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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

• 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– 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 stronger response.

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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

• 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

• 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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ThorndikeThe Law of Effect

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Skinner and Operant Learning

• Voluntary and goal directed

• Controlled by its consequences

• Strengthened if rewarded or weakened if punished

Skinner defined operant learning as:

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

• 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

• 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

• Dangers of using punishment– 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

• Contiuous reinforcement

• Partial reinforcement

• Fixed interval

• Variable interval

• Fixed ratio

• Variable ratio

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Reinforcement Schedules

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Reinforcement

• 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– Learned association

between US and CS

– Organism is passive

– Responses elicited

Operant conditioning– 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

• 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