Perception - Mock Flashcards
Strength of Gibsons theory - real world meaning
One strength of Gibsons theory is that it has real world meaning
Resear h was based on the experience of pilots from the second World war
This makes it more relevant to explaining how we perceive the world on a daily basis
Weakness of Gibsons theory - struggles to explain visual illusions
One weakness of Gibsons theory is that it struggles to explain visual illusions.
Gibson proposed that we will always perceive accurately whereas illusions trick the brain into misperception.
This suggests there is more to perception than his theory proposed.
Strength of Gibsons theory - support for the role of nature
Another strength comes from Gibson and walks study.
Very few infants would crawl off a visual cliff
This suggests that infants have an innate ability to perceive depth, which shows that some perception is innate.
Visual illusions explanations
Misinterpreted depth cues
Ponzo illusion - converging lines give the illusion of distance. The brain uses size constancy and mentally scales up the more distant line while mentally scaling down the closer line
Muller lyer illusion - outgoing fins stretching away from us, ingoing fins projecting out-gives illusion of distance, we mentally scale up the line that appears closer so it appears longer.
Ambiguous figure
Necker cube - the same image of a cube can be perceived as pointing upwards to the right or downwards to the left.
Fiction
Kaniza triangle - illusory contours to create the impression that a second triangle is overlapping the first one
Factors affecting perception - ambiguous figures
Expectation - the belief about what is likely to happen based on past experiences can affect how much we attend to or notice things in the environment. - participants were presented with a sequence of letters or numbers, at the end they were presented with an ambiguous figure that could be seen as either the letter B or the number 13.
Those who saw letters were more likely to say it was a B and those who saw numbers were likely to say 13
Culture affecting perception
Hudson aimed to find out whether people from different cultural/educational backgrounds perceived depth cues in 2D images differently.
South Africans were shown 2D drawings - native black people and white Europeans.
Participants had to say which animal the man was trying to spear.
Depth cues suggest the spear was being aimed at the elephant. Schooled participants were more likely to perceive depth than jnschooled participants. White schooled participants were more likely to perceive depth than black schooled participants.
People from different cultural/educational backgrounds use depth cues differently and have a different perceptual set. This supports Gregory’s theory as it shows that depth cues are learned.
Strength of lab experiments
Evs can be controlled. Therefore researcher can be sure the IV caused the DV. Cause and effect can be established.
Stabdarsied procedures can be used. So study can be replicated. Can test validity of results.
Weakness of lab experiments
Environment is not like everyday life. So participants behaviour is less typical. Can’t generalise results to wider world.
Participants may know they are being tested and change behaviour to help experimenter. This means data may not be valid
Size constancy
The brain perceives familiar objects as a constant size despite the size of the image they produce in our retina changing the distance
Misinterpreted depth cues
Objects in the distance that appear smaller are scaled up by our brain so they look normal size. Sometimes the brain sees distance when there isn’t any which creates a visual illusion as In the following two examples.
Muller lyer illusion
Outgoing find are shaped like the inside corner of a room which is stretching away from us. Ongoing fins are shaped like the outside of a building projecting out. Gives the illusion of distance mentally scale up the line
