B7.043 Prework: Cerebellar Systems

Question 1

function of the cerebellar system

Answer 1

corrections of motor systems
modulate outputs of direct motor pathways
no direct motor outputs
modulation via the thalamus and other nuclei

Question 2

lateral hemispheres of cerebellum

Answer 2

function: motor planning
deep nuclei: dentate
input: corticopontine
output: superior cerebellar peduncle to thalamus
motor pathways influenced: lateral corticospinal

Question 3

intermediate hemispheres of cerebellum

Answer 3

function: ongoing distal limb movement
deep nuclei: emboliform and globose
input: spinocerebellar
output: superior cerebellar peduncle to red nucleus to thalamus
motor pathways influenced: lateral corticospinal, rubrospinal

Question 4

vermis

Answer 4

function: truncal balance
deep nuclei: fastigial
input: spinocerebellar and vestibular
output: vestibular nuclei
motor pathways influenced: medial motor pathways (anterior, corticospinal, *vestibulospinal*, reticulospinal)

Question 5

flocculonodular cerebellum

Answer 5

function: eye movement
input: vestibular nuclei
output: vestibular nuclei
motor pathways influenced: medial longitudinal fasiculus

Question 6

symptoms of flocculonodular dysfunction

Answer 6

vertigo

nausea, vomiting

Question 7

symptoms of vermal system dysfunction

Answer 7

unable to stand or sit (tilt towards affected side)

dysarthria

Question 8

symptoms of lateral and intermediate system dysfunction

Answer 8

limb clumsiness

inability to perform tasks (button clothes)

Question 9

ataxia

Answer 9

lack of order

Question 10

dysmetria

Answer 10

abnormal undershoot or overshoot (inaccuracy)

decomposition of movement into parts

Question 11

test for dysmetria

Answer 11

finger to nose to finger

heel to shin

Question 12

dysrhythmia

Answer 12

abnormal timing of movements

Question 13

testing for dysrhythmia

Answer 13

finger tapping

Question 14

dysdiadochokinesis

Answer 14

inability to make rapid, alternating movements

Question 15

abnormal check

Answer 15

exaggerated recovery phase from movement

“rebound”

Question 16

how to test abnormal check

Answer 16

tasks requiring a sudden stop

Question 17

types of cerebellar tremors

Answer 17

postural

intention

Question 18

postural tremor

Answer 18

irregular, large amplitude tremors when muscles activated to maintain a posture (outstretched arms)
when very high amplitude

Question 19

intention tremor

Answer 19

dysmetria worsening when limb approaches a target

Question 20

tests for truncal ataxia (vermal system)

Answer 20

can the patient sit or stand with eyes open?
wide based gait
scanning speech

Question 21

relationship between vision and cerebellar dysfunction

Answer 21

does not impact
cerebellar dysfunction would cause lack of balance with or without visual input
SENSORY loss is dependent on visual input (Romberg test)

Question 22

eye movements associated with flocculonodular system dysfunction

Answer 22

nystagmus

• direction changing
• gaze evokes

Question 23

most common etiology of cerebellar system dysfunction

Answer 23

diffuse metabolic processes affecting the nervous system

Question 24

how to localize lesions with cerebellar symptoms

Answer 24

rely on other affected systems

Question 25

is no other systems are affected…where is a cerebellar lesion?

Answer 25

ipsilateral cerebellum

Question 26

symptoms and signs of unilateral lateral cerebellar dysfunction

Answer 26

minimal