Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Z YEAR 2 BRS NEURO > Visual System Eye movements > Flashcards

Visual System Eye movements Flashcards

1
Q

How is voluntary or involuntary movement of eyes done?

A

Facilitated by the six extraocular muscles innervated by the three cranial nerves (III, IV and VI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why is eye movement important?

A

helps to acquire and track visual stimuli.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is duction?

A

Eye Movement in One Eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is version?

A

Simultaneous movement of both eyes in the same direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is vergence?

A

Simultaneous movement of both eyes in the opposite direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is convergence?

A

Simultaneous adduction (inward) movement in both eyes when viewing a near object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is gazing to the left?

A

Levoversion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is gazing to the right?

A

Dextroversion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is saccade eye movement?

A

short fast burst, up to 900°/sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are different types of saccade?

A 
•Reflexive saccade to external stimuli
•Scanning saccade
•Predictive saccade to track objects
•Memory-guided saccade
-Can be voluntary or involuntary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is smooth pursuit?

A

sustain slow movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are types of smooth pursuit?

A

•Slow movement – up to 60°/s
•Driven by motion of a moving target across the retina.
-Involuntary for moving target

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the 4 straight extra ocular muscles?

A
  1. Superior rectus
    2 .Inferior rectus
  2. Lateral rectus
  3. Medial rectus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where do 5 out of the 6 muscles come out from?

A

Cone from back of orbit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does the inferior oblique come in?

A

nasally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where is the superior rectus attached to the eye?

A

at 12 o’clock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does the superior rectus do?

A

Moves eye up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where is the inferior rectus attached to the eye?

A

at 6 o’clock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does the inferior rectus do?

A

Moves eye down

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What do vertical rectus muscles to?

A

attach anterior to the globe equator,

and pull backwards and nasally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens when the eye is in an adducted position?

A

the anterior-posterior axis of the eye is not aligned with the vertical rectus muscle action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What happens when the eye is in an abducted position?

A

the anterior-posterior axis of the eye is aligned with the insertion of the vertical rectus muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What do the superior and inferior rectus to when the eye is in an abducted position?

A
  1. Superior Rectus muscle: elevates the eye maximally

2. Inferior Rectus muscle: depresses the eye maximally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do vertical rectus muscles do when the eye is in an adducted position?

A

Vertical rectus muscles produce torsion motion instead

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Where does the lateral rectus attach?

A

temporal side of the eye

26
Q

What does the lateral rectus do?

A

Moves the eye toward the outside of the head (toward the temple)

27
Q

Where is the medial rectus attached?

A

nasal side of the eye

28
Q

What does the medial rectus do?

A

Moves the eye toward the middle of the head (toward the nose)

29
Q

Where is the superior oblique attached?

A
  • Attached high on the temporal side of the eye

- Passes under the Superior Rectus

30
Q

What does the superior oblique do?

A

Moves the eye in a diagonal pattern down and out

31
Q

What does the superior oblique travel through?

A

trochlea

32
Q

Where is the inferior oblique attached?

A
  • Attached low on the nasal side of the eye.

- Passes over the Inferior Rectus

33
Q

What does the inferior oblique do?

A

Moves the eye in a diagonal pattern - up and out

34
Q

What does the superior branch of the oculomotor nerve (III) innervate?

A
  1. Superior Rectus – elevates eye

2. levator palpebrae superioris - raises eyelid (not shown)

35
Q

What does the inferior branch of the oculomotor nerve (III) innervate?

A
  1. Inferior Rectus – depresses eye
  2. Medial Rectus – adducts eye
  3. Inferior Oblique – elevates eye
  4. Parasympathetic Nerve – constricts pupil
36
Q

What does the trochlear (IV) nerve innervate?

A

Superior Oblique – depresses eye

37
Q

What does the abducens (VI) nerve innervate?

A

Lateral Rectus – abducts eye

38
Q

How do you test extra ocular muscles?

A

Isolate muscle to be tested by maximizing its action and minimizing the action of other muscles

39
Q

In what position is the lateral rectus action best tested?

A

abduction

40
Q

In what position is the medial rectus action best tested?

A

adduction

41
Q

In what position is the superior rectus action best tested?

A

elevated and abducted

42
Q

In what position is the inferior rectus action best tested?

A

depressed and abducted

43
Q

In what position is the inferior oblique action best tested?

A

elevated and adducted

44
Q

In what position is the superior oblique action best tested?

A

depressed and adducted

45
Q

What is supraversion and supraduction?

A

Elevation:
Supraduction – one eye
Supraversion – both eyes

46
Q

What is infraversion and infraduction?

A

Depression (down):
Infraduction – one eye
Infraversion – both eyes

47
Q

What is abduction?

A

refers to duction movement of one eye,

moving away from the nose

48
Q

What is adduction?

A

refers to duction movement of one eye,

moving towards the nose

49
Q

What is dextroversion?

A

involves simultaneous right eye abduction,

and left eye adduction

50
Q

What is levoversion?

A

involves simultaneous left eye abduction,

and right eye adduction

51
Q

What is third nerve palsy signs?

A
  1. Affected eye goes down and out
  2. Droopy eyelid (loss of elevator palpebrae superioris as innervated by superior branch of occuolomotor nerve)
  3. Unopposed superior oblique innervated by fourth nerve (down)
  4. Unopposed lateral rectus action innervated by sixth nerve (out)
52
Q

What happens in complete third nerve palsy?

A

-only muscles not innervated by the third cranial nerve in the affected eye are working
-lateral rectus muscle, responsible for abduction,
and superior oblique muscle, responsible for depression
-causes over-action of the two unopposed muscles,
and the affected eye adopts a down and out position

53
Q

What is sixth nerve palsy?

A
  1. Affected eye unable to abduct and deviates inwards

2. Double vision worsen on gazing to the side of the affected eye

54
Q

What is the deficit in sixth nerve palsy?

A

deficit in abduction in the affected eye, affected eye deviates inward

55
Q

What is nystagmus?

A

Oscillatory eye movement

56
Q

What is Optokinetic Nystagmus?

A

Smooth Pursuit + Fast Phase Reset Saccade

57
Q

When is Optokinetic Nystagmus Reflex useful?

A

in testing visual acuity in pre-verbal children by observing the presence of nystagmus movement in response to moving grating patterns of various spatial frequencies

58
Q

What does Presence of Optokinetic Nystagmus in response to moving grating show?

A

that the subject has sufficient visual acuity to perceive the grating pattern

59
Q

What is torsion?

A

rotation of eye around the anterior-posterior axis of the eye

60
Q

Is it possible to have 4th nerve palsy?

A

Yes

Z YEAR 2 BRS NEURO (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions