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Learning
pp. 194-233
• Non-associative learning
– Sensitization
– Habituation
– Dishabituation
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Classical conditioning
Operant conditioning
Latent learning
Cognitive maps
Insight learning
Observational learning
Nature Vs. Nurture
• “Give me a dozen healthy infants, well-formed, and my own specified world to bring
them up in and I'll guarantee to take any one at random and train him to become any
type of specialist I might select – doctor, lawyer, artist, merchant-chief and, yes, even
beggar-man and thief, regardless of his talents, penchants, tendencies, abilities,
vocations, and race of his ancestors. I am going beyond my facts and I admit it, but so
have the advocates of the contrary and they have been doing it for many thousands of
years.” John Watson (1930)
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What is learning?
• Modification through experience of pre-existing behavior and understanding
• This is shared with all species!
• We learn all the time whether we want it or not
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Why is it important?
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You need to adapt to a constantly changing environment to survive
Avoid making the same mistakes
Master skills
Predict events
Learning About Stimuli
• Sensitization
• Habituation
• Dishabituation
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How Habituation Works?
• Opponent process theory:
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Stimuli that arouse strong emotions
These emotions disrupt state of equilibrium
Disruption triggers an opponent process to counteract disruption
Repeated arousing makes opponent process stronger
Equilibrium restored
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Classical Conditioning
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• Associative learning
• Pairing two stimuli together
• Learning stimulus-response associations
Phase 1
Phase 2
Phase 3
The office clip
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• http://www.youtube.com/watch?v=qzXOscWD-Sg
Classical Conditioning is…
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• A neutral stimulus (bell) paired with a reflex triggering stimulus (meat
triggers salivation)
• The neutral stimulus (bell) triggers the reflex alone (salivation), without the
reflex triggering stimulus (meat)
For Classical Conditioning You Need…
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• Unconditioned Stimulus (UCS)
– Triggers a reflex response naturally
• Unconditioned Response (UCR)
– The reflex triggered by the UCS
• Conditioned Stimulus (CS)
– The originally neutral stimulus (does NOT triggers a response naturally), eventually associated
with the UCS
• Conditioned Response (CR)
– The reflex triggered by the UCS now responding to the CS
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Extinction and Spontaneous Recovery
Write in a Paper
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• Which is the UCS, CS, CR, UCR in The Office clip?
Second-order Conditioning
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• Conditioned stimulus (CS) acts like an Unconditioned stimulus (UCS)
• Drug Addiction
Generalization and Discrimination
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• Generalization:
– Similar stimuli to the CS also elicit the CR
– The greater the similarity the stronger the response
• Discrimination:
– Learn to differentiate among similar stimuli to generate different responses
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• Little Albert Video
Factors Affecting Learning
Other Factors…
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• Predictability:
– Does the CS always predict the UCS and only the UCS?
• Signal Strength:
– CR is greater with a strong UCS
• Attention:
– You have to pay attention to the appropriate stimulus
Biopreparedness
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• Certain events are specially suited to form associations with other events
• Conditioned Taste Aversion
– Does not follow the exact same rules than the classical conditioning
Some Applications..
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• Systematic Desensitization
• Predator Control
• Alzheimer’s Disease Prediction
Instrumental Conditioning
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• Thorndike’s Puzzle box:
– Learn relationships between behavior and its consequences
– Law of effect
– If a response in presence of a stimulus produces rewards it increases its likelihood the next time
the same stimulus is presented
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Operant Conditioning
• What is operant conditioning?
• Components of operant conditioning
– Reinforcement
– Punishment
• Primary and secondary reinforcers
• Shaping
• Schedules of reinforcement
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Operant Conditioning
• Learning to respond to the environment to produce good consequences and avoid bad
ones
• Do something to the environment (operant)
• What is the difference with classical conditioning?
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Operant Conditioning
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• Skinner’s box
– Thorndike measures whether the animal made the response or not
– Skinner measures the number of behavior’s in a given period of time
– Allowed a more precise control of the stimuli presented
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Components of Operant Conditioning
Components of Operant Conditioning
• Reinforcer:
– Stimulus that increases probability of behavior
• Punishment:
– Stimulus that decreases the probability of behavior
• Positive:
– Add a stimulus as a consequence of a response
• Negative:
– Remove a stimulus as a consequence of a response
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Components of Operant Conditioning
Components of Operant Conditioning
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Positive Reinforcement
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• Give
– Candy
– Money
– Golden stars
• Can you think of other examples?
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Components of Operant Conditioning
Components of Operant Conditioning
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Negative Reinforcement
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• Remove
– Electric shock
– Loud noise
– Awkward silence
• Can you think of other examples?
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Components of Operant Conditioning
Components of Operant Conditioning
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Positive Punishment
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• Give
– Slap
– Bad grade
– Scream
• Can you think of other examples?
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Components of Operant Conditioning
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Components of Operant Conditioning
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Negative Punishment
• Remove:
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Freedom
TV
Car
Money
• Can you think of other examples?
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Types of Operant Conditioning
Types of Operant Conditioning
Types of Operant Conditioning
Types of Operant Conditioning
Types of Operant Conditioning
Types of Operant Conditioning
Operant Conditioning
• Can you interpret The Office clip in terms of operant conditioning?
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Primary And Secondary Reinforcers
• Primary Reinforcer:
– Innately rewarding
• Secondary Reinforcer
– Previously neutral reinforcer now associated with a primary reinforcer
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How Do You Teach Complex Behaviors?
• Shaping:
– Reinforcing successive approximations to desired behavior
• How can you teach a sheep to do a full turn?
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Schedules Of Reinforcement
• Continuous reinforcement
– Reinforced every time
• Partial reinforcement
– Only reinforced sometimes
• Why would you reinforce only sometimes?
• What about extinction and predictability?
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Partial Reinforcement
• Fixed Ratio:
– Reward after a fixed number of responses
– FR6 = reward after 6th response
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• Variable Ratio:
– Reward after a variable number of responses
– VE6 = reward after an average of 6 responses
Partial Reinforcement
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• Fixed Interval:
– Reward after the first response after a fixed period of time
– FI15 = Reward after first response after 15 seconds
• Variable Interval:
– Reward after the first response after a variable period of time
– VI15 = Reward after first response after a period of 15 seconds in average
Make Groups of 5!
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• Come up with examples of FR, VR, FI, VI but with negative reinforcement,
positive punishment and negative punishment.
Why Reinforcers Work?
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• Premack Principle
– Preferred activity reinforces any less preferred activity
– Play videogames if you do your homework
• Disequilibrium Hypothesis
– Any activity can become a reinforcer if it has been witheld for a while
• Biological Approach
– “Pleasure centers” in the brain
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Are Punishments Useful?
• Advantages
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• Disadvantages
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Signaling wrong behaviors
Works when it is contingent to the wrong behavior
It is useful when used in combination with other techniques
Works if you tell what was wrong and what is a good alternative behavior
Does not erase an undesirable habit
Is maintained when it is possible to avoid detection
Association between punishment and punisher
Physical punishment can become aggression and children may imitate it
Does not tell how to improve
Some Applications…
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Animal training
Cultural accepted norms
Improving productivity in the work environment
Therapeutic techniques
Stimulus control therapy
– Helps people sleep
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Other Ways Of Learning?
• Learned Helplessness
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• Latent Learning
– Tolman’s Experiment
• Cognitive Maps
• Insight Learning
• Observational Learning
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Learned Helplessness
• You can learn expectations about the loss of control of the environment
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Latent Learning
• Do you know the lyrics of your favorite song?
• What’s on TV on Tuesday nights?
• What are some movies in theatres right now?
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Cognitive Maps
• Can you imagine going from the classroom to the REP PS-2 waiting room?
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Insight Learning
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Sudden understanding about how to solve problem
First performance usually without error
Solution remembered well
Principle underlying solution is easily applied to others
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Insight Learning
Insight Learning
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Requirements For Observational Learning
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Attention
Retention
Ability to reproduce behavior
Motivation
Characteristics of the model
TV and Violence?
• Critical Thinking
• Make two teams
• One defends TV the other attacks TV
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Learning in the Classroom
• Cultural differences
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• Active learning
• Skill learning
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Learning in Neural Networks
• Distributed knowledge
• There is no “grandma neuron”
• Neurons that fire together wire together!
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Examples of Reinforcement Schedules
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