Neuro-Cerebellum

Front 1

The anterior and posterior lobe of the cerebellum are separated by what structure?

Back 1

The primary fissure

Front 2

Do the anterior and posterior lobes of the cerebellum have similar functions?

Back 2

Yes

Front 3

The anterior and posterior lobes of the cerebellum each have what two regions?

Back 3

1. Central region (vermis)
2. Lateral region (cerebellar hemispheres)

Front 4

What is the central region of the cerebellum called?

Back 4

The vermis

Front 5

What are the three functional divisions of the cerebellum called?

Back 5

1. Vestibulocerebellum
2. Spinocerebellum
3. Cerebrocerebellum

Front 6

The vestibulocerebellum contains what structure?

Back 6

The flocculonodular lobe

Front 7

The spinocerebellum contains what structures?

Back 7

The vermis and intermediate zones

Front 8

The cerebrocerebellum contains what structures?

Back 8

The lateral cerebral hemispheres

Front 9

What is unique about the flocculonodular lobe?

Back 9

-Oldest phylogenetically
-Termed archicerebellum
-Consists of nodulus and flocculus

Front 10

Where are the flocculus and nodulus in comparison to each other?

Back 10

-Nodulus in midline
-Flocculus is more lateral

Front 11

Why is the flocculonodular lobe referred to as the vestibulocerebellum?

Back 11

It is due to afferent and efferent connections with the vestibular apparatus

Front 12

Where is the intermediate zone of the cerebellum located? What structure is it a part of?

Back 12

Just lateral to the vermis; spinocerebellum

Front 13

Why are the vermis and intermediate zone called the spinocerebellum?

Back 13

It is due to connections with the spinal cord

Front 14

What functional portion of the cerebellum is the largest?

Back 14

The lateral cerebellar cortex (cerebrocerebellum)

Front 15

Why is the lateral cerebellar cortex referred to as the cerebrocerebellum or pontocerebellum?

Back 15

Because of connections with the cerebral cortex and pons

Front 16

All output from the cerebellum goes through what structures?

Back 16

The deep cerebellar nuclei

Front 17

What are the four pairs of deep cerebellar nuclei?

Back 17

1. Dentate
2. Interposed (globose and emboliform)
3. Fastigial
4. Vestibular nuclei

Front 18

The vestibular nuclei receive processed information from what structure?

Back 18

The flocculonodular lobe

Front 19

The output from the vestibular nuclei travels where? What does it do?

Back 19

To the medial motor systems for balance, axial control and eye movements

Front 20

The fastigial nucleus receives processed information from where?

Back 20

The vermis

Front 21

Output from the fastigial nucleus goes where? What does it control?

Back 21

To the medial descending motor systems; controls axial and proximal movement during ongoing execution of movement

Front 22

The interposed nucleus (globose and emboliform) receives processed information from what structure?

Back 22

The intermediate hemisphere

Front 23

Output from the interposed nucleus travels where? What does it control?

Back 23

To the lateral descending motor systems; controls distal movement during ongoing execution of movement

Front 24

Where does the dentate nucleus receive processed information from?

Back 24

The lateral cerebellar hemispheres

Front 25

Output from the dentate nucleus travels where? What does it control?

Back 25

To the integration areas of the brainstem and cortex (premotor cortex); important for initiation and planning of movement

Front 26

Are the afferent and efferent connections of the cerebellum ipsilateral or contralateral?

Back 26

Functionally ipsilateral, they remain uncrossed or cross twice

Front 27

The left side of the cerebellum receives information from and influences what side of the body?

Back 27

The left side, always ipsilateral

Front 28

Cerebellar connections to and from what two structures are crossed?

Back 28

1. Cerebral cortex
2. Red nucleus
-lateral descending pathways are crossed

Front 29

The vestibulocerebellum receives afferents from what two structures?

Back 29

1. Primary vestibular afferents from vestibular apparatus
2. Secondary vestibular afferents indirectly from vestibular nuclei

Front 30

Where do secondary vestibular afferents from vestibular nuclei enter the vestibulocerebellum? What do they provide information about?

Back 30

Through the inferior cerebellar peduncle; provide information about the position and movement of the head

Front 31

Where do efferents from the vestibulocerebellum travel? What do they influence?

Back 31

To the vestibular nuclei; influence equilibrium and eye movements, medial motor systems (more automatic movements)

Front 32

The vermis of the spinocerebellum receives afferents from what structures? Where do they enter? Where do they end?

Back 32

1. Axial and proximal body parts
2. Enter through the inferior cerebellar peduncle
3. End in the medial part of the cerebellum (vermis)

Front 33

Efferents from the vermis of the spinocerebellum travel where? What do they influence?

Back 33

To the medial motor systems via the fastigial nucleus (vestibular nucleus, reticular formation, motor cortex); influence axial and proximal motor control during ongoing execution of movement

Front 34

The intermediate zone of the spinocerebellum receives afferents from what structures? Where do they enter? Where do they end?

Back 34

1. Distal body parts
2. Enter through the inferior cerebellar peduncle
3. End in intermediate zone

Front 35

Efferents from the intermediate zone of the spinocerebellum travel where? What do they influence?

Back 35

To the lateral motor systems via the interposed nucleus (red nucleus, motor cortex); influence distal motor control during ongoing execution of movement

Front 36

The cerebrocerebellum receives afferents from what structures?

Back 36

The motor cortex, premotor area and SMA

Front 37

Where do afferents to the cerebrocerebellum synapse? Where do they enter? Where do they end?

Back 37

1. In the pontine nuclei of the pons
2. Pontine fibers cross to enter the cerebellum through middle cerebellar peduncle
3. Terminate in the lateral part of the cerebellar hemisphere

Front 38

Efferents from the cerebrocerebellum travel where?

Back 38

To integration areas of the motor system via the dentate nucleus to the red nucleus and premotor cortex

Front 39

Where do efferents from the cerebrocerebellum exit? What do they influence?

Back 39

Exit through the superior cerebellar peduncle; influence initiation, planning and timing of movement

Front 40

Is GABA excitatory or inhibitory?

Back 40

Inhibitory

Front 41

What is unique about Purkinje cells in the cerebellum? Where do they synapse onto?

Back 41

They are the only efferent (output) cell of the cerebellar cortex; they synapse onto the deep cerebellar nuclei

Front 42

The Purkinje cells contain what neurotransmitter? Is it excitatory or inhibitory?

Back 42

Contain GABA, so all output onto deep cerebellar nuclei is inhibitory

Front 43

Where do granule cells project? How are they related to Purkinje cells?

Back 43

-They project to the most superficial layer in the cerebellar cortex
-The axons (parallel fibers) are perpendicular to Purkinje cells
-Excitatory influence onto Purkinje cells

Front 44

What are three types of inhibitory interneurons in the cerebellum?

Back 44

1. Golgi cells
2. Basket cells
3. Stellate cells

Front 45

Explain lateral inhibition in the cerebellum

Back 45

-Basket cells inhibit off-beam Purkinje cells
-Increases contrast between Purkinje cells receiving excitatory input and those not receiving excitatory input
-Assumes some tonic background level of Purkinje cell activity
-Similar lateral inhibition found in visual system

Front 46

Where do mossy fibers synapse? Do they have many connections?

Back 46

Onto granule cells; synaptic connection with many granule cells

Front 47

Are there more mossy fibers or climbing fibers in the cerebellum?

Back 47

Mossy fibers

Front 48

One mossy fiber affects how may Purkinje cells?

Back 48

Many

Front 49

One Purkinje cell is influenced by how many mossy fibers? Is the influence from one mossy fiber weak or strong?

Back 49

Many mossy fibers; influence from one mossy fiber is weak

Front 50

Where do climbing fibers arise from?

Back 50

The inferior olivary nucleus of the medulla

Front 51

Where do climbing fibers synapse onto?

Back 51

Directly onto Purkinje cells

Front 52

Each climbing fiber synapses onto how many Purkinje cells? Each Purkinje cell receives input from how many climbing fibers?

Back 52

10 or fewer; one

Front 53

Are Purkinje cells weakly or strongly influenced by climbing fiber connections?

Back 53

Strongly, because a single action potential in a climbing fiber will cause a burst of firing in a Purkinje cell

Front 54

What is the function of the cerebellum?

Back 54

Coordinated movement. The cerebellum compares intended movement to actual movement and makes ongoing adjustments as necessary to carry out the task

Front 55

The cerebellum receives information about movement from what three sources?

Back 55

1. Corticopontine projections from the cerebral cortex
2. Ventral spinal cerebellar tracts from interneurons in the spinal cord
3. Dorsal spinal cerebellar tracts from muscle, joint and cutaneous receptors

Front 56

The corticopontine projections into the cerebellum provide information about what?

Back 56

Planned movement

Front 57

Ventral spinal cerebellar tracts provide information about what?

Back 57

Planned movement, information that has been processed and affected by spinal networks before movement begins

Front 58

Dorsal spinal cerebellar tracts provide information about what?

Back 58

Ongoing movement

Front 59

How does motor learning occur in the cerebellum?

Back 59

Climbing fibers have long-lasting effects on Purkinje cell activity, can cause complex discharge patterns in Purkinje cells

Front 60

Is there more frequent discharge from Purkinje cells during the learning of a task or after the task has been learned?

Back 60

During the learning of a task

Front 61

What are some typical deficits seen in a patient with a cerebellar lesion?

Back 61

1. Delay in the initiation of movement
2. Dysmetria during voluntary movements
3. Asynergia
4. Dysdiadochokinesia

Front 62

What is dysmetria?

Back 62

Inaccuracy in the range and direction of movement

Front 63

What is asynergia?

Back 63

The decomposition of movement (loss of smooth coordination between joint segments)

Front 64

What is dysdiadochokinesia?

Back 64

The inability to perform rapidly alternating movements

Front 65

What deficits are seen in a patient with flocculonodular syndrome?

Back 65

-Disturbances in equilibrium
-Problems with eye movements
-Semi-automatic movements like walking may be disturbed
-Unsteadiness of gait (gait ataxia)

Front 66

What deficits are seen in a patient with neocerebellar syndrome?

Back 66

-uncoordinated or ataxic movement of the trunk or limbs
-delay in initiation of movements
-difficulties in planning and timing of movements

Front 67

Lesions usually affect what structures in neocerebellar syndrome?

Back 67

-Both intermediate and lateral cerebellar cortex
-Interposed and dentate nucleus (so ataxic movements not limited to trunk/proximal extremitites or distal extremities)

Front 68

Learning new motor tasks might be impaired with lesions in what structures?

Back 68

The lateral cerebellar cortex or the dentate nucleus

Front 69

Is the cerebellum typically involved in CVA's?

Back 69

No