Cerebellum Flashcards
What are the three parts of the cerebellum?
- Spinocerebellum
- Cerebrocerebellim
- Vestibulocerebellum
Spinocerebellum Function
- Regulation of muscle tone
- Coordination of skilled voluntary movement
Cerebrocerebellum Function
- Planning and modulation of voluntary activity
- Storage of procedural memories
Vestibulocerebellum Function
- Control of balance and eye movements
Label this photo
Purple: Spinocerebellum
Blue: Cerebrocerebellum
Green: Vestibulocerebllum
Label this
- Purple: Hemisphere
- Pink: Vermis
- Yellow: Flocculonodular Lobe
- Blue: Flocculus
- Green: Nodulus
Vermis is latin for
Worm
What does the vermis do?
Coordinated trunk and proximal limb movements (Shoulders and hips)
What does the intermediate part do? Where is it located?
- Coordination of distal extremities (arms, legs, hands, feet)
- Lateral to vermis
What does the lateral part do? Where is it located?
- Function: unknown; possible cognition and motivation
- lateral to intermediate limb
The vermis and intermediate part are involved in ____ and ____
Motor Learning and Balance
What does the Flocculonodular Lobe do? Where is it located?
- Function: Coordinate eye movement and balance
- Located “caudally”
- Made up of nodulus (central) and floculus (lateral)
The cerbellum is connected to the brainstem via ____. Where do they connect?
- 6 peduncles, 3 on each side.
- Superior Peduncles associated with midbrain
- Middle Peduncles associated with Pons
- Inferior Peduncles associated with Medulla
True or False: The cerbellum is able to initiate movments
False. No movement are initiated from within cerebellum. It modifies or refines movement based on sensory information and trial/error.
Can cerebellar testing be performed when someone is asleep?
No, need to be awake and moving
Cerbellar problems produce ____ disorders but are not associated with ____.
- movement
- weakness/paralysis
What does the basal ganglia do?
Modfies movement through facilitation and inhibition; heavily involved wiht initiation.
Cerebellar Motor Pathways influence muscles on the ____ side of the involved cerebellar lobe.
Ipsilateral
This will be a board question.
The cerebellum mediates movments through what feedback mechanisms?
- Spinocerebellar Pathway; Proprioceptive information from the joints and muscles
- Vestibulocerebellar pathway; equilibrium inputs
- Corticopontocerebellar pathway; cerebral motor cortex (what is planned and what sensory feedback tell us)
It takes the senses and uses it as feedback
What types of information get brought into the spinocerebellar tract?
- Brings in information concerning joint, tendon and muscle proprioception, tone, pressure and touch
- Sensory information from muscles, tendons and joints
Spinocerbellar Tract
Spinocerebellar Dorsal Cross Section Tracts
Vestibulocerebellar Pathway
- Comes from ear through vestibular nerve to vestibular nucleus then goes to cerebellum via inferior cerebellar peduncle (flocculonodular node). Then goes to both vestibular nucleus and then out to axial muscles for postural control.
- Ipsilateral input; bilateral output.
- Postural control stuff here; axial muscles
Input: vestibular apparatis
Output: muscle
The vestibulocerebellar tract is involved with
balance information and postural muscles
What information runs in the Corticopontocerebellar Tract?
- Cerebral input for coordination of muscle activity
- Specifically what gets activated and the strength of activation
Corticopontocerebellar Pathway
What explains why the middle cerebral peduncle is so big?
Almost all motor coordination information goes through it!
Alternative visual for corticopontocerebellar tract
Common signs of cerebellar dysfunction
Complex motor dysfunction
* Changes in speed and cadence of speech (does not cause paralysis, causes incoordination of muscles)
* Temor (Action or “Intention” Tremor); incoordinated movements of muscles
* Eye movment abnormalities (nystagmus or oscillopsia)
Mild Dysfunction
* Dysmetria: inability to judge range of limb movements, without watching them
Severe Dysfunction
* Diskinesia: inability to perfom limb movements smoothly and efficently, even when watching
Cerebellar Severity of Symptoms is proportional to…
- The amount of tissue destroyed
- Not necessarily the location
Asthenia
- Lack of muscular strength due to incoordination, not paralysis
Ataxia
- Inability to maintain balance while walking due to incoordination
Fatigability
Due to incoordination, muscles work against each other
Hypotonia
Muscles feel flabby and offer less resistance to passive displacement
Dysdiadochokinesia
Difficulty with rapid alternating movements
