Cerebellum

Question 1

Name the 3 lobes of the cerebellum

Answer 1

Anterior
Posterior
Floculonodular lobe

Question 2

What is the function of the penduncles in the cerebellum?

Answer 2

they connect the brainstem to the cerebellum

Question 3

Identify where the cerebellum is located within the brain.

Answer 3

Dorsal (behind) the brainstem and below the occipital lobe

Question 4

What is the function of the vermis in the cerebellum?

Answer 4

Divides the 2 cerebral hemispheres (right and left) of the cerebellum.

Question 5

What are the two fissures of the cerebellum?

Answer 5

Primary (separating anterior and posterior lobes)

Horizontal

Question 6

Describe where the flocculonodular lobe gets its name.

Answer 6

2 flocculi at either side of the vermis with the nodulus in the centre of the 2 flocculi

Question 7

Name and describe the peduncles of the cerebellum

Answer 7

Superior cerebellar connects the midbrain to the cerebellum (info leaving cerebellum goes out through the superior peduncle)

Middle cerebellar connects the pons (sensory information coming in) to the cerebellum

Inferior cerebellar connects the medulla to the cerebellum. Is the main sensory input route from the body

Question 8

Name the 4 deep nuclei of the cerebellum

Answer 8

Denate nuclei, Emboliform nucleus, Globose nucleus (interposed nucleus = emboliform nucleus+globose nucleus), Fastigial nuclei

Question 9

What is the role of the deep nuclei?

Answer 9

Information relay centres
They receive both excitatory and inhibitory inputs from within the cerebellar cortex
Most output from the cerebellum originate from these nuclei

Question 10

What is the main role of the cerebellum?

Answer 10

Subconscious control of smooth movement

Ensures movement is coordinated, well timed, spatially coherent and matches the motor plan

Question 11

How does the cerebellum control smooth movement?

Answer 11

It compares what the motor plan is to what’s happening in the real world in real time
• Detect errors
• Send out corrections

Question 12

What are afferent tracts?

Name all the afferent tracts of the cerebellum.

Answer 12

Relay incoming info from the body to the cerebellum

1. Reticulocerebellar tract
2. Corticopontinecerebellar tract
3. Vestibulocerebellar tract
4. Olivarycerebellar tract
5. Anterior spinocerebellar and rostrospinocerebellar tract
6. Posterior spinocerebellar and cuneocerebellar tract

Question 13

Describe the reticulocerebellar tract

Answer 13

Origin: reticular formation and enters the cerebellum Via: superior peduncle

Question 14

Describe the olivarycerebellar tract

Answer 14

Origin: olivary nuclei
Via: inferior peduncle (medulla)
Function: info related to unexpected movement e.g. loss of balance, reflex activity from spinal cord
Area of cerebellum: spinocerebellum (vermis), cerebrocerebellum (lateral zone)

Question 15

What 4 tracts give information on where the body is in space? What are the other general functions of these tracts?

Answer 15

Anterior spinocerebellar tract, rostrospinocerebellar tract, posterior spinocerebellar tract and cuneocerebellar tract

They are direct as information comes directly from sensory organs through these tracts to the cerebellum

Question 16

What peduncle do the anterior spinocerebellar tract, rostrospinocerebellar tract, posterior spinocerebellar tract and cuneocerebellar tract go through to reach the cerebellum?

Answer 16

Anterior spinocerebellar + rostrocerebellar tract go through superior peduncle

Posterior spinocerebellar + cuneocerebellar tract go through the inferior peduncle

Question 17

Describe the vestibulocerebellar tract

Answer 17

Origin: Vestibular nuclei and (in brainstem)
Via: enters the cerebellum at the inferior peduncle.
Function: Give info on where the head is in relation to space, balance and gravity and influences head and eye movement relative to gaze
Area in cerebellum: goes to flocunodular lobe and vermis

Question 18

Describe the corticopontinecerebellar tract.

Answer 18

Origin: motor cortex and pontine nuclei
Via: middle peduncle
Relays programming and execution of intended movement

Question 19

Describe the cuneocerebellar tract

Answer 19

Comes from joint receptors and muscle spindles, reports on position, velocity and force of muscle contraction from the upper limb (via inferior peduncle)

Question 20

Describe the posterior spinocerebellar tract

Answer 20

Brings subconscious proprioceptive info (from muscles, joints and skin mechanoreceptors) from the lower limb (via inferior peduncle)

Question 21

Describe the rostrospinocerebellar tract

Answer 21

Brings info from upper limbs about ongoing spinal cord activity (is less specific)

Question 22

What part of the body does the anterior spinocerebellar relay info from?

Answer 22

Lower limbs

Question 23

Name all the efferent tracts from the cerebellum (8)

Answer 23

Cerebellothalamocortical tract
Globose-emboliform-rubro tract
Cerebelloreticular tract
Cerebellovestibular tract
Vestibulospinal tract
Corticospinal tract
Reticulospinal tract
Rubrospinal tract

Question 24

Describe the cerebellovesticular tract

Answer 24

Origin: fastigial nucleus
Via: inferior peduncle (as this is shortest path)
Ends: vestibular nuclei
Function: Control eye movement, Contributes to postural control via vestibulospinal tracts
(Goes from cerebellum to vestibular nuclei. Vestibulospinal tract arises from the vestibular nuclei - cerebellum can influence the output of the vestibulospinal tract via the vestibular nuclei)

Question 25

Describe globose-emboliform-rubro tract

Answer 25

Origin: Interpose nuclei (i.e. globose and emboliform nuclei). Via: superior peduncle Ends: red nucleus. Functions: Influences rubrospinal tract

Question 26

Describe the cerebellothalamocortical tract

Answer 26

Origin: dentate nucleus Via: superior peduncle and thalamus Ends: cortex Function: Updates output of motor cortex, updates the motor plan, indirectly influences the tract that comes from the cortex (i.e. the corticospinal tract)

Question 27

Describe the cerebellorecticular tract

Answer 27

Origin: fastigial nucleus Via: superior peduncle Ends: reticular formation Function: Contributes to postural control via reticulospinal tract (Reticulospinal tract arises form the reticular formation so the cerebellum can indirectly influence the reticulospinal tract)

Question 28

What nuclei in cerebellum does the cerebellothalamocortical tract leave?

Answer 28

Dentate nuclei

Question 29

What nuclei in cerebellum does the globose-emboliform-rubro tract leave?

Answer 29

Interpose nuclei (i.e. globose and emboliform nuclei).

Question 30

What nuclei in cerebellum does the cerebellovestibular tract leave?

Answer 30

All fibres come from fastigal nuclei

Question 31

What nuclei in cerebellum does the cerebelloreticular tract leave?

Answer 31

Fastigal nucleus. Some fibres come from globose-emboliform-rubro tract

Question 32

How does the cerebellum influence the corticospinal tracts? What are corticospinal tracts

Answer 32

There are no direct cerebellar-spinal tracts. The cerebellum indirectly influences the corticospinal tract via nuclei of the cerebellum Tracts that start in the cortex and end in the spinal cord - they influence movement of limbs/trunk

Question 33

What is the overall function of the a) lateral pathways b) medial pathways

Answer 33

a) goal-directed movements | b) basic postural control

Question 34

Whats another name for the floculonodular lobe?

Answer 34

Vestibulocerebellum

Question 35

Name the 4 functional regions of the cerebellum

Answer 35

Floculonodular lobe Medial zone: vermis/spinocerebellum Intermediate zone: spinocerebellum Lateral zone: cerebellum

Question 36

What causes disruption to the cerebellar functioning?

Answer 36

Cerebellar stroke, MS, tumour, head injury, spinocerebellar conditions, Friedreich’s ataxia Sensory ataxia Vestibular ataxia

Question 37

Define ataxia

Answer 37

Greek for "lack of order" or "disorder" | Causes errors in direction, amplitude, force, Timing, Velocity

Question 38

What impairments does a disruption in cerebellar functioning cause?

Answer 38

Impairment of afferent input: insufficient data Impaired processing : within cerebellum Impairment of efferent output: incomplete output

Question 39

For what conditions is ataxia an umbrella term?

Answer 39

Dysmetria, dyssynergia, rebound phenomenon, hypotonia, intention tremor, dysdiadochokinesia, dysarthria, nystagmus

Question 40

Define dysarthria

Answer 40

Disorder of speech articulation

Question 41

Define nystagmus

Answer 41

Involuntary movement of the eyes, often up and down but also side to side and rarely rotary

Question 42

Define hypotonia

Answer 42

Reduced resistance to passive movement

Question 43

Define intention tremor

Answer 43

Oscillation about a joint • Finger-nose test • Postural tremor • Head tremor

Question 44

Define dysdiadochokinesia

Answer 44

Difficulty with rapid alternating movement

Question 45

Define dysmetria

Answer 45

``` Inaccurate amplitude • Misplaced force • Hypermetria • Hypometria ```

Question 46

Define dyssynergia

Answer 46

Decomposition of movement | • Errors in the relative timing of segmental components of multi-joint movements

Question 47

Define rebound phenomenon

Answer 47

lack of check, problems with braking

Question 48

Name all clinical assessments

Answer 48

``` Romberg test Rebound test Rapid alternating movement Hell-to-shin test Finger-nose test ```

Question 49

Where in the cerebellum is the head and trunk of the somatotopic map located? Where are the limb representations located?

Answer 49

Vermis | In the intermediate regions (at either side of the vermis)

Question 50

Describe the inputs/outputs of the floculonodular lobe

Answer 50

Inputs: from the vestibular nuclei Via: vestibulocerebellar tract Function: where the head is in space (as the head of the homunculus is here)