PSYCH 3220 Exam 3 unit 3

what are two functions of color perception

it helps us identify and classify objects and organize or understand scenes

what is color constancy

the tendency to perceives an object’s hue as relatively stable despite changes in illumination

what is one possible explanation for people seeing “the dress” as different colors

they may make different assumptions about the color of the illumination and compensate for it differently

what is lightness constancy

the tendency to perceive an object’s lightness as relatively stable under different intensities of illumination

what is memory color

the influence of an object’s familiar or characteristic color on how we perceive its color

what are the three perceptual dimensions of color

hue, saturation, and lightness or value

what is hue

the dimension describing chromatic color, such as red, green, yellow, or blue

what is saturation

the intensity or purity of a color; adding white makes a color less saturated

what does the trichromatic theory propose

color vision begins with three receptor mechanisms: the three types of cones, whose sensitivity ranges overlap

what behavioral evidence supports trichromatic theory

color-matching experiments showed that combinations of three appropriately chose lights can match a wide range of perceived colors

what are protanopia, deuteranopia, and tritanopia

color-vision deficiencies associated respectively with absent long-wavelength. medium-wavelength, and short-wavelength cone pigments

what are Ishihara plates used for

screening for color-vision deficiencies using patterns made of colored dots

what does opponent-process theory propose

later visual processing uses opposing responses in color mechanisms, including red-green and blue-yellow, as well as a black-white lightness mechanism

how do trichromatic and opponent-process theories fit together

Trichromatic theory describes processing at the cones; opponent processes describe subsequent stages of the visual pathway

where have opponent neurons been found

in the retina and lateral geniculate nucleus (LGN)

what is achromatopsia, and what area is associated with it in your notes

an impairment in color perception associated with damage to V4

how does a novelty-preference procedure test infant color perception

researchers compare how long an infant looks at different-colored stimuli, using the tendency to look longer at something novel as evidence of discrimination