Perception 3

Question 1

What does visual input provide?

Answer 1

Ambiguous information about the 3D structure of the world

Question 2

What does image complexity do for computers?

Answer 2

Makes it increasingly tricky for computers to organise the visual scene into distinct objects

Question 3

What can we infer with Monocular cues (one eye)?

Answer 3

Relative height, relative size and shadows

Question 4

What can we infer with Binocular cues (both eyes)?

Answer 4

Disparity

Question 5

Where are objects if they are typically perceived as being more distant?

Answer 5

Below the horizon and have their bases higher

Question 6

If two objects are of equal size the more distant one will take up more or less of your field of view?

Answer 6

Less

Question 7

What happens to texture elements when distance increases?

Answer 7

They get smaller and more dense with distance

Question 8

What happens to circles when the surface is tilted away?

Answer 8

Foreshortening (circles become ovals)

Question 9

Define motion parallax

Answer 9

As we move, more distant objects will glide past us more slowly than nearer objects

Question 10

What does the brightness of a surface depend on?

Answer 10

Its orientation with respect to the light source

Question 11

Define stereoscopic vision

Answer 11

Our 2 eyes receive a slightly different image of the world

Question 12

What does disparity do on image location?

Answer 12

It creates a difference in location of an object seen by left and right eyes

Question 13

What does the size of the disparity depend on?

Answer 13

Object’s depth

Question 14

What is a Horopter?

Answer 14

A set of points that project to corresponding positions in the 2 retinas

Question 15

What disparities do objects have when they are closer than the horopter?

Answer 15

Crossed disparities

Question 16

What disparities do objects have when they are further than the horopter?

Answer 16

Uncrossed disparities

Question 17

What is the process where depth information is extracted from binocular disparities called?

Answer 17

Stereopsis

Question 18

What is Structuralism?

Answer 18

Proposed by Wundt; perceptions are simply the sum of ‘atoms’ of sensation

Question 19

What is the Gestalt school?

Answer 19

against structuralism led by Wertheimer, Köhler & Koffka; argued the whole form is greater than the sum of its parts

Question 20

What are illusory contours?

Answer 20

Some images evoke the perception of edges in locations where there is no change in luminance or colour- this is hard to explain with the structuralist approach

Question 21

What did the Gestalt psychologists propose?

Answer 21

Principles which elements in an image are grouped to create larger objects

Question 22

Define proximity, in terms of visuals

Answer 22

Things that are close together group together

Question 23

Define similarity, in terms of visuals

Answer 23

Things that are similar group together

Question 24

Define common fate, in terms of visuals

Answer 24

Things that move together, group together

Question 25

What helps preserve grouping of occluded objects?

Answer 25

Group elements to form smoothly continuing lines rather than abrupt/ sharp angles

Question 26

Define closure, in terms of visuals

Answer 26

Group elements to form complete figures, even if incomplete

Question 27

What makes elements more likely to be formed into groups?

Answer 27

If they are balanced or symmetrical

Question 28

What is one limitation of the Gestalt principles?

Answer 28

Some are vague and there is no coherent workable account of the underlying neural mechanisms