Chapter 8: Visual Imagery & Spatial Cognition Flashcards
Mnemonics
Various techniques used to increase chances of remembering
Many but not all use imagery
Mnemonic Methods
Method of loci
Interacting images
Pegwords
Ordered cues
Etc.
Method of Loci
Requires learner to imagine a series of places (locations) that have some sort of order
Imagine the items you have to remember in those locations
Using visualization to recall what is needed (walk the same path over again in your mind)
Can recall up to 38 of 40 words after one presentation
Principles Improving Method of Loci
Cues must be memory images of geographic locations
Use interactive images to link the item and its cue location
If you study the items more than once, the same cue location should be used for a given memory item
Interacting Images
Recall of concrete nouns on a list improved when participants were told to form images of the words
For images to be maximally effective in paired associates, participants should try to form images that interact (e.g. a goat smoking a pipe, no two separating)
Bizarreness has no effect on recall
Pegword method
Picturing items with another set of ordered cues, pegging them to the cue
Cues are not locations but are nouns that come from a memorized rhyming list
Participant needs to picture the first item interacting with a bun, second with a shoe, third with a tree
10 or less items
Memory techniques Not Including Visual Imagery
Recoding material to be recalled
Adding extra words or sentences to mediate or go between memory and material
E.G. every good boy deserves fudge
Categorization and organization of material also improve recall
Dual Coding Hypothesis
Long term memory contains two distinct coding systems for representing info to be stored
Verbal: containing info about an item’s abstract, linguistic meaning
Imagery: mental pictures of some sort that represent what the item looks like
Relational-Organizational Hypothesis
Imagery improves memory because imagery produces more associations between the items to be recalled
Forming an image requires a link between the info to be remembered and other information
Example of Dual Coding
Participants learning one of four lists of noun pairs
Either two concrete nouns, two abstract nouns or one of each
Recall was worse for abstract firs pairs
Because can’t use visual labelling for abstract words, more concrete words can have rich imagery
First noun in pair serves as a conceptual peg for the second word
Relational-Organizational Example
Participants told to use overt rote repetition, construct two images that did not interact, or construct an interactive scene of two words in pair
Rote memorization: 30% of paired associates
Noninteractive imagery: 27% of paired associates recalled
Interacting images: 53% of paired associated recalled
Proves that it is not imagery itself but how imagery is used that helps memory
Empirical Evidence For Imagery
Participants were faster at identifying whether a corner was at the top of the letter F when they used verbalization as their response method
Requires formation of visual image of an F
Visual image probably has some picture like qualities, so a visually guided response (pointing) would be more disruptive of the spatial visual task
People were faster to respond by pointing when asked to identify if words in a sentence were nouns
Pointed to yes or no
Holding a sentence in memory would be more disrupted by verbal responses than by a spatial task
Mental Rotation of Images
Amount of time it takes participants to determine if two drawings are depicting the same object or a mirror image reversal is proportional to the angle of rotation between the drawings
Suggests that they performed the task by mental rotation of 3D images
The time to compare is related to the degree of rotation
When presenting participants with irregular polygons, they still rotate the whole polygon (not just parts) because their performance was the same across all types of shapes
Scanning Images
Participants formed a visual image and then scan it, moving from one location to another in their image
Imaginal Scanning
Moving a visual image from one location to another within their image
The time it takes people to scan reveals something about the ways images represent spatial properties such as location and distance
Evidence For Scanning
Participants studied an imaginary island with different landmarks
The length of time taken to scan between landmarks correlated with the actual distance between objects on the map
Demonstrates that people’s scanning is similar to scanning of real pictures
Participants study drawings of objects that are elongated in one direction and have easily describable ends and middle
The loner the distance from the designated end to the location of the part, the longer it took people to say whether the part they looked for was in the drawing
Presumably because visual image formed preserves spatial characteristics of the drawings
Principles of Visual Imagery
Implicit encoding
Perceptual equivalence
Spatial equivalence
Transformational equivalence
Structural equivalence
Implicit Encoding
Implicit encoding: info stored unintentionally along with other info
Mental imagery is instrumental in retrieving info about physical properties of objects or physical relationships among objects that was not explicitly encoded at a previous time
E.g. construct a visual image of your kitchen to count the number of cabinets
Perceptual Equivalence
Imagery is functionally equivalent to perception - similar mechanisms in the visual system are activated when objects or events are imagined
Imagery can prime visual pathway (e.g. participants told to imagine a certain level perceived a faint projection of it quicker)
Spatial Equivalence
Spatial arrangement of elements of mental image correspond to the way objects or their parts are arranged on actual physical surfaces or space
Evidence comes from scanning studies
Transformational Equivalence
Imagined transformations and physical transformations exhibit corresponding dynamic characteristics and are governed by same laws of motion
Evidence comes from studies of mental rotation
Structural Equivalence
Structure of mental images corresponds to that of perceived objects, structure is coherent, well organized, and can be reorganized and reinterpreted
Visual images are formed in pieces, then assembled into a final rendition
Participants took longer to form detailed mental pictures
Critiques of Mental Imagery Research
Tacit knowledge/demand characteristics
Picture metaphor/analog position
Propositional theory
Mental Imagery: Tacit Knowledge/Demand Characteristics
Experiments themselves give enough hints (explicit or implicit) for people to perform by relying on beliefs and knowledge and not on visual imagery alone
E.g. People may be mentally pausing in image scanning experiments because of beliefs/expectations about what experimenters want
Experimenter expectancy effects influence many investigations
Mental Imagery: Picture Metaphor/Analog Position
Pictures and images are different
You can physically look at a picture without first knowing what its a picture of, but can’t do the opposite
Pictures and images are disrupted in different ways
Images are more easily distorted by viewer’s interpretations (e.g. false memories)
Mental Imagery: Propositional Theory
Reject the idea that images serve as a distinct mental code for representing info
Believe there is a single code that is propositional in nature used to store and mentally represent info
Propositions can be linked in networks
When people don’t use imagery, quicker to identify that cats have claws (high association value, small visual part)
Spatial Cognition
How people represent and navigate in and through space
E.g. a cognitive map (mental depiction of some part of our environment)
Space of the Body
Includes knowledge of where the different parts of one’s body are located at any moment
Space Around the Body
Area immediately around you
Space of Navigation
Larger spaces (e.g. ones we walk through, explore, and travel through)
E.g. when giving directions to someone
Locomotion: moving the body over terrain
Wayfinding: planning and making decisions about where to go and how to get there
Neuropsychological Findings: Cerebral Blood Flow
Occipital lobe and other posterior regions highly active during imagery tasks
Amount of activation increased if participants were told to visualize large versions of one image
Parahippocampal place area (ventromedial area): forming images of a place
Fusiform face area: when formed images of faces
Neuropsychological Findings: Vegetative State
Can’t physical respond to commands, but shows evidence that some individuals can respond to commands internally
Tell people to imagine walking through house (activates parahippocampal gyrus and parietal lobe) vs playing a sport (supplementary motor area)
Attach these visualizations to a response of yes or no (e.g. imagine walking through your house if answer is yes)
Neuropsychological Findings: Occipital Lobe Removal
MGS had her right occipital lobe removed as treatment for epilepsy
Removing part of the visual cortex decreases field of view
Before and after surgery, MGS performed a mental walk task
Imagined walking toward an animal and estimate how close she was when the image began to overflow her visual field
Proved her visual field became smaller in imagination too
Neuropsychological Findings: Single Cell Recordings
Electrodes implanted in the medial temporal lobe of a patient with severe epileptic seizures
Found category specific neurons: neurons that respond to some objects but not others
Neuropsychological Findings: Quadrant Experiment
Subjects memorized a display containing four quadrants
The subjects were scanned as they closed their eyes and visualized the display,
Heard two numbers, which had previously learned labels for specific quadrants, followed by the name of a dimension (such as length)
They were to decide whether the set of stripes in the first names quadrant was greater along that dimension than the set of stripes in the second named quadrant
Activation in primary occipital cortex during task (V1)
