History and background to learning
A brief history of learning
Definition of Learning
Paradigms of Learning
Ivan Pavlov's Experiments
Features of Classical Conditioning
Application to Humans: Psychotherapy & Advertising
Limitations: Garcia's experiments
Thorndike's & Skinner's Experiments
Schedules of Reinforcement
Positive & Negative Reinforcement, Punishment
Application to Humans i) Shaping children,
"Token economy", Psychotherapy, Utopias
Bandura's "Bobo doll" Experiment
Application: Role of Modelling, T.V. violence
A Brief History of Learning
Arising from the Darwinian view that organisms acquire new traits, early behaviourists took a "functionalist" approach. Here there was an emphasis on the nature of mind and thinking across animal species where notions of the animal mind or consciousness were considered.
Soon afterwards, in part due to the failure of others to examine their own consciousness through introspection, the interest in action and behaviour came into vogue.
Over a relatively short period of time psychologists went from studying behaviour as a reflection of consciousness, to behaviour as a substitute for consciousness.
In 1913 John B. Watson has established the behaviourist perspective which sought to eliminate consciousness and the mind from psychology and focus on learning only.
Major paradigms of learning:
Classical Conditioning: stimulus substitution
Ivan Pavlov (1849-1936)- physiologist studying the salivation response- first Russian to get a Nobel prize 1904
Accidentally discovery conditioning as a nuisance when assistant's footstep would lead to saliva before food was placed in dog's mouth. Called it "psychic reflex" as it was not purely a physiological response
UCS: Meat powder - - -> UCR: Saliva
UCS: Natural stimulus to which natural "reflex" response (UCR)
CS: Footsteps - - - - - - - -> CR: saliva
CS: Neutral stimulus (normally dogs don't salivate to footsteps (CR)
Take a "hardwired" reflex and associate it with a "neutral" stimulus, later the neutral stimulus gives response.
e.g. In a car accident at a
particular location, next afraid to drive at that location because of fear
associated with cues.
e.g., Watson's Little Albert ; 8 months- loud noise when play with a white rat- feared all furry objects- white beards- including Santa
e.g. Sexual fetishes can be created. e.g., - with partner-> sexual arousal, partner wearing boots- now boots lead to sexual arousal. (also favourite songs, perfumes, shampoo). george costanza
to food: (often need only one trial)
Spaghetti dinner - drink too much, now can't eat spaghetti :(
Applications of Classical Conditioning
Chocolate before Chemotherapy Candy elicits aversion!
- patients advised to avoid food before chemo
- also the smell, hospital setting evokes nausea-
Maya the mutt and going to the vet
Implication: Innate responses can be brought under environmental control
government had mega research fund for Pavlov and others
- Their goal-->control of the human beings ---> A Clockwork Orange
John Garcia: sheep ranchers in US kill Coyotes - tried in the lab- 1 or 2 exposure to mutton tainted with lithium chloride (illness inducing chemical). Found the coyotes avoided mutton altogether- ran away and vomitted!- then field tested- scattered the fence with tainted mutton- never came back!
But limitations: certain natural behaviours- rats can be CC to drinking water (taste) when make them ill but not to brightness- survival adaptive value- Except for Kai
The conditioning factors of drugs: tolerance & addictions
Special features of Classical Conditioning
period of time during which the pairing of the two stimuli occurs.
- best for 1/2 second gap from onset of Cs > UCS
Various time relationships:
Short-delayed: Bell starts then food: end together (best)
Trace: Bell goes on, ends, then food
Simultaneous: Bell and Food goes on and off together
Backward: Food first, then Bell: (worst)
Extinction: repeatedly provide CS (bell), but no food-gradually the effect lessens until no longer responds. Implication: unlearn what is no longer useful .