjust to this. When they remove the glasses they are throwing too far to the left therefore adjust to hit the target.

In cerebellar patient no adjustment occurs. So they can never hit the target when wearing the glasses.

Question 17

Outline the VOR experiment for the cerebellum

Answer 17

Place thumb in front of head and move head – see VOR
Now move whole body – no VOR it is suppressed
In cerebellar patients they are unable to suppress the VOR therefore have pathological nystagmus

Question 18

Outline the eye blink reflex experiment.

Answer 18

Airpuff after tone to rabbits
Control subject began to anticipate puff
Cerebellar subject didnt adapt
Cathodal mutation inhibits adaptation
Anodal mutation increases adaptation

Question 19

Outline the postural reflex experiment

Answer 19

Shift floor beneath the patient
The affected side never anticipated
The unaffected side anticipates

Question 20

Outline the flexor reflex experiment

Answer 20

Control patients adjust

Cbl-8 patients do no anticipate

Question 21

Outlone the raspberry task

Answer 21

Pull locked rod from it’s initial grip position with a 3 finger precision grip. It is UUR.
CS - 1kHz tone 450ms prior to UUR
Shows fastest association known
The associate takes longer/ never in cerebral patients

Question 22

What is the only output pathway of the cerebellum?

Answer 22

The deep cerebellar nuclei