Chapter 4: mental imagery Flashcards
what is the central theme of this chapter
To what degree are the processes behind visual imagery (imagining something) the same as perceptual and attentional processes (seeing something)?
how are seeing something and imagining something the same and different
In some ways, they’re the same: Roland and Friberg’s (1985) Study of Brain Activation Patterns During Mental Imagery vs. Verbal Imagery: rehearse jingle or spatial route
-When people imagined going through a spatial route or rehearsing a jingle, the same parts of the brain were used (frontal lobe, parietal lobe and frontal lobe)
In some ways they’re different
-Picture a tiger…
-…how many stripes does it have?
explain the movie scene study
-Nishimoto et al. (2011) reconstructed movies from the brain activity of participants watching these movies.
-Tried to reconstruct scenes from the movies based on brain scenes (the photos on the slide show what the scenes looked like), the images were strikingly similar
what is mental imagery
Processing of perceptual-like information in the absence of an external source for the perceptual information
explain the study of verbal imagery vs visual imagery (letters and shapes in boxes)
-Geometric condition
-Verbal condition
-Saw geometric shapes or words, then would show boxes to you and you would have to determine if whatever is in the box is what you saw in real life
-Interested in how quickly people were able to make the determination, they found that when people did it for shapes they did it most quickly when the shapes were arranged in the same way they were arranged in the original box, this was not true for the words, there was no difference in how the words were laid out
-Shows that verbal configuration might be different than geometric configuration in the brain
-Interaction was found
what is mental rotation
the process of continuously transforming the orientation of a mental image
explain the shepard and metzler study with rotating shapes
-Among the first to study the functional properties of mental images
-Mental process analogous to physical action
-In a study where people were asked to mentally rotate shapes, they found that the greater degree of angular disparity the greater it takes people to determine if they are the same shape or not
-This is interesting because it shows that mental rotation and actual rotation work in the same way
Results of the study
-The greater the angle of disparity between the two objects, the longer the participants took to complete the rotation.
-Linear relationship
-True for picture plane and 3-D rotations
-The mental process appears to be analogous to the physical rotation.
explain the image scanning study with the letter F
SCANNING MENTAL IMAGES (Brooks, 1968)
-Mentally scanned a mental array of a block diagram of the letter F (visual) or a sentence (non-visual)
-Respond to turns or nouns
-Picture a sentence and when you come across each word you have to say if a word is a noun or not
Responses could be made
-Verbally
-By tapping
-On this output sheet. (see on powerpoint)
The letters are staggered to force careful visual monitoring of pointing.
Results
-Greatest difficulty when doing two spatial tasks simultaneously, the crazy pointing task on output sheet and pointing out the turns in the F
-Implies the same spatial resources are being used
-Shows mental imagery works in the same way as real imagery
explain comparisons of visual imagery
Comparison of Visual Quantities
Judging size from pictures: more disparity = fast judgments
-Had to say which animal was bigger
-Same thing happens when you do it from memory
-Moyer (1973): how fast can you judge the relative size of two animals from memory
-Takes longer to estimate size when the difference is small
do visual images work like visual perception (the letter N activity and duck/rabbit study)?
-People can make judgments on imagined objects and come to the same conclusions that could be made with seen objects (Finke et al., 1989).
-Imagine a capital letter N. Connect a diagonal line from the top right corner to the bottom left corner. Now rotate the figure 90 degrees to the right. What do you see?
Chambers and Reisberg (1985)
-Briefly shown – long enough for one interpretation
Showing picture of the duck rabbit, people are only able to see one thing
-Asked to find another
-Couldn’t do it – but could after they drew it (or were given instructions on how to do it)
Implications
-They share many properties
-But it’s harder to process mental images
-Tetris – people change the shapes around even though it’s unnecessary (Krish & Maglio, 1994)
why do visual images and visual perception look the same (Include face study)
Brain areas activated by imagery correspond to brain areas activated by perception.
O’Craven and Kanwisher (2000)
-View faces and scenes, or imagine faces and scenes; both seeing and picturing these things resulted in the same activity in the brain; but less activity when you are just picturing things in the mind rather than actually looking at them
-Parahippocampal place area
-Fusiform face area
-But less activation with imagery – consistent with greater difficulty processing
is the brain activation necessary for mental imagery or is it a byproduct
Some research finds visual cortex is active during mental imagery, some does not
So are they just active, or critical?
Can use transcranial magnetic stimulation to investigate
Study
-Participants shown four different quadrants with different lines on them, were told to imagine the image when it goes away and will be asked questions about the comparative length and size between quadrants, then asked the questions again when getting TMS
-Found that it took people longer to answer questions when getting TMS
-Activation in visual cortex is allowing you to do these things, it is the cause of you being able to keep images in their brain
brain regions in mental imagery
-Temporal lobe – visual – appearance
-Parietal lobe – spatial – location
patient studies in mental imagery
-Damage to parietal – could not describe locations but could describe appearance
-Damage to temporal – could describe locations but could not describe appearance
what are cognitive maps and the two different types
Mental representations of your environment
ROUTE MAPS
-paths between locations
-Set of directions
SURVEY MAPS
-position of locations in space
-Like an actual map
-More like actual maps than route maps
-Takes a long time and experience to be able to build survey maps
