Learning
• Not learning intellectually but learning behaviors– Remember psychology:
• study of behavior and mental processes
• 3 Ways we acquire behavior– Classical Conditioning (CC) – Pavlov and Watson– Operant Conditioning (OC) - Skinner– Observational Learning – Bandura
– Behaviorists – focus on observable, measurable behavior – very objective
• Height of influence in 1920s• NURTURE - environment
CLASSICAL CONDITIONING
Classical Conditioning
• Turn of the 20th century, Russian Psychologist, Ivan Pavlov discovered CC while studying digestion in dogs
• Classical Conditioning = learning by association - people and animals learn to associate neutral stimuli w/ stimuli that produce reflexive, involuntary responses and will learn to respond similarly to the new stimulus as they did the natural one
CC
• 1. US (unconditioned stimulus)– Original stimulus that elicits natural response
• (ex. Food)• 2. UR (unconditioned response)
– The natural response • (ex. Salivation)
• 3. CS (Conditioned stimulus)– Neutral stimulus paired with US that eventually elicits response
alone • (ex. Bell)
• 4. CR (Conditioned Response)– UCR solicited by CS
• (ex. Salivation)
• Learning has taken place once the animals respond to the CS without the US = Acquisition because animals have acquired a new behavior – CS produces CR without US
Pavlov’s Dogs
Factors that affect acquisition
• 1. Repeated pairings of CS & US ; more times paired = stronger CR
• 2. Order and timing of CS & US affect the strength of conditioning– Most effective = present CS first and then introduce the US
while CS is still evident . . . Called delayed conditioning
(ex. Bell rung, while still ringing food is presented)
A break of time in between CS and US weakens the response• 3. Less effective methods . . .
– a. trace conditioning• Present CS, short break, present US
– b. simultaneous conditioning• CS & US at same time
– c. backward conditioning – worst kind – doesn’t work• US followed by CS
CC – Important Terms
• Acquisition – behavior is learned. CS produces CR without US
• Extinction – behavior is unlearned. CS no longer produces CR
• Spontaneous Recovery – acquisition, extinction and period of no training. CS briefly produces CR but response is weak and will disappear quickly unless repeated training/pairing.
CC – Important Terms
• Generalization – organism responds to stimuli similar to CS. i.e. a buzzer produces the CR
• Discrimination – the organism is trained to ONLY respond to the CS. Bell, food….buzzer, no food.
• Second/Higher Order Conditioning – once CS produces CR. It’s possible to use CS as a US to condition a new stimulus
CC – John Watson
• Baby Albert Experiment – conditioned fear (many phobias are the result of CC)
– US – loud noise– UR – fear/cry– CS – white rat– CR – fear/cry
http://www.learner.org/series/discoveringpsychology/08/e08expand.html
Aversive Conditioning
• Any time in CC that the response is undesirable– Garcia affect – taste aversion
– Can be used to get you to stop an unhealthy behavior (nail biting, shock therapy)
Biology and CC
• Can animals be conditioned to do any response?– Equipotentiality – many behaviorists believed
yes. All organisms have equal potential.– Instinctive Drift – research says
equipotentiality is false. Animals will drift towards their natural instincts and cannot be conditioned to do things that go against their nature.
http://www.youtube.com/watch?v=WfZfMIHwSkU“The Office” CC clip
OPERANT CONDITIONING
Operant Conditioning
• Learning by association – associate a behavior with its consequences
• Edward Thorndike – predecessor– Law of effect – if consequences of a behavior are
pleasant, the stimulus response connection is strengthened and the behavior increases. If consequence is unpleasant, the connection will weaken and behavior will decrease. Thorndike called this instrumental learning – the consequence is instrumental to you learning the behavior
Father of Operant Conditioning…. BF Skinner
Skinner
• Skinner created the Skinner box with pigeons
• Reinforcer = food; reinforcers are always positive consequences
• Punishment is always a negative consequence
• + addition, - subtraction
Reinforcements – makes behavior more likely
• + reinforcement: the addition of a desirable consequence; Johnny gets all As and his parents give him $100
• - reinforcement: the subtraction of something unpleasant as a desirable consequence; Johnny gets all As and his parents say he doesn’t have to do his chores.
Punishments make behavior less likely
• Punishment: the addition of an unpleasant result; Johnny gets an F and gets a spanking or extra chores
• Omission Training: the removal of a pleasant stimulus; Johnny gets an F and loses his car privileges
OC Terms
• Escape Learning – terminating an aversive stimulus. Johnny comes to class and hears there is an exam and he asks to go to the clinic (- reinforcement)
• Avoidance Learning – enables one to avoid unpleasant stimulus all together. Johnny remembers there is a test and he skips school. (- reinforcement)
OC Terms
• Shaping – reinforcing gradual steps of improvement as one gets closer to desired behavior.
• Chaining – reinforcement after subject performs a series of behaviors. Little Johnny cleans his room, brushes his teeth, says his prayers and then gets a bed time story
• Premack Principle – what works as a reinforcer for one person may not work for another. If I don’t like chocolate, than a candy bar will not work as a reinforcer for me
OC Terms
• Acquisition – behavior learned. Rat presses lever to get food
• Extinction – behavior is unlearned. Rat no longer gets good and therefore stops pressing lever
• Generalization – do similar behavior to get reinforcer – rat presses other button hoping for food
• Discrimination – only get reinforcer for specific behavior
Types of Reinforcers
• Primary – innately rewarding – food, water, rest
• Secondary – things we learn to value – praise, games, material objects
• Generalized Reinforcer – can be traded in for something else – money– Token Economy – desired behavior gets
tickets or tokens to be traded for reinforcers (arcade)
Reinforcement Schedules
2 critical questions
• 1.) Do I know EXACTLY when the reinforcer is coming? – Yes = fixed– No = variable
2.) Is the reinforcer contingent on me completing a task?
- Yes = Ration
- No = Interval
4 Schedules
• Fixed Ratio (FR) – I get a water break after running 5 suicides
• Variable Ratio (VR) – I’m going to play the slot machine and hope I win
• Fixed Interval (FI) – spring break is 4 weeks away
• Variable Interval (VI) – my car is in the shop and I am not sure when it will be ready
Variable schedules are more resistant to extinction that fixed schedules. Once an animal becomes accustomed to a fixed schedule, a break in the pattern will quickly lead to extinction
• When learning a behavior, continuous reinforcement is best. Once behavior learned, variable reinforcement is better.
• VR most resistant to extinction – why gambling is addictive
Observational Learning
Social Modeling
Albert Bandura’s Bobo Doll Experiment
Observational Learning
• Modeling has two basic components – – Observation– Imitation– Kids who observed models play violently with
the Bobo doll were more likely to interact violently with the Bobo doll themselves
– We can model prosocial or antisocial behaviors– Do violent TV shows and video games make
people more likely to act in violent ways???
http://www.youtube.com/watch?v=jWsxfoJEwQQBobo Doll footage
Other Types of learning
• Latent Learning – Edward Tolman – hidden learning Ex: rats and maze – they don’t show knowledge until there is an incentive
• Insight Learning – Wolfgang Kohler – when one suddenly realizes how to solve a problem. The answer comes in a flash or insight. Ex: apes and bananas