Control of Eye Movements Flashcards Preview

Hugh's MD1 Neuro > Control of Eye Movements > Flashcards

Flashcards in Control of Eye Movements Deck (23):
1

What does in the medial longitudinal fasciculus do in horizontal gaze?

It is a white matter tract that connects various cranial nerve nuclei

1

When do omnipause neurons fire? What is their main role?

Continuously during the saccade

Tell the eyes to stop moving

2

What are the two types of neurons in the pontine paramedian reticular formation?

Burst neurons and omnipause neurons

2

Where in the cortex controls saccades?

Frontal eye fields

Posterior parietal cortex

3

What is the primary action of the superior rectus?

Elevation

3

Which oculomotor motor muscle in innervated by the abducens nerve?

LR

3

What do burst neurons do?

Fire at high frequency just before movement

5

What are optokinetic eye movements?

Holds an image stationery during sustained head rotation or translation

6

Which rectus muscle muscle do the obliques insert near to?

The lateral rectus

7

What muscles are involved in horizontal gaze?

MR and LR

9

What type of eye movement is intorsion?

Rolling upwards and medially

9

Do the oblique muscles insert behind or infront of the equator?

Behind

9

How does the vestibular system sense head movement?

Fluid moving across hair bundles in the ampulla of the inner ear

10

What are saccadic eye movements?

Rapid shifting of the fovea over a new visual target - eg looking at a painting

12

What is smooth pursuit eye movement?

Keeps the image of a moving target on the fovea

13

Where in the information from the vestibular system integrated with control of horizontal gaze?

Vestibular nuclei in the medulla

15

What are the two components of control of gaze?

Oculomotor system - Moves eyes in the orbit

 

Head-movement system - Moves the eye sockets as a whole

17

T/F When adducted only the superior oblique can depress

True

19

Which part of the reticular formation is important in control of horizontal gaze?

The pontine paramedian reticular formation

20

What must occur in burst and omnipause neurons for eye movement?

Simultaneous excitation of burst neurons and inhibition of omnipause neurons

21

Which system comes into play when coordinating head and eye movements?

The vestibular

22

T/F When abducted, only the inferior oblique can elevate

False, the superior rectus elevates when abducted

23

T/F the Abducens innervates the contralateral eye

False the trochlear does