Cerebellum Flashcards
Functions of the cerebellum
- regulates equilibrium
- controls muscle tone and posture
- provides motor coordination for voluntary movements
- in near future (plans motor actions in space and time)
- during execution (monitors ongoing motor activity and adjusts output of motor cortex and nuclei)
What is the primary function of the cerebellum?
motor adaptation
- oversees modification of motor programs in response to environment
What functions in motor sequence learning?
basal ganglia (caudate, putamen, globus pallidus)
what is the somatotopic organization of the cerebellum?
in ant and post lobes
- termed fractionated somatotopy, refers to fractured nature of body part representation in cortex
What do the cerebellar peduncles interconnect?
cerebellum and brainstem
What does the posterolateral fissure separate?
flocculonodular lobe from body of cerebellum
What does primary fissure divide?
body of cerebellum into ant and post lobes
What is the major cerebellar efferent?
superior cerebellar peduncle
Injury to lateral hemisphere involvement of arm and speech results
intention tremor: upper extremity shakes as target is approached
dysdiadochokinesia: impaired ability to perform rapid alternating mvmts
dysmetria: lack of coordination of mvmt associated with hand, arm, leg and eyes (can’t perform finger to nose test)
dysarthria: uneven phonation (scanning or explosive speech)
vermis injury
truncal ataxia: disturbances in balance while seated, disrupted vestibulospinal tract fxn
gait ataxia: ant lobe lesion (sign alcoholism), can’t walk without feet wide apart, staggering walk
Vestibulocerebellum injurt
nystagmus; back and forth eye mvmts
How does cerebellum function in cognition
most lat aspect of each cerebellar hemisphere indirectly connected with lateral prefrontal cortex in cerebrum
When is lateral cerebellar activity highest?
during speech; most prominent cerebellar activity is unilateral and consistent with dominant frontal cortex
Results of strokes to cerebellum
cognitive defects: decrease reasoning power, inattention, grammatical errors, patchy memory loss
affective defects: dulling of emotional responses, aberrant emotional behaviors
