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Jason's Neuro Block > Eye Movements > Flashcards

Flashcards in Eye Movements Deck (22)
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1
Q

what are the two components to stabilize image on retina?

A
  1. occulomotor system: eye in socket

head movement system: socket as whole with vestibular system

2
Q

Saccades does what to image?

A

shift fovea rapidly to new target

3
Q

what does smooth pursuit do?

A

keeps image of moving target on fovea

4
Q

what does optokinetic movements do?

A

holds image still during sustained head rotation

5
Q

6 extraocular muscles:

A

Superior Rectus
Inferior Rectus
Medial Rectus
Lateral Rectus

Inferior Oblique
superior Oblique

6
Q

Superior oblique movements?

A

torsion and depression adduction

7
Q

inferior oblique movements?

A

torsion and elevation

8
Q

Superior Oblique muscles innervated by?

A

trochlear: CNIV

9
Q

Lateral Rectus muscle innervated by?

A

Abducens: CN VI

10
Q

trochlear CN IV innervates which superior oblique?

A

the CONTRALATERAL one…

11
Q

what connects white matter tracts between cranial nerve nuclei?

A

medial longitudinal fasciculus (MLF)

12
Q

what reticular formation in the pons for coordinated eye movements?

A

pontine paramedian reticular formation

13
Q

what reticular formation in the midbrain for coordinated eye movements?

A

mesencephalic paramedian reticular formation

14
Q

What does Pontine RF coordinate? which nerves?

A

horizontal gaze

(MR)CN III and (LR)CNVI

15
Q

what does midbrain RF coordinate?

A

vertical gaze

(SO) CN IV and (SR)CN III

16
Q

two kinds of neurons fire during horizontal saccades?

A

burst neurons before movement

omnipause neurons fire when eye not moving

17
Q

Omnipause neurons do what?

A

inhibit via GABA

18
Q

Burst neurons do what kind of signalling?

A

excitatory for ipsilateral abducens

inhibitory for contralateral abducens

19
Q

what do you need for neural control of saccades?

A

simultaneous burst and inhibition of omnipause

20
Q

eye movements ultimately driven by?

A

behaviour

21
Q

what drives brainstem gaze centres? 5 things

A
frontal eye fields
post parietal cortex
superior colliculus
basal ganglia
cerebellum
22
Q

which nerves needed coordinates head and eye movements together?

A

vestibulocochlear to medulla nuclei with CNIII, CNVI nuclei