Chapter 5 Flashcards
To create the description, “ a young boy, is holding a baseball bat” the computer first had to detect the objects in the image, and then match those objects to existing, stored representations of what those objects are
Object recognition
The task of determining the object responsible for a particular image on the retina
Inverse projection problem
The ability to recognize an object seen from different viewpoints
Viewpoint invariance
Scientist that ask “ how are configurations formed from smaller elements?”
Gestalt psychologists
Distinguishing between sensations-elementary processes that occur in response to stimulation of the senses-and perceptions, more complex conscious experiences such as our awareness of objects
Structuralism
Although movement is perceived, nothing is actually moving
Apparent movement
There are actually no physical edges present in a given object or stimulus. Sensations can’t explain _________because there aren’t any sensations along the contours.
Illusory contours
Determines how elements in a scene become grouped together. Starting points for the _________are things that usually occur in the environment
Principles of perceptual organization
Points that, when connected, result in straight or smoothly curving lines, are seen as belonging together, and the lines tend to be seen in such a way as to follow the smoothest path. Objects that are partially covered by other objects are seen as continuing behind the covering object.
Principle of good continuation
A.k.a. principle of good figure, or the principal of simplicity. Every stimulus pattern is seen in such a way that the resulting structure is as simple as possible.
Principle of pragnanz
Similar things appear to be grouped together
Principle of similarity
Things that are near each other appear to be grouped together
Principle of proximity
Things that are moving in the same direction appear to be grouped together
Principle of common fate
Elements that are within the same region of space appear to be grouped together
Principle of common region
A connected region of the same visual properties, such as lightness, color, texture, or motion is perceived as a single unit
Principle of uniform connectedness
When we see a separate object, it is usually seen as a figure that stands out from its background, which is called the ground
Figure-ground segregation
An ambiguous figure in which the perspective easily shifts, so that at certain times specific elements appear to make up a distinct figure, while at others, the same elements appear as an indistinct background
Reversible figure-ground
A term for the phenomenon that a visual border between two image regions is normally perceived to belong to only one of the regions
Border ownership
Determines how an image is segregated into figure and ground
Figural cues
Objects are comprised of individual geometric components, called geons, and we recognize objects based on the arrangement of those geons. Geons are three dimensional shapes, like pyramids, cubes, and cylinders.
Recognition by components (RBC) theory
A view of a real world environment that contains 1) background elements, and 2) multiple objects that are organized in a meaningful way relative to each other and the background
Scene
The perception of a visual stimulus continues for about 250 ms after the stimulus is extinguished. Thus, a picture that is presented for 100 ms will be perceived as lasting about 350 ms.
Persistence of vision
Usually a random pattern that covers the original stimulus, so if a picture is flash for 100 ms followed immediately by a ______, the picture is visible for just 100 ms
Visual masking stimulus
Can be perceived rapidly and are associated with specific types of scenes
Global image features
Characteristics of the environment which occur frequently
Regularities in the environment
Regularly occurring physical properties of the environment
Physical regularities
We usually assume that light is coming from above, because light in the environment, including the sun, and most artificial light, usually comes from above
Light-from-above assumption
In language, ______refers to the meanings of words or sentences. Applied to perceiving sayings, _______refers to the meaning of a scene. This meeting is often related to what happens within the scene.
Semantics
Characteristics associated with activities that are common in different types of scenes
Semantic regularities
Knowledge of what a given scene typically contains
Scene schema
The idea that perception involves inference
Theory of unconscious inference
We perceive the object that is most likely to have caused the pattern of stimuli we have received
Likelihood principle
Our perceptions are the result of unconscious assumptions, or inferences, that we make about the environment
Unconscious inference
The idea that our past experiences help us make informed guesses about what we will perceive
Prediction
Our estimate of the probability of an outcome is determined by two factors 1) prior probability, or simply the prior, which is our initial estimate of the probability of an outcome, and 2) the extent to which the available evidence is consistent with the outcome. The second factor is called the likelihood of the outcome.
Bayesian inference
A theory that describes how the brain uses our past experiences-or our “ priors,” as Bayes put it-to predict what we will perceive
Predictive coding
