week 5- cerebellum

Question 1

link the deep nuclei with their function

Answer 1

Dentate-planning/timing/skill - lateral hemisphere

Globose & Emboliform-posture/ muscle tone/ walking- paravermis

Fastigial-eye movement & balance- vermis

Question 2

what is the function of the granule cells

Answer 2

Excitatory: GLU

cell body in the granule layer

Input from: mossy fibers

Input to: purkinje cell dendrites via parralel fibers

Question 3

what is the function of pyramidal cells

Answer 3

Inhibitory: GABA

Cell body in the purkinje layer, dendrites in the cerebellar cortex, axons go to deep nuclei

Input from: granule cells & climbing fibers

Input to: deep nuclei

Question 4

what are the climbing and mossy fibers

Answer 4

Climbing fibers : Axons from ION of medulla To purkinje cells. they are excitatory

Mossy fibers: Axons from all other brainstem nuclei

To granule cells

Question 5

what is the functin of golgi and basket cells

Answer 5

GOLGI: excitatory synaptic inputs from mossy fibers and parallel fibers, and their axons make inhibitory synapses with granule cells

Basket:

Question 6

name the inputs into the cerebellum

Answer 6

input through the middle and inferior peduncle

Question 7

what are the output paths from the cerebellum

Answer 7

output through the superior and the inferior peduncle

Question 8

what does the ION allow

Answer 8

important inadaptation of motor output to changing situation) via climbing fibers.

Question 9

what are the excitatory and inhibitory cells in the cerebellum

Answer 9

excitatory-

granule cells, mossy fibers, climbing fibers

inhibitory-

purkinje cells, golgi cells, basket cells

Question 10

what is the function of the

vermis

paravermis

lateral hemisphere

Answer 10

vermis- balance (important to gait)

paravermis- limb coordination

lateral hemisphere- planning and exucuding of coordinate movements

Question 11

what lobe contains the tonsils

Answer 11

posterior lobe

*tonsillar herniation just above the foramen magnum –> compression of medulla –> dec respiration.

LP in this PT = death

Question 12

what is the function of the flocculonodular lobe

Answer 12

VOR

Question 13

what is in the Vestibulocerebellum and what is it responsible for

Answer 13

Contains: flocculonodular lobes(vestibular nuclei) + posterior vermis (fastigial nucleus)

Function: control of eye movements, including VOR + balance and equilibrium

Damage: problems with eye movements (smooth pursuit) + balance difficulty

Question 14

what is in the Spinocerebellum and what is it responsible for

Answer 14

Contains: anterior lobe+ anterior vermis (fastigial nucleus) + paravermian cortex (globose & emboliform nuclei)

Function: Control of axial musculature(posture/muscle tone) + coordination of movement of trunk and limbs (walking)

Damage: gait atazia, wide stance

Question 15

what is in the Cerebrocerebellum/pontocerebellum and what is it responsible for

Answer 15

Contains: Lateral hemispheres (lateral portion of posterior lobe– dentate nucleus)

Function: planning phases and timing of fine, skilled, cortically initiated movements

Question 16

what does a Unilateral lesions of cerebellar hemisphere/peduncles results in

Answer 16

ipsilateral movement disorder

Question 17

what are signs of cerebellar damage

Answer 17

Dysmetria, dysdiadochokinesia, dysarthria, dysrhythmia , decomposition

Ataxia

Nystagmus

Intention tremor

Scanning speech

Hyoptonia

pedular reflex

Question 18

what would you suspect with gait ataxia without limb ataxia

Answer 18

alcoholic degeneration of the superior anterior vermis

Question 19

define Dysdiadochokinesia

Dysmetria

Decompositionof movements

Answer 19

inability to rapid, alternating movements, ie an expression of dysrhythmia

May overshoot target (“past-pointing”) or undershoot

during planned motor activity (ie reaching for target).

Test: touch finger to nose then to extended hands of examiner