CHAPTER 3: Perception Flashcards
Definition of perception:
conscious experiences resulting from stimulation of the senses.
Why is meant by the stimulus on the receptors ambiguous?
inverse projection problem: light from an object is inverted as it falls on the retina. The same pattern of light could be caused by an infinite number of different objects, yet our brains usually manage to make the correct interpretation
Why is it do difficult for the computer to perceive objects as we do?
1) Stimulus on the receptors are ambiguous
2) objects can be hidden or blurred
3) objects look different from different viewpoints
Definition of viewpoint invariance?
the ability to recognise an object seen from different viewpoints
What is bottom-up processing?
Bottom-up processing begins with the retrieval of sensory information from our external environment to build perceptions based on the current input of sensory information.
Looking at something creates an image on the retina
this image generates electrical signals that are transmitter through the retina, and then to the visual receiving area of the brain. This is when environmental energy stimulates the receptors.
What is top-down processing?
Top-down processing is the interpretation of incoming information based on prior knowledge, experiences, and expectations.
Processing that originates in the brain, at the “top” of the perceptual system
Knowledge we have of the environment, expectations we bring to the perceptual situations that enables us to rapidly identify objects and scenes
______ refers to what comes from the environment and _____ refers to what the individual brings
bottom-up; top-down
What is the study “the multiple personalities of a blob” - Olivia and Torralba (2007)?
A blob is identical in every scene, but is perceived as a different object depending on orientation and context within which they are seen.
This happens because of our knowledge of the kinds of objects that are likely to be found in different types of scenes
What is speech segmentation?
the ability to tell when one word in a conversation ands and the next one begins.
If a listener does not understand a language, the continuous sound signal enters the ears and triggers signals that are sent toward the speech areas of the brain.
Is this an example of bottom-up or top-down processing?
Bottom-up processing
If a listener understands a language, their knowledge of the language creates the perception of individual words?
Is this and example of bottom-up or top-down processing?
Top-down processing
When was the direct pathway model proposed?
1950s-1960s
What does the direct pathway model propose?
pain occurs when receptors in skin (nociceptors) are stimulated and send signals in a direct pathway from skin to brain
What are the four conceptions of object perception?
- Helmholtz’s unconscious inference
- The Gestalt laws of organisation
- Regularities in the environment
- Bayesian inference
What is Helmholtz’s Theory of Unconscious inference?
One of Helmholtz’s contribution to perception was based on his realisation that the image on the retina is ambiguous. He also proposed the likelihood principle and that is most likely occurs by a process called unconscious inference.
What is Likelihood principle?
We perceive the object that is most likely to have caused the pattern of stimulus we have received
What is unconscious inference?
A process in which out perceptions are the result of unconscious assumptions, or inferences, that we make about the environment
What is the gestalt principles of organisation?
Goal of the gestalt approach was the same as Helmholtz’s –to explain how we perceive objects- but they approached the problem in a different way.
The Gestalt Psychologists rejected Wundt’s idea of?
The Gestalt Psychologists rejected Wundt’s idea (structuralism) that perceptions were formed by ”adding up” sensations.
Old vs New Structuralism:
• “Old”view–structuralism
– Perception involves adding up sensations
• “New” view–Gestalt psychologists
– The mind groups patterns according to laws of perceptual organization
Principles of Perceptual Organization:
• Explain the way elements are grouped together to create larger objects
Example: some black and white shapes that become perceptually organized into a Dalmatian
The principle of good continuation:
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.
• Also, objects that are overlapped by other objects are perceived as continuing behind the overlapping object.
Law of Pragnanz is also known as?
principle of good figure or the principle of simplicity
Law of Pragnanz:
every stimulus pattern is seen in such a way that the resulting structure is as simple as possible.
Principle of Similarity:
Similar things appear to be grouped together.
There are many other principles of organization but the main message is that the Gestalt Psychologists realized that perception is determined by….
specific organizing principles
Summary of Gestalt:
– Perception is determined by specific organizing principles, not just dark and light stimuli activating the retina.
– Role of experience is minor compared to these intrinsic, “built in” principles.
– Experience can influence perception but is not the key driver.
Regularities in the Environment:
frequently occurring characteristics.
What are the two types of Regularities in the Environment:
1) Physical regularities
2) Semantic regularities.
Physical Regularities:
Regularly occurring physical properties of the environment
• Example: there are more vertical and horizontal orientations in the environment than oblique (angled) orientations (in human-made and also natural environments).
Oblique effect:
We perceive verticals and horizontals more easily than other orientations.
What is light-from-above- assumption.?
– Light comes from above
– Is usually the case in the environment
– We perceive shadows as specific information about depth and distance
Semantic Regularities:
The characteristics associated with the functions carried out in different types of scenes.
• For example: food preparation, cooking and perhaps eating occur in a kitchen.
Scene schema:
Knowledge of what a given scene typically contains.
Bayesian inference:
…is a mathematical procedure for determining what is likely to be “out there”; it takes into account a person’s prior beliefs about a perceptual outcome and the likelihood of that outcome based on additional evidence.
– In Bayesian inference prior knowledge plays an important role in identifying the likelihood of an event.
What did Thomas Bayes propose?
proposed that our estimate of the probability of an outcome is determined by 2 factors
What are the two facts that Thomas Bayes proses that our estimate of the probability of an outcome is determined by?
- The Prior Probability: our initial belief about the probability of an outcome
- The likelihood of the Outcome: the extent to which the available evidence is consistent with the outcome.
When looking at the four conceptions of Object Perception, which fall under bottom-up and top-down processing?
Top-down processing:
– (1) Unconscious inference
– (2) Environmental regularities
– (3) Bayesian inference
Bottom-up processing:
– (4) Gestalt principles
What did Radel & Clement-Guillotin (2012) investigate?
they investigated whether being hungry or not affects how quickly and how accurately food-related words are seen
What did Radel & Clement-Guillotin (2012) study’s results suggest?
that motivation must have played a role in very early perception, namely by modulating which stimuli get access to conscious awareness. It means that somehow our brain can make a distinction (and act upon it) between a neutral and food related word before we become conscious of them.
Experience can shape the way neurons respond. TRUE or FALSE?
TRUE
Why is it that experience can shape the way neurons respond?
There are more neurons in the animal and human visual cortex that respond to horizontal and vertical orientations than to oblique (slanted) orientations
Some neurons respond best to things that occur regularly in the environment
Why are there more neurons that respond to horizontals and verticals?
- Theory of natural selection
- Experience-dependent plasticity
What is the theory of natural selection?
Characteristics that enhance an animal’s ability to survive, and therefore reproduce, will be passed on to future generations
What is the process called experience-dependent plasticity?
mechanism through which the structure of the brain is changed by experience
Learning can shape the response properties of neurons
Rearing cats in horizontal or vertical environments can cause neurons in the cat’s cortex to fire preferentially to horizontal or vertical stimuli is an example of what?
experience-dependent plasticity
Greeble stimuli used by Gauthier. Participants were trained to name each different Greeble. What did the results conclude?
Support the idea that neurons in the FFA respond strongly to faces not just because this was organized this way long before birth, but also because we have a lifetime of experience perceiving faces.
- It shows that the brain’s functioning can be “tuned” to operate best within a specific environment.
- Continued exposure to things that occur regularly in the environment can cause neurons to become adapted to respond best to these regularities.
According to your textbook, perception goes beyond the simple receipt of sensory
information. It is involved in many different cognitive skills. Which of the following is NOT one of those skills as noted by the chapter?
A : Solving problems
B : Experiencing neuromodulation
C : Communicating with other people
D : Answering questions
B : Experiencing neuromodulation
Perception is NOT essential for A : creating memories. B : acquiring knowledge. C : solving problems. D : improving empathy
D : improving empathy
The task of determining the object responsible for a particular image on ones retina is called the
A : radiated wavelength paradox.
B : inverse projection problem.
C : serial location task.
D : fusiform face role
B : inverse projection problem.
Members of a security team are stationed on rooftops surrounding a large city plaza before a scheduled rally. Suddenly, three team members in different locations radio in to the command center, each stating that they have spotted a suspicious box on the ground with a pipe coming from the top. What enables the security team members to report seeing the same object despite being stationed on different rooftops?
A : Semantic regularity
B : Viewpoint invariance
C : Bottom-up processing
D : Principle of similarity
B : Viewpoint invariance
Viewpoint \_\_\_\_\_\_\_\_ is the ability to recognize the same object even if it is seen from different perspectives. A : consistency B : resistance C : constancy D : invariance
D : invariance
The sequence of steps that includes the image on the retina, changing the image into
electrical signals, and neural processing is an example of _____ processing.
A : bottom-up
B : top-down
C : Gestalt
D : serial
A : bottom-up
If a word is identified more easily when it is in a sentence than when it is presented alone,
this would be an example of _____ processing.
A : top-down
B : bottom-up
C : serial
D : sequential
A : top-down
Maria took a drink from a container marked milk. Surprised, she quickly spit out the liquid because it turned out that the container was filled with orange juice instead. Maria likes orange juice, so why did she have such a negative reaction to it? Her response was most affected by
A : reception of the stimulus.
B : bottom-up processing.
C : top-down processing.
D : focused attention.
C : top-down processing.
Perceiving machines are used by the U.S. Postal Service to read the addresses on letters
and sort them quickly to their correct destinations. Sometimes, these machines cannot read an address because the writing on the envelope is not sufficiently clear for the machine to match
the writing to an example it has stored in memory. Human postal workers are much more
successful at reading unclear addresses, most likely because of
A : bottom-up processing.
B : top-down processing.
C : their in-depth understanding of principles of perception.
D : repeated practice at the task.
B : top-down processing.
Which of the following is an example of an effect of top-down processing?
A : Recognizing a crying friends sounds as words in a sentence
B : Seeing a flash of lightning in a thunderstorm
C : Walking all around a car and always knowing its a car
D : Perceiving all of the birds in a flock as belonging together
A : Recognizing a crying friends sounds as words in a sentence
Speech segmentation is defined as
A : creating a sentence from a series of spoken words.
B : ignoring the spaces between the spoken words of a sentence.
C : organizing the sounds of speech into individual words.
D : recognizing a few words out of many when hearing a largely unfamiliar language
C : organizing the sounds of speech into individual words.
When Carlos moved to the United States, he did not understand any English. Phrases like Anna Mary Can Pi and I Scream Class Hick didnt make any sense to him. Now that Carlos has been learning English, he recognizes this phrase as An American Pie and Ice Cream Classic. This example illustrates that Carlos was not capable of ____ in English.
A : speech segmentation
B : the likelihood principle
C : bottom-up processing
D : algorithms
A : speech segmentation
Evidence for the role of top-down processing in perception is shown by which of the following examples?
A : When someone can easily select a target that has a feature distinct from distracters
B : When someone cannot read an illegible word in a written sentence
C : When someone easily identifies an object even though that object is unexpected in that
context (e.g., identifying a telephone inside a refrigerator)
D : When someone accurately identifies a word in a song on a radio broadcast despite static interfering with reception
D : When someone accurately identifies a word in a song on a radio broadcast despite static
interfering with reception
Which of the following is true about perception?
A : It occurs separately from action. B : It is mostly automatic. C : It involves rapid processes. D : It is the result of many cognitions such as creating memories, acquiring knowledge, and solving problems.
C : It involves rapid processes.
The theory of unconscious inference includes the
A : oblique effect.
B : likelihood principle.
C : principle of componential recovery.
D : principle of speech segmen
B : likelihood principle.
The likelihood principle states that
A : we perceive the object that is most likely to have caused the pattern of stimuli we have
received.
B : we perceive size to remain the same size even when objects move to different distances.
C : it is easier to perceive vertical and horizontal orientations.
D : feature detectors are likely to create a clear perception of an object.
A : we perceive the object that is most likely to have caused the pattern of stimuli we have
received.
The process by which small objects become perceptually grouped to form larger objects is the principle of perceptual
A : conjunction.
B : organization.
C : discriminability.
D : fusion
B : organization.
You look at a rope coiled on a beach and are able to perceive it as a single strand because
of the law of
A : good continuation.
B : simplicity.
C : familiarity.
D : good figure.
A : good continuation.
You are at a parade where there are a number of marching bands. You perceive the bands
that are all in the same uniforms as being grouped together. The red uniforms are one band, the
green uniforms another, and so forth. You have this perceptual experience because of the law
of
A : simplicity.
B : similarity.
C : pragnanz.
D : familiarity.
B : similarity.
The notion that every stimulus pattern is seen in such a way that the resulting structure is
as simple as possible is called the law of
A : common fate.
B : similarity.
C : pragnanz/good figure
D : continuity
C : pragnanz/good figure
Entering a church service and seeing someone selling hot dogs and cotton candy from a
cart near the altar would be perceived as a violation of
A : mirror neurons.
B : natural selection.
C : scene schema.
D : pragnanz.
C : scene schema.
