Neuroscience Week 4: Cerebellar histology and circuitry

Question 1

cerebellum cell count

Answer 1

• The cerebellum has a vast surface area, however, and when stretched, it has a rostrocaudal expanse of roughly 120 centimeters, which allows it to hold an estimated one hundred billion granule cells — more cells than exist within the entire cerebral cortex.

Question 2

THE TWO MAIN CLASSES OF CEREBELLAR NUCLEI

Answer 2

• The cerebellar cortical neurons
• The deep cerebellar nuclei

Question 3

CEREBELLAR CORTICAL CELL LAYERS

Answer 3

deep to superficial

• Granule layer
• Purkinje layer
• Molecular layer

Question 4

Identify Cerebellum layers

Answer 4

Question 5

cerebellum’s remarkable rehabilitation in cerebellar stroke

Answer 5

cerebellum’s extraordinary cell count plays an important role

Question 6

Granule layer properties and contents

Answer 6

• (highly cellular)
• Contains granule cells, Golgi cells, and unipolar brush cells.

Question 7

Purkinje layer Properties and contents

Answer 7

• A single layer of large Purkinje cell bodies.
• Purkinje cells project a fine axon through the granule cell layer.

Question 8

Identify layers and contents

Answer 8

Question 9

Molecular layer properties and contents

Answer 9

Primarily comprises cell processes but also contains stellate and basket cells.

Question 10

DEEP CEREBELLAR NUCLEI

Answer 10

From medial to lateral:

• Fastigial
• Globose
• Emboliform
• Dentate

Question 11

The globose and emboliform nuclei are also known as the

Answer 11

interposed nuclei

Question 12

A classic acronym for the lateral to medial organization of the deep nuclei

Answer 12

“Don’t Eat Greasy Food,” for dentate, emboliform, globose, and fastigial.

Question 13

Identify and cell type

Answer 13

Purkinje cell

Question 14

Fastigial nucleus plays a role in

Answer 14

the vestibulo- and spinocerebellum.

Question 15

Interposed nuclei are part of the

Answer 15

spinocerebellum.

Question 16

Dentate nucleus is part of the

Answer 16

pontocerebellum.

Question 17

Identify Deep Cerebellar Nuclei

Answer 17

Question 18

Three main types of cerebellar afferent fibers

Answer 18

• Climbing fibers
• Mossy fibers
• Multilayered fibers

Question 19

Multilayered fibers AKA

Answer 19

monoaminergic fibers

Question 20

Climbing fibers

Originate solely from

Answer 20

the inferior olive and pass via the contralateral inferior cerebellar peduncle to the cerebellum.

Question 21

Climbing fibers neurotransmitter type

Answer 21

Debate exists as to whether climbing fibers use the excitatory neurotransmitter aspartate or glutamate, but it seems most probable that they use glutamate.

Question 22

Mossy fibers type and derived from?

Answer 22

Excitatory fibers derived from diffuse cell populations within the brainstem and spinal cord.

Question 23

Mossy Fibers neurotransmitter type

Answer 23

They, like the climbing fibers, mostly use the excitatory neurotransmitter glutamate.

Question 24

These olivocerebellar fibers are distinct in that each Purkinje cell is

Answer 24

These olivocerebellar fibers are distinct in that each Purkinje cell is innervated by a single olivocerebellar climbing fiber.

Question 25

Three main types of cerebellar afferent fibers exist, which innervate

• Climbing fibers
• Mossy Fibers
• Multilayered fibers

Answer 25

both the deep cerebellar nuclei and the cerebellar cortex.

Question 26

These olivocerebellar fibers represent

Answer 26

represents the inferior arm of the triangle of Guillain-Mollaret

Question 27

Multilayered fibers derived from

Answer 27

Derived from neurobehavioral centers in the brainstem and diencephalon, such as the locus coeruleus, raphe nucleus, and the tuberomammillary nucleus of the hypothalamus.

Question 28

Multilayered fibers neuron type

Answer 28

• the role of the multilayered fibers is less uniform.
• They are considered monoaminergic because their cells of origin are generally associated with a single neurotransmitter type:
• the locus coeruleus is noradrenergic,
• the raphe nucleus is serotinergic,
• the tuberomammillary nucleus is histaminergic.

Question 29

the tuberomammillary nucleus is

Answer 29

Histaminergic

Question 30

the raphe nucleus is

Answer 30

Serotonergic

Question 31

the locus coeruleus is

Answer 31

noradrenergic,

Question 32

The deep cerebellar nuclei send excitatory fibers to

Answer 32

structures throughout the central nervous system.

Question 33

The majority of efferent information that leaves the cerebellum does so from the

Answer 33

deep cerebellar nuclei, which act through the excitatory neurotransmitters glutamate, most notably.

Question 34

The molecular and granule cell layers

Answer 34

filter and temporally pattern information as it is transmitted to the Purkinje layer

Question 35

The Purkinje layer is the sole recipient of

Answer 35

this post-processed information and sends inhibitory fibers to the deep cerebellar nuclei via the inhibitory neurotransmitter gamma-aminobutyric acid (GABA).

Question 36

Thus the cerebellar cortex, acting through the Purkinje layer, is an

Answer 36

important modulating force on the deep cerebellar nuclei.

Question 37

Identify Fiber type

Answer 37

Question 38

Identify Fiber origin and neurotransmitter used

Answer 38

Question 39

Deep Cerebellar Nuclei innervates and neurotransmitter

Answer 39

CNS with excitatory fibers using glutamate

Question 40

Identify fiber type and neurotransmitters used

Answer 40

Question 41

the majority of efferent information that leaves the cerebellum does so through the?

Answer 41

Deep cerebellar nuclei using glutamate to CNS targets

Question 42

The Purkinje fibers send out what kind of information to where

Answer 42

The Purkinje layer is the sole recipient of this post-processed information and sends inhibitory fibers to the deep cerebellar nuclei via the inhibitory neurotransmitter gammaaminobutyric acid (GABA)

Question 43

Purkinje fibers neurotransmitter type

Answer 43

GABA