Perception Flashcards
Perception
Conscious experience that results from stimulation of the senses.
Inverse projection problem
Task of determining the object that caused a particular image on the retina.
Transitional probabilities
In speech, the likelihood that one speech sound will follow another within a word.
Demonstrated by Saffran and coworkers (1996) with experiment with infants.
Top-down processing
Processing that involves a person’s knowledge or expectations. This type of processing has also been called knowledge-based processing.
Knowledge and inference are important aspects. Brains essentially making predictions.
Bottom-up processing
Processing that starts with information received by the receptors. This type of processing is also called data-based processing.
Viewpoint invariance
The ability to recognize an object seen from different viewpoints.
Speech segmentation
The process of perceiving individual words within the continuous flow of the speech signal.
Statistical learning
The process of learning about transitional probabilities and about other characteristics of language. Statistical learning also occurs for vision, based on learning about what types of things usually occur in the environment.
Research has shown that infants as young as 8 months of age are capable of statistical learning.
Gestalt psychologist
A group of psychologists who proposed principles governing perception, such as laws of organization, and a perceptual approach to problem solving involving restructuring.
Principles of perceptual organisation
Rules proposed by the Gestalt psychologists to explain how small elements of a scene or a display become perceptually grouped to form larger units. These “laws” are described as “heuristics” in this book.
Likelihood principle
Part of Helmholtz’s 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.
Apparent movement
An illusion of movement perception that occurs when stimuli in different locations are flashed one after another with the proper timing.
Unconscious inference
Helmholtz’s idea that some of our perceptions are the result of unconscious assumptions that we make about the environment. See also Likelihood principle.
Principle of good continuation
Law of perceptual organization stating that points that, when connected, result in straight or smoothly curving lines are seen as belonging together. In addition, lines tend to be seen as following the smoothest path.
Principle of simplicity
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. Also called the law of good figure and the law of simplicity
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. Also called the law of good figure and the law of simplicity.
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.
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.
Principle of similarity
Law of perceptual organization that states that similar things appear to be grouped together.
Oblique effect
The finding that vertical and horizontal orientations can be perceived more easily than other (slanted) orientations.
Prior probability
A person’s initial belief about the probability of an outcome.
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.
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.
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).
Mathematical procedures.
Semantic regularities
Characteristics associated with the functions carried out in different types of scenes. For example, food preparation, cooking, and perhaps eating occur in a kitchen.
Likelihood
In Bayesian inference, the extent to which the available evidence is consistent with the outcome.
Theory of natural selection
Darwin’s theory that characteristics that enhance an animal’s ability to survive and reproduce will be passed on to future generations.
Ventral pathway
The pathway from the visual cortex in the occipital lobe to the temporal lobe. This is also known as the what pathway.
Landmark discrimination problem
Problem in which the task is to remember an object’s location and to choose that location after a delay. Associated with research on the where processing stream.
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.
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.
What pathway
Neural pathway, extending from the occipital lobe to the temporal lobe, that is associated with perceiving or recognizing objects. Corresponds to the perception pathway.
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.
Dorsal pathway
Pathway that extends from the visual cortex in the occipital lobe to the parietal lobe. This is also known as the where pathway.
Mirror neurons
Neurons in the premotor cortex, originally discovered in the monkey, that respond both when a monkey observes someone else (usually the experimenter) carrying out an action and when the monkey itself carries out the action. There is also evidence for mirror neurons in humans.
Mirror neuron system
A network of neurons in the brain that have mirror neuron properties.
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.
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.
Direct pathway model
Model of pain perception that proposes that pain signals are sent directly from receptors to the brain.
Size-weight illusion
When a person is presented with two similar objects that are the same weight but different sizes, the larger one seems lighter when they are lifted together.
Placebo
A pill or procedure that patients believe delivers active ingredients (usually pain killers), but which contains no active ingredient.
Placebo effect
Decrease in pain from a procedure or substance that delivers no active ingredient.
Four conceptions of object perception
Helmholtz’s unconscious inference,
the Gestalt laws of organization, regularities in the environment, and Bayesian inference.
Gestalt laws emphasis bottom-up processing, the other three emphasis top-down processing.
Leslie Ungerleider and Mortimer Mishkin
(1982) studied how removing part of a monkey’s brain affected its ability to identify an object and to determine the object’s location.
The two types of discrimination tasks used by Ungerleider and Mishkin.
(a) Object discrimination: Pick the correct shape. Lesioning the temporal lobe makes this task difficult. (what pathway)
(b) Landmark discrimination: Pick the food well closer to the cylinder. Lesioning the parietal lobe makes this task difficult. (Where pathway).
David Milner and Melvyn Goodale
(1995) used the neuropsychological approach (studying the behavior of people with brain damage) to reveal two streams, one involving the temporal lobe and the other involving the parietal lobe.
Demonstrated that there is one mechanism for judging orientation and another for coordinating vision and action.
Milner and Goodale suggested that the pathway from the visual cortex to the temporal lobe (which was damaged in D.F.’s brain) be called the perception pathway (what) and the pathway from the visual cortex to the parietal lobe (which was intact in D.F.’s brain) be called the action pathway (Where) (also called the how pathway because it is associated with how the person takes action).
G. di Pelligrino and coworkers
- Investigating how neurons in the monkey’s premotor cortex fired as the monkey performed an action like picking up a piece of food.
What was so unexpected was that the neurons that fired to observing the experimenter pick up the food were the same ones that had fired earlier when the monkey had picked up the food.
Led to discovery of mirror neurons.
Mario Iacoboni and coworkers
- Three versions of the film, all showing the same motion of a hand picking up a cup. Version 1 showed a hand reaching to pick up a full cup of coffee from a neatly set up table, with food on a plate. Version 2 showed the same motion but the cup was on a messy table, the food was eaten, and the cup was empty. Version 3 showed the hand picking up an isolated cup.
Based on the increased activity for the two intention films, Iacoboni concluded that the mirror neuron area is involved with understanding the intentions behind the actions shown in the films.
Mirror neurons, according to Iacoboni, code the “why” of actions and respond differently to different intentions.
Jenny Saffran
- Saffran’s experiment has shown that 8-month-old infants are sensitive to transitional probabilities in language.
When tasked with identifying items in a particular scene, compared to humans a computer?
Has less memory.
Perception is to memory as _____ is to _____.
create; retrieve
Gestalt psychologists rejected the structuralist perspective because it presented human perception as a?
Puzzle
Thomas Bayes stated that human perception of objects is based on the combination of which two concepts?
priors and likelihood
