week 4 learning

Question 1

Why is learning important

Answer 1

To make predictions about events in an environment and to control them. Learning exists to allow an organism to exploit and benefit from regularities in the environment
-must know what cue to pay attention to

Question 2

How to identify if events are related

Answer 2

• Degree of contingency
–One method is to examine how often the two event co-occur
• Degree of covariation or correlation
–A second method is to consider whether the events appear together or independently

Question 3

Classical Conditioning

Answer 3

Unconditioned stimulus -> Unconditioned response
US + Stimulus -> Conditional repond (stimulus is a conditional stimulus)
US then would evoke CR on its own

Question 4

Operant Conditioning

Answer 4

Behaviouris shaped by the learner’s history of experiencing rewards and punishments for their actions.

Question 5

Positive and negative reward

Answer 5

• Positive Reinforcement = An animal will learn to produce a behaviour if the consequence of doing so is receiving something pleasant.
• Negative Reinforcement = An animal will learn to produce a behavior if the consequence of doing so is stopping something unpleasant.

Question 6

Positive and Negative punishment

Answer 6

• Positive Punishment = An animal will learn stop producing a behaviour if the consequence of producing the behavior is an unpleasant stimulus.
• Negative Punishment (response cost) = An animal will learn to stop producing a behavior if the consequence of producing the behavior is that something desirable is taken away.

Question 7

Operant Conditioning:

Blocking Paradigm

Answer 7

• A mouse have an early training of Red ligh -> Food
• Late training of red light + bell-> food and blue light + alarm -> juice
• In test, blue light + bell-> juice
• Due to early learning, bell is not registered with food

Question 8

What does blocking paradigm show

Answer 8

The Blocking effect shows that learning involves more than just monitoring co-occurrences
–If co-occurrence were the sole factor, then we would expect 50:50 responses between the food and juice in the test phase, but animals prefer the juice

Question 9

Non-associative learning:

Answer 9

Refers to processes including habituation, priming and perceptual learning

Question 10

Non-associative learning: Habituation

Answer 10

-Done through a series of exposure
– learning to ignore a stimulus because it is trivial (e.g. screening out background noises).
-because it has been learned

Question 11

Non-associative learning: Priming

Answer 11

• Prior exposure to a stimulus can improve later recognition
• demonstrated by a change in the ability to identify a stimulus as the result of prior exposure to that stimulus, or a related stimulus

Question 12

Non-associative learning: Perceptual Learning: Unitization

Answer 12

• repeated exposure of visual stimuli cause them to be perceived in chuck, not individually
• occurs when repeated exposure enhances the ability to discriminate between two (or more) otherwise confusable stimuli.

Question 13

experiment for Non-associative learning: Perceptual Learning: Unitization

Answer 13

-Task of visual search where single feature cannot aid search
- There are two conditions:
–Target is always the same: consistent mapping
–Target differs on every trial: varied mapping
When the same target is always presented, people can learn to unitize features of the target and find it very quickly

Question 14

Learning contingencies

Answer 14

Outcome Absent
Cue present a b
Cue absent c d
Delta P+ P(0?C0- P(O/-C)
=a/a+b - c(c-d)

Question 15

Delta-P

Answer 15

Delta-P is a measure of the strength of contingency between a cue and an outcome
If people learn optimally, then their responses should reflect the magnitude of Delta-P

Question 16

Are people sensitive to

Answer 16

People rate contingent associations as having a higher rating but overestimate noncontingent associations

Question 17

Bliket detection task one cause and two cause

Answer 17

One-cause condition
Red block activates the detector
Cyan brick does not activate the detector
when children is asked , red is blicket
Two-Cause Condition
-when two item activate the bliket both are consider bliket

Question 18

Bliket detection task backward and indirect

Answer 18

Backward: both objects activate, A activate by itself, when asked only A is considered
Indirect Screening: Both object active but one (B) does not activete itself. When asked, A P=1, B p=2/3

Question 19

Probabilistic contrast model

Answer 19

® Tells us that when the background is variable, we need to conditionalize on the background to understand the strength of the contingencies in the environment.
® This tells us that people are sensitive to the context in which information is presented

Question 20

Problem with delta P

Answer 20

• When the background is variable, delta-P misestimates the strength of the correlation
• The probabilistic contrast model states that we need to conditionalize on the background to understand the strength of the contingencies in the environment.

Question 21

Assumptions of the Standard Model

Answer 21

• The environment affords the existence of directional connections between pairs of elements (cause  effect)
• The elements are the mental representations of events or features of stimuli that are activated by the presence (or suggestion) of stimuli
• The presence of an element modifies the state of activation of another element
• Learning involves the strengthening of connections between elements

Question 22

The Rescorla-Wagner model

Answer 22

Red light (X) and bell (Y) acts as predictor for reward (cheese)
V is existing connection
EV: Sum of associative strengths across all stimuli
lamba is the strength of Unconditioned Stimulus
Difference between maximum strength and current strength (10-1.5) = 8.5
DeltaVx= gamma (lamda-EV)
gamma is learning rate. higer gamma or differences lead to bigger changes

Question 23

Further evidence for the role of attention in learning

Answer 23

• Blocking
–Can also be explained by RW model
• Highlighting
• Unidimensional category boundaries are easier than diagonal boundaries
–Cannot be explained by RW model

Question 24

Evidence for Attention II:

Highlighting

Answer 24

Early TrainingRed Light + Bell  Food
Late TrainingRed Light + Bell  Food
Red Light + Alarm  Juice
TestBell + Alarm Juics

Question 25

Explaination for hightlight exp

Answer 25

A and B are already paired with X
Attention is shifted to D because it alone predicts the unusual event Y
Cue D drives the final response

Question 26

Evidence for Attention in Learning:

Unidimensional Rules

Answer 26

-Subjects are shown 1 of 8 different stimuli to categorize on each trial
-Stimuli vary on their Height and the position of the inset vertical Line
two condition
-Filtration, only one condition is pay attention
-Condensation two condition must be attention
-people learn filtration faster than condestion

Question 27

Learning is a balance of belief and data (what is belief and what is data)

Answer 27

-Data is the evidence of associations in the world

• If your beliefs are very strong, you need more evidence before you’re willing to change your beliefs

Question 28

Two ways in which prior knowledge

influences our hypotheses

Answer 28

• Holmesian Deduction - Once you eliminate the impossible, whatever remains, however improbable, must be the truth
–Only hypotheses which explain the data are plausible candidates for an explanation
• Judicial Exoneration - If one suspect confesses, then we let the other suspect go
–If one hypothesis clearly explains the data, then other candidates are considered less likely