PSYB57 Final: Visual Imagery
Mental imagery
The ability to create perceptual experiences without the physical stimuli.
There are more than 1 type of mental imagery:
Auditory imagery, olfactory imagery, tactile imagery.
Dual coding theory
Knowledge is represented by 2 sytems:
Verbal system: Images are represented by symbols (like words) that don't look anything like it, with the exception of onomatopoeia which are words that are pronounced like the image. (language, writing)
Analogue image-based code/ non-verbal system: information stored to represent the physical stimulus it is representing. (pictures, sounds)
Imagery debate
In what way is a image represented in the mind?
Descriptive or depictive?
Depictive representation
Images are stored as analogues that maintain their spatial and perceptual qualities.
You still know where everything is.
Has a lot of support.
Descriptive representations
Images are represented as symbols that convey abstract information but does not retain spatial or perceptive qualities.
Text information is taken out, creates a picture, and stored back in as text.
Relies entirely on propositions.
Images are byproducts of these symbols.
Difference between descriptive and depictive representations
Depictive retains spaital and perceptive information while descriptive does not.
Both say that propositions are used to represent memory.
But depictive says that images are just as important hwil descriptive says that it is just a byproduct.
Propositions
Statement that can be answered/confirmed with a yes/no, and describes relationships between objects.
Ex: apple is beside the stool.
3 ways to represent code
Depictive representations, verbal representations, propositional representations
If depictive representation is right
Spacing and timing should match up
Perception and imagery should use the same process.
Studies for spacing and timing matching up
Mental scanning: given a line photo and eyes fixate on one point and given another point to find and once you do, you press a button. Longer the distance between the 2 points, the more time it takes. Also has descriptive explanation where information is listed so they have to spend more time going through the list.
Mental rotation: given objects and asked if they were the same, but the objects are at different angles so they have to mentally rotate them. The ones at farther angles take slower to answer. avergae rotation is 60 degrees per second.
Mental scaling: object's descriptions are determined by their size and distance from the person. A cat is placed next to an elephant and asked to be described. It takes longer to describe than if placed next to a fly because you have to zoom in.
Studies for imaging relying on the same process as perception
When asked to imagine a lemon and shown a lemon below conciousness. When asked to describe the lemon, they describe it as the one they were unconciously exposed to. Perception getting mixed up with imagery.
Asked to imagine audio/image. Asked to tap on a button when detecting actual audio/visual stimuli. When they are imagiing, they miss it more/make more mistakes. It is taking up energy in the same process so there is insuffieceint resources for perception.
Motion aftereffects
Phenomenon when you are exposed to one motion for so long that afterwards, you will automatically see the other motion. Can happen with simple imagination instead of actually seeing the motion.
Study of doubt against depictive representation
Shown multiple shapes and asked if one was a part of another. If depictive, they should get it right because there is a perfect representation, but results were mixed. Some people did and others didn't.
Could be experimentar expectancy or demand characteristics.
Falsification
Doing a study to prove a claim/phenomenon wrong.
Imagery, perception and the brain
If they share the same process, perception should activate the same brain parts as imagery.
Brain damage and imagery
Damage to certain parts of the brain hinders both perception and imagery.
Patient TC damaged occipital and temporal lobe and got cortical blindness (perception) and can no longer anseerr questions about stimulis in his memories.
But this does not always happen.
A different patient managed the occipital lobe and bot cortical blindness but retained his imagery abilities.
The opposite may also be true.
Neuroimaging experiment
Person asked to memorixe a striped photo and asked questions about it. Activated the primary visual cortex, the same brain region as perception.
brain parts of imaging
Imaging activates specific parts of the brain based on the image.
Fusiform face area (FFA) for faces and Parahippocampal place area (PPA) for locations.
Brain activity different between perception amd imagery
Perception will have more/stronger brain activity because it is based off of actual stimuli with the activity of actual receptors.
Imagery just creates a neural simulation of that from a signal from the frontal lobe.
Multi-voxel pattern analysis
Technique for analyzing fRMI results that can predict cogntiive task someone is performing based on patterns of activity in the brain seen in the past.
Able to determine objects participants were imaging.
Generative adversarial network (GAN)
AI that can generate pictures.
Input are numbers while outputs are those pictures.
Diffusion models
AI that can generate images in a sense that they can denoise noisy photos with unknown pixels with a command sentence. They make a guess on what the pixel is and fill it in. Clarifies photos but can also generate new ones if the entire photo is just static.
Deepfakes
AI models of people of them doing stuff they have not done before.
Cognition that imagery effects
Memory, PTSD, anxiety, depression, mental wellness.
Not good to have too much or too little of imagery in mental illnesses.
picture superiority effect
Memory is made better when you imagine a picture of it.
Explaed with the dual coding theory because when you create an analogue code, you also give it an abstract verbal code of a label so you are recording it twice where as if there is no image, it is just one abstract verbal code.
Concreteness effect
Abstrack concepts are harder to memorize than non-abstract ones because you can make images of them better.
PTSD
Characterized with vivid flashbacks (imagery) to traumatic events. Can cause physical and emotional reactions like the ones to the real event. People with more imagery abilities are more suceptible. How worse it is is measured by the realness of flashbacks, not how often they show up.
Anxiety
Repeated and unwanted intrusive worries that hinders life. Imagery is of those worries. Makes them believe it will happen more if they keep seeing it.
Depression
Persistent feelings of sadness with loss of interest in other activities.
Too much imagery for sad thoughts. Suicide risk increased with more thoughts of it.
Too little imagery for happy thoughts.
Imagery re-scripting
A method to help mental illness by having patients imagine that they revised a regret/mistake in the past.
Types of learning and the effectiveness of each one
There is no difference in the effectiveness of different types of learning such as audio/visual learning. It is just that some people are exposed to certain types of stimuli more so they are better at it.
Congenital aphantasia
Inability/little ability to form visual images.
3-5% of population.
Good for lexx creative more serious professions like mathemetician,
Hyper aphantasia
Too much ability to form visual images.
Good for creative professions.
Differences in visual imagery and whether that affects other functions?
Unrelated to other abilities like working memory and intelligence.
If depictive representations
People should process images and physical stimuli similarily.
If descriptive represntations
mental processing would depend on propositions, not perceptual and spatial characteristics of stimuli