Form Perception

Question 1

Qualities of Gestalt Principles

Answer 1

Laws that describe how we orange visual import
Laws are innate or acquired quickly after birth

Question 2

Figure Ground Principle

Answer 2

Ability to distinguish an object from its background in a visual scene
- Figures tend to have distinct borders that give it form over the background

Question 3

Proximity Principle

Answer 3

Group elements that are close together in space
- Cluster of daisies

Question 4

Closure Principle

Answer 4

Fill in gaps in a contour to perceive whole object
- Truck behind pole

Question 5

Similarity Principle

Answer 5

Group together elements that are physically similar
- rows of vegetation

Question 6

Continuity Principle

Answer 6

Ability to perceive a simple, continuous form rather than a combination of awkward forms
- x’s as two continuous lines

Question 7

Common Fate Principle

Answer 7

Group together elements that change in the same way
- objects moving in the same direction (school of fish)

Question 8

Whole is other than the sum of its parts

Answer 8

the whole has an independent representation in the perception system and cannot be reduced

Question 9

Processing

Answer 9

enable us to create signal from noise
- Expectation shapes what we see

Question 10

Bottom-Up Processing

Answer 10

Object recognition is guided by the features that are present in the stimulus

Question 11

Bottom-Up Recognition

Answer 11

involves comparing every feature to memory
- Link features with similar features in memory

Question 12

Top-Down Processing

Answer 12

Object recognition is guided by your own beliefs or expectation
- Recognition can be primed
- Needs some input from stimulus

Question 13

Prime Experiment

Answer 13

the subject is flashed a word to read, is told next word is an animal
- Primed individuals are faster in reading

Question 14

Bi-Directional activition

Answer 14

Both top-down and bottom up processing guide object recognition
- Recognition can rely on varying degrees of processing

Question 15

Geon Theory

Answer 15

We have representative geons or geometric forms stored in memory
- Cones, cube, cylinder

Question 16

Brain Injury

Answer 16

Some deficits can be a person cannot recognize fruit but can recognize different tool
- From Geons

Question 17

Template Theory

Answer 17

We compare objects to templates in Memory
- If a match is not found, its unfamiliar and stored as a new template
- can be exhausting as you need to store many templates and sort them

Question 18

Prototype Theory

Answer 18

We compare objects to our ideal prototype
- We store the most ideal examples of an object
- Easily recognize objects never seen before

Question 19

Perceptual Constancy

Answer 19

Our ability to perceive an object as unchanging even though the visual image produced by the object is constantly changing

Question 20

Shape Constancy

Answer 20

an object is perceived to have a constant shape despite the shape of its retinal image changing with shifts in point of view or change in object position

Question 21

Location Constancy

Answer 21

An object is pierced to be stationary despite changing location on our retina due to body movements

Question 22

Size Constancy

Answer 22

An object is perceived to be the same size despite the size of its retinal image varying with distance
- Objects getting smaller as they walk away

Question 23

Brightness Constancy

Answer 23

Object is perceived to be the same brightness despite reflecting more or less light onto our retina

Question 24

Colour Constancy

Answer 24

object is perceived to have a constant colour despite different illumination conditions

Question 25

Cues Indicate

Answer 25

Depth cues: size of an object relative to distance
Colour cues: influence of a light on a objects colour

Question 26

Visual Illusions

Answer 26

Muller-Lyer: misapplied size constancy and misinterprets depth
Ames Room: manipulates distance to trick size constancy
Ponzo: manipulates depth cues to trick size constancy

Question 27

How does the brain process stimuli

Answer 27

In one region before passing it on to the next
- Feature detectors fire in response to select types of stimuli

Question 28

First step in object recognition

Answer 28

Ganglion cells

Question 29

Hodgkin & Huxley

Answer 29

Pioneered methods for recording electrical activity in neurons
Primary visual cortex –> feature detectors

Question 30

Bug detectors

Answer 30

Neurons in the optic nerve of a frog respond only to moving dots

Question 31

Hubel & Weisel

Answer 31

Some neurons fired only when the line was in a particular place on the retina
- Neuronal activity changed with line orientation
- Sometimes the neurons fired only when the line was moving in a particular direction
- Different types of stimuli (flashes) → not much response
- Crack in slide → neurons fired

Question 32

What will neurons fire to

Answer 32

Each neuron is specific about what will make it fire the most
- These neurons respond maximally to stimuli of certain shape, size, position and movement → defines the receptive field for that cell

Question 33

Simple cells

Answer 33

respond maximally to a bar of a certain orientation in a particular region of the retina

Question 34

Complex Cells

Answer 34

responds maximally to a bar of a certain orientation and direction of movement, regardless of where the bar is located within the receptive field

Question 35

Complex vs Simple cells

Answer 35

S: Responds most to horizontal bar○bar moved outside/changes orientation →cell will be inhibited and fire below baseline
C: doesn’t care about where in its receptive field the bar is located, and it will even continue to fire if the bar is moving within the receptive field

Question 36

Hypercomplex Cells

Answer 36

respond maximally to a bar of a particular orientation and direction of movement, ending at specific points within the receptive field