Sensation And Perception Exam 2

Front 1

Color

Front 2

Purpose of Color

Back 2

-eating (save yourself from two berries that look the same, but on color is poisonous)

-not being eaten (detect predators)

Front 3

Is Color Real?

Back 3

Color is not an objective truth, it's how we perceive wavelengths.

Front 4

Additive vs. Subtractive Color Mixing

Back 4

Additive: the creation of colors that occurs when lights of different colors are superimposed

Subtractive: the creation of colors that occurs when paints of different colors are mixed together

Front 5

Trichromatic Theory

Back 5

A theory proposing that our perception of color is determined by the ratio of activity in three receptor mechanisms with different spectral sensitivites

Front 6

Problem of Univariance

Back 6

any wavelength can produce any activation

Front 7

Metamers

Back 7

Two lights that have different wavelength distributions but are perceptually identical

Front 8

Ratio

Back 8

two areas that reflect the same amount of lights will have the same perceived lightness if the ratios of their intensities to the intensities of their surroundings are the same

Front 9

Opponent Process Theory

Back 9

claims that our perception of color is determined by the activity of two opponent mechanisms: a blue-yellow mechanism and a red-green mechanism (black-white for brightness)

in each mechanism, one color is excitatory and the other inhibatory

Front 10

Color Constancy

Back 10

the perception of an object's hue remains constant even when the wavelength distribution of the illumination is changed

Front 11

Lightness Constancy

Back 11

the constancy of our perception of an object's lightness under different intensities of illumination

Front 12

Chromatic Adaptation

Back 12

exposure to light in a specific part of the visual spectrum

this adaption can cause a decrease in sensitivity to light from the area of the spectrum that was presented during adaptation

Front 13

Reflectance Edge

Back 13

an edge between two areas where the reflectance of two surfaces changes

Front 14

Illumination Edge

Back 14

the border between two areas created by different light intensities in the two areas

Front 15

The Usefulness of Shadows

Back 15

known or irregular shapes help designate illumination

Front 16

Depth

Front 17

Oculomotor Cues

Back 17

Convergence: the inward movement of the eyes that occurs when we look at nearby objects

Accommodation: the change in the shape of the lens that occurs when we focus on objects at various distances

Front 18

Pictorial Cues (next 8 cards)

Back 18

sources of depth information that can be depicted in a picture

Front 19

Occlusion

Back 19

one object hides or partially hides another object from view, causing the hidden object to be perceived as being farther away

Front 20

Relative Height

Back 20

objects that have bases below the horizon appear to be farther away when they are higher in the field of view

Front 21

Relative Size

Back 21

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

Front 22

Perspective Convergence

Back 22

the perception that parallel lines in the distance converge as distance increases

Front 23

Familiar Size

Back 23

judgement of distance is based on knowledge of the sizes of objects

Front 24

Atmospheric Perspective

Back 24

objects that are farther away look more blurred and bluer than objects that are closer because we must look through more air and particles to see them

Front 25

Texture Gradient

Back 25

the visual pattern formed by a regularly textured surface that extends away from the observer

Front 26

Shadows

Back 26

can provide location (ex. ball floating above or resting on table) as well as enhance three-dimensionality

Front 27

Monocular Cues

Back 27

depth cue (such as overlap, relative size and height, familiar size, linear perspective, motion parallax, and accommodation) that can work when we use only one eye

Front 28

Binocular Cues

Back 28

depth cue that only works with both eyes

Front 29

Relative Disparity

Back 29

the difference between two objects' absolute disparity

Front 30

Absolute Disparity

Back 30

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

Front 31

Visual Angle

Back 31

the angle of an object relative to an observer's eye

because an object's visual angle is always determined relative to an observer, it's visual angle changes as the distance between the object and the observer changes

Front 32

Size Constancy

Back 32

occurs when the size of an object is perceived to remain the same even when it is viewed from different distances

Front 33

Illusions

Front 34

Muller-Lyer

Back 34

Front 35

Ponzo

Back 35

Front 36

Moon Illusion

Back 36