Chapter 10: Visual Imagery Flashcards
Visual Imagery
Seeing in the absence of a visual stimulus
Mental Imagery
- Broader than visual imagery
- The ability to recreate the sensory world in the absence of physical stimuli
- Refers to all senses
History of Imagery in Psychology: Imageless Thought Debate
- Some psychologists said thoughts were impossible without images
- Others said thinking can occur w/o images
History of Imagery in Psychology: Paired-Associate Learning Experiments
- p’s are presented with pairs of words initially, later asked to recall the second word after hearing the first word
- used in mental imagery experiments to show that concrete nouns are easier to remember than abstract ones due to better visualization
History of Imagery in Psychology: Paivio’s Conceptual Peg Hypothesis
- Concrete nouns create images that other words can ‘hang onto’ and are therefore easier to remember
History of Imagery in Psychology: Shepard & Metzler’s Mental Chronometry
- Determined the amount of time needed for various cognitive tasks
- P’s were said to be ‘mentally rotating’ objects in order to verify if they were the same shape
- Mental rotation = mental imagery
The Mechanisms of Imagery vs Perception
While imagery is not as vivid or lasting as perception, they share many similarities
The Mechanisms of Imagery vs Perception: Kosslyn’s Mental Scanning
- P’s create mental images and then scan them in their minds
- Increased time to find objects farther away from the middle was evidence for mental scanning
The Mechanisms of Imagery vs Perception: The Imagery Debate
Is imagery based on spatial mechanisms (like perception) or propositional mechanisms (like language - conceptual)
The imagery Debate: Kosslyn’s Spatial Representations
- Representations in which different parts of an image can be described as corresponding to specific locations in space
The Mechanisms of Imagery vs Perception: Pylyshyn’s Spatial Experience as Epiphenomenon
Pylyshyn argued against Kosslyn, claiming that just because we experience imagery as spatial doesn’t mean it uses the same underlying mechanisms as perception
The Mechanisms of Imagery vs Perception: Pylyshyn’s Propositional Representations
- Representations in which relationships can be represented by abstract symbols
- Can be thought of like a math equation (2 + 2 are abstract concepts) which can also be represented spatially (2 beers + 2 beers = 4 beers)
The Mechanisms of Imagery vs Perception: Depictive Representations
Non-abstract representations of actual things
- i.e., a picture of a cat underneath a table
Comparing Imagery & Perception: Mental Walk Task
- P’s were asked to imagine themselves walking toward a mental image of an animal and say how close they were before the image filled their ‘visual field’
- Results showed that mental imagery was similar to perceptual imagery
Imagery & The Brain: Imagery Neurons
- Brain measuring found evidence for neurons that fired both when p’s saw a pic of a baseball and when they were asked to picture a baseball
- Evidence for imagery & perception sharing the same mechanisms
Imagery & The Brain: A Topographic Map
- Showed that looking at smaller shit activated neurons farther back in the occip lobe and bigger shit activated them further forward
- When asked to imagine small and big shit, the same pattern was seen
- More evidence for shared fuckin mechanisms between imagery & perception
Imagery & The Brain: Multivoxel Pattern Analysis (MVPA)
- A CPU programmed to detect patterns of brain behaviour was able to guess (above chance) what a person was imagining based on brain patterns from when they were actually perceiving shit
- More evidence for shared mechanisms between imagery & perception
Imagery & The Brain: Patient M.G.S & Removing the Visual Cortex
- Removing part of her visual cortex in turn made her mental-visual field smaller
- More evidence for shared mechanisms!
Imagery & The Brain: Unilateral Neglect
- Damage to the parietal lobes can cause patient’s to not be able to see shit in one half of the visual field
- This has been shown also in mental images, implying that mental imagery & perception share mechanisms again
Imagery & The Brain: Dissociation Between Imagery & Perception
- There have been cases of people with brain damage that caused impaired imagery but not perception & vice versa
- Evidence for different mechanisms this time!!
Imagery & Memory: The Method of Loci
- A method of remembering where one imagines a spatial layout that’s familiar and then places things to remember within that layout
Imagery & Memory: The Pegword Technique
- Make a list of rhyming words with numbers
- Associate these rhyming words with items in a list that need to be remembered
Individual Differences in Visual Imagery: Spatial Imagery vs. Object Imagery
- Spatial Imagery: The ability to imagine spatial relations (i.e., the layout of a garden)
- Obect imagery: The ability to imagine visual details, features, or objects (i.e., a rose bush with bright red roses)
Individual Differences in Visual Imagery: The Paper Folding Test (PFT)
- Designed to measure spatial imagery
- P’s see a piece of paper folded and then hole-punched
- Have to choose from a group what it will look like after it’s unfolded
Spatial vs Object Imagers: The Vividness of Visual Imagery Questionnaire (VVIQ)
- Designed to measure object imagery
- Rated out of 5 the vividness of a mental picture they were asked to create
Spatial vs Object Imagers: The PFT vs The VVIQ
- Tests were shown to be negatively correlated! (Low PFT = High VVIQ & vice versa)
Spatial vs Object Imagers: The Degraded Pictures Task vs. The Mental Rotation Task
- Degraded Picture Task: a line drawing is presented hidden between a bunch of little marks & lines (object imagers did better)
- Mental Rotation Task: Asked p’s to judge if an object was the same or different than a rotated one (spatial imagers did better)
