exam 2 Flashcards
list the steps in color perception in the correct order
Detection, discrimination, appearance
Which photoreceptors are most active when looking at a blue sky?
S-cones. S-cones are specialized to receive short wavelengths. Blue is a short wavelength.
Which color pair is farthest apart in wavelength?
Blue and red
The principle of univariance refers to the fact that
an infinite set of different wavelength–intensity combinations can elicit the same response from a single type of photoreceptor.
_______ are different mixtures of wavelengths that look identical.
Metamers
According to the principle of univariance, which genetic difference in color vision would cause someone to be truly color-blind?
Cone monochromat
When adding colors, blue and yellow create white through _______ color mixing and create green through _______ color mixing.
additive; subtractive
According to the trichromacy theory, the color of any light is defined in our visual system..
by the relationships among three numbers of a set.
correctly list the color-opponent pairs coded by the visual system
Blue versus yellow; red versus green; black versus white
In the hue cancellation experiments described in the textbook, if the starting color were too reddish, you would add
green
_______ is the inability to perceive colors due to damage to the central nervous system.
Achromatopsia
______ is the idea that basic perceptual experiences may be determined in part by the cultural environment
Cultural relativism
example of Cultural relativism
there are only a dozen basic colors, and other colors may not have a name if that culture does not recognize them as distinct categories.
A(n) _______ is an individual who suffers from color blindness that is due to the absence of M-cones.
deuteranope
What is the term for an inability to name objects or colors despite being able to see and recognize them?
Anomia
Which term describes the experience of seeing colors when hearing music or perceiving a letter as having a color, even if it is printed in black ink?
Synesthesia
____ is a color perception effect in which the color of one region induces the opponent color in a neighboring region.
Color contrast
____ is a color perception effect in which two colors bleed into each other, each taking on some of the chromatic quality of the other.
Color assimilation
_____ is the difference between the two retinal images of the same scene and is the basis of stereopsis.
Binocular disparity
A(n) _______ is a visual image seen after the stimulus has been removed.
afterimage
The tendency of a surface to appear the same color under a fairly wide range of illuminations is known as
color constancy
What is the function relating the wavelength of light to the percentage of that wavelength that is reflected from the surface
Spectral reflectance function
Which of the following is not a monocular cue?
Convergence
When an artist paints trees on a landscape extending into the distance, she distributes the trees vertically to simulate _______, and makes trees that are farther away smaller, simulating _______.
relative height; relative size
Suppose you are looking at a road that recedes into the distance. Which depth cue describes the way the edges of the road seem to converge in the retinal image?
Linear perspective
_____ provide(s) precise quantitative information about distance in the third dimension.
Metrical depth cues
which depth cue can provide information about precise distance from the observer?
Familiar size
Which depth cue gives you the most precise metrical information about object distance?
Stereopsis
______ is an important depth cue that comes into play during head movements or while moving through an environment.
Motion parallax
What is Panum’s fusional area?
The small area around the horopter where images from each eye are fused into a single image.
The difference between crossed disparity and uncrossed disparity is that crossed disparity involves objects that are _______ the plane of fixation, while uncrossed disparity involves objects that are _______ the plane of fixation
in front of; behind
The problem of determining which bit of the image in the left eye should be matched with which bit of image in the right eye is known as the
correspondence problem.
Virtual reality headsets have a separate display for each eye. What is another technical name for such a device?
Stereoscope
A random dot stereogram contain
no monocular cues.
If you are able to free-fuse a display and get it to appear in focus but not perceive any apparent depth, then you might be
stereoblind
_______ is based on the idea that prior knowledge could influence the estimates of the probability of a current event.
The Bayesian approach
_______ is a measure of the smallest binocular disparity that can generate a sensation of depth.
Stereoacuity
_______ refers to the presentation of two stimuli, one to each eye.
Dichoptic
Attention is generally thought of as
consisting of a family of selection mechanisms
If the two eyes are not aligned properly the brain tends to ignore information from one eye. This phenomenon is known as
suppression
_____ attention involves restricting processing to a subset of the possible stimuli.
Selective
In a _______ task, the target is defined by the presence of a single feature, or attribute, such as a salient color or orientation.
feature search
A _______ is a stimulus that might indicate where (or what) a subsequent stimulus might be.
cue
This is the amount of time between the onset of one stimulus and the onset of a second stimulus.
Stimulus Onset Asynchrony (SOA)
When measuring reaction time (RT), we measure the
time from the onset of a stimulus to a response
In an “efficient” search, the slope of the function relating _______ time to set size is about 0 ms/item.
reaction
In a(n) _______ search, multiple stimuli are processed at the same time.
parallel
If you are searching for your car keys and you restrict your attention to horizontal surfaces near the front door, you are using
scene-based guidance
According to Treisman’s feature integration theory
a limited set of features can be processed in parallel preattentively
The _______ problem refers to the challenge of tying different attributes of visual stimuli (e.g., color, orientation, motion), which are handled by different brain circuits, to the appropriate object so that we perceive a unified object (e.g., blue, horizontal, moving to the left).
binding
Seeing a blue cup when the cupboard contains blue mugs and yellow cups, but no blue cups, is referred to as a(n)
illusory conjunction
Research suggests that you could reduce the magnitude of your attentional blink by
playing action video games
The _______ is the difficulty in perceiving and responding to the second of two target stimuli amid a rapid stream of stimuli if the observer has responded to the first target stimulus within 200 to 500 ms before the second stimulus is presented.
attentional blink
Suppose you are looking at an image of a face superimposed on a house. What would we expect to happen in terms of neural activity if you are attending to the house?
The PPA becomes more active
The average and distribution of properties, like orientation or color, over a set of objects or a region in a scene are called the _______ of the scene and is/are computed by the _______ pathway.
ensemble statistics; nonselective
____ describes the structure of a scene without reference to the identity of specific objects in the scene.
Spatial layout
Change blindness is a failure to
notice a change between two scenes
The impression of smooth motion that comes from the rapid alternation of objects appearing in nearby locations in rapid succession is
apparent motion.
__ refers to the failure to notice—or at least to report—a stimulus that would be easily reportable if it were attended.
Inattentional blindness
_ is the illusion that a stationary object is moving and occurs after prolonged exposure to a moving object.
Motion aftereffect
that a strong motion aftereffect is obtained when one eye is adapted and the other is tested suggests that
the motion aftereffect occurs in a part of the visual system where information from the two eyes is combined.
Which brain region is most specialized for motion processing?
Middle temporal area (area V5/MT)
Damage to area MT/V5 can result in this neurological disorder, in which you no longer perceive motion.
Akinetopsia
What is the “aperture problem”?
Local edge motion seen through a single aperture is ambiguous.
The problem faced by the motion detection system of knowing which feature in Frame 2 corresponds to a particular feature in Frame 1 is known as the _______ problem.
correspondence
_____ is motion of an object that is defined by changes in contrast or texture, but not by luminance.
Second-order motion
____ describes the changing angular positions of points in a perspective image that we experience as we move through the world.
Optic flow
A field of globally moving dots can make stationary targets in the periphery seem to disappear in a phenomenon known as
motion-induced blindness.
What does tau tell you?
Time to collision
The _______ of the brain is important for initiating and guiding eye movements.
superior colliculus
The motion we interpret as people moving around from a few animated dots is called _______ motion.
biological
If you hear a loud noise and rapidly shift your eyes to point in the direction of where the noise came from, which kind of eye movement are you making?
Saccade
The reduction of visual sensitivity that occurs when we make saccadic eye movements is called
saccadic suppression
An area of the visual system that receives one copy of the order issued by the motor system when the eyes move is called
a comparator
The purpose of the comparator is to _______ eye movements.
keep track of which image movements on the retina are due to
Receptive field updating occurs when receptive fields transiently remap towards the point of fixation and
neurons shift their receptive fields just before a saccade.
Which statement about the development of motion perception in humans is false?
Sensitivity to visual motion is fully developed at birth.
true statements about the development of motion perception in humans
- reflexive eye movements to moving targets are present in newborns.
- Sensitivity to global motion matures at about 3–4 years of age.
- V1 neurons in newborns have adult-like sensitivity.
- Sensitivity to motion-defined form and biological motion takes more than three years to develop.
These cells are in the Lateral Geniculate Nucleus
Cone Opponent Cells
Painters use this contrast technique to give mountain ranges in the distance a sense of distance.
Atmospheric/Aerial perspective
In a simple feature search (in contrast to a conjunction search), reaction time remains constant (RT 0) regardless of the number of distracters since the target “pops out” because of this characteristic.
salience
This is a powerful illusion of motion in the visual image caused by prior exposure to motion in the opposite direction
motion aftereffect?
This visual condition, also known as double vision, occurs when the brain receives mismatched images from the two eyes and fails to combine them into a single image.
diplopia
Bilateral V4 damage in Ventral Pathway results in this
Cortical achromatopsia
These are both oculomotor depth cues
accommodation and convergence
This type of search takes people more and more reaction time as the number of features increase.
conjunction search
This visual challenge occurs when only part of a moving object is visible, making it difficult to perceive its true motion
aperture problem
Severe bilateral damage to this area can result in simultanagnosia
Posterior Parietal Lobe area
Simultanagnosia
Inability to perceive multiple objects at once, disrupting scene comprehension. One of 3 main symptoms of Balint’s Syndrome
Any pair of stimuli perceived as matching in color, but having different (nonmatching) spectral power distributions, such as a red-green light mix that looks yellow.
metamers
While walking past a fence, nearby objects like fence posts seem to move quickly across your field of vision, while distant buildings appear to move much slower. This phenomenon helps provide depth information.
motion parallax
This type of attention impairs performance when trying to focus on multiple tasks at once, regardless of how much practice you have.
Divided Attention
This aspect of optical flow remains stationary while everything else moves outward from that point as a person moves through space.
Focus of Expansion
This apparent motion illusion turns a “hole’ into an object.
Phi Phenomenon
This principle explains why a single photoreceptor cannot differentiate between changes in intensity and changes in wavelength, leading to color vision deficiency if only one type of cone is available.
Principle of Univariance
In a random dot stereogram, this process allows you to perceive depth by matching points once between the two retinal images.
correspondence matching/correspondence point matching
You are focused on organizing your papers on your desk into seperate piles, and you fail to notice a mouse on a nearly empty plate that is clearly visible. This is an example of
inattentional blindness
In a study on motion perception, monkeys with lesions to this brain area required ten times as many dots in a correlated dot motion display to correctly identify motion direction.
MT (middle temporal) area
This is the most salient of all features
motion
This term refers to how much energy a light source emits at each wavelength across the visible spectrum—it’s what determines the color quality and appearance of the light.
Spectral Power Distribution/ Distribution of Spectral Density
The region of space, in front of and behind the horopter, within which binocular single vision is possible.
Panum’s Fusional Are
Initiating and guiding reflexive eye movements are controlled mainly by this brain structure
Superior Colliculus
Severe bilateral damage to Media Temporal (MT) area results in this
Akinetopsia
Akinetopsia
inability to perceive motion
The M-Path relies on this since it cannot see color very well
contrast
You can add more lights to cancel out the original light’s color through this process, such as using cyan to cancel red or blue to cancel yellow.
additive color mixing
This term describes the slight difference between the images seen by each eye, which the brain uses to perceive depth.
binocular disparity
These regions in the visual cortex can change in size and location based on attentional demands, focus, and the presence of distracting stimuli.
receptive fields
These rapid, jerky eye movements shift the focus of vision from one point to another, occurring when scanning a scene or reading.
saccades
This phenomenon keeps us from perceiving a blur or smear across the visual field during rapid eye movements by briefly reducing visual sensitivity.
saccadic suppression
When you place a blue square next to a yellow background, this effect makes the blue appear more vivid and distinct.
color contrast
These depth cues, such as occlusion, relative size, and linear perspective, can be perceived using just one eye.
monocular depth cues
This phenomenon occurs when a visual change in a scene goes unnoticed, especially when attention is diverted or focused elsewhere.
change blindness
This type of motion, defined by texture change instead of luminance change, is only seen in the lab
second-order motion
This brain region is involved with perceiving the motion of people and animals.
posterior superior temporal sulcus/ STSp
These have no disparity and therefore can’t contribute to binocular vision.
objects on the horopter/corresponding points
These two vision deficiencies would make it difficult for someone to distinguish between red and green colors.
deuteranopia or protanopia
This theory proposes that while basic visual features like color and shape can be processed without focused attention, binding these features together to perceive a coherent object requires selective attention.
Feature Integration Theory
This phenomenon ensures that the perceived color of objects remains relatively stable under varying lighting conditions.
color constancy
This phenomenon occurs when stationary objects in your visual field disappear from awareness as a result of surrounding motion.
motion-induced blindness
We use this to calculate Time To Collision.
Tau
This approach to perception uses prior knowledge and probabilities to interpret ambiguous sensory information and make predictions about the most likely outcome
Bayesian approach
In scene perception, this attention pathway processes object identity, loosely similar to the ‘what’ pathway in visual processing.
selective pathway
This brain area becomes active when processing complex motion, such as when navigating through your environment while walking.
MST, medial superior temporal area
This phenomenon occurs when a second target is missed if it appears within 200–500 milliseconds after a first target in a rapid stream of stimuli, due to a temporary gap in attention.
attentional blink
This term describes the percentage of light that a surface reflects at each wavelength, helping determine the color we perceive
spectral reflectance/density of reflected light
These do not prioritize any one cue over others across contexts.
Perceptual Committees
This early selection model of attention suggests that information is filtered based on physical attributes before reaching higher levels of processing
Broadbent’s Filter Model
This mechanism explains how the brain uses a copy of motor commands to prevent confusion between actual motion in the environment and motion caused by eye movements.
Corollary Discharge Signal
This is the inability to perceive depth using binocular disparity
stereo blindness
