psych 367 mid 2 textbook ch 5-8

bottom-up processing

physical stimuli influence how we perceive them

top-down processing

our existing knowledge of objects influences how we perceive them

recognition

the ability to match a currently viewed item with an item from memory

representation

the process that translate stimulus information into a perceptual experience of that stimulus

perceptual organization

the process by which multiple objects in the environment are grouped, allowing us to identify those objects in complex scenes

grouping

elements in a figure are brought together into a common unit or object

segregation

process of distinguishing two objects as being distinct or discrete

figure-ground orgnaization

experience viewers have as to which part of an image is in the foreground and which part is in the background

images with __ borders are more likely to be seen as figure

convex

images with __ borders are more likely to be seen as ground

concave

law of good continuation

figures that have edges that are smooth are more likely to be seen as continuous than those with edges that have abrupt or sharp angles

law of proximity

elements that are close together tend to be perceived as a unified group

law of similarity

elements that are similar to one another tend ot be perceived as a unified gorup

law of symmetry

elements that are symmetrical ot one another tend to be perceived as a unified group

law of common fate

elements that are moving together tend to be perceived as a unified group

edge completion

perception of a physically absent, but inferred edge, allowing us to complete the perception of a partially hidden object

illusory contours

perceptual edges that exist because of edge completion but are not actually physically present

geons

basic units of objects and consist of simple shapes

recognition by components theory

object recognition occurs by representing each object as a combination of basic units that make up that object

viewpoint invariance

objects are seen as the same regardless of the vantage point relative to the viewer

dorsal pathway a.k.a

where pathway

ventral pathway a.k.a

what pathway

what area of the brain is involved in delineating shapes

V4 in the occupital lobe

information in the ventral pathway leaves the occipital lobe and heads into the __

inferotemporal area

neurons in the inferotemporal area are devoted to what

detecting particular kinds of objects in the visual field

fusiform face area

region in the brain designed for the recognition of familiar faces

where is the fusiform face area

ventral surface of the temporal lobe

occipital face area is responsible for what

making the initial identification of a face being a face

what cortex is the occipital face area located

extrastriate

prosopagnosia

damage to the fusiform face area

parahippocampal place area (PPA)

area in the inferotemporal cortex that has the specific function of scene recognition

topographic agnosia

deficit in recognizing spatial landscapes and is related to damage to the PPA

when is the extrastriate body area activated

when its cells view bodies/body parts but not faces

engram

specific location of a specific memory

visual spectrum

humans can see wavelengths of light that vary between 400-700 nm

wavelength

the distance between two peaks of light energy

what is sunlight

a mix of many different wavelengths that are blended together to be perceived as white light

heterochromatic light

white light consisting of many wavelengths

monochromatic lights

light of only one wavelength or a very narrow band of wavelengths

spectral reflectance

ratio of light reflected by an object at each wavelength

the colour of any object is determined by what

which wavelengths it reflects the most

achromatic

surfaces that reflect all light equally — judged to be white to grey to black

hue

the colour quality of the light and corresponds to the colour names

a quality

a value that changes, but it does not make the value larger or smaller

nonspectral colours

colours that are combinations of more than one monochromatic colour

saturation

the purity of light

brightness

the amount of light present and our experience of the intensity of this light

lightness

perceived intensity that relates to the amount of light that gets reflected by a surface

brightness applies to __

colours

lightness applies to __

white-grey-black continuum

additive colour mixing

creation of a new colour by a process that adds one set of wavelengths to another

subtractive colour mixing

the creation of a new colour by the removal of wavelengths from a light with a broad spectrum of wavelengths

additive colour mixing happens when __

we mix lights of different colours

subtractive colour mixing happens when __

we mix paints or other coloured materials

metamer

psychophysical colour match between two patches of light that have different sets of wavelengths

s-cone

maximum response to light at 420 nm (short-wavelength light)

m-cone

maximum response to light at 535 nm (medium)

L-cone

maximum response to light at 565 nm (long)

univariance

any single cone system is colour blind in the sense that different combinations of wavelength and intensity can result in the same response from the cone system

trichromatic theory of colour vision

to perceive any colour of light, we must have more than one receptor and that each type of receptor is sensitive to a different range of wavelengths

opponent-process theory of colour

colour perception arises from three opponent mechanisms, for red-green, blue-yellow, and black-white

colour afterimages

visual images that are seen after an actual visual stimulus has been removed

an afterimage is seen as the __ colour

complementary

simultaneous colour contrast

when our perception of one colour is affected by a colour that surrounds it

hue cancellation

an experiment in which observers cancel out the perception of a particular colour by adding light of the opponent colour

unique colours

colours that can be described only with a single colour term — red, green, blue, and yellow

cone-opponent cells

colour-sensitive cells in the LGN

colour-opponent cells

excited by one colour in the center and inhibited by its opponent colour in the surround

colour-opponent cells are __

red-green

blue-yellow

double-opponent cells

have a center that is excited by one colour and inhibited by the other

habituation

lack of responding to a repeated stimulus

dishabituation

the process of changing the stimulus after habituation occurs to cause the organism to respond again

colour variation

variations in the cone classes or cone photopigments that a person has in their eyes that may impact the way they perceive colours

genes that lead to colour deficiencies are on which chromosome

the X chromosome

anomalous trichromacy

a condition where all three cone systems are intact but one or more has an altered absorption pattern, leading to different metameric matches than most

prototanomalous

describes a trichromat with a different long (1) wavelength cone than is seen most commonly

deuternamalous

describes a trichromat with a different middle (2) wavelength cone than is seen most commonly

tritanamalous

describes a trichromat with a different short (3) wavelength cone than is seen most commonly

dichromat

only two working cone systems

protanopia

a lack of L-cones (1), leading to red-green deficiency; common + sex-linked

deuteranopia

a lack of M-cones (2), leading to red-green deficiency; common + sex-linked

tritanopia

a lack of S-cones (3), leading to blue-yellow colour deficiency; RARE and is not sex-linked

easiest way to identify colour deficiency?

Ishihara plates

the common name for protanopia is

red-green colour blind

unilateral dichromacy

dichromacy in one eye but trichromatic vision in the other

cortical achromatopsia

loss of colour vision due to damage in the occipital lobe + V4

what is the perceptual experience of cortical achromatopisa

seeing only in black and white, or the impression of washed out colours

constancy

our ability to perceive an object as the same object under different lighting and environmental conditions

lightness constancy

ability to perceive the relative reflectance of objects despite changes in illumination

colour constancy

ability to perceive colour of an object despite changes in the amount and nature of illumination

gelb effect

phenomenon whereby an intensely lit black object appears to be grey or white in a homogeneously dark space

the ratio principle

perceived lightness of an object is explained by the ratio of light it reflects rather than the absolute amount of light it reflects

cue approach to depth perception focuses on what

the observation that the image on the retina is 2D, we must infer the third dimension

what is a cue

factor that aids you in making a nonconscious and automatic deciison

monocular depth cues

information in the retinal image that gives information about depth and distance, but can be inferred from a single retina

pictoral cues

cues from which we can judge depth from static pictures

motion-based cues

moving objects / own motion allow us to make inferences about depth and distance

occlusion

occurs when one object partially hides or obstructs the view of a second object

relative height

objects closer to the horizon are seen as more distant

relative size

the more distant an object is, the smaller its image will be on the retina