Cerebellar Dysfunction

Question 1

To which side of the body does the cerebellum sends information? (Ipsi or contralateral)

Answer 1

ipsilateral

Question 2

What are the functional division of the Cerebellum?

Answer 2

1. Vestibulocerebellum
2. Spinocerebellum
3. Cerebrocerebellum

Question 3

Which lobe contains the vestibulocerebellum?

Answer 3

flocculonodular lobe

Question 4

Vestibulocerebellum input from and output to?

Answer 4

Input

vestibular nuclei

CN8

output

Vestibular nuclei

lateral vestibular spinal tract

Question 5

Function of the vestibulocerebellum

Answer 5

Integrates vestibular information and dictates motor control of neck and eye muscle

Allow to keep eye stable while head moves (gaze stabilization) & keep head over BOS

Control Gait and postural control

Question 6

Injuries to the vestibulocerebellum can lead to….

Answer 6

ataxic gait (path deviation TOWARD the side of the lesion)

inability to stabilize gait

deficit in postural control

Question 7

Which zone contains the spinocerebellum?

Answer 7

vermis

intermediate

Question 8

input and output of the spinocerebellum

Answer 8

Input

spinal cord: Dorsal spinocerebellar tract & Vestibulocerebellar tract

Output

Vestibular nuclei

red nucleus

reticular formation

Question 9

Function of the Dorsal spinocerebellar tract (DSCT)

Answer 9

sensory info from organ GTO, sensory, proprioception

Question 10

Function of the ventral spinocerebellar tract (VSCT)

Answer 10

sensory from LE & Postural control

Question 11

Function of the spinocerebellum

Answer 11

Integrates information from all decending motor tracts (VSCT)

real time information to be more successful with an intent action

Question 12

location of the cerebrocerebellum

Answer 12

cerebellar hemispheres

Question 13

input/output of the cerebrocerebellum

Answer 13

input:

deep pontine nuclei

output

thalamus

Question 14

Function of the cerebrocerebellum

Answer 14

indirect information from all 4 cortical lobes

• Areas 6,4,3,1,2,5
• Primary visual cortext (17)

Question 15

Lesions of the Cerebellum will lead to what types of deficits?

Answer 15

Impaired ability to perform controlled, precise, coordinated movements

must be large enough for symptoms to appear

hypotonia of MSRs (pendular reflex)

NO PARALYSIS and WEAKNESS (usually)

Question 16

Function of Cerebellum in Movement

Answer 16

A regulator

feedback and feed-forward conrol ssytem

Question 17

Cerebellum input/output

Answer 17

input:

information about body position and muscle action

output:

to descending motor systems at the brainstem level

Question 18

Role of spinocerebellum in movement

Answer 18

output occurs while motion is occuring

the state of the motion, drives the next command fromt he cerebellum

Question 19

Role of Cerebrocerebellum in movement

Answer 19

feed-forward

receives infromation from PMA, SMA< and primary motor and sensory areas

modify the action before it takes place

Theory: manages the model of control system

Question 20

Hallmark signs of Cerebellar Dysfunction

Answer 20

1. Ataxia (limb movement, trunkal, gait)
2. Nystagmus
3. Dysmetria
4. dysdiadochokinesia
5. Decomposition of movement ipsilateral to leasion

Question 21

Clinical Presentation of Vestibulocerebellar injury

Answer 21

Mimics disease in vestibular nuclei or PVS

Ataxic gait (fall toward side of lesion, inadequate postural correction)

Nystagmus

Vertigo/dizziness

Question 22

What is nystagmus

Answer 22

oscillating eye movement in which eyes move slow in one direction and rapidly in the other direction

Question 23

Features of Gait Ataxia

Answer 23

High stepping

stagger to the side of lesion

irregular foot placement

irregular timing

patient use decomposition of complex movements to control incoordination which results in robotic look

Question 24

Clinical Presentation of Spinocerebellar and Cerebrocerebellar injury

Answer 24

impairment in precision of movement

Dysdiadochokinesia

Dysmetria

decomposition of movement

pendular muscle stretch reflex

hypotonia (limb feel heavy)

Question 25

Dysdiadochokinesia

Answer 25

disruption in timing of muscle difficulty with Rapid alternating movement (RAM)

Question 26

Dysmetria

Answer 26

Performance deterioration as motor act progresses

Question 27

What test can be used to test for dysmetria?

Answer 27

finger to nose test

Question 28

Dysmetria vs. Tremor

Answer 28

Dysmetria: form of incoordination secondary to cerebellar dysfunction. Performance deteriorates as target is approached (cerebellar injury) Tremor: rhythmic movement at constant frequency and amplitude. Result of continuous oscillatory beavior in central motor areas (e.g. Parkinson)

Question 29

What is decomposition of movements?

Answer 29

poor timing of motor acts normal synergistic movement of complex motor tasks is broken down and initiated separately difficulty with sequencing repetitive task ataxia

Question 30

Role of Cerebellar in motor learning

Answer 30

modification of function in relation to experience e.g. riding a bike transfer of motor tactics from conscious to unconscious Adaptive feedforward control system Internal stored model controls learned movement

Question 31

with cerebellar lesions, movement must use ______ and thus producing uncoordinated movements

Answer 31

slow sensory feedback loops

Question 32

Theory of motor learning & cerebellum

Answer 32

Theory I: CB learns small simple programs, facilitates triggering of small programs, in order, for complex motor tasks, recognizes and detects event sequences Theory II: CB role in adaptation, anticipatory ms activity across several joints, modification activity Theory III: CB influence not purely motor, role in mental imagery/practice, role in rapid shifts of attention

Question 33

Examination of Cerebellum should include

Answer 33

1. RAM 2. gait 3. dysmetria 4. decomposition 5. VOR 6. change of symptoms with position changes

Question 34

Consideration when tx patient with CB injury

Answer 34

1. Postural control 2. Motor Learning (need more attention) 3. Attention (problem with switching task) 4. Motor control (less automatic) 5. Functional tasks Get tired very easily: block practice decrease distraction/obstacles 1 feedback at at time concurrent tactile feedback, auditory feedback att he end

Question 35

Ways to work on Dysmetria

Answer 35

Temporary reduction techniques * as primer for functional tasks * PNF * full body movements * T-band * Frenkel exercises (Progressive exercises for ataxia and coordiantion * Wt to dampen ataxia (use proximal not distal)

Question 36

Intervention for ataxic gait

Answer 36

Encourage stiffening of joints (ankle) practice setup part to whole frequent feedback use of device (walker tends to get far away, encourage small steps)

Question 37

There is an increase firing of what structure during acquisition of complex motor task?

Answer 37

Cerebellum

Question 38

Effect of Visual-vestibular dysfunction

Answer 38

Diplopia impact on function (decrease attention on sx) Use of visual exercises (smooth pursuit, saccades, VOR) habituation exercises (full body position changes to get used and not get dizzy)

Question 39

+ Prognosis of CB injury recovery

Answer 39

spared cerebral cortex unilateral injury degenerative disease vs acute injury

Question 40

- prognosis of CB injury

Answer 40

bilateral injury damage to deep CB nuclei damage to others aspects of brain concomitant abuse of alcohol