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Learning
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Thoughts on Learning
“Learning is not compulsory. Neither is
survival.”
– W. Edwards Demming
“Education is what survives when what has been
learned has been forgotten.”
– B.F. Skinner
“I am always doing that which I cannot do, in
order that I may learn how to do it.”
– Pablo Picasso
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What is Learning?
A relatively permanent change in behavior
that results from experience
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Types of Learning
• Classical conditioning
• Operant conditioning
• Cognitive and social learning
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Classical Conditioning:
Examples
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Sound of a dentist’s drill: sweaty palms
Smell of mom’s perfume: smiling
Sight of certain restaurant: nausea
Noise of a can opener: cat comes running
Smell of a hospital: weakened immunity
How does this happen?
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Classical Conditioning
• Discovered (accidentally) by Ivan Pavlov
• Components
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Unconditioned Stimulus (US)
Unconditioned Response (UR)
Conditioned Stimulus (CS)
Conditioned Response (CR)
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Pavlov’s Observation
• Studied digestion in dogs
• Presented meat powder
and measured salivation
• Dogs started salivating
before food was presented
• Why?
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Pavlov’s Experiment: Phase 1
• Food (US): salivation (UR)
– Reflexive response
• Tone (CS): nothing (CR)
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Pavlov’s Experiment: Phase 2
• CS is repeatedly paired with the US
– A tone is sounded before the food is presented
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Pavlov’s Experiment: Phase 3
• Eventually, the CS elicits a new CR
– Hearing the tone by itself causes salivation
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Classical Conditioning:
Conditioned Emotional Response
• Avoidance learning
• Conditioned phobias
– Little Albert
• Biological preparedness
• Contrapreparedness
– Easy to develop a snake phobia
– Hard to develop a car door phobia
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Classical Conditioning
• Extinction
• Spontaneous recovery
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Classical Conditioning
• Stimulus generalization
• Stimulus discrimination
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Classical Conditioning
Stimulus generalization is the extension of a
conditioned response from the training
stimulus to similar stimuli.
• Through conditioning Baby Hannah smiles and
laughs at the title screen with dark background
and white writing that precedes a funny song and
cartoon on her “Merrytubbies” video tape. Her
parents notice that she also smiles and giggles at
the FBI Warning screen appearing on movie
videotapes.
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Stimulus generalization is the process of extending a learned response to new
stimuli that resemble the one used in training. Similar stimuli similar elicit a
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stronger response.
Classical Conditioning
• Discrimination is the process of learning to
respond differently to two stimuli because
they produce two different outcomes.
– Gradually Hannah stops laughing at the FBI
Warning screen because the song and cartoon
do not follow it.
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Higher Order Conditioning
• Pair CS1 with a new CS2
• CS2: CR
• But, CR will be weaker
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The General Rule of Conditioning
• Previously neutral stimulus will lead to a conditioned
response (CR) whenever it provides the organism with
information about the upcoming occurrence of the
unconditioned stimulus (UCS). (Rescorla, 1992;
Rescorla & Wagner, 1972).
• As with Pavlov’s dogs, the sound of the metronome just
before presentation of food (UCS) became a
conditioned stimulus (CS) because the dogs began
salivating (CR) when the metronome ticked.
• Conditioning occurs because the sound of the
metronome provides the dog with information that
food will soon be delivered.
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Classical Conditioning Applied
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Drug overdoses
Smoking: environmental cues
Systematic desensitization
Advertising: sex appeal
Taste aversion
Conditioning and the immune system
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Types of Learning
• Classical Conditioning
• Operant Conditioning
• Cognitive and Social Learning
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Operant Conditioning
• Classical conditioning teaches about future events,
but it seldom allows one to change those events.
• Thorndike proposed that behavior became more
or less likely based on whether it produced a
desired or undesired consequence, something he
called the “law of effect”.
• B.F. Skinner later called this idea “operant
conditioning” because an organism’s behavior is
operating on the environment to achieve some
desired goal.
• This is a more active form of learning than that of
classical conditioning.
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Operant Conditioning: Examples
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Tantrums are punished: fewer tantrums
Tantrums bring attention: more tantrums
Slot machine pays out: gamble more
Reward dog for sitting: dog is likely to
sit
How does this happen?
Fuzzy Knows!!
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Operant Conditioning
• Thorndike’s puzzle box
– Law of Effect: actions that have positive
outcomes are likely repeated
• Skinner box
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Thorndike
The Law of Effect
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Skinner and Operant Learning
Skinner defined
operant learning
as:
• Voluntary and goal
directed
• Controlled by its
consequences
• Strengthened if
rewarded or
weakened if punished
The mouse is “operating” on its environment by
pressing the food lever in the Skinner box and
receiving a food reward.
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Operant Conditioning: Principles
• Stimulus-Response
• Reinforcement
– Positive reinforcement
– Negative reinforcement
• Punishment
– Positive punishment
– Negative punishment
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Principles of operant conditioning
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Relies on principle of reinforcement, in which the
consequences of a behavior lead to a higher frequency
of the behavior occurring later on.
Reinforcement works best when it involves a response
contingency.
There are different types of reinforcers:
Positive reinforcement is when a desired reinforcer is
presented after the occurrence of the desired behavior.
Negative reinforcement is when an unpleasant event or
circumstance is removed after the occurrence of the
desired behavior.
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Principles of operant conditioning
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Punishment is typically the occurrence of an
unpleasant event as a consequence of a response,
always decreasing the likelihood of the recurrence of
that response.
– Punishment is most effective if it has three
characteristics:
• It should occur immediately after the undesired
behavior.
• It must be consistent.
• It must be aversive without being abusive
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Effective Punishment
• Should be
– Swift
– Consistent
– Appropriately aversive
• Challenges
– Physical punishment may be imitated
– May fear the person who punishes
• Most effective when paired with reinforcers
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Principles of operant conditioning
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Dangers of using punishment
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It does not eliminate the capacity to engage in the
problem behavior.
Physical punishment may elicit increased aggressive
behavior in the person being punished.
Through classical conditioning, the person being
punished may learn to fear the punisher.
Typically requires continuous observation.
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Shaping Behavior
Shaping, or the method of successive
approximations, is the process of teaching a new
behavior by reinforcing closer and closer
approximations to the desired behavior.
Behavior is shaped by breaking down a desired
behavior into smaller substeps (or
approximations) then successively reinforcing
each substep until the desired behavior is
reached.
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Building Complex Behaviors
• Shaping
– Gradual reinforcement of successive
approximations of target behavior
– Used to train animals to do complex tricks
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Reinforcement
• Reinforcement increases the probability of the
behavior it follows.
• Continuous reinforcement (rewarding every correct
response) results in fast learning, but can be quickly
extinguished.
• Partial reinforcement keeps us responding vigorously
for longer.
• Variable ratio reinforcement leads to the highest rates
of responding greatest resistance to extinction.
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Reinforcement Schedules
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Contiuous reinforcement
Partial reinforcement
Fixed interval
Variable interval
Fixed ratio
Variable ratio
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Reinforcement Schedules
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Reinforcement
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Primary reinforcers
Secondary reinforcers
Behavior modification
Immediate versus delayed reinforcement
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Beyond Basic Reinforcement
• Generalization
• Discrimination
– Discriminative stimulus
• Extinction
• Spontaneous recovery
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Classical versus Operant
Conditioning
Classical conditioning
Operant conditioning
– Learned association
between US and CS
– Organism is passive
– Responses elicited
– Associate response
and reinforcement
– Organism is active
– Responses emitted
Shared features
– Avoidance learning
– Extinction and spontaneous recovery
– Generalization and discrimination
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Types of Learning
• Classical conditioning
• Operant conditioning
• Cognitive and social learning
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Cognitive Learning
• Latent learning
– Tolman’s rats: cognitive maps
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Cognitive Learning
• Insight learning
– “Aha” experience
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Observational Learning
• Imitation or Modeling
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Observational Learning
Observational learning is learning a behavior by
observing or imitating the behavior of others
(models). Behavior that has been rewarded is most
likely to be imitated.
During observational learning, one learns by
watching how others behavior is reinforced or
punished, not one’s own behavior.
Operant learning, on the other hand, is learning
directly from one’s own experience.
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Bandura’s Social Learning Theory
People learn social behaviors mainly through
observation and cognitive processing of information,
rather than through direct experience. Observational
learning is the central tenet to this theory.
For observational learning to occur, one must
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Pay attention to a model’s behavior
Remember what has been observed
Be able to perform the observed behavior
Be motivated to perform the observed behavior
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Aggressive Behavior
• Studies suggest that children learn
aggressive behaviors through observation.
• Punishment does not seem to prevent the
learning of aggression, but it does seem to
inhibit its expression.
• Nonaggressive responding can also be
learned through positive social modeling.
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Observational Learning
• Bandura’s Bobo doll study
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