Week 2

Question 1

What are the two types of associative learning?

Answer 1

Classical conditioning

Operant conditioning

Question 2

Classical Conditioning

Answer 2

Ivan Pavlov

• Learning via association

Question 3

Operant Conditioning

Answer 3

B.F. Skinner

• Learning via reinforcement

Question 4

Free Energy Principle

Answer 4

Biological systems must maintain their states
despite a constantly changing environment (both
external and internal)
• The physiological and sensory states in which an
organism can be is limited - low entropy
• Entropy = surprise. a “fish out of water” has high entropy
• Biological agents must minimize the long-term
average of surprise to keep sensory entropy low.
Action or control signals, external states, sensations, internal states
Free-energy bound on surprise- action minimises prediction errors or perception optimises prediction

Question 5

Free energy principle summed up

Answer 5

Minimising surprise, or….
maximising the sensory evidence for an agent’s existence (a model of its world).
A predictive/Bayesian brain

Question 6

Classical (Pavlovian) Conditioning

Answer 6

Russian physiologist
Studied the digestive system.
Salivation.
Dogs that had been through the testing procedure several times: salivation observed before food was placed in their mouth

Learning. New stimuli.
…accidentally discovered
classical conditioning!

Question 7

Pavlov’s salivation experiments

Answer 7

When food was placed in the animal’s mouth, the natural reflexive response of salivation occurred & was measured.
A stimulus elicits an innate response
Other stimuli don’t elicit that response
However dogs that had been through the testing procedure a few times would being to salivate before food was put into their mouths. therefore the dog has learned that footsteps, clanging of food dish, bell, whistle by the experimenter means food therefore salivating

Question 8

4 elements of classical conditioning

Answer 8

1. Food (US) -> Salivation (UR)
2. Whistle (Neutral Stimulus) -> No salivation (No conditioned response)
3. Whistle + food -> Salivation (UR)
4. Whistle (CS)-> Salivation (CR)

Question 9

Definitions of the 4 elements of classical conditioning

Answer 9

Unconditioned stimulus (US)- A stimulus that elicits an unlearned response
Unconditioned response (UR)- The learned response to a US
Conditioned stimulus (CS)- A stimulus to which an organism must learn to respond
Conditioned Response (CR)- The response to a CS (which is learned)

Question 10

Steps of conditioning

Answer 10

Before- US-> UR
During- CS+US-> UR
After- CS-> CR

Question 11

Clinical applications for classical conditioning

Answer 11

Acquisition of fears, phobias, and other maladaptive behaviours.
Treatment of these same fears, phobias, and other maladaptive behaviours.

Question 12

Conditioned fear- Watson & Rayner

Answer 12

Little Albert
Acquisition of emotional responses- loud noise and mouse
generalised fear for rabbits and santa
The point was that you can train people with certain behavious

Question 13

A typical classical conditioning experiment

Answer 13

-Stage 1: Habituation – CS presented alone
• Stage 2: Acquisition – CS presented along with US
• Stage 3: Extinction – CS presented alone again
- Throughout we measure a response (UR/CR)

Question 14

A typical experiment: Habituation

Answer 14

US causes UR

Then CS does not cause CR

Question 15

A typical experiment: Acquisition

Answer 15

CS does not cause CR
US causes UR
Repeating eventually CS causes CR and US causes UR
The strength of CR increases with more trials

Question 16

A typical experiment: Extinction

Answer 16

CS causes CR but over time CS does not cause CR

Question 17

Two factors influence the acquisition curve:

Answer 17

Intensity of the US (more intense, more rapid learning)

– Order and timing (the CS coming before the US is better)

Question 18

Timing: Delay Conditioning-Short

Answer 18

There is a short interstimulus interval (ISI) of the CS before the US

Question 19

Timing: Delay Conditioning-Long

Answer 19

There is a long interstimulus interval (ISI) of the CS before the US

Question 20

Timing: Trace conditioning

Answer 20

There is a trace interval (a gap) after the CS and before the US

Question 21

Timing: Simultaneous conditioning

Answer 21

CS and the US are at the same time

Question 22

Timing: Backward Conditioning

Answer 22

US is before the CS

Question 23

Back to Delay conditioning: Is there an optimal ISI?

Answer 23

Interstimulus interval of CS before the US

Question 24

Two Types of Pavlovian Conditioning

Answer 24

• Excitatory conditioning
– CS predicts the occurrence of US
– example: if ‘A’ is a bell… A-US, A-US, A-US
• Inhibitory conditioning
– CS predicts absence of US
– example: if ‘B’ is a light… A-US, A-US, AB, A-US, AB
• here B predicts the absence of US

Question 25

Inhibitory conditioning

Answer 25

• A-US, A-US, A-US —> A leads to a CR (excitatory
conditioning)
• A-US, AB-nothing, A-US, AB-nothing –> B?
• The animal learns that B predicts the absence of US and therefore doesn’t make a CR (inhibitory conditioning)
• The problem: How do we know that animal learned something about B summation test and retardation tests
An inhibitor must pass both

Question 26

Retardation test

Answer 26

• First inhibitory conditioning takes place
– A-US, AB-nothing, A-US, AB-nothing –>
– B becomes inhibitor ‘I’
• To test it - train an inhibitor ‘I’ and a neutral stimulus ‘N’ to become excitatory
– I-US, I-US, I-US
– N-US, N-US, N-US
– Slower learning to inhibitor: I < N

Question 27

Summation test

Answer 27

First inhibitory conditioning takes place
– A-US, AB-nothing, A-US, AB-nothing –>
– B becomes inhibitor ‘I’
• To test it - Present:
– A new excitatory CS alone: ‘N’
– A new excitatory CS + the inhibitor: N+I
N+I < N
The combo should evoke a
WEAKER CR

Question 28

What happens during extinction?

Answer 28

Acquisition (CS+US) increases the strength of the CR but Extinction is when CS is presented alone
Extinction is not simply earsing whatever association was formed during acquistion

Question 29

Spontaneous recovery

Answer 29

Reintroduce the CS after a “break” and the CR appears

Question 30

Renewal

Answer 30

§ Renewal: when extinction is context specific

• Acquisition in context X
• Extinction in context Y
• Present CS in context X: CR

Question 31

Reinstatement

Answer 31

Reinstatement (reminder effect)

• present US alone after extinction
• then present CS = CR

Question 32

The hidden assumptions of classical conditioning

Answer 32

e.g.,
• Any two stimuli can be paired together (equipotentiality)
• The more two stimuli are paired, the stronger the individual will associate them (contiguity)
• Conditioning changes trial to trial in a regular way (contingency)
…. Blocking and Superconditioning show us these are wrong

Question 33

Blocking- rat example

Answer 33

Kamin (1968)
• Rats divided into ‘Blocking’	
and ‘Control’ groups.	
• In the control group:	
– rats saw both a light and	
heard a noise	and	then	got shocked	
– Repeat	until	rats	developed a CR	
• Kamin then tested whether	
the rat reacted to just the	
light by trying	to avoid	
being shocked (it did).
• In the blocking group:	
–  rats heard a noise and	
then got shocked until they	
developed a CR	
– rats then heard the noise	
and	saw	the	light and	then	
got shocked	
• Kamin then tested	
whether the rat reacted to the	light	by trying to avoid being	shocked.	
• It didn’t.
• Rats in both the blocking	and control groups had	seen	the light and then been	
shocked exactly as	
many times	
• However, the rats	 reacted differently	
• This is called the Blocking	Effect

Question 34

The blocking effect and hidden assumptions

Answer 34

Any two stimuli can be paired (equipotentiality)
The more two stimuli are paired, the stronger the individual will associate them (contiguity)

Paring the light with the shock didn’t lead to conditioning
The control group and the blocking group had the noise+light/shock pair the exact amount of times

Question 35

Superconditioning- rat example

Answer 35

• The opposite of	blocking	
• (Rescorla, 1971)	
• some rats were played a	
tone in the absence of a	
shock – tone became cue	of safety (Inhibitor)	
• Later rats were presented	
the tone with a light	 followed by a shock
• Finally rats were presented	
the light alone – rats in	this	
group showed stronger	
conditioning to the light	
than	rats in a control group

Question 36

Blocking defined

Answer 36

• Blocking - When a neutral stimulus and an excitatory stimulus together are paired
with the US
• The learner does not
form an association between the neutral stimulus and the US

Question 37

Superconditioning defined

Answer 37

Superconditioning	–	
When a neutral	
stimulus and an	
inhibitory stimulus	
together are paired	
with	the US	
• The learner forms a	
stronger association	
between	the neutral	
stimulus and the US