cerebullum Flashcards
(46 cards)
What is the embryologic origin of the cerebellum?
Alar plate of the embryonic metencephalon
The cerebellum forms the roof of the 4th ventricle.
Name the four main divisions of the cerebellum.
- Vermis
- Paravermal zones
- Hemispheres
- flocculonodular lobe: flocculus = lateral nodulus = midline of vermis)
The flocculonodular lobe is also a significant part of the cerebellum.
Which cerebellar peduncle is primarily afferent? (cerebrum - medulla)
Caudal cerebellar peduncle
input from spinal cord and vestibular
It receives input from the spinal cord and vestibular system.
What is the appearance of the white matter core of the cerebellum?
Arbor Vitae
It has a tree-like appearance surrounded by grey matter cortex.
What are the three layers of the cerebellar cortex?
- Molecular layer
- Purkinje cell layer
- Granule cell layer
What type of fibers originate from the olivary nucleus?
Climbing fibers
They provide profound excitation of Purkinje cells and are involved in motor learning.
What is the primary function and input of the flocculonodular lobe?
Equilibrium & vestibular reflex coordination.
input: vestibular system
It receives input from the vestibular system.
True or False: The cerebellum initiates movement.
False
no conscious8 sensory perception
The cerebellum modulates movement but does not initiate it.
What is motor ataxia?
Exaggerated, uncoordinated movement
It differs from proprioceptive ataxia as it does not involve paresis.
Which tract carries proprioceptive information from the hindlimbs?
Dorsal spinocerebellar tract (DSCT)
What signs may indicate a lesion in the flocculonodular lobe?
- Broad stance
- Falling
- Nystagmus
What is an intention tremor?
Tremors seen during movement, not at rest
Head tremors may often be observed during eating or drinking.
Fill in the blank: The cerebellum does not have direct influence on _______.
lower motor neurons
What is cerebellar hypoplasia commonly caused by in kittens?
Feline panleukopenia virus infection during gestation
This condition results in fewer granule cells and static cerebellar ataxia.
What is the major output from the cerebellum? (cerebellum - midbrain)
Rostral cerebellar peduncle
It contains mostly efferent fibers.
What is the function and input of the vermis and paravermal zones?
Posture, muscle tone, coordination
input: spinocerebellar tracts
They receive input from the spinocerebellar tracts.
Which spinocerebellar tract carries information from the forelimbs?
Cuneocerebellar tract (CCT)
True or False: Cerebellar signs are typically contralateral to the lesion.
False
Cerebellar signs are usually ipsilateral to the lesion.
How does the cerebellar cortex influence motor systems?
Inhibits deep cerebellar nuclei
This inhibition provides a tonic excitatory output.
What is hypermetria?
Excessive limb movement, ‘high stepping’
It is a sign of cerebellar dysfunction.
What are the signs of delayed voluntary movements indicative of?
Lateral hemisphere lesions
what is the major input for the cerebellum? (ENTIRELY afferent) (cerebellum - pons)
Middle cerebellar peduncle.
input from pontine nuclei
3 deep cerebellar nuclei of arbor vitae
fastigial (medial
interposed
lateral (dentate)
molecular layer of cerebellum
most superficial
purkinje DEDRITES, granule axons, interneurons
