Midterm 2 Flashcards
What is visual scanning?
Looking from one place to another
Each time you briefly paused on one face you were making a __
Fixation
When you move your eye to observe another face, you were making a __
Saccadic eye movement (rapid jerky movement)
What is overt attention and covert attention?
Overt: Attention that involves looking DIRECTLY at the attended object
Covert: Attention without looking i.e. looking at something in our peripheral vision
__ refers to physical properties such as color, contrast, movement, and orientation that makes a particular object or location conspicuous
Stimulus salience
When attention due to stimulus salience causes an involuntary shift of attention, this shift is called __
Attentional capture i.e. a bright flash, or a loud noise
Top-down processing is also associated with __ - an observer’s knowledge about what is contained in typical scenes
Schemas
What is spatial attention?
Attention to a specific location
Posner interpreted that the result as showing that information processing is more effect at __
The place where attention is directed
–> “attention is like a spotlight or zoom lens that improves processing when directed toward a particular location
The faster responding that occurs when enhancement spreads within an object is called the __
Same-object advantage
Being unaware of clearly visible stimuli is __, and the difficulty in DETECTING CHANGES is called __
Inattentional blindness; change blindness
Load theory of attention involves two key concepts:
1) Perceptual capacity
2) Perceptual load
__ refers to the idea that a person has a certain capacity that can be used for carrying out perceptual tasks
Perceptual capacity
__ is the amount of a person’s perceptual capacity needed to carry out a particular perceptual task
Perceptual load
__ is the process by which features such as color, form, motion, and location are combined to create our perception of a coherent object
Binding
__ tackles the question of how we perceive individual features as part of the same object
Feature integration theory
In the feature integration theory, the first step in processing an image of an object is the preattentive stage, where:
Objects are analyzed into separate features
i.e. rolling red ball would be analyzed into the features color (red), shape (round), movement (rolling to the right)
What is Balint’s syndrome?
An inability to focus attention on individual objects
What is akinetopsia?
Blindness to motion
Perception of motion when there actually is none is called __
Illusory motion
__ occur when viewing a moving stimulus for 30-60 seconds causes a stationary stimulus to appear to move
Motion aftereffects
i.e. waterfall illusion - look at a waterfall and then look somewhere else and the stationary view will appear moving up
The fact that everything moves at once in response to movement of the observer’s eyes or body is called __
Global optic flow
__, which results in neurons that fire to movement in one direction
Reichardt detector
__ occurs when an image moves across receptors in the retina, as when Jeremy walks across Maria’s field of view while she stares straight ahead
Image displacement signal (IDS)
__ occurs when a signal is sent from the brain to the eye muscles. This signal occurs when Maria moves her eyes to follow Jeremy as he walks across the room
Motor signal (MS)
__ is a copy of the motor signal that, instead of going to the eye muscles, is sent to a different place in the brain
Corollary discharge signal (CDS)
According to the corollary discharge theory, the brain contains a structure or mechanism called the __ that receives both the IDS and the CDS
Comparator
__ indicates the degree to which the dots move in the same direction
Coherence
Viewing only a small portion of a larger stimulus can result in misleading information about the direction in which the stimulus is moving is called the __
Aperture problem
__ is apparent movement tends to occur along the shortest path between two stimuli
Shortest path constraint
When a still picture depicts an action involving motion, it is called __
Implied motion
The idea that the motion depicted in a picture tends to continue in the observer’s mind is called the __
Representational momentum
__ is defined as a segment of time at a location that is perceived to have a beginning and an ending; __ is the point in time when one event ends and another begins
Event; event boundary
Damage to various modules along the dorsal stream can impair the perception of motion. This is called __
Motion Agnosia (Akinetopsia)
What is self-motion?
Images move across the retina but object motion is not perceived
What is real motion?
Object is physically moving
What is apparent motion?
Still images presented in rapid succession induces the perception of motion. We CANNOT tell the difference between apparent and real motion
When some wavelengths are reflected more than others, it is a process called __
Selective reflection
__ is when only some wavelengths pass through the object or substance
Selective transmission
Because mixing lights involves adding up the wavelengths of each light in the mixture, mixing lights is called __
Additive color mixture
Because each blob of paint absorbs wavelengths and these wavelengths are still absorbed by the mixture, mixing paints is called __
Subtractive color mixture
When two physically different stimuli are perceptually identical, it is called __, and the two identical fields in a color-matching experiment are called __
Metamerism; metamers
The __ states that once a photon of light is absorbed by a visual pigment molecule, the identity of the light’s wavelength is lost
Principle of univariance (receptor only knows total amount absorbed, NOT wavelength)
What is a unilateral dichromat?
A person with trichromatic vision in one eye and dichromatic vision in the other
__ is an effect that occurs when surrounding an area with a color changes the appearance of the surrounded area i.e. a red afterimage surrounds a white area, and causes the white area to look green
Simultaneous color contrast
The __ states that color vision is caused by opposing responses generated by blue and yellow, and by red and green
Opponent-process theory of color vision
__ is when we perceive the colors of objects as being relatively constant even under changing illumination
Color constancy
The fact that we see whites, grays, and blacks as staying about the same shade under different illuminations is called __
Lightness constancy
__ is the proportion of this light that the object reflects into our eyes
Reflectance
What is the ratio principle?
As long as the ratio remains the same, the perceived lightness will remain the same
A __ is an edge where the reflectance of two surfaces changes
Reflectance edge
An __ is an edge where the lighting changes
Illumination edge
The fuzzy border at the edge of the shadow is called the shadow’s __
Penumbra
The __ molecule is responsible for bitter taste, and the __ molecule is responsible for sweet taste
Quinine; sucrose
__ is a cue that one object is in front of another / when one object hides or partially hides another from view
Occlusion
This cue is based on our ability to sense the position of our eyes and the tension in our eye muscles
Oculomotor
__ are sources of depth information that can be depicted in a picture, such as illustrations in a book or an image on the retina
Pictorial cues
When you look down parallel railroad tracks that appear to converge in the distance, you are experiencing __
Perspective convergence
We use the cue of __ when we judge distance based on our prior knowledge of the sizes of objects
Familiar size
__ occurs when distant objects appear less sharp than nearer objects and often have a slight blue tint
Atmospheric perspective
__ are when elements that are equally spaced in a scene appear to be more closely packed as distance increases
Texture gradient
__ occurs when we move, nearby objects appear to glide rapidly past us, but more distant objects appear to move more slowly i.e. looking outside the window of a moving train
Motion parallax
__ are the differences in the images on the left and right retinas
Binocular disparity
__ are points on the retina that overlap if the eyes are superimposed on each other
Corresponding retinal points
Objects that fall on corresponding points are located on a surface called the __
Horopter
The degree to which these objects DEVIATE from falling on corresponding points is called __
Absolute disparity
The difference in absolute disparities of objects in a scene is called __, which remains the same as an observer looks around a scene. It helps indicate where objects in a scene are located relative to one another
Relative disparity
__ is the angle of an object relative to the observer’s eye
Visual angle
What is Emmert’s law?
The farther away an afterimage appears, the larger it will seem
When two objects are the same size on the page, and have the same visual angle, but the one on top appears longer, it is called the __
Ponzo illusion
The __ causes two people of equal size to appear very different in size
Ames room
Another theory of the moon illusion is the __, which states that the moon appears smaller when it is surrounded by larger objects
Angular size contrast theory
Focus of expansion is __
Where you are heading (no flow)
