Cerebellum Flashcards
inferior cerebellar peduncle
input from medulla
middle cerebellar peduncle
input from pons/cortex
superior cerebellar peduncle
output from cerebellum
motor input to cerebellum
- via corticopontine fibers
- CONTRALATERAL middle cerebellar peduncle
output from cerebellum
superior cerebellar peduncle
–> CONTRALATERAL red nucleus –> VL of thalamus –> motor complex –> vestibular nuclei/ inferior olives
Mollaret’s Triangle
- self contained loop
- lesion = palatal myoclonus
layers of the cerebellar cortex
1) internal granular layer
- dense
- receives (almost) all inputs
2) molecular layer
- fewer cells
- dominated by tracts
3) Purkinje cells
- large cells
most incoming fibers (to cerebellum) synapse on ____________
most incoming fibers (to cerebellum) synapse on GRANULAR CELL dendrites (granular cell layer)
granule cell axons travel to _____________ and synapse on ____________
granule cell axons travel to MOLECULAR LAYER and synapse on PURKINJE CELL DENDRITES
input from inferior olives to cerebellum travels to _________
input from inferior olives to cerebellum travels to MOLECULAR LAYER DIRECTLY (bypasses granular layer) to synapse on Purkinje cells via climbing fibers
which type of fibers do input from inferior olive travel?
climbing fibers
which type of fibers do input from cortex travel?
mossy fibers
from the purkinje cells, where does the output travel to?
deep cerebellar nuclei
cerebellar areas
1) vestibulocerebellum
- FLOCCULOONODULAR LOBE
- caudal
- input from vestibular nuclei
- output to vestibular nuclei
vestibulocerebellum (lobe? location? input/output?)
FLOCCULOONODULAR LOBE
- caudal
- input from vestibular nuclei
- output to vestibular nuclei
spinocerebellum (lobe? controls? input/output?)
VERMIS, intermediate
- controls midline structures (trunk, legs)
- input from spinocerebellar tract, olives
- output to spinocerebellar tract, olives
neocerebellum (lobe? controls? input/output?)
MOST of the cerebellum (lateral hemispheres)
- upper limb control
- input from cortex via pontine nuclei
- output back to cortex via VL of thalamus
lesion of vestibulocerebellum causes
- instability
- nystagmus
- balance/gait ataxia
lesion of spinocerebellum causes
- truncal instability
- leg incoordination
- exaggerated postural reflexes
lesion of the neocerebellum causes
- clumsiness
- intention tremor
hemispheric syndromes
- incoordination
- dysmetria (over/under shoot target)
- intention tremor
- dysdiadochokinesis (difficulty with rapidly alternating movements)
acute cerebellar disease
- vascular (hemorrhages, infarcts)
- toxic exposure (mercury, toluene, meds)
- heat stroke
- anoxia
which cerebellar cells are most susceptible to injury?
purkinje cells
which acute cerebellar disease is the biggest concern?
vascular
subacute cerebellar diseases
WEEKS - MONTHS
- alcoholic (vermis)
- paraneoplastic
- post infectious cerebellar ataxia
- cerebellar tumors
- MS
chronic alcohol use causes damage to what part of the cerebellum?
VERMIS
-usually due to thiamine deficiency
paraneoplastic cerebellar disease
- subacute
- due to body’s immune response
- antibodies against purkinje cells
- rapidly progressive
cerebellar pontine tumor
-completely blocks 4th ventricle –> blocks CSF –> increased intracranial pressure
chronic cerebellar disease
- congenital cerebellar hypoplasia
- genetic disorders
- neurogenerative disorders
- metabolic diseases
