Topic 4: perception

Question 1

Define perception

Answer 1

• Process that allows us to give meaning to info provided by sense = experience world around us
• ‘Our most prominent action control device’
• Done by brain = senses just raw data

Question 2

Define illusion + 3 types

Answer 2

• Effect of misinterpreting data
  1) Geometric illusion
  2) Ambiguous figures
  3) Fictitious percepts

Question 3

Describe geometric illusion

Answer 3

• Image displayed appears distorted
• E.g. Ponzo illusion of train track = top line looks longer than bottom = exact same size

Question 4

Describe ambiguous figures

Answer 4

• Image can be seen in more than 1 way
• E.g. Necker cube + dress test + bunny/duck
• Both images can be seen but brain perceives the image related to cues heard 1st/image more familiar with

Question 5

Describe fictitious

Answer 5

• Seeing something not actually there

Question 6

Explain visual constancies

Answer 6

• Allow us to see things as remaining the same even though physical is constantly changing
• Shape constancy = ability to perceive shape of an object as constant even if it changes e.g. open door is still rectangular in shape
• Color constancy = ability to perceive color as constant even if it appears to change e.g. in lighting

Question 7

Describe Gestalt rules

Answer 7

• Form perception: figure-ground relationship = organize + simplify scene into main figures + surrounding ground they stand out against
• Minds transform stimuli into coherant by following rule:
• Grouping
• Similarities
• Continuity
• Connectedness

Question 8

Define similarity

Answer 8

• Things that share visual characteristics such as shape + size + color + texture + orientation = belong together

Question 9

Define continuity

Answer 9

• Tendancy of people to organize visual elements into unified wholes

Question 10

Describe depth perception

Answer 10

• Ability of eyes + brain to add 3rd dimention to what we see
• Depth cues = allow us to add 3D
  DEPTH CUES:
• Linear perspective
• 2 heights in plane
• Relative size
• Superimposition/overlap
• Texture gradients

Question 11

Define linear perspective

Answer 11

• Parallel lines come together at distant point

Question 12

Define 2 heights in plane

Answer 12

• If image is higher to eye = further away than lower object

Question 13

Define relative size

Answer 13

• When we expect things to be the same size and they are not = meaning further away

Question 14

Define superimposition

Answer 14

• When we can’t see a whole object as something is in front we interpret as it is further away

Question 15

Define texture gradients

Answer 15

• We can see the details of objects that are close but details fade further away

Question 16

Explain the constructivist theory

Answer 16

• We construct our perception of the world based not only on what is seen + past experiences
• Supported by top-down processing + perceptual set
• Top-down processing = perception what we expect to see
• Perceptual set = perception based on expectations

Question 17

What are the criticisms of the constructivist theory?

Answer 17

If perception is based on personal experiences:
- Why do we perceive things the same
- How does it explain a newborn’s ability to perceive
- Why do we fall for illusions over and over if we use experience to build perception

Question 18

Explain the Nativist theory

Answer 18

• Perception is result of bottom-up processing = perception is immediate + direct
• We perceive the world as it is not based on expectations
• Role of mind is only analyze info coming through eyes