psych of perception chapter 10

Question 1

Müller-Lyer illusion

Answer 1

The Müller-Lyer illusion is an optical illusion consisting of three stylized arrows. When viewers are asked to place a mark on the figure at the midpoint, they tend to place it more towards the “tail” end.

Question 2

misapplied size constancy scaling

Answer 2

size constancy normally helps us maintain a stable perception of objects by taking distance into account

• misapplied size constancy scaling refers to a principle that is proposed by Richard Gregory, that when mechanisms that help maintain size constancy in the three-dimensional world are applied to two-dimensional pictures, an illusion of size sometimes results

Question 3

The Ponzo (or railroad track) Illusion

Answer 3

both animals are the same size, and so have the same visual angle, but the one on top appears longer. According to Gregory’s misapplied scaling explanation, the top animal appears larger because of depth information provided by the converging railroad tracks that make the top animal appear farther away

Question 4

The Ponzo (or railroad track) Illusion

Answer 4

both animals are the same size, and so have the same visual angle, but the one on top appears longer. According to Gregory’s misapplied scaling explanation, the top animal appears larger because of depth information provided by the converging railroad tracks that make the top animal appear farther away

Question 5

the Ames room

Answer 5

the Ames room causes two people of equal size to appear very different in size, this perception occurs even though both women are actually about the same height. The reason for this erroneous perception of size lies in the construction of the room. The construction of the room causes the woman on the left to have a much smaller visual angle than the one on the right.

Question 6

size-distance scaling

Answer 6

link between size constancy and depth perception has led to the proposal that size constancy is based on a mechanism called size–distance scaling that takes an object’s distance into account.

Question 7

size-distance equation

Answer 7

S = K ( R x D )
According to the size–distance equation, as a person walks away from you, the size of the person’s image on your retina (R) gets smaller, but your perception of the person’s distance (D) gets larger. These two changes balance each other, and the net result is that you perceive the person’s size (S) as remaining constant.
(S is perceived size, K is a constant, R is object’s retinal size, and D is the distance)

Question 8

the moon illusion

Answer 8

the moon appears larger on the horizon than when it is higher in the sky

Question 9

cue approach to depth perception

Answer 9

when the image is two-dimensional, we still need to explain how we get from flat image on the retina to a three-dimensional scene perception. One way researchers have approached this problem is to ask what information is contained in this two-dimensional image that enables us to perceive depth in the scene. this is called the cue approach to depth perception

Question 10

occlusion

Answer 10

the object that is partially covered must be at a greater distance than the object that is covering it
(near objects cover far objects)
pictorial cue

Question 11

oculomotor cues

Answer 11

cues based on our ability to sense the position of our eyes and the tension in our eye muscles: convergence and accommodation

Question 12

convergence

Answer 12

inward movement of the eyes when we focus on nearby objects

Question 13

accomodation

Answer 13

the shape of the lens changes when we focus on objects at different distances
to focus on the objects which is further, lens gets thinner, for objects near by - thicker

Question 14

monocular cues

Answer 14

cues that work with only one eye

Question 15

pictorial cues

Answer 15

pictorial cues are sources of depth information that can be depicted in a picture, such as the illustrations in book or the image on the retina

Question 16

relative height

Answer 16

objects that are below the horizon and have their bases higher in the field of view are usually seen as being more distant
* when objects are above the horizon, like the clouds, being lower in the field of view indicates more distance

Question 17

relative size

Answer 17

when two objects are of equal size, the one that is farther away will take up less of your field of view than the closer one

Question 18

perspective convergence

Answer 18

when parallel lines extend out from an observer, they are perceived as converging - becoming closer together - as distance increases
(parallel lines coming-together)

Question 19

familiar size

Answer 19

we use the cue of familiar size when we judge distance based on our prior knowledge of the sizes of objects

Question 20

atmospheric perspective

Answer 20

occurs when more distant objects appear less sharp and often have a slight blue tint, the farther away an object is, the more air and particles (dust, water droplets, airborne pollution) we have to look through, making objects that are farther away look less sharp and bluer than close objects

Question 21

texture gradient

Answer 21

elements that are equally spaced in a scene appear to be more closely packed as distance increases

Question 22

shadows

Answer 22

indicate where objects are located

Question 23

motion-produced cues

Answer 23

emerge when the observer is walking

Question 24

motion parallax

Answer 24

occurs when, as we move, nearby objects appear to glide rapidly past us, but more distant objects appear to move more slowly

Question 25

why motion parallax occurs?

Answer 25

image of near object and a far object move across the retina as the eye moves from position 1 to position 2, objects closer to perceiver moves further distance

Question 26

deletion and accretion

Answer 26

as an observer moves sideways, some things become covered (deletion), and others become uncovered (accretion)

Question 27

binocular depth information

Answer 27

the differences in the images received by our two eyes

Question 28

binocular disparity

Answer 28

depth perception created by input from both eyes
* difference in images from two eyes

Question 29

horopter

Answer 29

imaginary sphere that passes through the point of focus
*objects on the horopter fall on corresponding points on the two retinas

Question 30

corresponding retinal points

Answer 30

the places on each retina that would overlap if one retina could be slid on top of the other

Question 31

noncorresponding points

Answer 31

objects that do not fall on the horopter fall on noncorresponding points, these points make disparate image

Question 32

relaitive disparity

Answer 32

the difference between two objects’ absolute disparities

Question 33

angle of disparity

Answer 33

visual angle between the images of an object on the two (2) retinas

• when images of an object fall on corresponding points, the Angle of disparity is zero, when images fall on non-corresponding points, the Angle of disparity indicates the degree of non-correspondence

Question 34

absolute disparity

Answer 34

amount of absolute disparity indicates how far an object is from the horopter, greater disparity is associated with greater distance from the horopter

Question 35

stereopsis

Answer 35

the impression of depth that results from information provided by binocular disparity

Question 36

correspondance problem

Answer 36

How does the vi- sual system match the parts of the images in the left and right eyes that correspond to one another?

Question 37

visual angle

Answer 37

angle of an object relative to the observer’s eye, it depends on the size of the stimulus and on its distance from the observer

Question 38

size constancy

Answer 38

our perception of an object’s size remains relatively constant, even when we view an object from different distances, which changes the size of the object’s image on the retina

Question 39

Emmert’s law

Answer 39

the farther away an afterimage appears, the larger it will seem
this result follows from size–distance scaling equation, S = R x D

Question 40

angular size contrast theory

Answer 40

theory of the moon illusion is the angular size contrast theory, which states that the moon appears smaller when larger objects surround it
thus when the moon is elevated, the large expanse of sky surrounding it makes it appear smaller. However, when the moon is on the horizon, less sky surrounds it, so it appears larger

Question 41

apparent distance theory

Answer 41

according to apparent distance theory, the moon on the horizon appears more distant because it is viewed across the filled space of the terrain, which contains depth information; but when the moon is higher in the sky, it appears less distant because it is viewed through empty space, which contains little depth information