The visual world Week 8 Flashcards
(87 cards)
1
Q
electromagnetic energy
A
Pulses of energy waves that can carry information from place to place
2
Q
wavelength
A
The distance between one wave peak and the next wave peak
3
Q
visible spectrum
A
The part of the electromagnetic spectrum that our eyes detect (only the range from about 400 to 700 billionths of a meter)
4
Q
cornea
A
A clear covering that protects the eye and begins to focus the incoming light
5
Q
pupil
A
A small opening in the centre of the eye
6
Q
iris
A
The coloured part of the eye that controls the size of the pupil by constricting or dilating in response to light intensity
7
Q
lens
A
A structure that focuses the incoming light on the retina
8
Q
retina
A
Cell layer in the back of the eye containing photoreceptors.
9
Q
visual accomodation
A
The process of changing the curvature of the lens to keep the light entering the eye focused on the retina
10
Q
nearsighted
A
When the focus is in front of the retina
11
Q
farsighted
A
When the focus is behind the retina
12
Q
optic nerve
A
A collection of millions of ganglion neurons that sends vast amounts of visual information, via the thalamus, to the brain
13
Q
rods
A
Photoreceptors of the retina sensitive to low levels of light. Located around the fovea.
- 120 million in each eye
14
Q
cones
A
Photoreceptors of the retina sensitive to color. Located primarily in the fovea.
15
Q
fovea
A
The central point of the retina
16
Q
Margaret Livingstone (2000) on Mona Lisa
A
She smiles until you look at her mouth, and then it fades
17
Q
blind spot
A
A hole in our vision that is created because there are no photoreceptor cells at the place where the optic nerve leaves the retina
18
Q
feature detector neurons
A
Specialized neurons, located in the visual cortex, that respond to the strength, angles, shapes, edges, and movements of a visual stimulus
19
Q
hue
A
The shade of a colour
20
Q
trichromatic colour theory
A
The colour we see depends on the mix of the signals from the three types of cones
21
Q
color blindness
A
The inability to detect green and/or red colours
22
Q
opponent process theory
A
Proposes that we analyze sensory information not in terms of three colours but rather in three sets of “opponent colours”: red-green, yellow-blue, and white-black
23
Q
gestalt
A
A meaningfully organized whole
- whole is more than the sum of its parts
24
Q
Depth perception
A
ability to perceive three-dimensional space and to accurately judge distance.
25
Psychologists Eleanor Gibson and Richard Walk (1960)
14-month-old infants by placing them on a visual cliff
26
visual cliff
A mechanism that gives the perception of a dangerous drop-off, in which infants can be safely tested for their perception of depth
27
depth cues
Messages from our bodies and the external environment that supply us with information about space and distance
28
binocular depth cues
Depth cues that are created by retinal image disparity — that is, the space between our eyes — and which thus require the coordination of both eyes
29
convergence
The inward turning of our eyes that is required to focus on objects that are less than about 50 feet away from us
30
accomodation
Helps determine depth
31
monocular depth cues
Depth cues that help us perceive depth using only one eye
32
beta effect
The perception of motion that occurs when different images are presented next to each other in succession
33
phi phenomenon
We perceive a sensation of motion caused by the appearance and disappearance of objects that are near each other
34
Describe the transduction of somatosensory signals: The properties of the receptor types as well as the difference in the properties of C-afferents and A-afferents and what functions these are thought to have.
Describe the social touch hypothesis and the role of affective touch in development and bonding.
Identify the key structures of the eye and the role they play in vision.
Summarize how the eye and the visual cortex work together to sense and perceive the visual stimuli in the environment, including processing colours, shape, depth, and motion
35
sensory modalities
A type of sense; for example, vision or audition.
36
unimodal stimuli
Of or pertaining to a single sensory modality.
37
multimodal
Of or pertaining to multiple sensory modalities.
38
define integration
The process by which the perceptual system combines information arising from more than one modality.
39
superadditive effect of multisensory integration
(multisensory enhancement)
The finding that responses to multimodal stimuli are typically greater than the sum of the independent responses to each unimodal component if it were presented on its own.
40
Principle of Inverse Effectiveness
The finding that, in general, for a multimodal stimulus, if the response to each unimodal component (on its own) is weak, then the opportunity for multisensory enhancement is very large. However, if one component—by itself—is sufficient to evoke a strong response, then the effect on the response gained by simultaneously processing the other components of the stimulus will be relatively small.
41
multimodal convergeance zones
Regions in the brain that receive input from multiple unimodal areas processing different sensory modalities.
42
superior colliculus
involved in the “orienting response,” which is the behavior associated with moving one’s eye gaze toward the location of a seen or heard stimulus.
43
receptive field
The portion of the world to which a neuron will respond if an appropriate stimulus is present there.
44
crossmodal receptive fields
A receptive field that can be stimulated by a stimulus from more than one sensory modality.
45
crossmodal stimuli
A stimulus with components in multiple sensory modalties that interact with each other.
46
spatial principle of multisensory integration
The finding that the superadditive effects of multisensory integration are observed when the sources of stimulation are spatially related to one another.
47
unimodal cortex
A region of the brain devoted to the processing of information from a single sensory modality.
48
primary visual cortex
Area of the cortex involved in processing visual stimuli.
49
primary auditory cortex
Area of the cortex involved in processing auditory stimuli.
50
multimodal phenomena
Effects that concern the binding of inputs from multiple sensory modalities.
51
crossmodal phenomena
Effects that concern the influence of the perception of one sensory modality on the perception of another.
52
Principle of Inverse Effectiveness:
The advantage gained by audiovisual presentation was highest when the auditory-alone condition performance was lowest
53
McGurk effect
An effect in which conflicting visual and auditory components of a speech stimulus result in an illusory percept.
watch them lips:
gaga or dada
54
rubber hand illusion
The false perception of a fake hand as belonging to a perceiver, due to multimodal sensory information.
55
double flash illusion
The false perception of two visual flashes when a single flash is accompanied by two auditory beeps.
56
the perception of collisions between two circles (called “balls”)
The tendency to perceive two circles as bouncing off each other if the moment of their contact is accompanied by an auditory stimulus.
57
Rosenblum, Miller, and Sanchez (2007)
Experiments have demonstrated that by simply observing a speaker, with no auditory information, we can gather important clues about the actual sound of their voice
58
When a stimulus is presented in a neuron’s ______, that neuron responds by increasing or decreasing its firing rate.
rceptive field
59
Sumby and Pollack (1954)
found that the influence of visual cues on interpretation of an auditory stimulus was most effective when the background noise was loud.
60
Define the basic terminology and basic principles of multimodal perception.
Describe the neuroanatomy of multisensory integration and name some of the regions of the cortex and midbrain that have been implicated in multisensory processing.
Explain the difference between multimodal phenomena and crossmodal phenomena.
Give examples of multimodal and crossmodal behavioral effects.
61
pupil
Small opening in the center of the eye
62
iris
The coloured part of the eye that controls the size of the pupil by constricting or dilating in response to light
63
cornea
A clear covering that protects the eye and begins to focus the incoming light
64
lens
A structure that focuses the incoming light on the retina
65
Visual accommodation
The process of changing the curvature of the lens to keep the light entering the eye focused on the retina
- Flatten for far focus, rounded for nearby!
66
blindspot
A hole in our vision that is created because there are no photoreceptor cells at the place where the optic nerve leaves the retina
67
optic nerve
A collection of millions of ganglion neurons that sends vast amounts of visual information, via the thalamus, to the brain
➤ Optic nerve from each eye projects to
the visual area of the thalamus on both
the ipsilateral (same) side and
contralateral (opposite) side.
➤ From there, the visual input is processed
by visual cortex the ipsilateral side
➤ However, our visual cortex processes
both eyes separately, and in parallel.
68
ventral pathways
"what" pathways
69
dorsal pathways
"where" pathways
70
Agnosia
Loss of the ability to perceive stimuli
71
rods
Photoreceptors of the retina sensitive to low levels of light. Located around the fovea.
72
cones
Photoreceptors of the retina sensitive to color. Located primarily in the fovea.
The visible spectrum of light (400 - 700 nm)
73
trichromatic theory
Theory proposing color vision as influenced by three different cones responding preferentially to red, green and blue.
74
Opponent process theory
Evidence that some neurons in the retina
respond antagonistically to different colors!
➤ e.g. excited by red, inhibited by green
➤ Racing someone after they've run a marathon
75
GESTALT PRINCIPLES
Gestalt refers to "a meaningfully organized whole"
...or, the idea that a whole is more than just the sum of its parts.
Our brains take individually meaningless components and try to assemble or organize
them into something that makes sense to us
76
Types of Gestalt principles
Figure-ground - We structure input so that we always see a figure (image) against a ground (background).
Similarity - Stimuli that are similar to each other tend to be grouped together.
Proximity - We tend to group nearby figures together.
Continuity - We tend to perceive stimuli in smooth, continuous ways rather than in more discontinuous ways.
Closure - We tend to fill in gaps in an incomplete image to create a complete, whole object.
77
binocular disparity
Difference in images processed by the left and right eyes
78
binocular vision
Our ability to perceive 3D and depth because of the difference between the images on our retinas
79
binocular depth cue - convergence
The inward turning of our eyes that is required to focus on objects that are less than about 50 feet away from us
80
binocular depth cue - accommodation
Changes of the curvature of the lens to see far or close objects. Information relayed from the muscles in the eye helps us determine distance.
81
DEPTH CUES (MONOCULAR)
position
relative size
linear perspective
light and shadow
interposition
aerial perspective
82
multimodal perception
The effects that concurrent stimulation in more than one sensory modality has on the perception of events and objects in the world.
83
integation
The process by which the perceptual system combines information arising from more than one modality.
84
Brocea's area
production of speech
85
Werniche's area
understanding of speech
86
Multisensory convergence zones
Regions in the brain that receive input from multiple unimodal areas processing different sensory modalities.
87
Cross-modal receptive field
A receptive field that can be stimulated by a stimulus from more than one sensory modality
