Lecture 1- Cerebellum Flashcards
The cerebellum regulates… and controls…. tone and posture. It also provides … for voluntary movements.
In the near future:
Plans … in space and time
During execution:
Monitors …. motor activity
Adjusts the …. of the motor cortex and several motor nuclei
- equilibrium
- muscle
- motor coordination
-motor actions
- ongoing
- output
Primary function of cerebellum is …
it works with basal ganglia to do this
motor adaptation
example: walking up/downhill instead of flat
Motor sequence learning is the function of the…
basal ganglia
The cerebellum is located in the posterior cranial fossa; below the …
tentorium cerebelli
Instead of gyri, the cerebellum has… which are bands of gray matter
folia
In the cerebellum, the sulci are called…
fissures
The… area of the cerebellum is also called the vestibulocerebellum
flocculonodular lobe
The medial hemisphere of the cerebellum is the…
Paravermal area
The lateral hemisphere of the cerebellum is the…
Pontocerebellum area
The purpose of folia is to…
increase cortical surface area
The…. fissure separates the anterior lobe from posterior lobe in the cerebellum
Primary
The… fissure separates the flocculonodular lobe from rest of body of cerebellum
Posterolateral
4 cerebellar deep nuclei
- Fastigal
- Globose
- Emboliform
- Denate
Most axons of the cerebellum stay in the cerebellum except from the axons of the …
deep cerebellar nuclei
The…. nucleus is the biggest deep cerebellar nuclei and it contributes most fibers in Superior Cerebellar Peduncle
Denate
The Emboliform and Globose form the…. nucleus.
Which is more medial?
- Interposed
- Globose
The… nucleus is small and right by the midline and is connected to the flocculonodular lobe
fastigal
The cerebellum has 3 peduncles:
inferior
middle
superior
The Inferior cerebellar peduncle had 2 parts:
Restiform body
Juxtarestiform body
The Restiform body of the inferior cerebellar peduncle has inputs from … and… and it monitors…
- spinal cord
- brainstem
- muscle and limb movement
The Juxtarestiform body of the Inferior cerebellar peduncle interconnects… and…
- vestibular nuclei
- cerebellum
The… cerebellar reduncle is also called the branchium pontis and is the largest. It is lateral to the pons, has afferents from contralateral basis pontis and relays motor signals from cerebral cortex
middle
The…. cerebellar peduncle is also called the branchium conjunctivum and has mostly efferent fibers to red nucleus and thalamus (VL)
Superior
Information from the spinal cord and brainstem are … fibers
mossy
Information from the contralateral inferior nucleus (olive) in rostral medulla are… fibers
climbing
Mossy fibers from the spinal cord and brainstem travel via .. and … cerebellar peduncles and they synapse in …
- inferior
- middle
- granule layer (in bottom of cerebellar cortex)
After the mossy fibers synapse in the granule layer of the cerebellar cortex, the axons go to the….
Purkinje cell layer (piriform layer)
The purkinje cells are the only ones that…
leave the cerebellar cortex to talk to the deep cerebellar nuclei
From the deep cerebellar nuclei, the fibers from dentate and interposed nuclei go via the superior cerebellar peduncle to the…. and…
OR
from the fastigal, via the inferior cerebellar peduncle (juxtarestiform part) to the…
- red nucleus (midbrain)
- thalamus (VL)
- vestibular nuclei
The climbing fibers travel from the…. via …and then synapses…
- inferior olivary nucleus (olive) in rostral medulla
- inferior cerebellar peduncle
- in molecular layer of purkinje cell dendrites
The spinocerebellar tracts are afferent and the anterior goes through the… peduncle, the posterior goes through the…. peduncle and the cuneocerebellar goes through the … peduncle
- superior
- inferior
- inferior
The trigeminal is a cerebellar affferent and it uses … peduncles
all 3
Special sense (vision, hearing, vestibular) cerebellar afferents are… and…
- tectocerebellar tract ipsilateral colliculi
- vestibulocerebellar from ipsilateral vestibular nuclei
The pontocerebellar is a cerebellar afferent and uses the… peduncle
middle cerebellar
The olivocerebellar (climbing fibers) is a cerebral afferent and uses the… peduncle
inferior cerebellar
The reticulocerebellar (paramedian and lateral reticular nuclei in medulla) is a cerebral afferent and uses the… peduncle
inferior cerebellar
Origin of Posterior spinocerebellar tract? and body part represented?
Does it cross midline?
Peduncle used to enter cerebellum?
Major inputs?
- Clarke’s nucleus (T1-L2/3)
- Trunk, leg
- no
- inferior
- mechanoreceptors in muscle, joints, skin
Origin of anterior spinocerebellar tract? Body part represented? Does it cross midline? Peduncle used to enter cerebellum? Major inputs?
- Spinal border cells (T12-L5)
- trunk, leg
- 2x, first in cord and then in cerebellum
- superior
- mechanoreceptors, movement-related interneurons
Origin of cuneocerebellar tract? Body part represented? Does it cross midline? Peduncle used to enter cerebellum? Major inputs?
- lateral cuneate nucleus in medulla
- trunk, arm
- no
- inferior
- mechanoreceptors in muscles, joints, skin
The olive is in the
rostral medulla
The sensorimotor cortex projects via…. onto ipsilateral…
- corticospinal collaterals
- olivary nuclei
Olivocerebellar fibers project to… through Inferior cerebellar peduncle
contralateral cerebellar cortex
Info from the inferior olivary nuclei go mostly to the…. lobe
posterior
Info fro the accessory olivary nuclei go mostly to the… lobe
anterior
Climbing fibers enter cerebellum via… and then they divide into…. branches and the synapse as the only climbing fiber on a particular purkinje cell but they synapse hundreds of times
- Inferior cerebellar peduncle
- 5-10
Olivocerebellar tract: At rest, groups of olivary neurons synchronously discharge and cause
complex spikes in purkinje cells
Complex spikes is the occurrence of …. in one neuron in response to a single AP from another neuron
multiple APs
Olivocerebellar tract: With training, performing a motor task purkinje cell discharges are…
simple spikes (produced by parallel fibers)
If unexpected obstacle to learned motor task is encountered, …. result each time obstacle is encountered.
As animal learns to overcome obstacle, complex spikes…
- complex spikes
- decrease in # and eventually disappear
Inferior olivary nuclei are involved in motor learning and the…
acquisition of new motor skills
The red nucleus is located in the… and is believed to be a …
- rostral midbrain
- novelty detector
Input to the red nucleus are collaterals from…. and….
- cerebral cortical fibers descending to olive
- cerebellar output fibers ascending to thalamus
The output of the red nucleus is…
Inhibitory to ipsilateral olivary nucleus
If a mismatch is detected between the intended movement and the movement that is performed then the…. may release appropriate olivary neurons until the two align
red nucleus
The cerebellar cortex is uniform throughout and has 3 layers:
Molecular layer
Purkinje cell layer
Granule layer
The molecular layer of the cerebellar cortex contains….
purkinje cell dendrites and granule cell axons
The purkinje cell layer of the cerebellar cortex contains only…
axons to leave cortex
Cerebellum is involved in…,… and…
- equilibrium
- muscle tone and posture
- coordinating voluntary movements
the cerebellum has…. somatotrophy. Trunk is represented more… and limbs more…
fractured
medially
laterally
Each cerebellar zone is related to a particular,..
deep nucleus
The …. is the longitudinal zone of the lateral hemisphere and projects to dentate nucleus
pontocerebellum
The… is the longitudinal zone of the medial hemisphere (paravermal area) and is associated with interposed nucleus (globulous and emboliform)
spinocerebellum
The…. longitudinal zone is the midline and is associated with the flocculonodular lobe, vermis and fastigal nucleus
vestibulocerebellum
Input for the vestibulocerebellum
vestibular labyrinth
vestibular nuclei
Output of vestibulocerebellum
fastigal nucleus>vestibular nuclei
vestibular nuclei
The function of the vestibulocerebellum longitudinal zone
- control of eye movements in response to head movements
- balance
Cerebellar efferent: vestibulocerebellum:
From fastigial nucleus; fibers project to…. via … with contralateral projection through cerebellar white matter (unicinate fasiculus)
- bilateral vestibular nuclei
- ICP
Cerebellar efferent: vestibulocerebellum:
Output to medial and lateral vestibular nuclei control… through…
- eyes
- medial longitudinal fasiculus (MLF)
Cerebellar efferent: vestibulocerebellum:
Output to ipsilateral lateral vestibular nucleus mediates…
balancing function of vestibulospinal tract
Cerebellar efferent: vestibulocerebellum:
Some purkinje cell axons don’t…. and exert direct…. on …
- synapse in fastigial nucleus
- tonic inhibition
- lateral vestibular nucleus
Input of spinocerebellum
spinal cord (spinocerebellar tracts) brainstem (trigeminal afferents)
Output of spinocerebellum
- interposed nucleus
- –red nucleus (magnocellular portion)
- ——rubrospinal and reticulospinal pathways
- VA/VL of thalamus
- -limb area of primary motor cortex
Function of spinocerebellum
- posture and gait
- coordination of trunk and limb movements
Cerebellar efferents: Spinocerebellum:
From interposed nucleus, axons leave through… and mostly terminate in:
-contralateral…. : those ending in pontomedullary RF regulate function of…. in…
OR
-contralateral…. which is involved in motor learning
- SCP
- reticular formation
- tectospinal tract
- posture and locomotion
- red nucleus
Function of pontocerebellum or neocerebellum
- planning the timing of movements especially of UL
- coordination of speech
Output of pontocerebellum
Dentate nucleus
- red nucleus-parcocellular portion (inferior olivary nucleus)
- VA/VL of thalamus (all motor cortex and parietal lobe)
Input of pontocerebellum
motor cortex- basiliar pons- MCP
Cerebellar efferents: Pontocerebellum:
From the dentate nucleus; forms large… which is most of…
The…. then decussates in…
The collaterals goto the…
Synapses in….. of thalamus
Then info projected by VL neurons to motor areas of cerebral cortex
- dentatorubrothalamic tract
- SCP
- SCP
- caudal midbrain
- red nucleus
- ventral lateral nucleus
One cerebral hemisphere controls… muscles (corticospinal tract)
contralateral
One half of cerebellum influences …. limbs
One half of cerebellum projects to … thalamus
ipsilateral
contralateral
Lateral hemispheres function is planning …. movements, those that become more…. and… with practice
- learned, skilled
- precise
- rapid
Injury to lateral hemisphere of cerebellum involves… and…
arm and speech
An…. is when upper extremity shakes as target is approached, hand may overshoot target. This could be an injury of the…. hemisphere
- intention tremor
- lateral
…. is rapid alternating movements. This could be an injury of the … hemisphere
- Dysdiadochokinesia
- lateral
… is the finger to nose test. Injury to… hemisphere could affect this
- Dysmetria
- lateral
… is uneven phonation ( production of vowel sounds) aka scanning or explosive speech. It could be an injury of the…. hemisphere
- Dysarthria
- lateral
The function of the medial hemispheres is
adjusting limb movements
Function of vermis
postural adjustments
Injury of the vermis could cause…. which is disturbances in balance while seated, also standing and gait ataxia. This is caused by disrupted …. function
- truncal ataxia
- lateral vestibulospinal tract
… is an anterior lobe lesion where a person cant walk without feet wide apart and staggering walk (even when sober)
gait ataxia
The function of the vestibulocerebellum
Flocculus and vermis important in eye movements
Injury of the vestibulocerebellum could result in…. which is back and forth eye movements
Nystagmus
cerebellum has a role in … and … naming
functional (drive, fly)
object (car, plane)
lateral cerebellar activity highest during..
-speech
strokes in cerebellum can cause …. defects such as decrease in reasoning power, inattention, grammatical errors and patchy memory loss. Or … defects like dulling of emotional responses, abberent emotional behaviors
- cognitive
- affective
