thinking lectures 1 and 2 recap notes on bayes when studying this!

Question 1

what is thinking?

Answer 1

process in the mind

organisation and manipulation of internal representations

Question 2

which debate shows how different representations are formed?

Answer 2

rationalism vs empiricism

Question 3

what is rationalism?

Answer 3

reason is enough for knowledge

Question 4

what is empiricism?

Answer 4

knowledge should be created through obeservation and experience

importance of sensory observations

Question 5

what do algorithms suggest about thinking?

Answer 5

perception doesnt directly map the physical world to the mind

instead it is an inference process, and the brain uses algorithms to construct an image of the world

Question 6

how does the brain use integration for thinking?

Answer 6

integrates specific observations with different contextual information

Question 7

what can interpretations depend on?

Answer 7

what we are primed with

Question 8

what are the two opposing ideas for how human cognition works?

Answer 8

human cognition is based on Bayesian algorithms

OR

humans fail to take prior probabilities/base rate into account

Question 9

what is Bayes formula for inference?

Answer 9

p(H1|O)= (p(H1)xp(O|H1))/p(O)

Question 10

what does p(O|H1) mean?

Answer 10

probability of a certain observation O given that hypothesis B1 was true
(true positive)

Question 11

what does p(H1) mean?

Answer 11

prior probability of hypothesis H1 being true

Question 12

what does p(O) mean?

Answer 12

prior probability of making observation O
(positive)

Question 13

what does P(H1|O) mean?

Answer 13

posterior probability of H1 being true given observation O being made

Question 14

what do we use Bayes’ theorem for?

Answer 14

the likelihood of perceptions occuring

Question 15

how can Bayes’ theorem be used for senses?

Answer 15

can derive how senses are combined to result in a common judgement

Question 16

what happened when Ernst and Banks (2002) investigated perception?

Answer 16

VR task

compared the heights of two bars

can measure the accuracy of judgement in the visual and somatosensory domain

in combined perceptions, judge how much their judgement depends on visual vs haptic perception

Question 17

what does the psychometric function do?

Answer 17

relates an observer’s performance to an independent variable

Question 18

how do psychologists use the psychometric function to assess perceptions?

Answer 18

ppts had to judge whether a second stimulus was larger than the first

different ppts have different sensitivities to the difference

psychometric function often modelled as a cumulative function/S shape

better performance=steeper curve

Question 19

how did Ernst and Banks (2002) investigate the psychometric function?

Answer 19

had a standard and comparison stimulus

measured the psychometric function- haptic stimulation only/visual stimulation/at different noise levels

get different psychometric functions for the different conditions

Question 20

what sense is haptics?

Answer 20

touch

Question 21

did Bayes theorem predict how visual and haptic stimuli were used?

Answer 21

yes, predicted how they were used for optimum perception

people benefit from combining information

Question 22

what did Stocker and Simoncelli (2006) investigate?

Answer 22

looked at noise characteristics and prior expectations in human visual speed perception

Question 23

how did Stocker and Simoncelli investigate visual speed perception?

Answer 23

presented moving gabor patches/gratings at different speeds or contrast levels

Question 24

what hypotheses did Stocker and Simoncelli have when investigating visual speed perception?

Answer 24

low contrast stimuli will be perceived as more ambiguous

ppts will be biased to perceive motions as slower than they are

perceived motion of low contrast gratings will be slower than high contrast gratings

Question 25

what hypotheses did Stocker and Simoncelli have when investigating visual speed perception?- were these hypotheses confirmed

Answer 25

yes
the Bayesian observer model explained the behavioural data for different motions speeds and contrasts well and better than other models

Question 26

what is a criticism of Ernst and Banks’ study?

Answer 26

didn’t investigate whether participants integrate sensory signals and prior probabilities

Question 27

what is a criticism of Stocker and Simoncelli’s study?

Answer 27

didn’t manipulate the prior probabilities- only estimated them