basic principles of learning
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Basic Principles of Learning. Basic Principles of Learning. Definition of Learning. Relative permanent change in behavior brought about through experience or interactions with the environment Not all changes result from learning Change in behavior not always immediate - PowerPoint PPT PresentationTRANSCRIPT
Basic Principles of Learning
Definition of Learning
• Relative permanent change in behavior brought about through experience or interactions with the environment– Not all changes result from learning
– Change in behavior not always immediate
• Years of isolating and studying behavior produced different principles of learning
Basic Principles of Learning
Classical Conditioning: Learning by Association
• Ivan Pavlov in Russia– Nobel Prize for saliva in digestion– Reflexive response controlled by arbitrary
stimulus (salivation when attendant approached)
• Association - key element – First recognized by Aristotle– Pavlov: classical conditioning was form of
learning through association
Basic Principles of Learning
Container of meat powder
Observation screen
Revolving drum for recording responses
Device to count drops of saliva
Tube for collection of saliva
Pavlov’s Experiment
Test of conditioning: after classical conditioning, the neutral stimulus becomes a conditioned stimulus (CS) that elicits the conditioned response (CR) of salivation
Neutral stimulus (metronome)
CS (metronome)
Conditioning procedure: during the classical conditioning procedure, the neutral stimulus is presented in association with the unconditioned stimulus (UCS) to elicit the unconditioned response (UCR)
UCR (salivation)UCR
(meat powder)
CR (salivation)
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Pavlov’s Experiments
• Systematic, effective, precise studies
• Association of two stimuli
• The more frequently the metronome and food are associated, the more often the metronome will elicit salivation
• Timing of association is highly important– Longer time intervals were less effective;
almost no learning occurred
Basic Principles of Learning
Number of drops of
saliva elicited by
metronome alone
Number of times metronome and meat powder were presented together
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Pavlov’s Studies: the more often the metronome was associated in time with meat powder, the more effective in eliciting saliva
Pavlov’s Experiment
CR (salivation)
UCR (meat powder)
Before classical conditioning: initially, the metronome is a neutral stimulus that does not elicit the response of salivation
But the unconditioned stimulus (UCS) can elicit the unconditioned response (UCR)
UCR (salivation)
Neutral stimulus (metronome)
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A
Terminology of Classical Conditioning
• Unconditioned stimulus (UCS) – Elicits response without learning
• Unconditioned response (UCR)– Unlearned, inborn response
• Conditioned stimulus (CS)– Acquires ability to elicit after paired
association with unconditioned stimulus
• Conditioned response (CR)– Elicited by conditioned stimulus
Basic Principles of Learning
CS
UCS
(meat powder)
(metronome)
CRUCR (Salivation)
Application of Terminology to Pavlov’s Experiment
Definition of Classical Conditioning
• Form of learning in which– CS followed by UCS elicits UCR
– Pairing of CS and UCS allows CS to elicit CR almost identical or similar to UCR
• Considered learning because– New behavior acquired
– Old behavior elicited by new stimulus
– Does not depend on behavior of individual
Basic Principles of Learning
Importance of Classical Conditioning
• Watson and Rayner – Made classical conditioning famous with
Little Albert experiments• Learned to fear rats - unethical today
• Watson and Jones– Counterconditioning: reversing the CR
• Useful in – Explaining aspects of human health– Explaining sexual fetishes and arousals
Basic Principles of Learning
Watson and Raynor Study
CS
UCS
(rat)
(loud noise)
CRUCR
(fear)
Operant Conditioning: Learning from the Consequences of Your Behavior
• Form of learning – Consequences of behavior lead to change based
on probability of consequences occurring
• Thorndike and the puzzle box – Researching animal intelligence
– Law of effect: consequences determine response occurring in future
Basic Principles of Learning
Operant Conditioning
• Three types of desirable and undesirable consequences that influence behavior
– Positive reinforcement
– Negative reinforcement
– Punishment
Basic Principles of Learning
Reinforcement
• Positive reinforcers – learned and inborn
• Primary reinforcement – Innately reinforcing – Examples: food, water, warmth, physical activity
• Secondary reinforcement– Learned through classical conditioning– Examples: rewards, money, praise
Basic Principles of Learning
Primary reinforcer
Secondary reinforcer
Schedules of Positive Reinforcement
• Continuous – reinforcer for every response
• Schedules – Fixed ratio – reinforcer given after each
specified or fixed number of responses
– Variable ratio – reinforcement after varying number of responses
Basic Principles of Learning
Fixed Ratio Variable Ratio
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Patterns of Behavior Produced by Reinforcement
Schedules of Positive Reinforcement
• Schedules– Fixed interval schedule – reinforcement
based on time (ie: every 2 hours)
– Variable interval schedule – reinforcement after variable amount of time (ie: reinforced after 1 hour, then after 4 minutes, then after 35 minutes like slot machine gambling)
Basic Principles of Learning
TimeTime
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Fixed Interval Variable Interval
Patterns of Behavior Produced by Reinforcement
Shaping
• Reinforcing steps toward targeted behavior or method of successive approximations
• Skinner – Skinner box– Rat pushes lever to get food after
• Rewarded for steps of nearing, touching, and pushing on lever
• Used for children and those with developmental handicaps
Basic Principles of Learning
Operant Conditioning
Electric gridFood cup
Dispenser tube
Pellet dispenser
Lever
Signal lights
Speaker
To shock generator
Negative Reinforcement
• Something unpleasant, aversive, undesired is removed by behavior or does not happen at all– Not the same as punishment– Not a bad habit being reinforced– Very powerful method of reinforcement
• Escape conditioning – negative event stops
• Avoidance conditioning – negative event avoided
Basic Principles of Learning
Punishment
• Consequence of behavior is negative– Behavior has been punished
– Behavior frequency will decrease
– When appropriately used – ethical and valuable tool for discouraging undesired behavior
• Physical punishment used by society, parents, and others – has dangers– Raises ethical questions
Basic Principles of Learning
Dangers of Punishment
• Often reinforcing to the punisher
• Often has generalizing effect on the individual
• May lead to a worse problem (learning to dislike punisher, reacting aggressively towards others)
• Criticism trap – belief that punishment is ineffective leads to using criticism (criticism sometimes reinforces negative behavior)
• Punishment may suppress behavior temporarily but is not long term solution
Basic Principles of Learning
Guideline for Use of Punishment
• Do not use physical punishment
• Punish inappropriate behavior immediately
• Positively reinforce appropriate behavior
• Clarify what behavior is being punished and why (separate the person from the behavior)
• Do not mix punishment with rewards
• Do not back down once you begin to punish
Basic Principles of Learning
Basic Principles of Learning
Contrasting Classical and Operant Conditioning
Classical conditioning involves– Association between
two stimuli– Reflexive, involuntary
behaviors– UCS making behavior
happen
Operant conditioning involves– Association between
response and consequence
– More complicated voluntary behaviors
– Reinforcing consequence occurring only if desired response is given
Basic Principles of Learning
Stimulus Discrimination and Generalization
• Stimulus discrimination – deciding between appropriate and inappropriate occasions for a response– Learned by humans and animals
• Stimulus generalization – opposite of stimulus discrimination– Similarity of two or more stimuli
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Wavelength
Stimulus Generalization and Reinforcement of a Pigeon’s Pecking
Basic Principles of Learning
Extinction: Learning When to Quit
• Extinction – learned response stops occurring because
original source of learning was removed
• Classical conditioning– Fear is very difficult to extinguish– CR extinguished if CS is repeatedly presented
but UCS is no longer paired with it
• Operant conditioning– Extinction results from change in consequence
Basic Principles of Learning
Extinction
• Differences between classical conditioning and operant conditioning
• Operant conditioning– Early stage extinction leads to frustration
– Partial reinforcement effect: schedule and type of reinforcement greatly influence extinction
• Fastest extinction - continuous reinforcement
– Response prevention: extinguishes avoidance responses quickly
Basic Principles of Learning
Spontaneous Recovery and Disinhibition
• Course of extinction not smooth – learned response occurs often before extinction
• Spontaneous recovery– Response reappears during extinction
• Disinhibition– Presentation of intense, unrelated stimulus can
cause strength of response to return– Pavlov: no response is unlearned, just inhibited
Basic Principles of Learning
Theoretical Interpretations of Learning
• Pavlov – Neural connections between brain areas of learning and responding acquired
• Other psychologists– Cognition plays central role in learning
• Place learning and cognitive map
• Latent learning
• Insight learning – sudden problem solving
• Learning set – learned to learn insightfully
Monkeys and Impact of Experience
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Trials
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Problems
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Basic Principles of Learning
Modeling: Learning by Watching Others
• Bandura – people learn through modeling– Demonstrates role of cognition in learning
– Cognitive learning occurs by watching before behavior occurs• Learn skills• Use of appropriate behavior in given situation• Reduce inhibitions• Learn what behaviors are reinforced
Basic Principles of Learning
Modeling
• Powerful form of learning
• Vicarious reinforcement – likely to imitate reinforced behaviors
• Vicarious punishment – likely not to imitate behaviors that are punished
• High status, attractive, likeable, successful models more likely imitated– Concerns about television, movies, other media
Basic Principles of Learning
Biological Factors in Learning
• Learning influenced several ways– Physical ability limitations (ie: fish cannot fly)
– Individual differences – (ie: fear inhibitions)
– Process of evolution – useful fears and survival mechanisms • Biological preparedness to learn• Learned taste aversion ( used on humans
and animals)
The End
Basic Principles of Learning