Chapter 5

Front 1

Color

Back 1

Not a physical property but rather a psychophysical property

Front 2

Detection

Back 2

Wavelengths of light must be detected in the first place

Front 3

Discrimination

Back 3

We must be able to tell the difference between one wavelength (or mixture of wavelengths) and another

Front 4

Appearance

Back 4

We want to assign perceived
colors to lights and surfaces in the world and have
those perceived colors be stable over time,
regardless of different lighting conditions

Front 5

S-cones

Back 5

detect short wavelengths

Front 6

M-cones

Back 6

detect medium wavelengths

Front 7

L-cones

Back 7

detect long wavelengths

Front 8

Photopic

Back 8

Light intensities that are bright enough to
stimulate the cone receptors and bright enough to
“saturate” the rod receptors

Front 9

Scotopic

Back 9

Light intensities that are bright enough to
stimulate the rod receptors but too dim to stimulate
the cone receptors

Front 10

The problem of univariance

Back 10

An infinite set of different wavelength–intensity combinations can elicit exactly the same response from a single type of photoreceptor

Front 11

Rhodopsin

Back 11

All rods contain the same photopigment
molecule

Front 12

Trichromatic theory of color vision (trichromacy)

Back 12

The theory that the color of any light
is defined in our visual system by the relationships
of three numbers, the outputs of three receptor
types now known to be the three cones. Also known as the Young–Helmholtz theory

Front 13

Isaac Newton

Back 13

discovered that white light is composed of a spectrum of hues by using a prism And that adding a second prism, recombined the hues into a white light!!

Front 14

Metamers

Back 14

Mixtures of different wavelength that
look identical.any pair of stimuli that are perceived as identical in spite of physical differences

Front 15

Additive color mixture

Back 15

A mixture of lights.

Front 16

Subtractive color mixing

Back 16

A mixture of pigments! If pigment A and B mix, some of the light shining on the surface will be subtracted by A and some by B. Only the remainder contributes to the
perception of color

Front 17

Cone-opponent cell

Back 17

A neuron whose output is
based on a difference between sets of cones.

Front 18

Color space

Back 18

A three-dimensional space that describes all colors. There are several possible color spaces

Front 19

RGB color space

Back 19

Defined by the outputs of short, medium, and long wavelength lights

Front 20

HSB color space

Back 20

Defined by hue, saturation, and brightness

Front 21

Hue

Back 21

The chromatic (color) aspect of light

Front 22

Saturation

Back 22

The chromatic strength of a hue G

Front 23

Brightness

Back 23

The distance from black in color space

Front 24

Opponent color theory

Back 24

The theory that perception
of color is based on the output of three
mechanisms, each of them based on an opponency
between two colors:
Red–green
blue–yellow
black–white

Front 25

Ewald Hering (1834–1918)

Back 25

noticed that some color combinations are legal while others are illegal

Front 26

hue cancellation

Back 26

paradigm (typical example) to
determine the wavelengths of unique hues

Front 27

Unique hue

Back 27

Any of four colors that can be
described with only a single color term: Red,
yellow, green, blue

Front 28

Cerebral achromatopsia

Back 28

An inability to perceive colors; caused by damage to the central nervous system

Front 29

Afterimages

Back 29

A visual image seen after a stimulus has been removed

Front 30

Negative afterimage

Back 30

An afterimage whose polarity is the opposite of the original stimulus.

Front 31

Colors are complementary

Back 31

Red produces green (and vice-versa)
 
Yellow produces blue (and vice-versa)

Front 32

Deuteranope

Back 32

Due to absence of M-cones

Front 33

Protanope

Back 33

Due to absence of L-cones

Front 34

Tritanope

Back 34

Due to absence of S-cones

Front 35

Color-anomalous

Back 35

Two of cones are so similar that they can’t make discriminations based on them

Front 36

Cone monochromat

Back 36

Only one cone type; truly color-blind

Front 37

Rod monochromat

Back 37

No cones of any type; truly color-blind, badly visually impaired in bright light

Front 38

Cultural relativism

Back 38

In sensation and perception, the idea that basic perceptual experiences (e.g., color perception) may be determined in part by the cultural environment

Front 39

Roberson et al. (1999)

Back 39

work with the Berinmo (a few color words), plus a new color distinction in the GREEN space.

Front 40

Color contrast

Back 40

A color perception effect in which the color of one region induces the opponent color in a neighboring region

Front 41

Color assimilation

Back 41

A color perception effect in which two colors bleed into each other, each taking on some of the chromatic quality of the other

Front 42

Related color

Back 42

A color, such as brown or gray, that is seen only in relation to other colors 
A “gray” patch in complete darkness appears white
A “brown” patch will look yellow or orange.

Front 43

Color constancy

Back 43

The tendency of a surface to appear the same color under a fairly wide range of illuminants

Front 44

Illuminant

Back 44

The light that illuminates a surface (source of light)

Front 45

Assumptions about surfaces

Back 45

real surfaces reflect a wide range of wavelengths

Front 46

Synesthesia

Back 46

Most common: grapheme --> color synthesia