Brainscape's Knowledge GenomeTM

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


See full index

Vision Science 2 > 3 - Visual Direction (Exam 1) > Flashcards

3 - Visual Direction (Exam 1) Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What 3 sources of information are required to determine the location of target?

A
  1. Relative position
  2. Absolute distance
  3. Egocentric point of reference
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is relative position of a target determined?

A

Retinocentric/oculocentric direction
Monocular distance cues
Stereopsis

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

How is absolute distance of a target determined?

A

Vergence eye movements
Monocular distance cues
Vertical disparity

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

What is the egocentric point of reference?

A

Position of the eye with respect to head and body

Cyclopean eye

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

What is retinocentric (oculocentric) direction?

A

Location expressed relative to the fovea of the viewing eye - specific to each eye

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

What is the Cartesian coordinate system?

A

Numeric values assigned to oculocentric direction

Fovea has oculocentric direction of ZERO

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

What was shown by Hering’s window experiment?

A

The perceived location of targets can differ significantly from their physical locations depending on the viewing situation.

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

What is the relationship between inputs and outputs of the visual system?

A

Physical inputs of oculocentric directions are processed to produce perceived output of directions relative to a virtual reference point.

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

How many fundamental laws of visual direction are there?

A

Four

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

What is the first law of visual direction?

A

The perceived direction of all targets are judged from the cyclopean eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many parts of Law II of visual direction are there

A

two parts

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

What is part a of the second law of visual direction?

A

All targets perceived on the primary visual line will be perceived as on a primary visual direction

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

What is part b of the second law of visual direction?

A

If two target lie on the same visual line they will be perceived as in the same visual direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How many parts of Law III of visual direction are there?

A

two parts

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

What is part a of the third law of visual direction?

A

All targets on secondary visual lines will be perceived as on secondary visual directions which connect to the cyclopean eye

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

What is part b of the third law of visual direction?

A

The angle between the primary and secondary visual line in a given eye is equal to the perceived angle between the primary and secondary visual direction.

17
Q

How many parts of Law IV of visual direction are there?

A

one part

18
Q

What is the fourth law of visual direction?

A

Under binocular conditions, every visual line in one eye has a corresponding visual line in the other eye that shares the same visual direction.

19
Q

Will two separate targets that resolve at the fovea be resolved in the retinal periphery?

A

Sometimes

If the separation between two targets is large enough, it will be resolved at the fovea and in the periphery

20
Q

What is 1 example of corresponding points?

A

The foveas of each eye.

21
Q

What is the horopter?

A

The locus of all targets in space that stimulate corresponding points

22
Q

What is the difference between the theoretical horopter (Veith-Muller Circle) and the empirical horopter?

A

The Veith-Muller Circle is circular

The empirical horopter is elliptical

23
Q

What does the horopter pass through in each eye?

A

The fixation point and nodal point of each eye

24
Q

If targets are located off the horopter, what types of points will be stimulated?

A

Non-corresponding points

25
Q

What is Panum’s Fusional Space?

A

A 3D volume of space around the empirical horopter in which targets that stimulate non-corresponding retinal points appear single

26
Q

How is version angle calculated?

A

Average of left and right eye positions in orbit relative to axis parallel to the median plane (straight ahead)

27
Q

How is headcentric direction computed for targets on the Horopter?

A

Average of oculocentric directions plus the version angle

28
Q

How is headcentric direction computed for targets off the Horopter but within Panum’s Fusional Space?

A

The same as headcentric direction for targets on the horopter (average of oculocentric directions plus the version angle)

29
Q

How is headcentric direction computed for targets off the Horopter and outside Panum’s Fusional Space?

A

Headcentric direction is separate for OD and OS

Each eye individually is the oculocentric direction plus the version angle

30
Q

In what way does the image move compared to the occluder with an esophoria?

A

Moves against occluder motion

31
Q

In what way does the image move compared to the occluder with an exophoria?

A

Moves with occluder motion

32
Q

How is diplopia different from confusion?

A

Diplopia is when a target is perceived in two different headcentric visual directions
Confusion is when two dissimilar targets are perceived in a one single headcentric visual direction

33
Q

What is a sensory mechanism that avoids diplopia and confusion?

A

Suppression

Only the image from one eye is seen so two images are not possible

Vision Science 2 (6 decks)

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