Case 7 - Cerebellum and control of movement

Question 1

what do lower motor neurones (spinal cord and brainstem) innervate

Answer 1

skeletal muscle

Question 2

what do upper motor neurones innervate (cerebral cortex and brainstem)

Answer 2

control lower motor neurones

Question 3

features of alpha Lower motor neurones

Answer 3

innervate extrafusual muscle fibres - give muscle its strength

Question 4

what do gamma motor neurones innervate

Answer 4

intrafusual muscle fibres - stretch receptors

Question 5

what do lower motor neurones mediate (reflexes)

Answer 5

stretch reflex (monosynaptic reflex from stretch receptors to alpha motor neurones)

gamma reflex (controls sensitivity of stretch reflex)

Question 6

what do lower motor neurone lesions result in

Answer 6

paralysis
loss of tendon reflexes
hypotonia, wasting, fasciculation
motor neurone disease, polio, peripheral nerve injury
symptoms are ipsilateral

Question 7

stretch reflex and gamma reflex diagram

Question 8

what type of pathways are upper motor neurones

Answer 8

descending pathways

Question 9

what influences alpha and gamma motor neurones via these descending tracts

Answer 9

brainstem nuclei (vestibular, reticular, red nuclei)

Question 10

what do these descending pathways control

Answer 10

control reflexes, tone and posture

Question 11

what do brainstem nuclei excite

Answer 11

excite gamma motor neurones. brainstem nuclei are inhibited by cerebral cortical efferents (not completely true just a posited theory)

Question 12

what are the two tracts of upper motto neurones

Answer 12

corticospinal and corticobulbar

Question 13

what is another name for corticospinal tract

Answer 13

pyramidal

Question 14

what do these two tracts control

Answer 14

fine skilled movements

Question 15

corticospinal and corticobulbar tracts diagram

Answer 15

Question 16

what do upper motor neurone lesions cause

Answer 16

paralysis and positive Babinski reflex due to corticospinal tract damage

hypertonia and hyperreflexia due to loss of cortical inhibition of brainstem nuclei

paralysis, hypereflexia and hypertonia are referred to as spasticity

symptoms are contralateral

Question 17

the basal ganglia diagram

Answer 17

Question 18

what does the cerebellum do

Answer 18

coordinates balance and movement
concerned with which muscles need to be activated to achieve a particular movement
integrates information from the cerebral cortex (via pons) and peripheral sense organs
sends output to brainstem nuclei and cerebral cortex (via thalamus)

Question 19

diagram of the cerebellar peduncles

Answer 19

Question 20

what is there cerebellum connected to other structures by

Answer 20

3 sets of nerve fibres called cerebellar peduncles

Question 21

what connects the cerebellum to the medulla

Answer 21

inferior cerebellar peduncle

Question 22

what connects the cerebellum to the pons

Answer 22

middle cerebellar peduncle

Question 23

what connects the cerebellum to the midbrain

Answer 23

the superior cerebellar peduncle

Question 24

what is the paleocerebellum particularly connected with q

Answer 24

the spinocerebellar tract - afferents to the cerebellum from the periphery

Question 25

what is the largest part of the functional divisions of the cerebellum

Answer 25

the neocerebellum is the largest part and is paeticualry connected to the cerebral cortex via a relay or a connection in the pons

Question 26

diagram showing the functional divisions of the cerebellum

Answer 26

Question 27

what are the deep cerebellar nuclei

Answer 27

Question 28

what is the input into the cerebellum

Answer 28

spinocerebellar tracts
vestibular nuclei
cerebral cortex

Question 29

where is the vestibular nuclei located

Answer 29

in the medulla oblongata in the brainstem and go trough the medulla at the level of the interior olivary nucleus

Question 30

what is input by the cerebral cortex via

Answer 30

pontine nuclei that are scattered throughout the tegmentum

Question 31

where is the output of the cerebellum from and to

Answer 31

from deep cerebellar nuclei
to brainstem and thalamus

Question 32

where does the purkinje layer lie

Answer 32

between the molecular layer and the granular layer in the cerebral cortex

Question 33

where does input to the archiceebellum come from

Answer 33

input comes from the vestibular nerve and to the vestibular nuclei and from there via the inferior peduncle cells project into the cerebellar cortex

Question 34

where do purkinje cells project to

Answer 34

the gastigial nucleus and the gastigial nucleus happens to project back to the vestibular nuclei and it also projects to the reticular nuclei of the brainstem and both of these have connections to the spinal cord

Question 35

what is the output of purkinje cells to

Answer 35

the deep cerebellar nuclei

Question 36

connections of the paleocerebellum diagrams

Answer 36

Question 37

connections and pathways of the neocerebellum diagram

Answer 37

Question 38

what is the result of a lesion in the cerebellar midline

Answer 38

loss of postural control and balance

Question 39

what happens if there is a unilateral hemisphere lesion in the cerebellum

Answer 39

incoordination of arm and leg causing unsteady gait. symptoms usually occur ipsilaterally

Question 40

what happens if there is a bilateral hemisphere lesion in the cerebellum

Answer 40

slow, scanning speech; incoordination of limbs and staggering gait

Question 41

what is neuroleptic malignant syndrome

Answer 41

Neuroleptic malignant syndrome (NMS) is a life-threatening neurologic emergency associated with the use of antipsychotic (neuroleptic) agents and characterized by a distinctive clinical syndrome of mental status change, rigidity, fever, and dysautonomia.

look up more about this as it may be