Unit 7

Question 1

Perception as a mental process

Answer 1

Interpretation of events and objects

Question 2

Perceptual process

Answer 2

Series of stages of mental processes that result in perception

Step 1: The distal stimulus
Step 2: The proximal stimulus
Step 3: Receptor processes
Step 4: Neural processing
Step 5: Perception
Step 6: Recognition
Step 7: Action

Question 3

Step 1: The distal stimulus

Answer 3

Stimulus in environment
-> beginning of perceptual process
Perception based on effect that stimulus produces on senses (e.g. light reflected, sound waves created, etc:)

Question 4

Step 2: The proximal stimulus

Answer 4

In the case of visual perception: image projected on retina
-> due to proximity to visual receptors
Final perception caused by activity on visual receptors produced by proximal stimulus

Question 5

Step 3: Receptor processes

Answer 5

Sensory receptors convert proximal stimulus into electrical energy
Transduction (transformation of any stimulus into electrical signal)

Question 6

Sensory receptors

Answer 6

Cells specialised to respond to a specific type of energy (e.g. light, pressure, etc.)

Question 7

Step 4: Neural processing

Answer 7

Neurones transmit electrical signal to different areas of the brain

Question 8

Step 5: Perception

Answer 8

Perception: conscious awareness and interpretation of a stimulus

Question 9

Step 6: Recognition

Answer 9

Recognition: placing object in category that gives it meaning

Question 10

Step 7: action

Answer 10

Final behavioural response
Involves some kind of motor activity

Question 11

What are steps 5, 6 & 7 known as?

Answer 11

Behavioural responses

Question 12

Whats important about the sequence of the steps of behavioural responses?

Answer 12

Doesn‘t need to happen in linear fashion

Question 13

The role of knowledge in perceptual processes

Answer 13

Previously acquired knowledge stored in memory influences the perception of objects
-> influences category the stimulus is assigned to

Question 14

Top-down perceptual processing:

Answer 14

Aka constructive perception
Previously experienced things and expectations guide stimulus
-> sensory stimulation forms basis of perception
-> other sources of information (e.g. previous knowledge) used to construct perception

Question 15

How can constructive perception be studied?

Answer 15

Taking a look at implicit memory
-> knowledge and expectations help interpret stimuli (even when incomplete or distorted)

Question 16

What did Hermann von Helmholtz study?

Answer 16

Perception according to constructive perspective

Question 17

Which idea did Helmholtz propose?

Answer 17

Idea that knowledge of physical and semantic regularities can help unconsciously infer whats happening

Question 18

What is Helmholtz‘ perspective based on?

Answer 18

The likelihood principle
(Condition: image projected on retina is ambiguous)

Question 19

What is the likelihood principle?

Answer 19

What we perceive reflects the object that is most likely to have caused the retinal image

Question 20

What does unconscious inference in the context of our perception mean?

Answer 20

Perceptions are result of automatic assumptions made about environment based on previous experiences and knowledge

Question 21

Who is an important defender of the idea of bottom-up perceptual processes and what was his theory called?

Answer 21

James J. Gibson
Theory of direct perception

Question 22

What does the theory of direct perception suggest?

Answer 22

Activation produced in sensory receptors: all thats necessary to create perception
=> no need for top-down influences
=> perception direct reflection of stimulus

Question 23

What is the ecological approach?

Answer 23

Says that environment supplies us with all information necessary for perception

Question 24

What is optic flow?

Answer 24

Travelling past an object giving the impression that it is moving

Question 25

What are the characteristics of the optic flow?

Answer 25

1. more rapid near moving subject 2. no flow at destination toward which subject moves -> focus of expansion

Question 26

Ecological approach and Gibson and colleagues‘ research methods

Answer 26

Ecological approach drove research methods Traditional approach (lab experiments) lack ecological validity -> dont capture perceptual experiences in real world Perception studied in situations in which people move through and interact with environment Major goal: understanding how movement creates perceptual information that guides movement and helps in perception of environment

Question 27

Are bottom-up and top- down theories entirely contradictory?

Answer 27

Contradict each other However also complementary -> in some occasions sensory information is rich and unambiguous (little top-down control) -> in some sensory information degraded and ambiguous (more top-down control)

Question 28

Goldstein‘s view on perception:

Answer 28

„ an interaction between bottom-up processing, which starts with the image on the receptors, and top-down processing, which brings observer‘s knowledge into play“