Blumenfeld Ch 12 Cerebellum

Front 1

name 3 functional zones of cerebellum

Back 1

1. vermis and flocculonodar lobes
2. intermediate part
3. lateral part

Front 2

role of vermis and flocculonodular lobes

Back 2

important for control of proximal and trunk muscles and in vestibulo-occular control, respectively. vermis output is thru fastigial nuclei and flocculondular lobe output is thru vestibular nuclei.

Front 3

role of intermediate part of cerebellum

Back 3

control of more distal muscles in arms and legs. output thru interposed nuclei.

Front 4

role of lateral cerebellum

Back 4

largest part of cerebellum, involved in planning motor programming for extremeties. output via dentate nuclei.

Front 5

excitatory synaptic inputs to cerebellum

Back 5

mossy fibers and climbing fibers. mossy fibers synapse with granule cells, which form parallel fibers and synapse onto Purkinje cells. climbing fibers synpase onto Purkinje cells 1 climbing fiber-> 10 Purkinje cells

Front 6

deficits in coordination occur (contralateral or ipsilateral) to cerebellar lesion

Back 6

ipsilateral

Front 7

why are deficits ipsilateral to lesion in cerebellum

Back 7

patways from cerebellum are double-crossed. first crossing as cerebellar output exit in decussation of superior cerebellar peduncle and second crossing at corticopspinal and rubrospinal tracts descend to SC (i.e., pyramidal and ventral tegmental decussation, respectively). vermis lesions have b/l effects

Front 8

origins of inputs to cerebellum

Back 8

cerebral cortex (all 4 lobes), arm and leg proprioceptors and interneurons, red nucleus, BS, SC, vestibular system

Front 9

vascular territories:
posterior inferior cerebellar artery (PICA)

Back 9

supplies lateral medulla, most of inferior half of cerebellum and inferior vermis

Front 10

vascular territories:
anterior inferior cerebellar artery (AICA)

Back 10

inferior lateral pons, middle cerebellar epduncle, and a strip of ventral (anterior) cerebellum b/w territories of PICA and SCA, including flocculus

Front 11

vascular territories:
superior cerebellar artery (SCA)

Back 11

supplies upper lateral pons, superior cerebellar peduncle, most of superior half of cerebellar hemisphere including deep cerebellar nuclei and superior vermis

Front 12

sxs of cerebellar infarcts

Back 12

vertigo, nausea, vomiting, horizontal nystaagmus, limb ataxia, slurred speech, unsteady gait and h/a.

Front 13

"ataxia"

Back 13

means "lack of order" referring to disordered contractions of agonist and antagonist muscles and lack of normal coordination b/w movements at different joints.

Front 14

truncal ataxia

Back 14

wide-based, unsteady, drunken gait. medial motor system is impaired and this occurs with lesions to the vermis.

Front 15

appedicular ataxia

Back 15

lesions to lateral or intermediate cerebellum affect lateral motor systems, ataxia of extremities.

Front 16

other causes of ataxia

Back 16

lesions to cerebral peduncels or pns, hydrocephalus, prefrontal cortex lesions, SC disorders

Front 17

ataxia-hemiparesis

Back 17

syndrome caused by lacunar infarcts, combination of unilateral UMN signs and ataxia. both ataxia and hemiparesis are contralateral to lesion

Front 18

sensory ataxia

Back 18

posterior column-medial lemniscal pathway lesion; loss of joint position sense. may overshoot limbs and wide-based unsteady gait. unlike cerebellar lesions, will have impaired joint sense on exam. can be improved with sensory feedback and is worse w/ eyes closed. lesions to peripheral nerves orposterior column and st thalamus or somatosensory cortex lesions

Front 19

speech abnormalities

Back 19

explosive or scanning speech- irregular fluctuations in rate and volume. can be slurred or difficult to understand.

Front 20

disdiadochokinesia

Back 20

abnormalities of rapid alternating movement

Front 21

eye mvmt abnormalities

Back 21

occular dysmetria (overshoot or undershoot target), jerky saccades, nystagmus