S2 Neuro Exam 4: Cerebellum

Front 1

How many fissures divide the cerebellum into how many lobes?

Back 1

Two transversely oriented fissures divide the cerebellum into three lobes.
Primary fissure: On superior surface, separates anterior and posterior lobe
Posterolateral (prenodular) fissure: On inferior surface, separates posterior lobe from flocculondular lobe.

Front 2

Name the parts of the cerebellum
(rostral view)

Back 2

Front 3

Name the parts of the cerebellum
(caudal view)

Back 3

Front 4

Name the parts of the cerebellum
(ventral view)

Back 4

Front 5

Name the parts of the cerebellum
(mid-sagittal view)

Back 5

Front 6

Lobules ______ correspond to the anterior lobe



*lobules are composed of folia (ridges)

Back 6

I-V

Front 7

Lobules _______ correspond to the posterior lobe

Back 7

VI-IX

Front 8

Lobule _________ correspond to the floculonodular lobe

Back 8

X

Front 9

Controls eye movement (MLF) & body equilibrium (VST)

Which functional division?
What is unique about this division?

Back 9

Vestibulocerebellum (flocculonodular lobe)


*STAYS w/i cerebellum

Front 10

Controls muscle tone & ongoing axial/limb movements

Which functional division?

Back 10

Spinocerebellum (vermis & paravermis)

Front 11

Plays a role in planning & initiation of movements

Which functional division?

Back 11

Cerebrocerebellum (lateral hemisphere)

Front 12

How many layers of cortex are there in the cerebellum?

Back 12

3 layers:
molecular layer (outer)
Purkinje cell layer (intermediate)
granular cell layer (inner)

Front 13

What types of neurons are within the cerebellar cortex (5 types) ?

Back 13

molecular layer: Basket & stellate intrinsic neurons
Purkinje cell layer: Purkinje cell principal neuron
Granule cell layer: granule & golgi intrinsic neurons

Front 14

How many deep nuclei lie within the deep cerebellar gray matter?

Back 14

Front 15

The cerebellum receives input in a somatotopic fashion (legs ant, face post, trunk midline, extremities lateral)

from what 3 sources?

Back 15

spinal cord (spinocerebellar & cuneocerebellar tracts)

vestibular system (vestibulocerebellar tract)

cerebral cortex (all cortico_______cerebellar tracts)

Front 16

What connect the cerebellum with the rest of the nervous system and how many are there?

Back 16

Three paired white matter structures-->
-Superior cerebellar peduncle (brachium conjunctiva):
efferent--> thalamus (dentatothalamic, dentatorubral)
afferent<--spinal cord

-Middle cerebellar peduncle (brachium pontis:
afferent<--Pons (pontocerebellar tract)

-Inferior cerebellar peduncle:
afferent<-- olivary nuc, spinal cord, etc (olivocerebellar tract*)
efferent--> reticular, vestibular

Front 17

What are the 2 main fiber systems of the cerebellum?


Which one transmits olivocerebellar input ONLY (from inferior cerebellar peduncle)?

Back 17

1. climbing fiber system
(transmits olivocerebellar input)

2. mossy fiber system
(most other input)

Front 18

Describe the Climbing fiber circuit


What type of NT is involved?

Back 18

Climbing fiber--> purkinje cell & deep cerebellar nuclei

EXCITATORY- aspartate

Front 19

Describe the Mossy fiber circut


What type of NTs are involved

Back 19

Mossy fibers--> Deep cerebellar nuclei & Granule cell axons (parallel fibers)--> purkinje & intrinsic
EXCITATORY- glutamate

Intrinsic neurons--> purkinje cell--> deep cerebellar nuclei
INHIBITORY- GABA
(*INtrinsic=INhibitory)

Front 20

Which circuit is highly focused, while the other has extensive divergence?

Back 20

Climbing fiber (CF) input is highly focused


(Mossy fiber granule cell input has extensive divergence)

Front 21

Signal for SPATIAL RESOLUTION

Back 21

INtrinsic stellate & basket cell axons from the plane of the parallel fiber project laterally & INhibit purkinje cells

Ex: inhibits flexors while you extend arm

Front 22

Signal for TEMPORAL RESOLUTION

Back 22

parallel fiber excitation of Golgi Type II neurons provides feedback INHIBITION to the granule cell (& mossy fiber)

Ex: inhibits extensors to release from extension

Front 23

What is the function of the inferior olivary nucleus (ION)?

What are the 2 types of recurrent olivo-cerebellar loops?

Back 23

sends error signals related to motor commands or timing to cerebellum--> motor learning/adaptation

1. olivocerebellar mesencephalic-olivary loop
2. olivocerebellar nucleo-olivary loop

Front 24

Which loop?
projects directly to INHIBIT contralateral ION
decreased synchronous discharge of ION
= focuses input by inhibiting all other fibers as it excites

Back 24

Olivocerebellar nucleo-olivary loop

Front 25

Which loop?
projects indirectly (via CTT) to ipsilateral ION
increased synchronous discharge of ION
= simultaneously excites both sides

Back 25

Olivocerebellar mesencephalic-olivary loop

Front 26

Cerebellar output is via the deep nuclei. Which ones project via spinocerebellum?

which via cerebrocerebellum?

Back 26

spinocerebellum (to spinal cord):
fastigial nucleus (in medial vermis)
lateral vestibular nucleus (in lateral vermis)
globose & emboliform nuclei (in paravermis)

cerebrocerebellum (to cerebral cortex)
dentate nucleus (in lateral hemisphere)

Front 27

Globose & emboliform nuclei, located in the paravermis, project to the spinal cord via the ______________ & to the red nucleus

Back 27

rubrospinal tract

Front 28

Fastigal nucleus, located in the medial vermis projects the the ___________

What is the main function?

Back 28

spinal cord


involved in extraocular movement (MLF) & medial motor system (vestibulospinal & reticulospinal)

Front 29

Dentate nucleus, located in the lateral hemisphere, projects to the cerebral cortex & the __________

What is the main function?

Back 29

thalamus (VL)


Provides output to the primary motor (M1). premotor, prefrontal, & posterior parietal cortex

Front 30

What is the main function of the entire cerebellum?

Back 30

(motor)
-error detection & correction of movement
-planning & initiation of movement

Front 31

What does A HAND(3) Tremor stand for?

Back 31

A – ataxia (uncoordinated; unsteady movement)

H – hypotonia (decreased muscle tone, passive)
A – adiadochokinesia (inability to perform rapid alternating movements)
N – nystagmus (jerky eye movements)
D(3) – dysarthria (speech disturbance),
dysmetria (difficulty measuring distance), dyssynergia (breakdown in movement, jerky )

Tremor – shaking

= SIGNS of CERELLAR DISORDERS!!

Front 32

What type of tremor?
slow, course shaking during attempted voluntary movement
amplitude increases towards end of movement

Back 32

intention (kinetic) tremor

Front 33

What type of tremor?
oscilating movements of shoulders & arms when arms are outstretched
occurs during maintenance of position against gravity

Back 33

static (postural) tremor

Front 34

What type of tremor?
oscillatory movements of head or trunk
rocking motion front to back, side to side, or rotatory

Back 34

Titubation

Front 35

Describe gate ataxia (truncal ataxia)

Back 35

wide based, clumsy, staggering gate (appear drunk)

Front 36

Describe check & rebound in a patient w/ a cerebellar disorder

Back 36

- removal of pressure applied to flexed forearm = unchecked flexion
- tapping of outstretched arm = oscillation of arm around intial position (rebounding)

Front 37

Describe the pendular reflex in a patient w/ a cerebellar disorder

Back 37

tapping patellar tendon elicits reflex w/ leg swinging continuously back & forth

Front 38

What type of cerebellar lesions would affect the trunk?

the limb?

Back 38

vermis lesions affect the trunk


hemispheric lesions affect limb

Front 39

A Unilateral cerebellar lesion will lead to (ipsilateral/contralateral) signs & symptoms

Back 39

ipsilateral

(due to double crossed circuitry)

Front 40

What type of lesions would produce more severe signs;
deep nuclei or superior cerebellar peduncle
OR
cerebellar cortex?

Back 40

lesions of deep nuclei or superior cerebellar peduncle are more severe

Front 41

which cerebellar syndrome?
disequilibrium, truncal ataxia, head tilt
nystagmus, dysmetria, smooth pursuit deficits
involves floculonodular lobe & vermis

Back 41

midline syndrome

Front 42

which cerebellar syndrome?
A HAND(3) Tremor
involves intermediate & lateral zones

Back 42

lateral syndrome

Front 43

which cerebellar syndrome?
combination of midline & lateral syndrome
bilateral signs
involves trunk, limbs, & eyes

Back 43

pancerebellar syndrome

Front 44

Which artery supplies?
Deep cerebellar nuclei
superior cerebellar peduncle
rostral middle cerebellar peduncle
rostral pons

Back 44

Superior cerebellar artery

Front 45

Which artery supplies?
flocculus
caudal middle cerebellar peduncle
caudal pons

Back 45

Anterior Inferior Cerebellar artert (AICA)

Front 46

Which artery supplies?
inferior vermis
tonsil & nodulus
choroid plexus of 4th ventricle
inferior cerebellar peduncle

Back 46

Posterior inferior cerebellar artery (PICA)