Cerebellum Flashcards
What is the function of the cerebellum?
balance and posture coordinated voluntary movements motor learning (fine tuning) motor tonus cognitive function: language
How are the peduncles of the cerebellum arranged?
sup. peduncle: to midbrain
middle peduncle: to pons, largest peduncle
inferior peduncle: medulla
input to cerebellum via mid. and inf. peduncles
output of cerebellum via sup peduncle
Which are the nuclei of the cerebellum?
dentate nc
interposed nc (emboliform and globose)
fastigeal nc
What cells can be found at the cerebellar cortex?
3 layers:
granule cell layer: granule and golgi cells
purkinje cell layer: purkinje cells (only ones leaving cerebellar cortex)
molecular cell layer: stellate and basket cells
except of granule cells, all others use GABA
What type of fibers give input to cerebellum?
climbing fibers
mossy fibers
aminergic fibers
What happens when there is a lesion in the archicerebellum?
problems with:
truncal ataxia towards the site of lesion
stance and gait
posture
head postures
oculomotor dysfunction (nystagmus and ocular dysmetria)
What happens when there is a lesion in the paleocerebellum?
problems with: truncal ataxia executing movements regulation of posture and muscle tone hypotonia
What happens when there is a lesion in the neocerebellum?
problems with: limb ataxia dysarthria hypotonia intention tremor oculomotor disorder
Describe dyssynergia
lack of speed and skill while performing activities requiring coordinated activity
no synergistics on smooth movements, instead: jerky erratic, disorganized
Describe dysmetria
error judging the distance, speed, power, direction of movement
movements are too slow or too quickly with too much or too little force
Describe dysdiadochkinesia
inability to make fast repetitive movements
Describe intention tremor
most commom type of cerebellar tremor, occurs when making purposeful movement
Describe dysarthria
slow articulation, ataxic, slurred explosive speech due to dyssynergy of muscles of phonation
Describe hypotonia
muscle flaccidity, decreased tonic output, flabby muscles, unnatural attitudes
What is the difference between cerebellar and sensory ataxia
very similar
sensory ataxia: due to problem of peripheral nerves
eyes open shows no problem in movement and coordination, eyes closed reveals problem
cerebellar ataxia: eyes open or closed makes no difference
