Cerebellum Flashcards
What is the function of cerebellum?
Integrates sensory information to be used primarily
in the regulation and control of motor functions
Does the cerebellum give rise to any tracts projecting to spinal levels?
NO!
The cerebellum consists of __ hemispheres; __ lobes; median _____
2; 3; median vermis
The cerebellum is located in the _____ cranial fossa _____ to brain stem.
posterior; dorsal
Is cerebellum related to to falx cerebelli and tentorium cerebelli?
YES!
What matter is found in the cerebellar cortex, and what is the shape of it?
Gray matter; folia
What matter is found in the cerebellar medullary center? What types of axons are found here?
White matter; Afferents/Efferents
How many pairs of central nuclei is found in the cerebellum?
4 pairs
Primary fissure of the cerebellum divides _____ and _____
Anterior lobe and posterior lobe
What are the 3 deep nuclei found in the cerebellum?
Fastigial, Gblobose and emoliform (in human and apes) contains nucleus interpositus, and dentate
Axons from fastigial, globose and emboliform, and dentate nuclei projects to _____ nuclei and _____.
Brainstem nuclei and thalamus
What are the Efferents crossing Superior cerebellar peduncle?
Nucleus interpositus and dentate nucleus to contralateral ventral lateral nucleus of thalamus and red nucleus
What are the Afferents that crosses Middle cerebellar peduncle?
Contralateral pontine nuclei
What are the Afferents that crosses inferior cerebellar peduncle?
Cord, lateral cuneate nucleus, inferior olivary nucleus, reticular formation, vestibular nucleus
What are the 3 layers of cerebellar cortex? (Sup-Deep)
Molecular layer, Purkinje cell layer, Granule cell layer (MPG)
Is Folium white or gray matter?
White matter
Which of the 3 layers is this?
Closely packed small neurons; main receptive layer of fibers originating outside cerebellum
Granular (deepest)
Which of the 3 layers is this?
Single row of purkinje cells; axons project to deep nuclei
Purkinje cell layer
Which of the 3 layers is this?
Few neuron cell bodies; mostly a synaptic and integrative area
Molecular layer
What are the 5 cells that forms intracortical circuits?
- Granule
- Purkinje
- Basket
- Golgi
- Stellate
Which of the 5 cells that forms intracortical circuits is excitatory, and what transmitter is released?
Granule (glutamate)
Which of the 5 cells that forms intracortical circuits that their axons are output of cortex, excitatory or inhibitory?
Purkinje cells (inhibitory; GABA)
Which of the 5 cells that forms intracortical circuits has axons around purkenje cells excitatory or inhibitory?
Basket cells (Inhibitory; GABA)
Which of the 5 cells that forms intracortical circuits is inhibitory (GABA) to mossy fibers?
Golgi cells
Which of the 5 cells that forms intracortical circuits that most synapse with purkinje cells? excitatory or inhibitory?
Stellate cells (Inhibitory; GABA)
Which of the 5 cells that forms intracortical circuits is inhibitory (GABA)?
Purkinje, basket, golgi, and stellate
Which of the 5 cells that forms intracortical circuits is the only one that is excitatory (glutamate)?
Granule
Input from inferior olivary nuclei will use which fiber?
Climbing fiber
Input from all other sources besides inferior olivary nuclei uses what fiber?
Mossy fiber
Olivocerebellar tract uses which fibers?
Climbing fiber (Climb to pick olives)
All other tracts uses what fibers?
Mossy fibers
Archicerebellum gives rise to which lobe?
Flocculonodular lobe (Fish and amphibians)
Paleocerebellum gives rise to which lobes?
Superior vermis of anterior lobe and inferior vermis of
posterior lobe
Neocerebellum are only found in?
Mammals, humans
Vestibulocerebellum (flocculonodular lobe):
- Adjustment of muscle tone in response to _____ stimuli
- Coordinates actions of muscles that maintain _____ and ______; participates in other motor responses to vestibular stimuli
- (e.g., _____ movements)
vestibular; balance and posture; eye
Spinocerebellum contains _____ lobe vermis
and adjacent
_____ zones
anterior; paravermal
Spinocerebellum
(anterior lobe vermis
and adjacent
paravermal zones):
-Controls tone and synergy of _____muscles, as appropriate, at any moment for adjusting posture and automatic movements
-Input from cord, trigeminal nuclei, inf. olivary nuc., RF
collaborating;
Pontocerebellum is equivalent to?
Neocerebellum
Pontocerebellum/Neocerebellum (lateral parts of hemispheres):
-Ensures a smooth and orderly sequence of muscle contractions and intended precision in force, direction, and extent of voluntary movements, especially in _____ extremities
upper (pointing at nose test)
Pontocerebellum/Neocerebellum (lateral parts of hemispheres): Input from cerebral cortex
via _____ _____ nuclei (volitional movements anticipated or in progress)
contralateral pontine
What is this syndrome called?
Characterized by abnormalities in the timing, range, force, speed, and sequencing of muscle contractions and resultant movements
Ataxia
Flocculonodular lobe syndrome:
-Lack of coordination of _____ muscles (truncal
ataxia)
-Walks on _____ base; trunk constantly reeling and swaying
-Most often seen in children with _____.
paraxial; wide; medulloblastomas
Anterior lobe syndrome:
- Loss of coordination mostly in _____ limbs
- Gait instability; walk as if drunk, i.e., staggering and reeling in a _____ manner
- Extremely difficult to do the _____ test
lower; stiff-legged; heel-shin
What is posterior lobe syndrome?
Loss of coordination of voluntary skilled movements (ataxia)
Posterior lobe syndrome: Intention tremor – during the movement. What does this mean?
Unable to direct the limb to a target; swaying to and from
Posterior lobe syndrome: Dysmetria and “past pointing” what does this mean?
Inability to control the range of a movement; overshoots or undershoots the target
Posterior lobe syndrome: Dysdiadochokinesia what does this mean?
Inability to perform rapid alternating movements such as repetitive hand pronation and supination
Posterior lobe syndrome: Speech may be affected (dysarthria) what does this mean?
Decreased muscle tone
