Cerebellum Flashcards
how many lobes in the cerebullum
3
what are the 3 lobes in the cerebellum
anterior, posterior, and flocculondoular
What are the 4 rules of 3 in the cerebellum
3 functional subdivisions, 3 pairs of peduncles, 3 pairs of deep nuclei and 3 cortical layers
what are the 4 functions of cerebullum
Movement coordination, maintenance of posture, maintenance of muscle tone and balance, motor learning
what percentage of neurones in the cerebellum
80%
where is the cerebellum situated
posterior brainstem
what does the cerebellum integrate
sensory input and motor outputs making it an ideal location for motor learning
damage to the cerebellum causes..
severe movement disruption but not complete movement abolition-
what is axtia
abnormal execution of multi jointed voluntary movements (n lack of coordination)
what can axtia be caused by
stroke, multiple sclerosis and tumor/ brain damage
what are the 3 deep cerebellar nuclei
denate, interposed and fastigial nucleus
what is a penduncle
a large bundle of neurons that are in the shape of a stalk
What are the 3 cerebullar penduncies
superior, middle and inferior
what are the 3 cerebellar cortex
cerebrocerebellum, spinocerebellum, vestiobulocerebellum
the cerebellum is connected to the what aspect of the brain stem
dorsal
the cerebellum is connected to the dorsal brainstem by what
3 symmetrical pairs of peduncles
state the 2 facts about the superior peduncle
no input and output to motor cortex - via thalamus and red nucleus
state 2 facts about middle peduncle
no outputs, inputs from motor cortex via pons.
state 2 facts for inferior peduncle
inputs from the inferior olivary nucleus, spinal cord, and vestibular nuclei, outputs to reticular formation - brainstem, spinal cord, and vestibular nuclei.
what does the cerebellar cortex do
integrates inputs from the cortex, brainstem and spinal cord and regulates motor outputs.
what are the 2 inputs for cerebrocerebellum
pons, from motor cortex - via thalamus
inferior olive, motor c. and via red nucleus and spinal cord
what is the output for cerebrocerebellum
denate nucleus , to motor c. via thaalmus
what does the corocerebellum do
involved in motor planning and projects to and from the cerebral, (motor cortex)
cerebrocereebllum is the what hemisphere
lateral ( located on the bottom)
what 2 parts comprise the spinocerebellum
vermis and intermediate cortex
what does the spinocerebellar do
regulates body and limb movements
what are the 2 input for spinocerebellum
vermis - head and trunk and intermediate cortex - limbs
where is the spinocerebellar located in the cerebellar cortex
at the top
what are the 2 inputs for the spinocerebellum
Vermis - [spinal cord carrying sensory info. from trunk and head
intermediate cortex - spinal cord carrying sensory info. from limbs
what are the 4 out puts for spinocerebellum
vermis - fastigial nucleus to medial descending tracts - reticulospinal and vestibulospinal tracts and motor execution
intermediate cortex- motor planning and lateral descending tracts of corticospinal and rubrospinal tracts
what is the output for vestibulocerebellum?
vestibular nucleus to axial and proximal muscles - limb extensors and head and eye muscles
what is the input for vestibulocerebellum
vestibular nucleus from semicircular canals and otolith organs
what is the other name for vestiobulocerebellum
flocculondular lobe
what does the vestiobulocerebellum do
regulates balance and eye movements
what are the 3 deep cerebellar nuclei
fastigial, denate and interposed
where is denate nuclei located
cerebrocerebellum
where is the deep interposed nuclei located
intermediate cortex
where is the fastigial deep nuclei located
vermis in spinocerebellum
what is the output for fastigial deep nuclei
to the reticular formation and vestibular nucleus via inferior peduncle
what is the output for denate deep nuclei
motor cortex via superior peduncle and thalamus
what is the output for the interposed deep nuclei
red nucleus via superior peduncle
where does the cerebellar cortex receive input from (3)
pontine nuclei, inferior olive (climbing fibers only ) spinal cord and vestibular nuclei.
what are the 3 cerebellar cortex outputs
cerebrocerebellum - denate nucleus
spinocerebellum - interposed and fastigial nuclei
vestiobulocerebellum- vestibular nuclei
what is the 3 points of out puts for cerebrocerebellum
cerebrocerebellum - denate nucleus - premotor cortex - motor planning
what are the 3 points of outputs ofr spinocerebellum
spinocerebellum - interposed and fastigial nuclei
what are the 3 ouputs for vestiobulocerebellum
vestiobulocerebellum- vestibular nuclei- neurons in the spinal cord and brainstem (balance and vestibulo-ocular regulation)
what are the 5 elements in cerebellar circuitry
mossy fibers, granule cells, climbing fibers, Purkinje cells and parallel fibres
how many layer re there in the cerebellar circuitry
3
what are the 3 layers in the cerebellar circuity
granule, Purkinje and molecular
what layer in the cerebellar circuity is deep to superficial
deepest is granule layer and most superficial is molecular
what type of fibres crosses a purkinje cell
parallel fibres
dendrite receive afferent information from what 2 fibres
climbing and parallel
what is the output of purkinje cells
deep cerebellar nuclei
what is the ratio of input for purkinje cells
40:1 input to output
what is the function of purkinje cells
release a NT called GABA, which inhibits neurons and reduces transmission of nerve impulses - they control/ coordinate and regulate movement —– inhibit
what are mossy fibres
primary neurons that carry information into cerebellum
can activate granule cells and cerebellum nuclei
granule cells attach to what type of fibre
parallel fibres
after the granule cell and parallel fibres attach, what occurs
they synapse with dendrites of Purkinje cells
what occurs when the Purkinje fibres are activated
inhibit cerebellar nuclei which modulates motor output
the climbing fibre does what
excites the Purkinje cells directly
(can sense signals to elicit learning)
the eye blink response is an example of what
cerebellum sensorimotor learning
what are major inputs via
mossy and climbing fibres
cerebellum receives inputs from where
the brainstem and spinal cord
cerebellum outputs go where
thalamus and brainstem
climbing fibre activation leads to what
learning by changing Purkinje cell response to mossy fibre input
