Perception Flashcards
Gregory’s theory?
Constructivist. He believes sensation and perception are very different things. He believes perception is a construction using schemas, past experience and your sensation and building this to make an inference of something you sense
Gibson’s theory?
Direct. He determines no difference between sensation and perception. He believes you get all the information needed to perceive something with senses only.
What is sensation?
Sensation is detected by sense receptors and allows us to experience the world around us: 5 senses(hear, touch, taste, sound, sight)
What is perception?
Perception is the way you process and make sense of your senses. You interpret sensory information using past knowledge.
Difference between sensation and perception?
Sensation is how we detect stimulus in the environment, the ‘feeling’. Perception is how we interpret it, the ‘thinking’ part.
What are the two theories of perception?
Gregory’s constructivist and Gibson’s direct
Ponzo illusion explained?
Misinterpreted depth cue
The vertical lines that come in make the top horizontal line look longer than the bottom.
Muller-Lyer illusion explained?
Misinterpreted depth cue
Fins going outward make the line appear longer, fins facing inward make the line appear shorter
Rubin’s vase explained?
Ambiguous figure
Can be seen as two faces or a vase, brain switches between the two images
Ames room explained?
Misinterpreted depth cue
Room is a trapezoid shape, making it appear as if one person is a giant whilst the other is very small
Binocular depth cues?
Retinal disparity, convergence
Retinal disparity?
Each eye is a few cm apart so each eye gets a slightly different view of the world. The closer the object, the bigger the difference of the two images, the further away the object, the more similar the two images will be.
Convergence?
When an object is closer our eyes come together. When an object is further away , our eyes are more straight when looking at it. When your eyes go in to look at something closer, the muscles have to work harder. This muscle information provides our brain with information about depth of what we’re looking at.
Monocular depth cues?
Height in plane, occlusion, relative size, linear perspective
Height in plane?
When something is further away it appears to be higher up than things that are closer. Our brain interprets depth using this.
Relative size?
Things further away seem smaller and things closer up seem bigger. By our brain knows their real size so interprets depth using this.
Occlusion?
Things further away get obscured by closer objects. The brain interprets depth through this.
Linear perspective?
Parallel lines appear to get closer in the distance.
Size constancy?
Size constancy is when an object appears smaller further away but our brain knows it’s size stays constant.
Gibson’s direct theory?
Gibson says sensation gives us all the information we need to perceive and that sensation and perception are the same. We do not need past experience to put things together to make sense of our sensations and perceive.
Gibson’s direct theory: optic flow patterns
When we move, the point we are moving towards stays stationary while the rest of the view seems to rush away from it. These optic flow patterns detect depth, movement etc.
Gibson’s theory: motion parallax
He said motion parallax is another depth cue, when in the car, things further away seem to be moving slower but when you move past it it seems to be moving much faster.
Gibson’s direct theory evaluation?
S-Gibson’s theory developed through real life things like pilots in ww2, helps us understand things like depth, speed
W-Struggles to explain perceptual error
S-backed up with research into infants, reluctant to crawl off fake cliff
Gregory’s theory evaluations?
S-supporting research into cultural differences in perceptual set
W-helps understand visual illusions but those aren’t useful in understanding perception in everyday life
W-can’t explain examples of innate perception
Factors affecting perception?
Culture, emotion, expectation, motivation
Gilchrist and Nesbergs aims?
Aimed to find out the effect food deprivation would have on perception of food related pictures. Would they appear brighter?
Gilchrist and Nesbergs study?
26 undergraduates volunteered to go without food for 20 hours. There was a control group not deprived of food, they were randomly allocated to conditions. Shown 4 slides of different meals for 15 seconds. They had to adjust the brightness of a dimmer version of the pictures to match the picture they had seen
Gilchrist and Nesbergs results?
The group that was food deprived adjusted the brightness higher than the control group. They suggested the food was brighter than the real picture, the same effect didn’t occur with the control group.
Gilchrist and Nesberg conclusions?
Suggest hunger is a motivating factor that effects perception. Heightens sensitivity to food and effects perceptual set.
Gilchrist and Nesbergs evaluations?
S-similar studies found similar results
W-ethical issues
W-not like everyday life
Bruner and minturns study aims?
Aimed to find out if the context of a stimulus was perceived differently depending on the context it is presented in
Bruner and Minturns method?
Independent groups design, shown the same stimulus which can be read ‘13’ or ‘B’. Shown in either sequence abc or 12 13 14. Participants had to draw what they saw.
Bruner and minturns results?
If presented in letters, more likely to view as B. If presented in number sequence, more likely to be viewed as 13.
Bruner and Minturns conclusions?
Expectation has an important influence on perception. Context affects perception.
Bruner and Minturns evaluations?
W-artificial task
W-independent groups design
S-explains why people make perceptual errors
