WEEK 3: Perception Flashcards
Experiences resulting from stimulation of the senses.
Perception
BUP: stands for “__________”
Bottom-Up Processing
The sequence of events from eye to brain.
Bottom-Up Processing (BUP)
Visual Images
- The light entering the eye and the electrical
signals in the brain is crucial for perceiving any object in the environment because of the light, the object is represented in the nervous system.
Bottom-Up Processing (BUP)
TDP: stands for “________”
Top-Down Processing
Processing that originates in the brain, at the top of the perceptual system.
Top-Down Processing (TDP)
Top-Down Processing (TDP)
Perception involves not only our senses, it also includes:
- Knowledge of the environment
- Expectations
- Attention to stimuli
- Experiences
- Memories
Who studied “the multiple personalities of a blob”?
Olivia and Torrabla (2007)
Participants in the study were asked to identify
a blurred object in a scene (the blob).
The multiple personalities of a blob
TRUE or FALSE
The multiple personalities of a blob
Result: blobs in all pictures were identical but
were perceived as different objects (shoe, car, person) depending on the orientation and the context within which they were seen.
TRUE
The Perception of Pain Direct Pathway Model
Pain occurs when receptors in the skin called __________ are stimulated and send their signals in a direct pathway from the skin to the brain (Melzack & Wall, 1965) BUP depends on stimulation of the receptors.
nociceptors
The given situation is an example of:
Athlete finishing the face despite a broken toe, which was only felt after the sprint. You started to feel pain only after you saw or paid attention to the bleeding wound.
The Perception of Pain Direct Pathway Model
_________ pill for painkillers were given to patients with pathological pain where they get real relief.
PLACEBO
Release of _________ ______, a pain reducing neurotransmitter
endogeneous opiods
This is when a person is conditioned to expect a negative response, or to anticipate negative effects from an experience.
NOCEBO
Expectations influence and redirects attention.
Cognitive or Attention Control
Over-reliance on ______, might mean being caught in a fantasy world of hopes, expectations, overlooking the in-your-face reality.
TDP
Over-reliance on _____, might mean ‘seeing the world at face value’.
BUP
You are not being insightful enough. There’s more than what meets the eye.
Over-reliance on BUP
4 Approaches to Object Perception
- Helmholtz’s Theory of Unconscious Inference
- Gestalt Approach
- Regularities in the Environment
- Bayesian Inference
The Physicist who made “Helmholtz’s Theory of Unconscious Inference”
Hermann von Helmholtz (1821-1894)
As 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.
UNCONSICOUS INFERENCE
German word meaning whole.
Gestalt
“The whole is more than the sum of its parts”
Gestalt Principles of Organization
Gestalt’s approach to perception originated in part as a reaction to ___________’s Structuralism
Wilhelm Wundt
Wundt proposed that our overall experience could be understood by combining basic elements of experience called _________.
sensations
TRUE or FALSE
Gestalt Psychologists accepted the idea that perceptions are formed by simply adding sensations.
FALSE; rejected the idea
Proposed several PRINCIPLES OF ________________ to explain the way elements are grouped together to create larger objects.
PERCEPTUAL ORGANIZATION
________ is more than just the pattern of light and dark on the retina.
Visual perception
_________ is determined by specific organizing principles.
Perception
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.
Good Continuation
Objects that are overlapped by other objects are perceived as continuing behind the overlapping object.
Good Continuation
Means Good Figure in German
Prägnanz
The perceptual field and objects within it will take on the simplest and most encompassing structure permitted by the given conditions.
Prägnanz or Principle of Simplicity
Similar things appear to be grouped together.
Similarity
Grouping may occur due to the similarity of size, shape, or orientation.
Similarity
___________ (1912) describes the principles as Intrinsic Laws which implies that the organizing principles are built into the system.
Wertheimer
Although a person’s experience can influence perception, the role of experience is minor compared to the perceptual principles.
Intrinsic Laws
Opposite to Helmholtz Likelihood principle which proposes that our knowledge of the environment enables us to determine what is most likely to have created the pattern on the retina.
Intrinsic Laws
Modern perceptual psychologists, agreeing with Helmholtz see our experience with the environment as a central component of perception.
Intrinsic Laws
Modern cognitive psychologists introduced the idea that perception is influenced by our knowledge of ____________________.
Regularities in the Environment
Characteristics of the environment that occur frequently.
Ex. Blue is associated with the open sky. Landscapes are often green and smooth, and buildings contain horizontal and vertical lines.
Regularities in the Environment
Two types of regularities:
Physical and Semantic
Regularly occurring physical properties of the environment.
Physical Regularities
People can perceive horizontals and verticals more easily than other orientations
OBLIQUE EFFECT
Human-made environments such as buildings contain lots of horizontals and verticals and also natural environments such as trees and plants are more likely to be vertical or horizontal than slanted
OBLIQUE EFFECT
Assumes that light is coming from above because the light in our environment including the sun, and most artificial light usually comes from above.
LIGHT FROM ABOUT ASSUMPTION
________ in perceptions refers to the meaning of a scene. (What happens within a scene?)
Semantics
Characteristics associated with the functions carried out in different types of scenes.
Semantic Regularities
Knowledge of what a given scene
typically contains.
SCENE SCHEMA
Ex. Visualizing a classroom would involve details within the scene. Most people would report seeing not just a single object but an object within a setting.
SCENE SCHEMA
Bayesian Inference was named after ________________
Thomas Bayes
Thomas Bayes proposed that our estimate of the probability of an outcome is determined by 2 factors:
- PRIOR PROBABILITY or Prior
- LIKELIHOOD of the outcome or likelihood.
It is our initial belief about the probability of an outcome
PRIOR
An extent to which the available evidence is consistent with the outcome.
LIKELIHOOD
It involves a mathematical procedure in which the prior probability is multiplied by the likelihood to determine the probability of the outcome.
Bayesian inference
People start with _____________ the use additional evidence to update this initial belief about the probability of a certain outcome and reach a conclusion.
prior probability
It is used by researchers to develop computer vision systems that can apply knowledge about the environment to more accurately translate the pattern of stimulation on their sensors into conclusions about the environment.
Bayesian inference
Comparison of the 4 approaches
________, ________, and ________ all have a common idea:
1. We use data bout the environment, gathered through our past experiences in perceiving, to determine what is out there.
- Top-down processing is an important part of these approaches.
Helmholtz, Regularities, and Bayes
Comparison of the 4 approaches
_________ emphasized the idea:
1. The principles of organization are built in.
- They acknowledged that perception is affected by experiences but argued that building principles can override experience thereby assigning bottom-up processing a more central role in perception.
Gestalt
Comparison of the 4 approaches
__________________ pointed out that the principles of organization in fact have been created by experience.
Modern cognitive psychologists
Experience shapes the way neurons respond.
Neurons and Knowledge About the Environment
Experiencing certain stimuli over and over again can shape the way neurons respond in perceptual systems.
Neurons and Knowledge About the Environment
The brain is changed or shaped by its exposure to the environment so it can perceive the environment more efficiently.
Experience-dependent plasticity
Using fMRI, they found out that the temporal lobe called the ______________ (FFA) contains many neurons that respond best to faces and can be measured by its level of activity as well as other complex objects.
fusiform face area
The brain’s functioning can be tuned to operate best within a specific environment. Regular exposure to stimuli can cause neurons to become adapted to respond best to these regularities.
Experience-dependent plasticity
___________ helps us perceive objects in the environment more accurately. Some aspects may not be apparent in a single viewpoint.
Movement
The visual signals that give us our experience of objects and events in the world are not the same ones that control our actions.
Movement Facilitates Perception
Even a simple action like picking a coffee cup
involves several areas of the brain that coordinate their activity to create perceptions and behavior.
Movement Facilitates Perception
Role of Culture in Perception
____________ cultures are more likely to engage in context-independent analytic perceptual processes.
Western
Role of Culture in Perception
___________ cultures are more inclined to employ context-dependent holistic perceptual processes. Asians are more interdependent and relationships are highly valued.
East Asian
TRUE or FALSE
Our perception is not fixed and universal.
TRUE
