Exam 3 Chapter 10 Flashcards
Mental Imagery
- conscious sensory experience in the absence of sensory input
- visual image is one type
- “perceiving” (seeing, hearing, smelling, etc.) in the absence of a stimulus
History of study of mental imagery [placeholder]
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Galton… What’s wrong with just using introspection
People may vary in how they translate their mental imagery into verbal reports
- Not everyone has the same mental image of something like a car
Chronometric Studies… What is the thing being measured?
- It measures time
- Procedure: Form a mental image, then DO something with it
DV: Reaction time
Spatial Representation (depcition theory)
Mental image is like a picture
Same kind of representation as perception
Propositional (Description) Theory
Mental image is actually a set of rules describing the picture. It might feel like perception, but it is not
Proposition - statements about some object or event in the universe (a concept), either naturally occurring or constructed
Studies [placeholder]
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Mental Imagery vs categories (Kosslyn, 1976)
Form a mental image of a cat and answer the question if it has a head, then answer the qusetion if it has claws
Think about the concept of cats then answer the question if it has a head, then answer the question if it has claws
The depiction/mental image representation was slower to identify if a cat has claws since you have to look closely at the picture in your head
The description/proposition representation identified the head slower since We go through the hierarchy of the semantic network in our heads. Claws would be stored in the cat category since not all mammals or animals are heads. Since all mammals have heads its further up in the hiearchy in the semantic network which takes longer for us to navigate form the cat node to the animal node
Both theories prove themselves right in this study
Mental scanning part 1 for Depiction Theory Kosslyn (1973)
The question is when someone has a mental image in thei head, does it take them longer to get to something that is further away?
- It did! RT was faster for parts closer together
- The Spatial Representation Theory (depiction) suggests that maybe mental images are like pictures?
Mental Scanning part 2 Descirption theory
- Propositin theory (depiction) states that you would get the same reults from a propositional mental representation too!
- You can have a set of statements that represents the configuration of a boat in a hierarchial way in where things are on the boat
- They got the same data indeed
Mental Zooming Kosslyn (1975)
Imagine a rabbit next to a fly
Does the rabbit have a pink nose?
Imagine a rabbit next to an elephant
Does the rabbit have a pink nose?
- Spatial representation (depiction) theory states that if mental imagery is picture-like, you would have to “zoom in” to see the rabbit’s nose, and that should take more time next to the elephant
Results: fly next to rabbit was faster than elephant next to rabbit. This is supporting evidence for depiction theory to state that mental imagery seems to be like perception
Mental Rotation Shepard & Metzler (1971)
IV: how far you have to rotate one shape to compare to the other (degrees of rotation)
DV: RT
Spatial Representation (depiction) theory says mentally rotating the images take time just like physically rotating them would. This suggest mental imagery is like perception
Brain data
What the brain tells us about how mental imagery works
Tells us what extent the same brain areas are used for imagery and perception
- Single cell recording
- fMRI
Brain data: single-cell recording Kreiman et al. (2000)
- Some epilepsy patients already had some electrodes inserted into their brains
- Procedure:
–Show them a picture of a baseball, record neuron firing pattern
– Show them a picture of a face, record neuron firing pattern
– Ask them to form a mental image of a baseball, record neuron fiting pattern
– Ask them to form mental image of a face, record neuron firing pattern
Results: When told to imagine the baseball and face, the neurons fired in similar patterns compared to when the patients saw the pictures
This supports depiction theory that says visual areas in the brain should be active
fMRI Le Bihan et al. (1993)
- Participants are shown patterns, or told to imagine them
- Primary visual cortex activity recorded using fMRI
- The visual cortex lights up when they imagined seeing what they were told
- No other part of the brain responded
Results: Visual imagery appears to happen in the brain areas that are responsible for actual vision. This supports Spatial Representation (depiction) theory
