Form Perception Flashcards
What describes how we group visual input in certain ways?
Laws of Organization/Grouping Tendencies
aka the Gestalt principles
Are the Gestalt principles innate?
Gestalt psychologists believe these are innate or acquired very rapidly after birth
What is the following Gestalt principle called?
The ability to determine what aspect of a visual scene is part of the figure and what is part of the background
Figure-ground segregation
How do figures look compared to the background?
Figures tend to have distinct borders or edges that give it a perceptible form and is perceived as being in front of the background (which can be formless or made up of multiple forms)
Our ability to segregate figure from background is an __________ process that is guided by cues and influenced by prior EXPERIENCES, BIAS & NEURISTICS
Automated
What is the following Gestalt principle called?
Elements that are close together in space tend to belong together
Proximity
- help with grouping
How does grouping work in regard of proximity?
- Regions of high density as one group due to proximity
- More likely to group objects that are closer together than far apart
What is the following Gestalt principle called?
If there are gaps in the contours of a shape, we tend to fill in those gaps and perceive a whole object
Closure
- we automatically fill in the parts we can’t see to perceive a single object
What is the following Gestalt principle called?
The tendency for us to group together elements that are physically similar
Similarity
- helps with grouping
How does grouping work in regards to similarity?
- We tend to group together objects of the same type
- We tend to see columns of the same elements as belonging together
What is the following Gestalt principle called?
Allows us to perceive a simple, continuous form rather than a combination of awkward forms
Continuity
What is the following Gestalt principle called?
The idea that things that change in the same way should be grouped together
Common fate
- helps with grouping
- explains why we can suddenly see a camouflaged animal once it moves
How does grouping work in regards of common fate?
- objects moving together in the same direction tend to be grouped together
Which method of processing is this?
The features that are present in the stimulus itself guides object recognition
Bottom-up processing
- noticing the stimulus details itself first
What does bottom-up processing compare?
Compare every feature of the stimulus to memory
- you recognize what you see by analyzing the individual features and comparing those features to things with similar features that you have in memory
Which method of processing is this?
Your own beliefs or expectations are the primary influence for determining what you’re seeing
Top-down processing
- using prior knowledge
- needs some input from the stimulus to work
___________ can be primed in top-down processing
Recognition
What is bi-directional activation?
Object recognition occurs when both top-down and bottom-up processing occurs together at once
- the features of the object in combination with our expectations guide object recognition
What does Biederman’s geon theory suggest?
- suggests that we have 36 different geons or simple geometrical forms, stored in memory
What does template theory suggest?
- Suggests that we store many different templates in memory and we compare the object to all the templates in our memory
Differences between the template theory and exemplar theory
- template theory requires an exact match between the object and template in order for recognition to occur
- exemplar theory does not require an exact match for categorization
Template theory
What happens if a template is found? If it is not found?
IF FOUND:
- the object is a familiar object and the person could name it by activating connections to other language areas in the brain
IF NOT FOUND:
- the object is an unfamiliar object and a new template is stored in the memory of this novel object
What does the prototype theory suggest?
- Suggests that we compare objects to our ideal prototype
What does the prototype theory compare?
Comparing novel objects to our internal “best” representation
- does not need to be an exact match between the object and what’s stored in memory
- it’s likely we have more than 1 type of representation for each object
What is the following constancy called?
Our ability to perceive an object as unchanging even though the visual image produced by the object is constantly changing
Perceptual constancy
What is the following constancy called?
An object is perceived to have a constant shape despite the shape of its retinal image changing with shifts in point of view or changes in object position
Shape constancy
eg. a door is perceived as rectangular despite its visual chance when opening
What is the following constancy called?
An object is perceived to be stationary despite changing location on our retina due to body movements
Location constancy
eg. when driving, we don’t perceive the objects to be moving
What is the following constancy called?
An object is perceived to be the same size despite the size of its retinal image varying distance
Size constancy
eg. a person walking away is not perceived as shrinking in size
What is the following constancy called?
An object is perceived to have a constant colour despite different illumination conditions
Colour constancy
eg. a white dog is still recognized even under a red light
What is the following constancy called?
An object is perceived to be the same brightness despite reflecting more or less light onto our retina
Brightness constancy
eg. objects have the same brightness whether in high or low illumination
Existing knowledge provides top-down influence on _________
Perception
Existing knowledge makes sense of changing _______ stimuli
visual
Cues in the scene indicate ____________ constancies
perceptual
________ cues indicate the size of an object relative to its distance
Depth
________ cues indicate the influence of a light on an object’s colour
Colour
Perceptual constancies exist from prior _________ and cues in our _______
Prior knowledge & cues in our scene
Visual illusions arise from ______________ in perception
Ambiguities
The Muller-Lyer illusion misapplies ______ constancy and misinterprets ______
Size & depth
Who is less susceptible to the Muller-Lyer illusion?
Cultures without exposure to right angles
The Ames room manipulates _________ to trick size constancy
Distance
The Ponzo illusion manipulates _________ cues to trick size constancy
Depth
Visual illusions indicate that perception is an ________ process
Active
What is the process in the brain when processing visual input?
Ganglion cells (in retina) –> exit via optic nerve –> optic chiasm –> optic tract –> LGN (lateral geniculate nucleus) –> primary visual area of cortex
Why are some cells in the primary visual cortex called FEATURE-DETECTORS?
B/c they detect features
Visual cortex neuron firing can be affected by the stimulus’s __________, ____________, ___________________
Location
Orientation
Direction of movement
When does each feature detector cell fire maximally?
Each feature detector cell is very specific about what will make it fire the most
- these cells fire maximally to stimuli of a certain shape, size, position and movement
- this defines the receptive field for that cell
What type of cell is the following?
Responds maximally to a bar of a certain orientation in a particular region of the retina
Simple cells
How is the receptive field of simple cells organized?
In an opponent fashion
What is the preferred orientation for simple cells
Horizontally aligned preferred orientation
What type of cell is the following?
Responds maximally to a bar of a certain orientation, regardless of location
Complex cells
- some also respond maximally to a specific direction of movement
- indifferent to the position of the light on its receptive field
- some care about the direction of movement
What type of cell is the following?
Responds maximally to a bar of a particular orientation and direction of movement, ending at specific points within the receptive field
Hypercomplex cell
- receptive fields have a region of inhibition at the end
Why do we have 3 cell types?
B/c it allows the brain to optimally balance the function of each wile consuming the least possible amount of energy
