What was Thorndikes Law of Effect?
- “Of several responses made to the same situation, those which are accopanied or closely followed by satisfaction will, other things being equal, be more firmly connected with the situation, so that, when it recurs, it is more likely to recur.”
- Dominated for 60 years until the computer analogy
- Satisfiers (reinforcers) ‘stamp in’ S-R connections.
Describe the Clever Hans effect
- Hans taught the horse to respond by tapping a specific number of times to answer a maths problem (i.e. 2+4)
- Later found out that the horses responses were cued (unintentionally). by the rising of his head/hat.
Conclusion: must control for unintentional cueing
Describe John Watson’s philosophy and why he rejected the Law of Effect (Thorndike)
- S-R Learning theory on rats
- One of the very first behaviourists
- Emphasised that scientific study of behaviour needed to be observable
- Challenge to introspection
Watson rejected the Law of Effect because he believed that it was too subjective.
- Proposed ‘Law of frequency’ as the basis of habit formation
- Anti-mentalism: In order for behaviour to be studied it needed to be observed through public (directly observable) events, not private events (i.e. conscious experience)
Watsons famous experiment: Conditioned fear of rats into little Albert through associating two stimuli with each other (S-S learning/classical conditioning) - direct critique of freud psychoanalysis ‘childhood trauma’.
Describe Ivan Pavlov’s (1849-1936) contributions and how did Wolfsohn’s discovery go against this?
What were Pavlov’s main contributions and what were his limitations:
Pavlov discovered that dogs would eventually salivate to the sound of bells when the sound was paired repeatedly with food (physiological response). Pavlov helped:
- Term US, UR, CS, CR
- Stimulus substitution theory: type of salivation (response) depends on type of US
Pavlovs limitations:
- Outdated neurophysiology (ignore synapses)
- Monolithic theory: all learning was a result of conditioned reflexes
Wolfsohn: type of salivation depended on meat, acid, sand as US (discovery of secretin thwarted Pavlov’s theory that UR was based solely on neural reflex)
However allowed Pavlov to study the psychological process of learning through observable physiological processes
What did Clark Hull introduce and how does it relate back to Thorndike’s theory? What did Crespie (1942) introduce?
‘Mechanistic behaviourism’
- Hull believed that Watson’s behaviourism approach was too simplistic
Introduced the ‘Drive reduction theory’
Animals were motivated to act to satisfy drives according to a biological need, and to maintain homeostasis.
Cold -> shiver
Hungry -> forage
Drive theory returned to Thorndike’s law of effect as reinforcement ‘Stamps in’ S-R connection.
Crespie introduced the idea of successive negative contrast: motivation to act was dependent on size of reward.
What did Edward Tolman’s views on behaviourism?
Distinguished between learning and performance (animals could learn someting but not demonstrate it)
Tolman believed animal behaviour was goal directed, animals learn to expect reward.
Reinforcement was not necessary for learning, however its presence demonstrated learning.
Devised an experiment which proved rats acquire a cognitive map (despite a reward)
Conditioning is just one form of learning (not the only one)
What were some of the problems with the Hull-spence S-R theory?
Learning occurs without reinforcement
A. Latent learning: tolman’s rats, distinction between learning and performance
B. Sensory preconditioning
Light -> Noise
Noise -> Shock
Light = fear response (guilt by association)
- Successive contrast effects
Tinklepaugh: the monkey, banana and lettuce leaf (indicates expectancies)
Crespie showed that motivation to respond lower if the reward was decreased. - Reinforcement without drive reduction
Harlow’s studies of learning in rehsus monkeys (e.g., learning sets) showed that monkeys would learn to solve problems without extrinsic rewards - Partial reinforcement and extinction
Frustration theory - Avoidance learning
1934 O.Hobart Mowrer arrives at Yale; how to prevent bed-wetting? The bell-and-pad method for curing enuresis; Pavlovian conditioning?
Guinea pigs ran more if running prevented a shock
Mowrer (1947): two factor theory
Fear of the warning signal: Pavlovian learning
Termination of fear: Instrumental learning
Hull believed in a single form of learning:
S-R learning
Mowrer: In order to explain avoidance learning, 2 factors were needed
What did Skinner propose?
Skinners radical behaviourism believe learning theories aren’t necessary
Skinner believed that facts, not theories are necessary for science
Skinner’s research programme:
- Developed the skinner box
- Behaviour of Organisms (1938) showed that most Pavlovian phenomena were also found with operant (instrumental) conditioning
- Founder of the ideas in ABA therapy
Describe the cognitive revoution in American psychology:
Rejection of S-R theory (Hull et al) and behaviourism in general, including Skinner
Skinner’s Verbal behaviour (1957) book
Chomsky (1959) critique of Verbal Behavior
- Psycholinguistics emerges
- Studies of thinking along non-Hullian lines
- Artificial intelligence and computer nodels of human mental processes (neural networks)
- Brewer’s (1974) review: ‘There is no convincing evidence for operant and classical condtioning in human beings’
Animal learning: Revolt against S-R theory and against operatn conditioning
Development of 2-factor theory of avoidance and conditioned supression
Describe Kamin’s blocking effect and what associative learning theory was this linked to?
CS1 (light) -> food (US) = CR (salivation)
CS1 (light) & CS2 (noise) -> food (US) = CR
However, CS2 (noise) has been blocked due to previous learning about CS1
CS2 (noise) alone does not trigger CR
Blocking was a very general effect linked to the Rescorla Wagner theory
The Rescorla Wagner theory described how conditioning was the result of competing predictos. The best predictors win the prize (conditioning).
