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6. 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
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6 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 • 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
Observation screen Container of meat powder Revolving drum for recording responses Tube for collection of saliva Device to count drops of saliva Pavlov’s Experiment
A Before classical conditioning: initially, the metronome is a neutral stimulus that does not elicit the response of salivation Neutral stimulus (metronome) CR (salivation) B But the unconditioned stimulus (UCS) can elicit the unconditioned response (UCR) UCR (meat powder) UCR (salivation) Pavlov’s Experiment
UCR (meat powder) Neutral stimulus (metronome) UCR (salivation) C 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) D Test of conditioning: after classical conditioning, the neutral stimulus becomes a conditioned stimulus (CS) that elicits the conditioned response (CR) of salivation CS (metronome) CR (salivation)
Basic Principles of Learning 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
Pavlov’s Studies: the more often the metronome was associated in time with meat powder, the more effective in eliciting saliva 8 7 6 Number of drops of saliva elicited by metronome alone 5 4 3 2 1 1 2 3 4 5 6 7 8 9 10 11 Number of times metronome and meat powder were presented together
Basic Principles of Learning 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
Application of Terminology to Pavlov’s Experiment CS (meat powder) CR (Salivation) UCR UCS (metronome)
Basic Principles of Learning 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
CS (rat) CR (fear) UCR UCS (loud noise) Watson and Raynor Study
Basic Principles of Learning 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 Positive Reinforcement • Positive consequences – behavior occurs more frequently (ie: praise given) • Uses in teaching • Hospitalized schizophrenics more normal behaviors • Employees within the workplace • Operant response – changed behavior becomes more frequent
Percent of interaction spent with 100 80 60 Adults 40 20 0 100 80 60 Children 40 20 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Days Use of Positive Reinforcement Increases Time Spent With Other Children
Basic Principles of Learning Positive Reinforcement • Two important issues • Timing of reinforcer following response • Delay of reinforcement – the greater the delay between response and reinforcer, the slower the learning • Consistency in delivery of reinforcement • Schedules of reinforcement
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
Primary reinforcer Secondary reinforcer
Basic Principles of Learning 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
Fixed Ratio Variable Ratio Cumulative responses Cumulative responses Time Time Patterns of Behavior Produced by Reinforcement
Basic Principles of Learning 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)
Fixed Interval Variable Interval Cumulative responses Cumulative responses Time Time Patterns of Behavior Produced by Reinforcement
Basic Principles of Learning 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
Speaker Signal lights Lever Pellet dispenser To shock generator Dispenser tube Food cup Electric grid Operant Conditioning
Basic Principles of Learning 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 ofPunishment • 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 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
300 200 Mean total responses 100 0 460 480 500 520 540 560 580 600 620 640 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
Problems 120 257-312 110 201-256 101-200 100 25-32 17-24 90 9-16 Percent of correct responses 1-8 80 70 60 50 1 2 3 4 5 6 Trials Monkeys and Impact of Experience
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)
Basic Principles of Learning 6 The End