Cerebellum and Basal Ganglia Flashcards
1
Q
what covers the Cerebellum
A
the tentorum cerebelli
2
Q
where is the cerebellum in the skull
A
posterior cranial fossa
3
Q
Function of the Cerebellum
A
Regulate Equilibrium
Control muscle tone and posture
Provide motor coordination for voluntary movements both in the near future future and during execution
4
Q
Roll of the Cerebellum in providing motor coordination for voluntary movements in the near future
A
Plans motor actions in space and time
5
Q
Roll of the Cerebellum in providing motor coordination for voluntary movements during execution
A
monitors ongoing motor activity
Adjusts the output of the motor cortex and several motor nuclei
6
Q
Primary Function of the Cerebellum
A
Motor adaption
7
Q
what does the cerebellum oversee
A
modification of the motor programs in response to envirnoment(walking up different inclines, or a homefield advantage)
8
Q
what is motor sequence learning a function of
A
the basal ganglia
9
Q
the types of basal ganglia
A
Caudate
Putamen
Globus Pallidus
10
Q
how is the cerebellum devided physically
A
anterior and posterior lobes
11
Q
the fractured nature of body part representation in the cortex
A
Fractionated somatotopy
12
Q
The Fractionated somatotropic organization of the Cerebellum
A
medial: axial muscles
Lateral: distal limbs muscles
13
Q
gyri looking strucutures of the Cerebellum
A
Folia
14
Q
the middle of the cerebellum
A
the Vermis (Vestibulocerebellum)
15
Q
area lateral to the Vermis
A
Paravermal area (spinocerebellum)
16
Q
The most lateral area of the Cerebellum
A
Pontocerebellum
17
Q
the 3 peduncles of the Cerebellum
A
Middle(largest)
superior
inferior
18
Q
sulci of the cerebellum
A
Fissures
19
Q
what separates flocculonodular lobe from the body of the cerebellum
A
Posterolateral fissure
20
Q
what devides body of cerebellum into anterior and posterior lobes
A
PRimary fissure
21
Q
anterior lobe gets info from
A
the spinal cord
22
Q
posterior lobe of cerebellum gets info from:
A
the pons and some from spinal cord
23
Q
deep Cerebellar nuclei
A
Dentate
Interposed Nucleus
Fastigal
24
Q
what Cerebellar Deep Nuclei contributes most fibers in SCP
A
Dentate
25
the 2 parts of the interposed nucleus
Emboliform Nuclus
| Globose Nucleus
26
what do Cerebellar Peduncles connevt
Cerebellum and Brainstem
27
Parts of the Inferior Cerebellar Peduncle
Restiform body
| Juxtarestiform body
28
what does the restiform body get inputs from
from the spinal cord and brain stem
29
what does the restiform body monitor
monitors muscle and limb movement
30
what does the Juxtarestiform body connect
Interconnects Vestibular Nuclei and Cerebellum
31
location of the middle Cerebellar peduncle
lateral to pons
32
were does the middle cerebellar peduncle get afferents
from contralateral basis pontis
33
roll of the middle cerebellar peduncle
relays motor signals from cerebral cortex
34
what does the superior cerebellar peduncle do?
efferents to red nucleus and thalamus (VL)
35
the 2 types of fibers that enter into the cerebellum
Mossy fibers
| Climbing fibers
36
mossy fibers take info from
spinal cord and brainstem
37
climbing fibers take information from
inferior olivary nucleus (olive) in rostral medulla
38
how do mossy fibers reach the cerebellar cortex
via inferior and middle cerebellar peduncles
39
how do climbing fibers reach the cerebellar cortex
via inferior cerebellar peduncles
40
where do mossy fibers synapse in the cerebellar cortex
synapse in granule layer then go to the Purkinje cell layer (piriform layer) to synapse in molecular layer
41
where do Climbing fibers synapse in the cerebellar cortex
synapse in the Purkinje cell layer (piriform layer) to synapse in molecular layer
42
from the Purkinje cell layer, where doesinformation travel
deep cerebellar nuclei
43
where does information that leaves the deep cerebellar nuclei go
Red nucleus in midbrain and thalamus
| Vestibular nuclei
44
how does Deep Cerebellar nuclei go to the Red Nuclues and Thalams
via superior cerebellar peduncles
45
how does Deep Cerebellar nuclei go to Vestibular Nuclei
Via inferior Cerebellar Peduncle
46
uniforminity of the Cerebellar Cortex
Uniform throughout
47
layers of the Cerebellar Cortex
Molecular Layer
Purkinje Cell Layer
GRanule Layer
48
location of the Molecular layer of the Cerebellar Cortex
Top layer
49
what is contained in the Molecular layer of the Cerebellar Cortex
Purkinje cell Dendrites
| Granule cell axons
50
location of the Purkinje cell layer of the Cerebellar cortexe
thin layer between molecular and GRanule layer
51
what is in the Purkinje cell layer
only axons to leave cortex
52
where is the Granule layer of the Cerebellar cortex
in the bottom of the cerebellar cortex
53
what type of neurons are Cortical Afferents
Excitatory (glutaminergic)
54
what type of neurons are Cortical efferents
inhibitory (GABAnergic)
55
roll of inhibition in Cortical Connection
large amounts of inhibition in cortical processing
56
the synapse between a mossy fiber and a Granule cell
excitatory
57
what does the Granule cells do when they pass through the molecular layer
splits into parallel fibers
58
what do parallel fibers synapse on
synapse on purkinje cells and golgi cells and Stellate and Basket cells (internerons)
59
purkinje cells that have synapsed with parallel fibers and Climbing fibers project an axon where
to the deep nuclei of cerebellum
60
type of neuron is a purkinje cell
inhibitory cells
61
what do Climbing fibers do with the Purkinje cell
climb up the dendrite of the purkinje cell and synapse everytime they cross
62
Mossy and climbing fibers send collaterals to what before axon enters the cortex
deep nuclei
63
Purkinje cell axons end where
in deep nuclei
64
what are the 2 neuronal populations of Deep nuclei
Mossy fibers into cerebellar cortex
| Projection neurons whose axons leave cerebellum
65
where does the deep nuclei project
into the cerebellum and out to different regions of the CNS
66
Cerebellar afferent projections
Vermis: Fastigal
Medial hemisphere: Interposed
Lateral hemisphere: Dentate
67
Cerebellar Afferents
Spinocerebellar tracts
Trigeminal Nerve
Special sense (Vision, hearing, vestibular)
Pontocerebellar
Olivocerebellar
Reticulocerebellar (parameidan and lateral reticular nuclei in the medulla)
Locus ceruleus and Raphe Nuclei
68
where do spinocerebellar tracts enter the cerebellum
Anterior: superior Cerebellar Peduncle
Posterior: inferiore cerebellar peduncle
Cuneocerebellar: inferior cerebellar peduncle
69
where does the trigeminal nerve enter the cerebellum
uses all 3 peduncles
70
where does the pontocebellar tract enter the cerebellum
middle cerebllar peduncle
71
where does the olivocerebellar tract enter the cerebellum
inferior cerebellar peduncle
72
where do reticulocerebellar tracts enter the cerebellum
inferior cerebellar peduncle
73
what projections from locus ceruleus and RAphe nuclei enter the cerebellum
serotonergic and noradrenergic projections
74
what does the locus ceruleus and raphe nuclei facilitate transmission in
mossy and climbing fibers
75
where the tectocerebllar tract comes from to enter cerebellum
ipsilateral colliculi
76
where the vestibulocerebellar comes from to enter cerebellum
ipsilateral vestibular nuclei
77
where does the sensorimotor cortex project
via corticospinal collaterals
78
where do sensorimotor cortex project onto
ipsilateral olivery nuclei
79
where do olivocerebellar fibers project
to contraleral cerebellar cortex thru the ICP
80
the inferior olivary nuclei goes to what in the cerebelum
posterior lobe
81
where does the accessory olivary nuclei go to in the cerebellum
anterior lobe
82
roll of olive with the cerebellum
aid in motor learning of new skills
83
the major output of the cerebellum
Cerebellar Peduncle
84
what is the cerebellum involved in
Equilibrium
Muscle tone and posture
Coordinating voluntary movement
85
what does the cerebellar pattern of input underlie
the zonal connection to the cortex
86
what is each cerebellar zone associated with
deep cerebellar nucleus
87
Location of the Vermis
In the midline of the cerebellum
88
what hemisphere is adjacent to the vermis
Medial hemisphere
89
what hemisphere is adjacent to the medial hemispher
Lateral hemisphere
90
vermis is what functionally
Vestibulocerebellum
91
the paravermal area is what functionally
Spinocerebellum
92
the lateral hemisphere is what functionally
Pontocerebellu
93
Input to the Vestibulocerebellum
Vestibular labyrinth
| Vestinular nuclei
94
Where is the Vestibulocerebellum location
Flocculonodular lobe as part of the vermis
95
nuclear output of the Vestibulocerebellum
Fastigial nucleus
| Bilateral VEstibular nuclei
96
how does the Fastigial nucleus leave the Vestibulocerebellum
via ICP
97
what are the Fastigial nucleus
bilateral vestibular nuclei
98
Function of the Vestibulocerebellum
control of eye movements in response to head movements via MLF
Balance
99
what tract does balance travel
Vestibulospinal tract
100
regulation of the activity(balance) of the VEstibulocerebellum
FIbers from Vestibular nuclei+CN8 project into cortex of cerebellum at the vestibulocerebellum
From the cortex these fibers project deep to Fastigial Nuclei
from the fastigial nucleus fibers leave the cerebellum via ICP back out to both Vestibular nuclei
101
Inputs to the Spinocerebellum
```
Spintal cord (spinocerebellar tracts)
Brainstem (trigeminal afferents)
```
102
Location of the Spinocerebellum
Paravermal area
| part of the Vermis
103
Output of the Spinocerebellum
1.the interposed nuclei project to the contraleral(Decussate in the midbrain) VA/VL of thalamus via SCP
this then talks to the limb area of the primary motor cortex
2. also projections to the contraleral red nucleus (magnocellular portion) via SCP
104
Function of the Spinocerebellum
Motor learning
Posture and gait
Coordination of trunk and limb movements
105
Input to the Neocerebellum
Motor cortex to basilar pons via contralateral MCP
106
location of the neocerebellum
Lateral cerebellar meisphers
107
Function of the Neocerebellum
Planning the timing of movements especially the upper extremity
coordination of speech
108
output of the neocerebellum
projects deep to the Dentate nucleus
| dentate nucleus projects to contralateral VA/VL of thalamus via SCP and contralateral REd nucleus via SCP
109
Right Cerebellum talks towhat
left Cerebral cortex to control right side of body
110
Neocerebellar loop
1. primary motor, premotor, and supllimary motor cortex project to basilar pons
2. Basilar pons project to contralateral lateral cerebellar cortex
3. Latearl Cerebellar cortex projects to Dentate nucleus
4. Dentate nucleus projects to contralateral Thalamus VA/VL by decussating in the superior cerebellar peduncle.
5. Thalamus VA/VL projects to primary motor, premotor, and supplementary motor cortex
111
CTCC Loop with spinal cord
1. Cerebral Cortex sends projects to Basilar pons and contralateral spinal cord(Corticospinal tract)
2. Basilar points sends fibers to Cerebellar cortex
2. 1 proprioception sends projections to spinal cord
2. 2 Spinal cord sends fibers to cerebellar cortex via the spinocerebellar tract (mossy fibers)
3. Cerebellar cortex sends fibers to cerebellar nucleus
4. Cerebellar nucleus sends fibers to contralateral thalamus
5. thalamus sends fibers to cerebral cortex
112
how does the cerebrum control muscles
1 cerebral hemisphere contralerally via the corticospinal tract
113
how does the cerebellum influence muscle
ipsilaterally because one half of cerebellum projects to contralateral thalamus (2 contralaterals equal 1 ipsilateral)
114
other functions of the cerebellum
Cognition
115
the most lateral aspect of each cerebellar hemisphere is connected to what
indirectly connected with lateral prefrontal cortex in cerebrum
116
when is lateral cerebellar activity highest
speech
117
description of lateral cerebelllar activity during speech
most prominent cerebellar activity is unilateral and consistent with dominant drontal cortex (where speech is represented)
118
when is cerebellar activity high during speech
during functional naming (Drive, fly) rather than object naming (Car, airplane)
119
does the cerebellum do only motor control of speech
no does more
120
Cognitive defect of a cerebellar stroke
decreased reasoning, inattention, grammatical errors, patchy memory loss
121
Affective defects of a cerebllar stroke
dulling of emotional responses, aberrant emotional behaviors
122
structures that yield distinctive kinds of movement disorders when damaged
Basal Ganglia
123
what makes up the Basal Ganglia
Striatum
Globus Pallidus
Subthalamic Nucleus
Substantia nigra
124
the striatum consists of what
caudate nucleus
nucleus accumbens
putamen
125
the globus pallidus consists of what
```
external segment (GPe)
Internal Segment (GPi)
```
126
the substantia nigra consists of what
```
compact part (SNc)
reticular part (SNr)
```
127
the LEnticular nucleus consists of what
putamen from the striatum
| and all the globus pallidus
128
Parts of the Caudate
head
body
tail
129
the Putamen coincides with what
insula
130
the Globus pallidus has outputs to where
extensive output to thalamus
131
Shape of Caudate
C shaped
| Part of wall of lateral venticle
132
Description of cinoact substantia Nigra
Densely packed
| Pigmented neurons
133
where does the COmpact Substantia Nigra project
diffuse modulatory dopaminergic projects to striatum
134
where is Reticular Substanita Niggra compared to compact
closer to cerebral peduncle
135
description of Reticular Substantia Nigra
non-pigmented neurons
136
what kind of nucleus is the Reticular substantia Nigra
basal ganglia output nucleus
137
what do Basal Ganglia Ciruits modulate
cortical output
138
what determines Basal Ganglia Circuit loop functions
where the start and end is (motor cognition, limbic, emo, motivation...)
139
Motor loop is for
Learned movement
140
cognitive loop is for
motor intentions
141
Limbic loop is for
emotional aspects of movemetn
142
Oculomotor loop is for
Voluntary saccades
143
Can basal Ganglia initiate movement
no, but active during all movements
144
Role of basal ganglia motor loop
Influence descending motor pathways by motdulating corical activity in motor ares
145
what specifical does the basal ganglia motor cloop aid in controlling
Scales strength of muscle contractins
146
what does the Basal Ganglia motor loop work with to organize requisite sequences of excitation of motor cortex needed for movement
With SMA
147
the 2 pathways of BAsal Ganglia motor loop
direct path
| Indirect pathway
148
neureons involved in the direct basal ganglia motor loop
5 sets of neurons
149
neurons involved in the indirect basal gnaglia motor loop
7 sets of neurons
150
Basal Ganglia Motor loop
Somatosensory and motor cortex-> Striatum (mostly putamen)-> GPi-> VA/VL in Thalamus-> Somatosensory and motor cortex
151
roll of Basal Ganglia Cognitive loop
Motor learning, planning movements ahead, especially complex movments
152
when does the Cognitive loop swich to the motor loop
when the new motor task is practiced to the point it can be "automatically executed, the motor loop (using putamen) becomes active instead
153
the Basal Ganglia Cognitive loop
Prefrontal cortex-> Caudate-> Globus Pallidus-> VA-> prefrotnal cortex
154
What is key in fine tuning pathway output
The presence of neurons with inhibitory and excitatory neurotrasmittersi in the same neural pathway
155
how excitatory response can lead to inhibition
Excitatory neuron activates and inhibitory neuron.
| This projects onto a 3rd neruon and conseuently silences a 3rd neuron.
156
how can an excitatory neuron, synapsing on a inhibitory neron, still lead to activation
excitatory neron synapses on an inhibtiory neuron
this inhibitory neron synapses on another inhibitory neron, inhibiting it from realeasing inhibitory neruotrasmitters.
Therefore the 4th nueron is not inhibited and can release stimuli
157
Basic ciruit of basal ganglia
Cerebral cortex sends excitiatory to striatum(Caudate, Puamen, Ventral striatum)
striatum sends inhibitory projects to GPi
GPi sends inhibitory to Thalamus via LEnticular Fasciculus and Ansa LEnticularis joining to form thalamic Fasciculus
Thalamus sends excitatory projects to Cerebral cortex via internal capsule and sends out motor output
158
how is the putamen and globus pallidus organized
somatotopically organized
159
organization of the putamen and globus pallidus allows for creation of what
direcct and indirect pathways
160
roll of the direct pathway
selective facilitation of neurons mediating a desired movement
161
roll of the indirect pathway
simultaneously disfacilitating other neurons that would have caused unwanted movemnt
162
how does the subthalamic nucleus suppress unwanted movements
somatotopic projections to globus pallidus interna
163
Basal ganglia direct pathway
Cerebral cortex sends excitatory to Striatum (Caudate, Putamen, and Ventral striatum)
Striatum inhibits the action of GPi
GPi sends inhibitory projections to thalamus via the LEnticular Fasciculus and Ansa Lenticularis that form the Thalamic Fasciculus
Thalamus sends fibers to the Cerebral Cortex
The Cerebral Cortex sends direct fibers to facilitate desired movements
164
Basal Ganglia, Indirect Pathway
Cerebral cortex sends excitatory fibers to Striatum
Striatum sends inhibitory fibers to GPe
GPe sends inhibitory fibers to subthalamus (this also gest excitatory fibers from cerbral cortex)
Subthalamus sends excitatory fibers to Gpi
GPi sends inhibitory fibers to thalamus Via Lenticular Fasciculus and Ansa Lenticullaris that eventually form the Thalmic Fasciculus.
The Thalamus sends excitatory fibers to cerebral crotex
the cerebral cortex sends excitatory fibers to neurons in the limbs
165
roll/pathway of substantia Nigra in the Basal Ganglia
SNc sends dopamine projects to stritaum and is excitatory or inhibitory depending on receptors on the striatum.
SNr modulates info from the subthalamus and sends inhibitory fibers to the thalamus and striatum
this ultimately changes the indirect and direct basal ganglia pathways
166
Kyperkinetic Movement disorders associated with the basal ganglia
involuntary movements
| chorea, athetosis, ballismus
167
Kypokinetic movement disorders associated with the basal ganglia
difficult initiating movment
168
perturbed muscle tone is a result of
fucked up basal ganglia
169
symptomes of perturbed muscle tone
general increase in flexor and extensor tone, rigidity of Parkinson's disease
If tone increase in some muscle body can be bend/twisted into abnormal, fixed posture; dystonia
tone can be decreased as well
170
What does huntington's disease result from
Degeneration of striatum (Caudate> Putamen)
171
Symptoms of Huntington's disease
chorea, rigidity, cognitive disturbences
172
genetics of huntington's disease
autosomal dominant, trinucleotide repeat
173
age of onset of Huntinton's disease
50, but is variable
174
damages to the subthalamus in the indirect pathway leads to
loss of subthalamic fibers, disinhibits thalamus, resulting in failure to suppress cortical outputs and involuntary movement (hemiballismus)
175
What does hemiballismus result from
due to a lesion in the subthalmus beacuse of a cerebrovascular accident (CVA stroke); branch of Posterior Cerebral Artery
176
symptoms of hemiballismus
Dramatic movements of limbs (flailing, rotatory)
| Affect one side of body, and affect arm and leg to different degrees
177
why does Parkinson's disease occure
lesion in the nigrostriatal fibers.
| substantia nigra compact part neurony bodiess contain Lew
178
when do people get parkinson's disease
60
179
Symptoms of PArkinson's disease
2-3 cardinal features: bradykinesia, resting tremor, rigidity
180
Treating PArkinson's disease
VA/VL and GPi lesioned selectively
Deep Brain stimulation
Stem cells
L-dopa medication
181
Deep Brain stimulation for parkinsons
Implant electrodes in subthalamus to provide long term stimulation and overcome abnormal activity in these structures
182
how does L-dopa work to treat parkinsons
replace lost dopamine due to nigrostriatl fiber degreneration
183
L-dopa treatment over time
Helpful, but response can fluctuate over time and can induce involuntary movement
