L4 (week 11)- Perception

Question 1

What does sensation refer to and how does perception differ from this?

information reaching our….. preception is our …… of the sensory info

Answer 1

Sensation is the information reaching our sensory organs in energy form and perception is our analysis of the sensory information to internally describe the surrounding environment.

Question 2

What is the top-down approach?

Background influence

Answer 2

Influences of background knowledge we already hold, guided by internal intentions.

Question 3

What is the bottom-up approach?

Answer 3

Beggining with environment/stimuli (sensations)

Question 4

What are the 2 main points of ecological approach to perception?

Answer 4

That we should focus on real environments not 2D stimuli, and that all neccesary information can be picked up from the environment.

Question 5

What was found in Gibson’s 1947 study regarding picture performance tests in pilots?

how did tests relate to actual perrformance?

Answer 5

That the test results didn’t relate to actual performance at all.

Question 6

What is meant by ‘ecological optics’?

direct/indirect

Answer 6

That experiments with 2D stimuli (indirect) for example, are not helpful and that experiments need to involve the environment directly (direct).

Question 7

What is meant by ‘ambient optic array’?

the S of light reflecting

Answer 7

This is the structure of light reflecting off surfaces.

Question 8

What is an invariant?

consistant

Answer 8

something that is unchanging/constant over time

Question 9

What is an affordance?

a banana affords being eaten

Answer 9

Something we see that provides us with information about an object (like how all chairs are different but we can tell its a chair just by looking at it).

Question 10

What was Holway and Boring’s 1941 study on and what did they find?

size

Answer 10

Size distance invariance; they found that perceived size relates directly to perceived distance.

Question 11

What was Gibson’s study in 1979 suggesting and is it supported now?

light tells us what? what does it discount?

Answer 11

That patterns of light directly afforded the use of objects, this view is controversial as it discounts any knowledge held by the individual viewing the object.

Question 12

What are the 2 key principles of constructivism?

1 - info from sensations are….
2 - therefore we need….

Answer 12

That information from sensations are incomplete and imperfect AND therefore we need perceptual knowledge to unconsciously construct our perceptions.

Question 13

Name 2 illusions and their author and year.

1) face (G)
2) K illusion (k)

Answer 13

1) The hollow face illusion (Gregory, 1970)
2) Kanisza illusion (Kanisza, 1955)

Question 14

What are 2 examples of experimental evidence for top-down processing?

the C S effect
the O S effect

Answer 14

1) The configural superiority effect
2) the object superiority effect

Question 15

What is the object superiority effect?

Object > no object

Answer 15

That we recognise things that are part of an object better than when they are on their own.

Question 16

What is the configural superiortiy effect?

context/arrangement

Answer 16

that we are better at recognising objects by their context/arrangement (what they are put near).

Question 17

Regarding top-down and bottom-up approaches, which is currently the most accepted?

Top? bottom? both?

Answer 17

Integrated views of both are most commonly considered now.

Question 18

What does ‘Gestalt’ refer to?

what do we use to gain knowledge on the world around us? S + PE

Answer 18

That we use our senses and previous experiences to gain knowledge about the world around us.

Question 19

What are the 5 ‘Gestalt’ laws of organisation?

(how we perceive objects) P, S, C, GC, CF

Answer 19

1) proximity
2) similarity
3) closure
4) good continuation
5) common fate

Question 20

What do the 5 gestalt laws mean?

P, S, C, GC, CF
C: gaps
GC: break
CF: speed

Answer 20

1) proximity - elements that are close together are seen to group together.
2) Similarity - elements that are similar are perceived as grouping together.
3) closure - filling in the gaps of incomplete objects to see them as whole
4) good continuation - no perceived break in continuation where objects intersect.
5) common fate - objects moving in the same direction and speed are perceived as a group.

Question 21

What are 3 fault’s with Gestalt’s principles?

are they complex? are they helping to progress? what dimension does it apply to?

Answer 21

1) Viewed as too simplistic
2) descriptive in nature not predictive
3) only applies to 2D NOT 3D displays.

Question 22

What are the 5 constraints (dictated factors) of object recognition?

1) speed
2) viewpoint
3) new example
4) hidden
5) noise

Answer 22

1) recognition occurs rapidly: we can quickly identify an object
2) objects can be recognised from novel viewpoints
3) New examples of a know object can be recognised: we can recognise a chair even if we have not seen that style of it before.
4) occluded objects can still be recognised: a car parked behind a wall can still be seen as a car even if a small part is showing.
5) Objects can be recognised depsite visual noise: we can still see what an object is regardless of how many other objects surround it.

Question 23

What does viewer-centered representations suggest about how we determine objects?

many versions, angles, matching process

Answer 23

The idea that we hold multiple representations of an object in our mind that capture the appearance of an object including viewing angles. We rotate object in our mind until it ‘matches’ one of our pre-existing examples.

Question 24

What does object-centered representations suggest about how we determine objects?

how many forms? based on S of I. do viewpoints matter?

Answer 24

The idea that objects are represented in unitary form based on its shape of importance, viewpoints are irrelevant (therefore object-centred).

Question 25

Is the object-centered (Biederman & Cooper, 1991) or the viewer-centered (Tarr & Bülthoff, 1995) approach most accepted now?

recent evidence suggests:BLANK, however BLANK by F&G 2 is emerging.

Answer 25

Recent evidence suggests viewer-centred however an integrated approach is emerging (Foster & Gibson, 2002).

Question 26

What is meant by cross-modal associations?

making connections we subconsciously may not understand the route of (this shape is sour)

Answer 26

We automatically make associations across ‘modes’ in ways that we are often unaware of. For example being able to describe a physical shape as sweet or sour because of unconscious associations we have.