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Slide 1 6 Basic Principles of Learning © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 2 Basic Principles of Learning Slide 3 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Pavlov’s Experiment Observation screen Container of meat powder Revolving drum for recording responses Device to count drops of saliva © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Tube for collection of saliva Slide 4 Slide 5 Pavlov’s Experiment A Neutral stimulus (metronome) CR (salivation) Before classical conditioning: initially, the metronome is a neutral stimulus that does not elicit the response of salivation B UCR (meat powder) UCR (salivation) But the unconditioned stimulus (UCS) can elicit the unconditioned response (UCR) © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 6 Neutral stimulus (metronome) C UCR (meat powder) UCR (salivation) 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 CS (metronome) CR (salivation) Test of conditioning: after classical conditioning, the neutral stimulus becomes a conditioned stimulus (CS) that elicits the conditioned response (CR) of salivation © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 7 Pavlov’s Studies: the more often the metronome was associated in time with meat powder, the more effective in eliciting saliva 8 7 Number of drops of saliva elicited by metronome alone 6 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 8 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 9 Slide 10 Application of Terminology to Pavlov’s Experiment CS (meat powder) CR UCR (Salivation) UCS (metronome) © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 11 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 12 Slide 13 Watson and Raynor Study CS (rat) CR UCR UCS (loud noise) © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved (fear) Basic Principles of Learning Slide 14 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Basic Principles of Learning Operant Conditioning • Three types of desirable and undesirable consequences that influence behavior – Positive reinforcement – Negative reinforcement – Punishment © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 15 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 16 Use of Positive Reinforcement Increases Time Spent With Other Children Percent of interaction spent with 100 80 Adults 60 40 20 0 100 80 Children 60 40 20 0 0 2 4 6 8 10 12 14 Days © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 16 18 20 22 24 26 Slide 17 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 18 Slide 19 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 20 Primary reinforcer Secondary reinforcer © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 21 Slide 22 Patterns of Behavior Produced by Reinforcement Fixed Ratio Time © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Variable Ratio Time 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) © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 23 Slide 24 Patterns of Behavior Produced by Reinforcement Fixed Interval Time © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Variable Interval Time Slide 25 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Operant Conditioning Signal lights Slide 26 Speaker Lever Pellet dispenser To shock generator Dispenser tube Food cup Electric grid © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Basic Principles of Learning Slide 27 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 28 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Basic Principles of Learning Slide 29 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Basic Principles of Learning Slide 30 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 31 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 32 Slide 33 Stimulus Generalization and Reinforcement of a Pigeon’s Pecking Mean total responses 300 200 100 0 460 480 500 520 540 560 Wavelength © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 580 600 620 640 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 34 Slide 35 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Basic Principles of Learning Slide 36 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Basic Principles of Learning Slide 37 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Monkeys and Impact of Experience 120 Slide 38 Problems 257-312 201-256 101-200 25-32 17-24 9-16 1-8 110 100 90 80 70 60 50 1 2 3 4 Trials © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 5 6 Basic Principles of Learning Slide 39 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 40 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 © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved 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) © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved Slide 41 Slide 42 Basic Principles of Learning 6 The End © 2007 The McGraw-Hill Companies, Inc. All Rights Reserved