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PSYC 304: Sensation & Perception > Ch. 1-4 > Flashcards

Ch. 1-4 Flashcards

1
Q

Nativism

A

our abilities are innate; knowledge comes from the mind

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2
Q

Empiricism

A

objectivity; we can make observations; knowledge comes from the outside world and our experiences

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3
Q

Plato

A

Nativist; ideas are superior over materials; sensory organs that detect, but we are the ones who make judgments; cannot trust our senses

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4
Q

Aristotle

A

Empiricist; senses provide raw material for knowledge; can trust our senses; tabula rasa

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5
Q

tabula rasa

A

we are born blank slates and our experiences write on that blank space to form our knowledge

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6
Q

Rene Descartes

A

dualist; believed that mind and body are separate entities

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7
Q

George Berkeley

A

there are limitations to our perceptions; not that we cannot trust our senses, but that there are limitations; have to trust ideas more

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8
Q

Berkeley’s logical deducation

A

we perceive ordinary objects; we perceive only ideas; therefore, ordinary objects are ideas

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9
Q

followers of Plato

A

Rene Descartes and George Berkeley

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10
Q

followers of Aristotle

A

Thomas Hobbs and John Locke

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11
Q

Thomas Hobbs

A

empiricist; without input, there is nothing to generate thought; mental activity is a consequence of sensation and perception

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12
Q

John Locke

A

empiricist; there are first sensory impressions; parts = whole

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13
Q

method of constant stimuli

A

when an experimenter presents something, a stimulus, and the participant says “Yes, I perceive it” or “No, I don’t perceive it”; many stimuli with different intensities; repeat measures multiple times then average the responses or otherwise describe the pattern of results

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14
Q

example of method of constant stimuli

A

hearing test with presenting tones

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15
Q

absolute threshold

A

50% chance of perceiving a stimuli

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16
Q

method of limits

A

same as method of constant stimuli but done in sequence rather than at random; in increasing or decreasing order

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17
Q

method of adjustment

A

same as method of limits except the participant is in control of adjusting the stimulus

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18
Q

signal detection theory

A

two distributions overlapping, can be more separated or can be more layered; criterion; quanities the response of an observer to the presentation of a signal in the presence of “noise”

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19
Q

hit [p(Y/Y)] in signal detection theory

A

detect a stimulus that is actually there

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20
Q

false alarm [p(N/Y)] in signal detection theory

A

detect a stimulus that is not there

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21
Q

miss [p(Y/N)] in signal detection theory

A

stimulus is present, but not detected

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22
Q

correct rejection [p(N/N)] in signal detection theory

A

stimulus is not present, and is not detected

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23
Q

d’ (d-prime)

A

distance between the peaks (means) of the distributions; describes how easy the stimulus is detected when “noise” is present

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24
Q

the larger the d’…

A

the more likely a hit

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25
Q

receiver operating characteristic (ROC)

A

graphs the hits, misses, false alarms, and correct rejections

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26
Q

cross-modeling matching

A

comparing sensations; compare a sensation to another experience to get a better understanding of what someone is perceiving; measure someone’s experience

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27
Q

neuron

A

dendrites, cell body, nucleus, myelin sheath, axon, axon terminals; impulses go from dendrites to the axon terminals

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28
Q

types of neurons

A

multipolar interneurons, motor neurons, sensory neurons

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29
Q

myelin sheath

A

protects the axon and increases the speed of impulse transmission; a series of Schwann cells; action potential must “jump” from node to node

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30
Q

action potential unmyelinated neuron

A

slower conduction of action potential along an unmyelinated axon (10 m/s)

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31
Q

action potential myelinated neuron

A

rapid, saltatory action potential along myelinated axon (150 m/s)

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32
Q

synapse

A

gap between neurons; transfer neurotransmitters

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33
Q

brain lobes

A

frontal lobe, parietal lobe, occipital lobe, temporal lobe

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34
Q

frontal lobe

A

higher executive functioning, speech, motor cortex, frontal association area

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35
Q

parietal lobe

A

spatial processing, somatosensory cortex, speech, taste, reading, somatosensory association area

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36
Q

occipital lobe

A

vision

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37
Q

temporal lobe

A

memory, smell, hearing, auditory association area

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38
Q

corpus callosum

A

allows communication between the two hemispheres

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39
Q

cerebellum

A

fine motor movements, memory

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40
Q

properties of light

A

light can be absorbed, scattered, reflected, transmitted, or refracted

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41
Q

transmitted

A

passes through

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42
Q

refracted

A

breaks the light apart into different wavelengths; like light hitting a prism

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43
Q

primary layers (outer) of the eye

A

sclera, cornea

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44
Q

sclera

A

provides support and keeps pressure; basically keeps the whole eye together

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45
Q

cornea

A

thin layer of clear fibers with unmyelinated nerve endings; refracts light

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46
Q

primary layers (middle) of the eye

A

choroid, ciliary body, iris, pupil, lens, vitreous chamber

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47
Q

choroid

A

network blood vessels; heavy pigmentation; prevents scattering of light

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48
Q

ciliary body

A

produces aqueous humor, provides nourishment for the cornea, helps maintain the shape of the overall eye

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49
Q

iris

A

pigment that gives people the color of their eyes, contains blood vessels, essentially a muscle

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50
Q

pupil

A

allows light to enter the eye, controlled by the iris, autonomic nervous system process

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51
Q

lens

A

three parts: capsule, epithelial layer, lens; zonules of zinn

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52
Q

zonules of zinn

A

accomodation; ciliary muscle; focuses refracted light

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53
Q

vitreous chamber

A

clear liquid; nonrenewable; helps maintain the shape of the eye

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54
Q

primary layers (inner) of the eye

A

retina, visual optics

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55
Q

retina

A

a light-sensitive membrane in the back of the eye that contains photoreceptors and other cell types that transduce light; sensory transduction –> when a physical stimulus (light) is changed into neuronal energy

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56
Q

visual optics

A

emmetropia, myopia, hyperopia, astigmatism

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57
Q

emmetropia

A

normal vision

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58
Q

myopia

A

nearsightedness

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59
Q

hyperopia

A

farsightedness

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60
Q

astigmatism

A

lens not accommodating correctly

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61
Q

duplex retina theory

A

rods and cones in the retina

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62
Q

photoreceptors

A

rods and cones; the cells that capture light and initiate the act of seeing

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63
Q

3 segments of photoreceptors

A

outer, inner, and synaptic terminal

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64
Q

outer segment of photoreceptors

A

stores pigment, chromophore captures light, rhodopsin

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65
Q

rhodopsin

A

pigment in rods

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66
Q

inner segment of photoreceptors

A

produces pigment

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67
Q

retinal eccentricity

A

the distance between the retinal image and the fovea

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68
Q

foveal center

A

indent in the back of the eye with highest visual acuity

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69
Q

layers of the retina

A

rods and cones, horizontal cells, amacrine cells, bipolar cells, ganglion cells

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70
Q

bipolar cells

A

messenger of information; connected to rods and cones

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71
Q

diffuse bipolar cells

A

hook up to multiple photoreceptors; project to M ganglion cells

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72
Q

midget bipolar cells

A

connect to single cones; send signals to P ganglion cells

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73
Q

luminance levels

A

scotopic, mesopic, photopic

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74
Q

scotopic

A

starlight, cannot see color, only rods activated; nighttime vision

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75
Q

mesopic

A

can see some color; bright full moon at night; cones and rods activated; Purkinje shift –> shifting cones to rods; dusk; long wavelength to short wavelength

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76
Q

photopic

A

rod saturation begins; only cones activated; good color vision; daytime vision

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77
Q

ON-center ganglion cell

A

spot in center activates the cell; spot in surround turns off the cell of receptive field

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78
Q

OFF-center ganglion cell

A

spot in center turns off the cell; spot in surround activates the cell of receptive field

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79
Q

types of ganglion cells

A

parvo cells, magno cells, konio cells

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80
Q

visual pathway

A

optic tract, optic chiasm, lateral geniculate nucleus (LGN), visual cortex

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81
Q

properties of LGN

A

thalamus, receives fibers, output fibers; made up of ganglion cell pathways

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82
Q

functions of LGN

A

relay station; feedback loop –> light intensity, control over retinal outputs

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83
Q

primary visual cortex (striate cortex)

A

V1; simple and complex cells; sends information to V2

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84
Q

secondary visual cortex (extrastriate cortex)

A

V2

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85
Q

objective properties of light

A

radiance, lumen, illuminance, luminance, reflectance, retinal illuminance

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86
Q

subjective properties of light –> what is perceived by someone

A

brightness and lightness

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87
Q

lumen

A

one lumen is one candlelight

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88
Q

illuminance

A

the amount of light falling on a surface

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89
Q

luminance

A

amount of light reflected off of a surface

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90
Q

reflectance

A

percent of light falling on the surface that is reflected

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91
Q

retinal illuminance

A

the amount of light falling on the retina

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92
Q

brightness

A

amount of light from the source or being reflected

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93
Q

lightness

A

percentage of reflected light relative to the total light on the surface

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94
Q

visual angle

A

determined by size –> actual size of stimulus and size on the retina; proportion: object size/distance

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95
Q

Fourier analysis

A

take the whole, visual scene, and break it down into its component parts, sine waves

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96
Q

forms of spatial grating

A
  • square-wave grating: hard lines between light and dark; sawtooth waves
  • sine wave grating –> not a simple transition between light and dark; sine waves
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97
Q

low spatial frequency filters

A

encode coarse luminance variations in the world (e.g., large objects, overall shape)

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98
Q

high spatial frequency filters

A

respond to the fine spatial structure of the world (e.g., small objects, detail)

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99
Q

cycle

A

one repetition; from dark bar to light bar

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100
Q

four different component that can be manipulated in the Gabor Patches to observe neural responses

A

contrast, spatial frequency, spatial phase, orientation

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101
Q

contrast

A

difference in illumination; object vs. background, dim area vs. light area on object

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102
Q

contrast sensitivity function (CSF)

A

a function describing how the sensitivity to contrast depends on the spatial frequency of the stimulus

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103
Q

simple cell

A

a cortical neuron whose receptive field has clearly defined excitatory and inhibitory regions; edge detector; stripe detector

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104
Q

complex cell

A

a cortical neuron whose receptive field does not have clearly defined excitatory and inhibitory regions; tuned to a particular orientation and spatial frequency and shows an ocular preference

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105
Q

hypercolumn

A

a 1-millimeter block of striate cortex containing two sets of columns, each covering every possible orientation (0-180 degrees), with one set preferring input from the left eye and one set preferring input from the right eye

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106
Q

4 factors that hypercolumns are sensitive to

A

left or right eye, line orientation, line width, color

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107
Q

what pathway

A

ventral pathway that goes to temporal lobe; visual semantics

108
Q

visual semantics

A

when you look at a desk, you recognize it as a desk

109
Q

where pathway

A

dorsal pathway; where is it in the environment

110
Q

contours

A

object edges; quick, sudden changes in light intensity; first order: quick changes, exist in reality, luminance contour

111
Q

illusory contours

A

color based; created by the brain; does not exist in reality

112
Q

context

A

refers to the environment the stimuli is in

113
Q

subjective contours

A

second order or emergent contours: line orientation, texture; perceived edges of surfaces in locations where there is no physical contour in the image

114
Q

structuralism

A

theory about how the visual system puts together information; Wilhelm Wundt, E. B. Titchener; reduce brain to structures, experiences to basic components

115
Q

Gestalt principles

A

law of Prägnanz (good figure), law of proximity, law of similarity, law of good continuation, law of symmetry, law of closure, law of common fate

116
Q

law of Prägnanz (good figure)

A

ordering of information, regular, orderly, symmetric, simplest

117
Q

law of proximity

A

based on grouping; objects close together = grouped as a set

118
Q

law of similarity

A

based on comparing objects, then grouping them together; similar objects are grouped together

119
Q

law of good continuation

A

based on an object’s continuum, direction, likelihood of relatability

120
Q

law of closure

A

based on experience with the world; fill in missing parts

121
Q

law of common fate

A

based on motion; similar motion = grouping

122
Q

sensation

A

the ability to detect a stimulus and, perhaps, to turn that detection into a private experience

123
Q

perception

A

the act of giving meaning to a detected sensation

124
Q

qualia

A

private conscious experiences of sensation or perception

125
Q

methods for testing sensation and perception

A

thresholds, scaling (measuring private experience), signal detection theory, sensory neuroscience, neuroimaging, computational methods

126
Q

Gustav Fechner

A

founder of psychophysics; thought it would be possible to describe the relation between mind and body using mathematics

127
Q

dualism

A

the idea that the mind has an existence separate from the material world of the body

128
Q

materialism

A

the idea that the only thing that exists is matter, and that all things, including the mind and consciousness, are the results of interaction between bits of matter

129
Q

panpsychism

A

the idea that the mind exists as a property of all matter— that is, all matter has consciousness

130
Q

psychophysics

A

the science of defining quantitative relationships between physical and psychological (subjective) events

131
Q

two-point touch threshold

A

the minimum distance at which two stimuli are just perceptible as separate

132
Q

just noticeable difference (JND)

A

the smallest detectable difference between two stimuli, or the minimum change in a stimulus that enables it to be correctly judged as different from a reference stimulus

133
Q

Weber’s law

A

the principle describing the relationship between stimulus and resulting sensation that says the just noticeable difference is a constant fraction of the comparison stimulus

134
Q

Fechner’s law

A

a principle describing the relationship between stimulus and resulting sensation that says the magnitude of subjective sensation increases proportionally to the logarithm of the stimulus intensity

135
Q

absolute threshold

A

the minimum amount of stimulation necessary for a person to detect a stimulus 50% of the time

136
Q

scaling methods

A

used to figure out how strong one’s experiences are

137
Q

magnitude estimation

A

a psychophysical method in which the participant assigns values according to perceived magnitudes of the stimuli

138
Q

cross-modality matching

A

the ability to match the intensities of sensations that come from different sensory modalities; allows insight into sensory differences

139
Q

criterion (signal detection theory)

A

an internal threshold that is set by the observer; if the internal response is above criterion, the observer detects the stimulus; if the internal response is below criterion, the observer does not detect the stimulus

140
Q

sensitivity (signal detection theory)

A

a measure that defines the ease with which an observer can tell the difference between the presence and absence of a stimulus or the difference between Stimulus 1 and Stimulus 2; d’ (d-prime)

141
Q

receiver operating characteristic (ROC) curve

A

graphical plot of signal detection theory of the hit rate as a function of the false-alarm rate; if these are the same, points fall on the diagonal, indicating that the observer cannot tell the difference between the presence and absence of the signal; as the observer’s sensitivity increases, the curve bows upward toward the upper left corner; that point represents a perfect ability to distinguish signal from noise

142
Q

excitatory

A

some neurons increase the response of the next neuron

143
Q

inhibitory

A

some neurons decrease the response of the next neuron

144
Q

two ways to conceptualize light

A

as a wave or as a stream of photons

145
Q

wave

A

an oscillation that travels through a medium by transferring energy from one particle or point to another without causing any permanent displacement of the medium

146
Q

photon

A

a quantum of visible light or other form of electromagnetic radiation demonstrating both particle and wave properties

147
Q

hue

A

the perceptual attribute of colors that enables us to classify visible light wavelengths

148
Q

what happens to light on its way from a star to an eye

A
  • some photons are absorbed when they reach the atmosphere
  • some of the light is scattered by particles in the atmosphere
  • most of the photons make it through the atmosphere and eventually hit the surface of an object
  • if it strikes a light-colored surface, most of the light would be reflected
  • if it strikes a dark-colored surface, most of the light would be absorbed
  • light that is neither absorbed nor reflected is transmitted
  • if the light travels through glass, it is refracted
149
Q

scatter

A

to disperse in an irregular fashion

150
Q

reflect

A

to redirect something that strikes a surface

151
Q

cornea

A

transparent outermost layer of the eye

152
Q

aqueous humor

A

watery fluid in the anterior chamber (space between the cornea and the iris) of the eye

153
Q

vitreous humor

A

the transparent fluid that fills the vitreous chamber in the posterior part of the eye

154
Q

four optical components of the eye that must be perfectly matched to the length of the eyeball to focus on distant light

A

cornea, aqueous humor, lens, and vitreous humor

155
Q

accommodation

A

the process by which the eye changes its focus; lens brings close things into focus with ciliary muscle (iris)

156
Q

presbyopia

A

the age-related loss of accommodation, which makes it difficult to focus on near objects

157
Q

cataract

A

an opacity of the crystalline lens

158
Q

emmetropia

A

the condition in which there is no refractive error because the refractive power of the eye is perfectly matched to the length of the eyeball

159
Q

refractive error

A

a very common disorder in which the image of the world is not clearly focused on the retina

160
Q

myopia

A

nearsightedness; a common condition in which light entering the eye is focused in front of the retina, and distant objects cannot be seen sharply; eyeball is too long for the optics

161
Q

hyperopia

A

farsightedness; a common condition in which light entering the eye is focused behind the retina and accommodation is required in order to see near objects clearly; eyeball is too short for the optics

162
Q

astigmatism

A

a visual defect caused by the unequal curving of one or more of the refractive surfaces of the eye, usually the cornea

163
Q

fundus

A

the back layer of the retina

164
Q

optic disc

A

point where the arteries and veins that feed the retina enter the eye and where axons of ganglion cells leave the eye via the optic nerve; blind spot

165
Q

fovea

A

a small pit containing the highest concentration of cones and no rods; produces the highest visual acuity

166
Q

optical coherence tomography (OCT)

A

method to see each layer of the retina in cross section

167
Q

transduction in the retina

A

rods and cones transduce light into neuronal energy

168
Q

when photoreceptors sense light…

A

they can stimulate neurons in the intermediate layers, including bipolar cells, horizontal cells, and amacrine cells; these neurons then connect with the frontmost layer of the retina, which is made up of ganglion cells, whose axons pass through the optic nerve to the brain

169
Q

each cone has…

A

one of three different photopigment that differ in the wavelength at which they absorb light most efficiently

170
Q

four primary ways in which the visual system adjusts to changes in illumination

A
  • pupil size
  • photopigment regeneration
  • duplex retina
  • neural circuitry
171
Q

pupil size

A

can adjust diameter of pupil to account for different lighting conditions

172
Q

photopigment regeneration

A

after a photopigment molecule is bleached (used to detect a photon), the molecule must be regenerated before it can be used again to absorb another photon; slow regeneration; helps increase sensitivity range

173
Q

duplex retina for adjustment to changes in illumination

A

use rods to see when the light is low and cones take over when there is too much light for the rods to function well; light compensation mechanism

174
Q

neural circuity for adjustment to changes in illumination

A

ganglion cells will encode the pattern of relatively dark areas in the retinal image

175
Q

receptive field

A

the region on the retina in which visual stimuli influence a neuron’s firing rate

176
Q

five major classes of neurons in the retina

A

photoreceptors, horizontal cells, bipolar cells, amacrine cells, and ganglion cells

177
Q

parts of a photoreceptor

A

outer segment, inner segment, and synaptic terminal

178
Q

rhodopsin

A

the visual pigment found in rods

179
Q

visual pigment consists of…

A

a protein (opsin) and a chromophore

180
Q

chromophore

A

the light-catching part of the visual pigments of the retina

181
Q

horizontal cell

A

a specialized retinal cell that contacts both photoreceptor and bipolar cells; run perpendicular to the photoreceptors

182
Q

lateral inhibition

A

antagonistic neural interaction between adjacent regions of the retina

183
Q

amacrine cells

A

a retinal cell found in the inner nuclear layer that makes synaptic contacts with bipolar cells, ganglion cells, and other amacrine cells

184
Q

form a vertical pathway in the retina

A

photoreceptors, bipolar cells, and ganglion cells

185
Q

bipolar cell

A

a retinal cell that synapses with either rods or cones (not both) and with horizontal cells then passes the signals on to ganglion cells

186
Q

diffuse bipolar cell

A

a bipolar retinal cell whose processes are spread out to receive input from multiple cones

187
Q

midget bipolar cells

A

a small bipolar cell in the central retina that receives input from a single cone and pass information on to single ganglion cells

188
Q

ON bipolar cell

A

a bipolar cell that depolarizes in response to an increase in light captured by the cones

189
Q

OFF bipolar cell

A

a bipolar cell that hyperpolarizes in response to an increase in light captured by the cones

190
Q

ganglion cell

A

a retinal cell that receives visual information from photoreceptors via two intermediate neuron types (bipolar and amacrine cells) and transmits information to the brain and midbrain

191
Q

P ganglion cell

A

a small ganglion cell that receives excitatory input from single midget bipolar cells and feeds the parvocellular layer of the LGN

192
Q

M ganglion cell

A

a ganglion cell resembling a little umbrella that receives excitatory input from diffuse bipolar cells and feeds the magnocellular layer of the LGN

193
Q

koniocellular cell

A

a neuron located between the magnocellular and parvocellular layers of the LGN; bistratified ganglion cells

194
Q

amblyopia

A

a developmental disorder characterized by reduced spatial vision in an otherwise healthy eye, even with proper correction for refractive error

195
Q

minimum visible acuity

A

refers to the smallest object that one can detect

196
Q

minimum resolvable acuity

A

refers to the smallest angular separation between neighboring objects that one can resolve

197
Q

minimum recognizable acuity

A

refers to the angular size of the smallest feature that one can recognize or identify

198
Q

minimum discriminable acuity

A

refers to the angular size of the smallest change in a feature that one can discriminate

199
Q

contrast sensitivity function (CSF)

A

a function describing how the sensitivity to contrast depends on the spatial frequency (size) of the stimulus

200
Q

contrast threshold

A

the smallest amount of contrast required to detect a pattern

201
Q

fourier analysis

A

a mathematical procedure by which any signal can be separated into component sine waves at different frequencies

202
Q

phase

A

the position of a grating relative to a fixed position measured in degrees, where one complete cycle is 360 degrees

203
Q

when spatial frequency of the grating is too low…

A

the ganglion cell responds weakly because part of the fat, bright bar of the grating lands in the inhibitory surround, damping the cell’s response

204
Q

when spatial frequency of the grating is too high…

A

the ganglion cell responds weakly because both dark and bright stripes fall within the receptive-field center, washing out the response

205
Q

lateral geniculate nucleus (LGN)

A

a structure in the thalamus, part of the midbrain, that receives input from the retinal ganglion cells and has input and output connections to the visual cortex

206
Q

6 layers of the LGN split into 2 types

A

magnocellular layers and parvocellular layers

207
Q

magnocellular layers

A

either of the bottom two neuron-containing layers of the LGN, the cells of which are physically larger than those in the top four layers

208
Q

parvocellular layers

A

any of the top four neuron-containing layers of the LGN, the cells of which are physically smaller than those in the bottom two layers

209
Q

koniocellular cells

A

a neuron located between the magnocellular and parvocellular layers of the LGN

210
Q

left LGN

A

receives projections from the left side of the retina in both eyes

211
Q

right LGN

A

receives projections from the right side of both retinas

212
Q

striate cortex

A

the area of the cerebral cortex of the brain that receives direct inputs from the LGN as well as feedback from other brain areas; consists of six major layers

213
Q

cortical magnification

A

the amount of cortical area devoted to a specific region in the visual field

214
Q

consequence of cortical magnification

A

visual acuity declines in an orderly fashion with eccentricity

215
Q

visual crowding

A

the deleterious effect of clutter on peripheral object recognition; an essential bottleneck

216
Q

orientation tuning

A

the tendency of neurons in striate cortex to respond optimally to certain orientations and less to others

217
Q

ocular dominance

A

the property of the receptive fields of striate cortex neurons by which they demonstrate a preference, responding somewhat more rapidly when a stimulus is presented in one eye than when it is presented in the other

218
Q

each neuron in the striate cortex responds to a distinctive set of stimulus properties

A

stripes, edges, and/or gratings that are oriented at a particular angle, with a particular width or spatial frequency, possibly moving in a particular direction

219
Q

column

A

a vertical arrangement of neurons; neurons within a single column tend to have similar receptive fields and similar orientation preferences

220
Q

adaptation

A

a reduction in response caused by prior or continuing stimulation

221
Q

spatial-frequency channel

A

a pattern analyzer, implemented by an ensemble of cortical neurons, in which each set of neurons is tuned to a limited range of spatial frequencies

222
Q

extrastriate cortex

A

the region of cortex bordering the primary visual cortex and containing multiple areas involved in visual processing

223
Q

border ownership

A

when one object is in front of another there will be a visual border formed between the object and the background; that border is “owned” by the object; it is the edge of the object, not a property of the background

224
Q

what and where pathways

A

from the extrastriate regions of the occipital lobe, visual information moves out along two main pathways

225
Q

where pathway

A

heads up (dorsally) into the parietal lobe from the extrastriate regions; process information relating to teh location of objects in space and the actions required to interact with them; plays an important role in the deployment of attention

226
Q

what pathway

A

heads down (ventrally) into the temporal lobe from the extrastriate regions; appears to be the locus for the explicit acts of object recognition

227
Q

agnosia

A

a failure to recognize objects in spite of the ability to see them

228
Q

inferotemporal (IT) cortex

A

part of the cerebral cortex in the lower portion of the temporal lobe, important in object recognition; found to be connected to agnosia

229
Q

homologous regions

A

brain regions that appear to have the same function in different species

230
Q

fusiform face area (FFA)

A

a region of extrastriate visual cortex in humans that is specifically and reliably activated by human faces

231
Q

extrastriate body area (EBA)

A

a region of extrastriate visual cortex in humans that is specifically and reliably activated by images of the body other than the face

232
Q

parahippocampal place area (PPA)

A

a region of extrastriate visual cortex in humans that is specifically and reliably activated more by images of places than by other stimuli

232
Q

visual word form area (VWFA)

A

a region of extrastriate visual cortex in humans that is specifically and reliably activated more by images of written words than by other stimuli

233
Q

feedforward process

A

a process that carries out a computation one neural step after another, without need for feedback from a later stage to an earlier stage

234
Q

reverse-hierarchy theory

A

a theory that fast, feedforward processes can give you crude information about objects and scenes based on activity in high-level parts of the visual cortex

235
Q

mid-level (middle) vision

A

a loosely defined stage of visual processing that comes after basic features have been extracted from the image (low-level vision) and before object recognition and scene understanding (high-level vision)

236
Q

goal of mid-level vision

A

to organize the elements of a visual scene into groups that we can then recognize as objects

237
Q

illusory contour

A

a contour that is perceived even though nothing changes from one side of it to the other in an image

238
Q

occlusion

A

one guess the visual system may make that a line suddenly stops is becuase something else gets in the way, hiding it from view

239
Q

structuralism

A

in reference to perception, a school of thought that believed that complex objects or perception could be understood by analysis of the components

240
Q

Gestalt

A

in reference to perception, a school of thought stressing that the perceptual whole can be greater than the apparent sum of the parts; perceptual whole is more than the sum of its sensory parts

241
Q

Gestalt grouping rules

A

a set of rules describing which elements in an image will appear to group together

242
Q

texture segmentation

A

carving an image into regions of common texture properties

243
Q

parallelism

A

a rule for figure-ground assignment stating that parallel contours are likely to belong to the same figure

244
Q

symmetry

A

a rule for figure-ground assignment stating that symmetrical regions are more likely to be seen as figure

245
Q

camouflage

A

getting your features to group with the features of the environment so as to persuade an observer that your features do not form a perceptual group of their own

246
Q

ambiguity and perceptual “committees”

A

a host of rules, principles, and good guesses contribute to our organized perception of the world

247
Q

ambiguous figure

A

a visual stimulus that gives rise to two or more interpretations of its identity

248
Q

necker cube

A

an outline that is perceptually bi-stable; unlike the situation with most stimuli, two interpretations continually battle for perceptual dominance

249
Q

accidental viewpoint

A

a viewing position that produces some regularity in the visual image that is not present in the world

250
Q

figure-ground assignment

A

the process of determining that some regions of an image belong to a foreground object (figure) and other regions are part of the background (ground)

251
Q

principles at work in the assignment of regions to figure or ground

A
  • surroundedness
  • size –> the smaller region is likely to be the figure
  • symmetry –> a symmetrical region is more likely to be seen as a figure
  • parallelism –> regions with parallel contours are more likely to be seen as figures
  • relative motion –> how surface details move relative to an edge can also determine which portion of a display is the foreground figure and which is the background
252
Q

dealing with occlusion

A
  • relatability
  • heuristic
  • nonaccidental features
  • Gestalt principle of good continuation
253
Q

relatability

A

the degree to which two line segments appear to be part of the same contour

254
Q

heuristic

A

a mental shortcut

255
Q

nonaccidental features

A

a feature of an object that is not dependent on the exact (or accidental) viewing position of the observer

256
Q

global superiority effect

A

the finding in various experiments that the properties of the whole object take precedence over the properties of parts of the object

257
Q

summarizing mid-level vision

A
  • early-vision processes give us the local features in the visual world
  • mid-level vision processes begin the work of understanding what those local features might be telling us about the state of the world
  • bring together that which should be brought together (Gestalt grouping principles)
  • use what you know
  • avoid accidents
  • seek consensus and avoid ambiguity
258
Q

pandemonium model

A

an account of letter recognition, a relatively simple subset of the object recognition problem; used “demons” as metaphor for processes

259
Q

template

A

the internal representation of a stimulus that is used to recognize the stimulus in the world

260
Q

structural description

A

a description of an object in terms of the nature of its constituent parts and the relationships between those parts

261
Q

recognition-by-components model

A

model of object recognition, which holds that objects are recognized by the identities and relationships of their component parts

262
Q

geons

A

“geometric ions” out of which perceptual objects are built

263
Q

entry-level category

A

for an object, the label that comes to mind most quickly when we identify it; at the subordinate level, the object might be more specifically named; at the superordinate level, it might be more generally named

264
Q

holistic processing

A

processing based on analysis of the entire object or scene and not on adding together a set of smaller parts or features

265
Q

prosopagnosia

A

an inability to recognize faces; caused by damage to specific areas in the temporal lobe

266
Q

congenital prosopagnosia

A

a form of face blindness apparently present from birth

PSYC 304: Sensation & Perception (9 decks)

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