Medulla Flashcards
(31 cards)
Role of the cerebellum in motor control
a. coordinates movement
b. regulates and maintains muscle tone
c. equilibrium and balance
Cerebellum receives and processes unconscious proprioceptive info regarding what?
How does it enter as well.
1) vestibular system (vestibulocerebellar pathway), ENTERS VIA inferior peduncles
2) muscle spindles (re: muscle length) and Golgi tendon organs (re: muscle tension), joint receptors (spinocerebellar pathways) ENTERS VIA Superior and Inferior peduncles
For motor control does the cerebellum receive auditory/ visual and sennsory systems?
yes they receive all above and info regarding the motor commands/plans via input from cortical areas BA 4 and 6 via the
1) corticopontocerebellar pathway, ENTERS VAI middle peduncle
Where do plans from area 4 and 6 enter in the cerebellum
ENTERS VAI middle peduncle
Does cerebellum initiate movement?
No, Cortex does.
What is the cerebellum involved with?
a. timing of motor movements
b. progression of movements
c. coordinates agonist and antagonist muscles
d. helps to sequence movements
e. monitors body status and makes corrective adjustments in motor activities
Cerebellum cell layers Purkinje
Middle project to deep nuclei
modualte activity of deep nuclei
release inhibitory
Granule cells
Are excitatory , most numerous
Cerebellar lobe anterior
regulates muscle tone via input from spine, receives proprioceptive info and GDS info and plays a role in posture and equilibrium
Cerebellar lobe middle
role in motor coordination, planning and programming, has reciprocal connections with motor and sensory cortices
Flocculonodular
regulation of muscle tone, posture, equilibrium, and coordination of eye movements
Cerebellar zone median vermal
movements of axial body, fastigial nucleus, homunculus for axial body
Cerebellar zoneIntermediate
control of muscle contractions in distal limbs, influences lateral CS tract, interposed and emboliform nuclei, homunculus for limbs and face
Cerebellar zone Lateral
coordination of sequential movements and learning of complex sequential movements, influences lateral CP tract, dentate nucleus
A disruption in the timing of cerebellar inhibition and excitation will result in
a disruption in movement
The cerebellum is involved with the synergy of rapid alternating movements and fine coordination of the muscles for speech.
True
Both the lateral and intermediate zones influence the lateral cortical spinal tract.
True
The flocculonodule lobe plays a role in
coordination of eye movements
Ataxic dysarthria results in
slurred speech
reduced intelligibility
irregular articulatory breakdowns
Cerebellar output must first travel through the__________________before traveling to areas 4 and 6 in the motor cortex.
VL nucleus of thalamus
Cerebellar output is via the deep nuclei.
True
Climbing fibers originate in the ___________and are __________to ____________________cells.
pons ; inhibitory ; Purkinje
medulla ; excitatory ; Purkinje
Mossy fibers from the cerebrum, spine, and brain stem enter the cerebellum and (choose all that apply)
excite the deep nuclei
excite the granule cells
What percentage of cerebellar cortex can be seen from the outside of the cerebellar surface?
15%
