Cognitive-Chapter 3-Perception Flashcards
Give an example that illustrates the need to go beyond pattern of light and dark in a scene to describe the process of perception
We can easily describe the relation between parts of a city scene, but it is often challenging to indicate the reasoning that led to the description.
Attempts to program computers to recognize objects have shown…
How difficult it is top gram computers to perceive at a level comparable to humans
What are the difficulties facing computers when trying to perceive at a level comparable to humans?
- The stimulus on the receptors is ambiguous, as demonstrated by inverse projection problem
- Objects in a scene can be hidden or blurred
- Objects look different from different viewpoints
Perceptions starts with…
Bottom up processing, which involves stimulation of the receptors, creating electrical signals that reach the visual receiving area of the brain
Perception also involves…
Top down processing which originates in the brain
Examples of top down processing:
The multiple personalities of a blob and finding faces in a landscape
How knowledge of a language makes it possible to perceive individual words
How the perception of pain is influenced by things other than the pain stimulus
The idea that perception depends on knowledge was proposed by…
Helmholtz’s theory of unconscious inference
The Gestalt approach to perception proposed…
A number of laws of perceptual organization, which were based on how stimuli usually occur in the environment
Regularities in the environment are…
Characteristics of the environment that occur frequently. We take both physical and semantic regularities into account when perceiving.
Bayesian inference is
A mathematical procedure for determine what is likely to be “out there”; it takes into account a person’s prior beleifs about a perceptual outcome and the likelihood of that outcome based on additional evidence.
the four approaches to object perception
- unconscious inference
- Gestalt
- Regularities
- Bayesian
Of the 4 approaches to perception this approach relies more on bottom up processing than others
Gestalt
Modern psychologists have suggested. Connection between past experience and…
The Gestalt principles
One of the basic operating principles of the brain is…
That is contains some neurons that respond best to things that occur regularly in the environment
Experience-dependent plasticity is
One of the mechanisms responsible for creating neurons that are tuned to respond to specific things in the environment
The experiment in which kittens reared in vertical or horizontal environments and Greeble experiment support
Experience-dependent plasticity
What are linked?
Perceiving and taking action
Example supporting perception and taking action being linked
Movement of an observer relative to an object provides information about the object
There is a constant coordination between perceiving an object and
Taking action
Ex: seeing a cup and picking it up
Research involving brain ablation in monkeys and neuropsychological studies of the behavior of people with brain damage have revealed…
Two processing pathways in the cortex that work together to coordinate perception and action
- A pathway from the occipital lobe to the temporal lobe is responsible for perceiving objects
- A pathways from the occipital lobe to the parietal lobe is responsible for controlling actions toward objects
Recordings from single neurons in the hippocampus of epilepsy patients have discovered…
Neurons that respond both when a visual stimulus is being perceived and when it is being remembered later.
Action pathway
Neural pathway extending from the occipital lobe to the parietal lobe that is associated with neural processing that occurs when people take action. Corresponds to the Where pathway.
Apparent movement
An illusion of movement perception that occurs when stimuli in different locations are flashed one after another with the proper timing.
Bayesian inference
The idea that our estimate of the probability of an outcome is determined by the prior probability (our initial belief) and the likelihood (the extent to which the available evidence is consistent with the outcome)
Bottom-up processing
Processing that starts with information received by the receptors. Aka data-processing.
Brain-ablation
A procedure in which a specific area is removed from an animal’s brain. It is usually done to determine the function of this area by assessing the effect on the animal’s behavior.
Direct-pathway model
Model of pain perception that proposes that pain signals are sent directly from receptors to the brain
Experience-dependent plasticity
A mechanism that causes and organism’s neuron’s to develop so they respond best to the type of stimulation to which the organism has been exposed
Gestalt psychologists
A group of psychologists who proposed principles governing perception, such as laws of organization, and a perceptual approach to problem solving involving restructuring.
Inverse projection problem
Task of determining the object that cause a particular image on the retina
Law of pragnanz
Law of perceptual organization that states that every stimulus pattern is seen in such a way that the resulting structure is as simple as possible. Aka the law of good figure or law of simplicity
Landmark of discrimination problem
Problem in which the task to remember an object’s location and to choose that location after a delay. Associated with research on the Where processing stream.
Light from above assumption
The assumption that light is coming from above. This is a heuristic that can influence how we perceive three-dimensional objects that are illuminated.
Likelihood
In Bayesian inference, the extent to which the available evidence is consistent with the outcome
Likelihood principle
Part of the helmholtz theory of unconscious inference that states that we perceive the object that is most likely to have caused the pattern of stimuli we have received.
Object discrimination problem
A problem in which the task is to remember an object based on its shape and choose it when presented with another object after a delay. Associated with research on the What processing stream
Oblique effect
The finding that vertical and horizontal orientations can be perceived more easily than other (slanted) orientations.
Perception
Conscious experience that results from stimulation of the senses
Perception pathway
Neural pathway, extending from the occipital lobe to the temporal lobe that is associated with perceiving or recognizing objects. Corresponds to the What pathway
Physical regularities
Regularly occurring physical properties of the environment. For example: there are more vertical and horizontal orientations in the environment than oblique/angled orientations.
Placebo
A pill or procedure that patients believe delivers active ingredients but which contains no active ingredients
Placebo effect
Decrease in pain from a procedure or substance that delivers no active ingredients
Principle of good continuation, good figure, principle of similarity, of simplicity
Law of perceptual organization stating that when connects result in straight or smoothly curving lines are seen as belonging together. In addition, lines tend to be seen as following the smoothest path.
Prior
A person’s initial belief about the probability of an outcome
Prior probability
Same as prior
Regularities in the environment
Characteristics of the environment that occur frequently. For example, blue is associated with open sky, landscapes are often green and smooth, and verticals and horizontals are often associated with buildings
Scene schema
A person’s knowledge about what is likely to be contained in a particular scene. This knowledge can help guide attention to different areas of the scene. For example, knowledge of what is usually in an office may cause a person to look toward the desk to see the computer
Semantic regularities
Characteristics associated with the functions carried out in different types of scenes. For example, food preparation, cooking and perhaps eating occur in the kitchen
Speech segmentation
The process of perceiving individual words within the continuous flow of the speech signal.
Theory of natural selection
Darwin’s theory that characteristics that enhance an animals ability to survive and reproduce will be passed on to future generations
Top down processing
Processing that involves a person’s knowledge or expectations. This type of processing has also been called knowledge-based processing.
Unconscious inference
Helmholtz’ sides that some of our perceptions are the result of unconscious assumptions that we make about the environment.
Viewpoint invariance
The ability to recognize an object seen from a different viewpoint
The What pathway
The neural pathway extending from the occipital lobe to the temporal lobe that is associated with perceiving or recognizing objects. Corresponds to the perception pathway
the Where pathway
neural pathway, extending from the occipital lobe to the parietal lobe that is associated with neural processing that occurs when people locate objects in space. Roughly corresponds to the action pathway.
The example of a person running on the beach and having coffee later illustrates…
How perception can change based on new information, how perception can be based on principles that a re related to past experiences, how perception is a process, and how perception and action are connected.
