Visual Imagery Flashcards
What is Mental Imagery?
Our ability to create a sensory experience in the absence of an actual stimulus
What does Mental Imagery tie together? How do humans use it?
It ties together all we’ve been talking about! Memory, Attention, etc… People use it to generate images
What is the means behind making a picture/movie in your head? (that you may or may not have experienced before)
Visual Imagery
What can you use as a sort of memory?
Visual Imagery
What does Mental imagery engage to construct the experience?
Perception, Attention, Object Perception, short and long term memory
Is Mental Imagery like Episodic Retrieval? Why?
No! It’s an active composition of what you want to include (in control of what percepts are being experienced)–Attention!
Can Mental Images be something you’ve never experienced before?
Yes!
Do people all have the same level of Mental Imagery ability? Likely explanation?
No! Some are great, others are not so much–The same information in the world can be represented in different ways
Is there neural activity in Mental/Visual Imagery? Why?
Yes! You are causing it to happen to create this thing in your head that you’re causing to happen
Define a Propositional Representation–Example?
Representation using abstract symbols or factual knowledge–Just knowing that your stapler is in your desk drawer
What kind of memory is Propositional Representation
Semantic Memory
Which Imagery Representation is language-based?
Propositional Representation
Define a Depictive Representation–Example?
Representing information as a picture that can be scanned (imagining your desk then looking for a stapler)
How do you know that German Shepherds have upright ears?
Depictive Representation! Mental Imagery
Do animals have Mental Imagery?
No! It’s a higher-level function
What kind of Representation for Mental Imagery depends on…
…what we are trying to do
What kind of Visual Representation do maps use? Why?
Depictive Representation–to reason out spatial relationships
What did Shepard & Metzler (1971) do in their Visual Imagery experiment?
They showed subjects pairs of block objects and asked them if they were the same or different–changing their rotation
What was the prediction of the Shepard & Metzler (1971) Visual Imagery experiment?
If the objects were represented using a depictive code, then larger angular separations should make longer Reaction Times (RTs)
What would did Shepard & Metzler (1971) predict would happen if subjects used a Propositional Representation in their Visual Imagery experiment?
It would have no effect on the angular separation RT
What was the result of the Shepard & Metzler (1971) Visual Imagery experiment?
RTs increased with the angular separation between the objects (subjects needed longer to determine the objects were the same at higher degrees rotated)
What was the conclusion of the Shepard & Metzler (1971) Visual Imagery experiment?
Subjects were solving this task by mentally rotating one object until it matched the other–and the speed of mental rotation is about 40 degrees per second
What method did Kosslyn (1973) use to study Mental Imagery?
He had subjects study a picture, then form a mental image of it and “look” at a particular part–subjects then answered a question about another object either Near or Far from their starting point
What was Kossyln (1973)’s prediction for his experiment?
If imagery is spatial, like perception, then RTs should be longer to questions about far things due to subjects having to scan over a greater distance
Is perception spatial?
Yes!
What was the result of Kosslyn’s (1973) experiment?
Subjects took longer to respond to far objects than to near objects
What was the conclusion of Kosslyn’s (1973) study?
A Mental Image is spatial (picturial); we “scan” a mental image just like we would scan an actual picture
Does it take equal time to move our inner “eyes” as our physical ones?
No! Inner “eyes” take longer
Who found out that a Mental Image is Spatial?
Kosslyn
Did Kosslyn’s results match his prediction?
Yes!
What does Pylyshyn argue against in (1973)?–First arguement
Kossyln’s conclusion that people use depictive/mental scanning
What does Pylyshyn (1973) argue that Kossyln’s results can be explained by?
A Propositional Code
What is a Propositional Code?
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Why does Pylyshyn argue that Kossyln’s results can be explained by a Propositional Code?
Assuming that time is needed to travel along each link in a knowledge structure, it should take longer to reach one end than your starting point
What method do Kossyln, Ball, and Reiser (1978) use to study Mental Imagery?
Subjects studied the locations of landmarks on a map, and then created a mental image–they were then told to start at one location and to imagine a dot moving to another location and to press a button when they reached it
What was the variable in the Kossyln, Ball, and Reiser (1978) study?
Each pair of objects had a different distance, and every object pair was tested
What was the results of the Kossyln, Ball, and Reiser (1978) study?
The time needed to scan between two objects in the image increased linearly with the distance between those objects (Subjects needed less time to move their mental eye when the distance was short compared to when it was long)
What was the conclusion of the Kossyln, Ball, and Reiser (1978) study?
Subjects form a depictive representation and mentally scan it like they would to an actual picture
What did Pylyshyn argue against in 2003?–Second arguement
The Kossyln, Ball, and Reiser (1978) study that used a map to prove Depictive Representations
What did Pylyshyn argue in 2003 – second
Subjects may be using their Tacit Knowledge to implicitly guide their behavior during a mental imagery task–because subjects know it should take longer they make their behavior conform to this relationship unconsciously
What is the Tacit Knowledge in Pylyshyn’s 2003 argument?
Subject’s knowledge of how physical systems work
What method did Finke and Pinker (1982) use to study Mental Imagery?
Subjects would see a display of dots, followed by an arrow, their task was to indicate whether the arrow point to one of the dots
What was a large difference in the Finke and Pinker (1982) study compared to the Kossyln, Ball, and Reiser (1978) study?–What else?
There was no explicit mention to mentally scan or of it being an imagery experiment
What was the results of the Finke and Pinker (1982) study on Mental Imagery?
The time that subjects took to make their judgement increased with the distance between the arrow tip and a dot in the previous display
What was the conclusion on the Finke and Pinker (1982) experiment?
Subjects formed a mental image of the dot display and then scanned from the arrow to see if it hit a dot
What argues against Tactic Knowledge? Why?
Finke and Pinker’s 1982 study–subjects had no reason to believe that distance was relevant to the task
What method did the LeBihan et al. (1993) study on Mental Imagery use?
Subjects were either shown an object or asked to imagine the object–fMRI was used to measure brain activation in the visual cortex under each condition
What was the fMRI used for in the LeBihan et al. (1993) study?
It measured brain activation in the visual cortex under each condition
What was the results of the LeBihan et al. (1993) study?
Visual Cortex activates when seeing or just imagining an object
What was the conclusion for the LeBihan et al. (1993) study? What does this argue against?
Imagery activated the same brain areas used in perception; not what should be expected from a Propositional Code
When did the fMRI signal get increased information in the LeBihan et al. (1993) study?
When stimulus was applied and when the subject imagined it
When did the fMRI signal get decreased information in the LeBihan et al. (1993) study?
When the subject didn’t see the stimulus and when they didn’t imagine it
What method did the Bisiach and Luzzatti (1978) study of Mental Imagery use?
They had subjects with Visual Neglect imagine standing at a certain location in a famous piazza, and to describe what they “saw”
What is Visual Neglect?
Visual information from the left visual field is ignored because of injury to their right parietal cortex
What was the results of the Bisiach and Luzzatti (1978) study?
Subjects only described the buildings that would have appeared in their right visual field
What was the second method that Bisiach and Luzzatti (1978) employ?
They then asked subjects to imagine viewing the piazza from the opposite direction
What were the results from the second method in the Bisiach and Luzzatti (1978) study?
Subjects now described the buildings that they had previously ignored
What did the Bisiach and Luzzatti (1978) study show?
People don’t imagine things how they might have remembered them, but rather how they might have seen them
What are the implications of Mental Imagery for Memory?
Dual Code Theory and Reality Monitoring
What is the Dual Code Theory (Paivio, 1963)?
Some words in a memory experiment can just be coded propositionally, others can be coded using both propositional and pictorial codes
What is a Propositional Code in Dual Code Theory? Examples?
Abstract Nouns; “idea” “justice”, things that you don’t have a ready image for
What is a Pictorial Code in Dual Code Theory? Examples?
Concrete nouns like “dog” or “George Washington”; ones that you have a ready image for
What is the concept of Reality Monitoring (Johnson et al. 1979)? What is it a technique for?
We may occasionally confuse something that we only imagined for something that we actually experienced. Reality Monitoring is a technique for dissociating memories for real events from memories of imagined events
What was Johnson et al (1979) study’s methods?
Subjects were subjected to pictures and words mixed together and told to remember the items and so make an image for the words they see and at the end given a test to see how many images they think they saw
What were Johnson et al. (1979)’s two groups?
“Good imagers” and “Bad imagers”
What was the prediction for the Johnson et al. (1979) study?
Good imagers would find it harder to give an accurate estimate of pictures because they would get confused as to whether they had seen or imagined something
What were the results of the Johnson et al. (1979) study?
Good imagers were more likely to overestimate how often they had seen pictures compared to poor imagers
