Chapter Three - Perception

Question 1

What is perception?

Answer 1

-experience resulting from stimulation of the senses

Question 2

What are 3 basic concepts of perceptions?

Answer 2

1. perceptions can change based on added info
2. involves a process similar to reasoning/problem solving
3. occur in conjunction with actions

Question 3

Is human perception unique to humans?

Answer 3

• possibly, yes

- AI has failed to match level of perception

Question 4

What is the inverse projection problem?

Answer 4

• task of determining object responsible for a particular image on retina
• involves starting with retinal image
• then extending outward to source of that image

Question 5

Why is perception so difficult for a machine? (2)

Answer 5

1. objects can be hidden or blurred

2. objects look different from different viewpoints (viewpoint invariance)

Question 6

what is bottom-up processing?

Answer 6

• start at bottom of system

- environmental energy stimulates receptor

Question 7

what is top-down processing?

Answer 7

• originates in brain
• top of perceptual system
• previous knowledge affects perception

Question 8

What are direct perception theories?

Answer 8

• bottom-up processing
• perception starts with the senses
• parts are put together

Question 9

What are constructive perception theories?

Answer 9

• top-down processing

- people actively construct perceptions using info based on expectations

Question 10

What is an example of how top-down processing is involved in perception of objects?

Answer 10

-blurred blobs are identical but perceived as different objects due to orientation + context

Question 11

What is speech segmentation?

Answer 11

-ability to tell when one word ends and another begins

Question 12

How is top-down processing involved in speech?

Answer 12

• hearing words in a sentence in a foreign language

- ability to pick out certain words based on context

Question 13

What is the direct pathway model of pain?

Answer 13

• early model, emphasized sensory receptors that send pain messages directly to the brain
• bottom-up processing model

Question 14

What pain phenomenon challenges bottom-up processing of pain?

Answer 14

the placebo effect

Question 15

What is Helmholtz’s Theory of Unconscious Inference?

Answer 15

• top-down theory
• some perceptions are result of unconscious assumptions we make about environment
• most of what we know about the world is an inference

Question 16

What is the likelihood principle?

Answer 16

-perceive the world in way that is “most likely” based on our past experiences

Question 17

What is the “Old” view of perceptual organization?

Answer 17

• structuralism

- perception involves adding up sensations

Question 18

What is the new view of perceptual organization?

Answer 18

Gestalt psychologists

Question 19

What do Gestalt psychologists believe?

Answer 19

-mind groups patterns according to laws of perceptual organization

Question 20

What is apparent movement?

Answer 20

• movement is perceived even though nothing is moving

- whole is different than sum of its parts

Question 21

What are the 3 Gestalt Laws of Perceptual Organization?

Answer 21

1. Law of good continuation
2. Law of pragnanz (simplicity/good figure)
3. Law of similarity

Question 22

What is the law of good continuation?

Answer 22

-lines tend to be seen as following the smoothest path

Question 23

What is the law of pragnanz?

Answer 23

-every stimulus pattern is seen so resulting structure is as simple as possible

Question 24

What is the law of similarity?

Answer 24

-similar things appear grouped together

Question 25

Gestalt laws often provide accurate information about properties of _________

Answer 25

the environment

Question 26

Where do the Gestalt Laws come from?

Answer 26

- intrinsic | - role of experience is minor

Question 27

What do modern perceptual psychologists believe?

Answer 27

-perception is influenced by knowledge of regularities in environment (agreement with Helmholtz)

Question 28

What are physical regularities?

Answer 28

regularly occurring physical properties

Question 29

What are semantic regularities?

Answer 29

-characteristics associated with the functions carried out in different types of scenes

Question 30

What is the oblique effect?

Answer 30

-people can perceive verticals + horizontals more easily than other orientations

Question 31

What is the light-from-above assumption?

Answer 31

- light comes from above | - perceive shadows to inform us about depth + distance

Question 32

What is a scene schema?

Answer 32

-knowledge of what a given scene ordinarily contains | EX: professor's office

Question 33

What is perception according to the inferential approach?

Answer 33

- given an image (input) + the knowledge about regularities of physical world - pick most probably interpretation of image

Question 34

What is Bayesian Inference?

Answer 34

- one's estimate of the probability of a given outcome is influenced by 2 factors: 1. prior probability 2. likelihood of a given outcome

Question 35

What are the 4 approaches to perception?

Answer 35

1. Helmholtz's unconscious inference 2. Gestalt Laws of organization 3. Regularities in the environment 4. Bayesian inference

Question 36

Which of the 4 approaches to perception are bottom-up? Top-down?

Answer 36

Bottom-Up: Gestalt Laws of Organization Top-Down: Helmholtz's unconscious inference regularities in environment Bayesian inference

Question 37

What do modern psychologists claim about the Gestalt Laws?

Answer 37

laws could have also been created by experience

Question 38

What happens to neurons over time?

Answer 38

-become tuned to respond best to what we commonly experience

Question 39

Why is it beneficial that neurons be atuned to stimuli over time?

Answer 39

- natural selection | - neurons can be trained to respond to specific stimuli

Question 40

What is experience-dependent plasticity?

Answer 40

mechanism through which the structure of the brain is changed by experience

Question 41

How did Blakemore and Graham Cooper demonstrate plasticity?

Answer 41

- raised kittens in space in which they only saw vertical black + white stripes on walls - visual cortex had been reshaped

Question 42

experience-dependent plasticity plays a role in activation of the _________

Answer 42

fusiform face area (FFA)

Question 43

What happened after "Greeble recognition?"

Answer 43

-FFA fired as much for Greebles as it did for faces

Question 44

_____ helps us perceive things in our environment more accurately than static images

Answer 44

movement

Question 45

What are the 2 processing streams?

Answer 45

- what stream: identifying an object | - where stream: identifying object's location

Question 46

What two methods were used to discern the two processing streams?

Answer 46

1. brain ablation | 2. neuropsychology

Question 47

How did Ungerleider and Mishkin study about the what and where pathway?

Answer 47

-studied how removing part of a monkey's brain affected its ability to identify an object + determine its location

Question 48

What is object discrimination?

Answer 48

- monkey shown object | - must pick correct object

Question 49

What is landmark discrimination?

Answer 49

- cylinder indicates which side monkey's food is on | - location

Question 50

The temporal lobe controls which pathway?

Answer 50

where/dorsal

Question 51

The occipital lobe controls which pathway?

Answer 51

what/ventral

Question 52

What did Milner and Goodale find?

Answer 52

- studied 34 year old woman with damage to temporal lobe - asked to rotate card - asked to mail a card

Question 53

Is the psychological repertoire universal?

Answer 53

no