Psya3 Perception - Gibson And Gregory

Front 1

Gibson's Bottom Up direct theory of perceptual orgainsation

Back 1

senses
optic array
optic flow
invariants
texture gradient
Motion parralax
Affordance

Front 2

Gregory's top down theory of perceptual organisation

Back 2

infomration we already know
hypothesis and test
stored knowledges guides perception
we act as scientists , forming and testing hypotheses about the world around us

Front 3

Evaluation of Gibson's theory

Back 3

1) The Cat
2) hear everything the same
3) percieve all objects the same
4) perceptual set theory - cannot explain this, items between A and C to be perceived the same irrespective of context.
5) positive - senses can interpretate things in two different ways. Necker cube - visual illusions.
6) posistive - visual illusions are created by psychologists and are not like real life

Front 4

Evaluation of Gregory's theory

Back 4

1) The cat - evidence we use context in perceiving things
2) Hearing familiar and unfamiliar things "recognise speech" "wreck a nice beach" we would know which one someone said based on context of conversation
3) perception of an object - wooden box
4) perecptual set theory - you read A B C not (13) because you perceptually 'sets' you to read ABC.
5) the cube appears to flip or change. this is because we are trying to make sense of what we are seeing based upon our experience of the world. both perspectives are just as likely and therefore both appear.
6) we do get ambigious things in the real world e.g. shadow in the forest, so visual illusions can be applied.

Front 5

Marr's computational model

Back 5

Primal sketch
2 1/2 D sketch
3-D model

Evaluation of Marr's is that it does not process happens it just does
he also fails to explain the subtle abilities we have e.g. the model can explain how we identify diferent classes of objects such as trees but cannot tell us how we can identify individual items such as the tree in our garden.