Neuroscience Week 4: Cerebellum Flashcards
1
Q
Overview of the motor system
A
2
Q
3 and the cerebellum
A
3
Q
Lobes of the Cerebellum
A
- Anterior Lobe
- Posterior Lobe
- Folliculonodular Lobe
4
Q
Identify Cerebellum
A
5
Q
Identify Cerebellum
A
6
Q
Deep Cerebellar Nuclei
4 listed
A
DONT EAT GREASY FOOD
Dentate
Interposed
- Emboliform
- Globose
Fastigial
7
Q
The point at which the fourth ventricle passes up into cerebellum is called
A
Apex
or
Fastigium (the fastigial nucleus is near this area)
8
Q
The cerebellum is attached to the brainstem by
A
3 Peduncles
- Superior peduncle
- Middle peduncle
- Inferior peduncle
9
Q
Identify and composed of?
A
3 Peduncles
10
Q
Superior Peduncle is composed primarily of
A
mainly Efferents
11
Q
Middle Peduncle is composed primarily of
A
Afferents
12
Q
Inferior Peduncle is composed primarily of
A
Afferents
and
efferents
13
Q
Dentate axons gives rise to?
A
Superior peduncle
14
Q
Identify cerebellar parts
A
15
Q
Cerebellar arteries
A
- Superior Cerebellar artery
- Anterior inferior Cerebellar artery
- Posterior inferior Cerebellar artery
16
Q
Posterior inferior Cerebellar artery AKA
A
PICA
17
Q
PICA AKA
A
Posterior inferior Cerebellar artery
18
Q
PICA originates from
A
Vertebral arteries
19
Q
Identify arteries
A
20
Q
AICA AKA
A
Anterior inferior cerebellar artery
21
Q
SCA AKA
A
Superior cerebellar artery
22
Q
SCA supplies
A
anterior lobe and the superior tip of the posterior lobe also parts of the pons **** check first aid *****
23
Q
PICA Supplies
A
posterior lobe
inferior cerebellum
**** check first aid *****
24
Q
AICA originates from
A
Basilar Artery
25
SCA originates from
Basilar artery
26
AICA Supplies
medial anterior and posterior lobes and flocculonodular lobe
parts of the medulla
\*\*\*\* check first aid \*\*\*\*\*
27
Cell types of the cerebellar cortex
Outermost layer
Molecular layer
Purkinje cell layer
Granular layer
28
The most abundant neurons in the brain
Granular layer
29
Topography of Purkinje projections
30
Hemisphere Purkinje projections
to Dentate Nucleus
31
Paravermal or medial hemisphere Purkinje projections
* to emboliform and globose
Interposed nucleus
32
Vermis Purkinje projections
to fastigial nucleus
33
Fastigial nucleus recieves Purkinje projections from
Vermis
34
Interposed Nucleus receives Purkinje projections from
Paravermal or medial hemisphere
35
Dentate nureceivescieves Purkinje projections from
Lateral hemisphere
36
Cerebellar somatotopy
37
vermis and paravermal area AKA
Spinocerebellum
38
Lateral hemisphere of cerebellum AKA
Cerebrocerebellum
39
Neocerebellum AKA
Cerebrocerebellum
40
Flocculus and nodulus AKA
Vestibulocerebellum
41
Lateral hemispheres of Posterior lobe of cerebellum functions
3 listed
* multi-joint movement of the limbs
* involved in learning and storage of sequential components of skilled movements (learning to play violin)
* Activity in this region and the dentate precedes activity in the motor cortex that commands a movement
42
Corticalpontine tracts
Primary cortices → pons to synapse on pontine nuclei → decussate and form middle cerebellar peduncle and synapse on cerebellar cortex in the granular cells → purkinje cells project out to dentate → axons from purkinje form superior cerebellar peduncle as the dentacticlethalmic fibers and decussate in the midbrain to the thalamus → to the left motor cortex
so overall decussates 2x and ends ipsilateral to origin
43
Lateral cerebellar lesions cause
ipsilateral alterations in targets
Ataxia
44
Lesions here: name area and effect
Lateral hemispheres of cerebellum or pontocerebellum
* Dysmetria
* dysdiadochokinesia
* Movement decomposition
* Action or intention tremor
* Dysarthria
* Cognitive alterations (inattention, memory alterations)
45
Common causes of Lateral Hemisphere Damage
4 listed
* Infarction (PICA or SCA)
* Hemorrhage
* Tumor
* Multiple Sclerosis
46
Anterior lobe function
* maintains coordination of limb movements while these are executes
* strongly connected with the spinal cord
47
Spinocerebellar pathway
Start in lumbosacral spinal cord ascending via dorsal columns in gracilis tract or cuneatus tract to nucleus dorsalis of Clarke (dorsal nucleus) ascend as dorsal spinocerebellar tract in posterolateral spinal cord and synapse in the accessory cuneate nucleus or gracilis nucleus and form the inferior peduncle and synapse in the anterior lobe of the cerebellum in the vermis or paravermis to purkinje cells of vermis or paravermis to the fastigial nucleus and project out via fastigiabulbar fibers via the inferior peduncle and make synapse with vestibular nuclei and connect with medial and lateral vestibulospinal tracts and regulate muscles for stability and equilibrium
* the most paravermal will project to the interposed and out through the superior peduncle to red nucleus to the rubrospinal tracts
48
Anterior cerebellar lobe damage common causes
* Alcoholism/thiamine (vitamin B1) deficiency
* Spinocerebellar tract demyelination in Vitamin B12 deficiency
49
Anterior cerebellar lobe damage Symptoms
* Gait ataxia
* lower limb ataxia
* some truncal ataxia
50
Hereditary Ataxias affect spinocerebellar loop
* Friedreich ataxia
* spinocerebellar ataxias
* ataxia telangectesia
51
Friedreich Ataxia Etiology
Trinucleotide repeat on chromosome 9
52
Flocculonodular lobe function
coordination of muscles associated with equilibrium and eye movements
53
flocculonodular lobe circuitry Vestibulocerebellar tract???
start in vestibular apparatus → vestibular ganglion → cranial nerve 8 → flocul
54
Vermal and paravermal damage common causes
4th ventricle tumor
MS
Cerebral palsy
Joubert Syndrome
55
Vermal and paravermal damage Symptoms
* Truncal ataxia (titubation)
* Nystagmus
* Oculomotor disturbances
* Balance alterations
56
medulloblastomas commonly seen in?
Children
57
medulloblastomas origin
originates in granular cells of the cerebellum and projects into the 4th ventricle
58
medulloblastomas Symptoms
reeling of trunk (truncal ataxia) stands on wide base
symptoms of elevated intracranial pressure (NV, Headache, papilledema)
59
Normal function of cerebellum
* planning movement
* motor coordination
* muscle tone maintenance
* control eye movements
* cognitive computation
60
Altered function of the cerebellum: planning movement
movement decomposition (asynergia) - initiation delay
61
Altered function of the cerebellum: Motor coordination
incoordination (terminal dysmetria, intention tremor, dysdiadochokinesia, dysarthria)
62
Altered function of the cerebellum: Muscle tone maintenance
hypotonia, pendular relfexes
63
Altered function of the cerebellum: Control of eye movements and equilibrium
* Nystagmus
* defective saccadic and eye pursuit movements
* vertigo
64
Altered function of the cerebellum: Cognitive computation
Planning, attention, working memory and visual-spatial deficits, blunting of affect disinhibited behavior; dysmetria of thought and emotion
65
66
normal and altered cerebellar functions
