cerebellum Flashcards
what fissure subdivides the cerebellum into the anterior and posterior lobes?
primary fissure
what fissure subdivides the cerebellum into the flocculonodular lobe?
posterolateral fissure
name the regions of the cerebellum medial to lateral
vermis, intermediate part (paravermis), lateral
the lateral regions on each side of the vermis in the cerebellum are called what?
cerebellar hemispheres
spinocerebellum is composed of what region(s)?
the paravermis and vermis
cerebrocerebellum is composed of what region(s)?
lateral hemisphere
vestibulocerebellum is composed of what region(s)?
flocculonodular lobe
the anterior lobe of the cerebellum is supplied by what?
a) PICA
b) AICA
c) superior cerebellar artery
d) ACA
c) superior cerebellar artery
the posterior lobe of the cerebellum is supplied by what?
a) AICA
b) ACA
c) superior cerebellar artery
d) PICA
d) PICA
the flocculonodular lobe of the cerebellum is supplied by what?
a) ACA
b) PICA
c) AICA
d) superior cerebellar artery
c) AICA
the three cerebellar peduncles are called what?
- Superior cerebellar peduncles
- Middle cerebellar peduncles
- Inferior cerebellar peduncles
inferior cerebellar peduncles convey (afferent or efferent) fibers carrying (non-conscious or conscious) proprioception to cerebellum from three places.
afferent, non-conscious
what three locations do the afferent fibers in the inferior cerebellar peduncles convey information from and which fibers are used?
- lower body via posterior spinocerebellar fibers
- upper body via cuneocerebellar fibers
- head via vestibulocerebellar fibers
describe the path of afferent fibers in the inferior cerebellar peduncles from the lower body
lower body movement triggers a signal to the spinal cord dorsal nucleus of clark which then travels along the pscf to the cerebellar cortex
describe the path of afferent fibers in the inferior cerebellar peduncles from the upper body
upper body movement triggers a signal to the brainstem lateral cuneate nucleus which then travels along the cuneocerebellar fibers to the cerebellar cortex
describe the path of afferent fibers in the inferior cerebellar peduncles from the inner ear (head)
the inner ear sends a signal to the brainstem vestibular nuclei which then travels along the vestibulocerebellar fibers to the cerebellar cortex
describe the path of afferent fibers in the middle cerebellar peduncles from the motor cortex
motor cortex sends a signal via corticopontine fibers to the pontine nuclei, which is relayed to the cerebellar cortex via pontocerebellar fibers
middle cerebellar peduncles convey (afferent or efferent) fibers carrying (motor or sensory) signals to cerebellum.
afferent, motor
where do the afferent fibers in the middle cerebellar peduncles convey information from and which fibers are used?
from motor cortex, via pontine nuclei and utilizes corticopontine and pontocerebellar fibers
how are the layers of the cerebellar cortex organized? what is each made out of?
- layers 1-3 are gray matter
- layer 4 is white matter
- layer 2 is make of purkinje cells
the purkinje cell layer in the cerebellar cortex provide what kind of feedback? What are they targeting?
- inhibition
- deep-nuclei neurons
Purkinje cell bodies use which inhibitory neurotransmitter ?
GABA
the purkinje cell layer of the cerebellar cortex are regulated by which 4 tracts? What kind of fibers do they use (afferent/efferent)
ALL AFFERENT FIBERS from:
- spinocerebellar tract
- cuneocerebellar tract
- vestibulocerebellar tract
- pontocerebellar tract
purkinje cell bodies project GABAergic fibers to which layer? This inhibitory projection regulates what?
- cerebellar white matter layer 4
- glutamatergic deep nuclei neurons
afferent fibers have cell bodies in what locations and what neurotransmitter is in charge of exciting them?
- brainstem and spinal cord
- glutamate
deep-nuclei neurons in the cerebellum integrate ___1.____ and __2.___ signals to regulate __3.__ and __4.___ systems
1/2 - sensory and motor
3/4 -lateral and medial descending motor
what are the three deep nuclei neurons in the cerebellum and what specific anatomical subdivisions do they correspond with?
- dentate nucleus - lateral hemisphere
- interposed nucleus - paravermis
- fastigial nucleus - vermis
the interposed nucleus neurons in the paravermis integrate what kinds of signals? what do those signals regulate?
- sensory signals
- regulate adjustments of ongoing voluntary movements of the extremities in lateral descending motor systems
the dentate nucleus neurons in the lateral cerebellar hemisphere integrate what kind of signals? What do those signals regulate?
- motor signals
- regulate movement timing and direction in lateral and medial descending motor systems
the fastigial nucleus neurons in the vermis integrate what kind of signals? What two things do those signals regulate?
- sensory signals
- regulate adjustments of ongoing voluntary movements of the trunk in medial descending motor systems and head position & balance/postural control in medial and lateral descending motor systems
a patient comes into the hospital presenting symptoms of dysmetria when performing the finger to nose test and dysdiadochokinesia during the forearm pronation-supination test. What diagnosis would you give them? Where would the potential damage be?
DIAGNOSIS: neocerebellar syndrome
CAUSES: damage to purkinje cells in lateral cerebellar cortex/hemisphere and/or dentate nucleus neurons or vascular lesion/stroke of PICA
neocerebellar syndrome affects coordination of (contralateral/ipsilateral) voluntary movements.
ipsilateral
a vascular lesion/stroke of the PICA would result in which of the following:
a) neocerebellar syndrome
b) anterior lobe syndrome
c) flocculonodular lobe lesion
d) vertigo
a) neocerebellar syndrome
a vascular lesion/stroke of the superior cerebellar arteries would result in which of the following:
a) neocerebellar syndrome
b) anterior lobe syndrome
c) flocculonodular lobe lesion
d) dysmetria
b) anterior lobe syndrome
a vascular lesion/stroke of the AICA would result in which of the following:
a) neocerebellar syndrome
b) anterior lobe syndrome
c) flocculonodular lobe lesion
d) dysdiadochokinesia
c) flocculonodular lobe lesion
a patient who has a history of alcoholism comes into the ER presenting bilateral deficits in lower trunk and leg muscles. When performing the heel-to-shin test, they present abnormal movements. Where might the damage be and what would be the diagnosis?
CAUSES: loss of purkinje cells in rostral vermis or vascular lesion/stroke to superior cerebellar arteries
DIAGNOSIS: anterior lobe syndrome
a patient comes into the ER presenting symptoms of incoordination of back extensor muscles, vertigo, nystagmus but has a normal heel-to-shin test. What diagnosis would this be and where would the potential damage be?
CAUSES: vascular lesion/stroke to AICA or damage to purkinje cells in flocculonodular lobe
DIAGNOSIS: flocculonodular lobe lesion
a patient diagnoses with a cerebellar tumor in the right lateral cerebellar hemisphere may exhibit which of the following clinical symptoms?
a) resting tremor on the right side
b) difficulty in keeping his balance
c) dysdiadochokinesia in left upper limb
d) dysmetria in right upper limb
d) dysmetria in right upper limb
