Cerebellum Flashcards
what does the cortex do
say what is to be done
what does the basal ganglia and cerebellum do
how something is o be done
quality and organisation of movement
what kind of matter is basal ganglia
grey matter
what does the basal ganglia sp do
receive and prices info form cerebral cortex
feedback info to cortex via thalamus
no direct sp connection only via cortex
what are the components of the basal ganglia
putamen globus pallidus caudate nucleus internal capsule - outside amygdala
what are the connections of the basal ganglia
to motor cortex via thalamus
what role does basal ganglia play
acts like accelerator for cortex
what is the basic feedback circuit for basal ganglia
putamen receives input form motor cortex
globus pallidus - braking effect on thalamus output structure of basal ganglia
thalamus tim drive on patterns of motor cortex
what does the globus pallidus do automatically
supply brake to the thalamus
what does caudate do
input from frontal c. cortex
planning organisation thought processes not motor
what does sub thalamic nucleus do
promote brake on thalamus and c cortex
what would happen if there is damage to the sub thalamic nucleus
uncontrolled flailing of limbs
hemiballismus
no braking
what does disorders of the basal ganglia produce
changes in muscle tone and involuntary movements
what is dyskinesia
tremors
if dage to basal ganglia
what is athetosis
writhing movement
what is chorea
jerky, rapid movements, twitches, grimaces
what is ballismus
flailing limb movements proximal joints
what are the features of parkinson
resting tremor rigidity paucity of movement depression impaired cognitive function
what happens to the substantial nigra in parkinson
substantia nigra in midbrain loss of neurones that relate dopamine (dopaminergic) to putamen
what re ways of treatment of parkinson
L-dopa
dopamine agonists
transplant
ablation/stimulation
what is the L-dopa treatment
unlike dopamine crosses the BB barrier
effects reduces with time and produces its own dyskinesia effects
what is the dopamine agonist
bromocriptine
COMT inhibitors- prevents metab of L-dopa
what is transplant for parkinson treatment
foetal dopamine prod cells sourcing tissue difficult
what is the ablation/stimulation treatment do for
of thamlic nuclei can alleviate rigidity restore fucntoinin
what si the (subconscious) motor control centre
feedback loop to cortex via thalamus
cerebellum listens silently and talks back
what are functions of cerebellum
skilled rep moves (plan coord) –> cortex
locomotion/posture (monitor move coord) –> Ctx/BS/spinal cord
balance (monitor coord) –> vest spinal cord
what is predominate cerebellum matter
white with grey nuclei
what si the structural features of the cerebellum
lobes –> ant, post, flocculonodular
fissure –> primary, horizontal
vermis
what does cerebellum listen to cortex for
command for movement, intense activity in cerebellum
what are cortico-ponto-cerbellar tracts
enter cerebellum at middle cerebral penducle
what does cerebellum listen o spinal cord for
dorsal spinocerbelar tracts - unconscious position sense
enter via int penducel
ipsilateral damage
what does the cerebellum get from brainstem
balance info
non crossed
form vestibular nuclei from cochlea
inf olivary nucleus carry new motor programmees
where des cerebellar output form
via dep nuclei in cereblluma nd vestibule nuclei
what re some of the grey matter nuclei in cerebellum
fastigial - medial - posture
dentate- fine motor control
how does cerebellum answer the motor cortex
activation of corticospinal tract
control same side ipsilateral as non crossed organ
what are the function of the cerebellum
quality of movement
plans, coord, fine skilled
learned motor
integrates balance
what happens if cerebellar malfucnitno
signs disease ipsilateral disturbed balance modified muscle tone -hypotonia ataxia poor coord vermal lesion
