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PSYCHOLOGY (8th Edition) David Myers PowerPoint Slides Aneeq Ahmad Henderson State University Worth Publishers, © 2006 1 Learning Chapter 8 Prominent researchers — Pavlov, Thorndike, Watson, and Skinner — have greatly influenced today’s thinking about how learning takes place. This program examines the basic principles of classical and operant conditioning elaborated by these renowned figures. With Dr. Howard Rachlin of the State University of New York at Stony Brook and Dr. Robert Ader of the University of Rochester. Updated. 2 Learning How Do We Learn? Classical Conditioning Pavlov’s Experiments Extending Pavlov’s Understanding Pavlov’s Legacy Operant Conditioning Skinner’s Experiments Extending Skinner’s Understanding Skinner’s Legacy Contrasting Classical & Operant Conditioning Learning by Observation Bandura’s Experiments Applications of Observational Learning Learning is a relatively permanent change in an organism’s behavior due to experience. 3 How Do We Learn? We learn by association. Our minds naturally connect events that occur in sequence. 2000 years ago, Aristotle suggested this law of association. Then 200 years ago Locke and Hume reiterated this law. Learning => relatively permanent change in behavior due to experience / association TYPES OF Classical Conditioning Operant Conditioning LEARNING Observational Learning 4 Classical Conditioning Operant Conditioning Observational Learning 5 6 Classical Conditioning Sovfoto Ideas of classical conditioning originate from old philosophical theories. However, it was the Russian physiologist Ivan Pavlov who elucidated classical conditioning. His work provided a basis for later behaviorists like John Watson and B. F. Skinner. Ivan Pavlov (1849-1936) 7 Pavlov’s Experiments Before conditioning, food (Unconditioned Stimulus, US) produces salivation (Unconditioned Response, UR). However, the tone (neutral stimulus) does not. 8 Pavlov’s Experiments During conditioning, the neutral stimulus (tone) and the US (food) are paired, resulting in salivation (UR). After conditioning, the neutral stimulus (now Conditioned Stimulus, CS) elicits salivation (now Conditioned Response, CR) 9 Operant & Classical Conditioning 1. Classical conditioning forms associations between stimuli (CS and US). Operant conditioning, on the other hand, forms an association between behaviors and the resulting events. 10 Stimulus-Stimulus Learning Learning to associate one stimulus with another. 11 Stimulus-Stimulus Learning Learning to associate one stimulus with another. 12 Response-Consequence Learning Learning to associate a response with a consequence. 13 Response-Consequence Learning Learning to associate a response with a consequence. 14 Classical Conditioning = > Pavlovian Conditioning => type of conditioning in which an organism comes to associate stimuli. A NEUTRAL stimulus that after learning signals a conditioned (learned) response. Unconditioned Stimulus => a stimulus that unconditionally (naturally / automatically) triggers some type of response Unconditioned Response => the unlearned, naturally occurring response to the UCS. See Chickie and Pete’s Neutral Stimulus => produces NO response Conditioned Stimulus => an originally irrelevant stimulus that once paired w/ UCS eventually triggers a response Conditioned Response => the learned response to a previously neutral conditioned stimulus Jim trains Dwight video 15 “…Can!” Label the following: 1.UCS 2.UCR 3.CS 4.CR Describe the different phenomena associated with the learning that you observed in essay format below: 16 Based on the activity and your observations explain the following: Acquisition = Stimulus Generalization = Stimulus Discrimination = Extinction = Spontaneous recovery = 17 Acquisition Acquisition is the initial stage in classical conditioning in which an association between a neutral stimulus and an unconditioned stimulus takes place. 1. In most cases, for conditioning to occur, the neutral stimulus needs to come before the unconditioned stimulus. 2. The time in between the two stimuli should be about half a second. 18 Acquisition The CS needs to come half a second before the US for acquisition to occur. 19 Extinction When the US (food) does not follow the CS (tone), CR (salivation) begins to decrease and eventually causes extinction. 20 Spontaneous Recovery After a rest period, an extinguished CR (salivation) spontaneously recovers, but if the CS (tone) persists alone, the CR becomes extinct again. 21 Stimulus Generalization Tendency to respond to stimuli similar to the CS is called generalization. Pavlov conditioned the dog’s salivation (CR) by using miniature vibrators (CS) on the thigh. When he subsequently stimulated other parts of the dog’s body, salivation dropped. 22 Stimulus Discrimination Discrimination is the learned ability to distinguish between a conditioned stimulus and other stimuli that do not signal an unconditioned stimulus. 23 Criticisms of Pavlov’s Theory Pavlov and Watson considered consciousness, or mind, unfit for the scientific study of psychology. However, they underestimated the importance of cognitive processes and biological constraints. learning is constrained by an animal’s biology… However, later behaviorists suggested that animals learn the predictability of a stimulus, meaning they learn expectancy or awareness of a stimulus (Rescorla, 1988). 24 Biological Predispositions Courtesy of John Garcia Garcia showed that the duration between the CS and the US may be long (hours), but yet result in conditioning. A biologically adaptive CS (taste) led to conditioning and not to others (light or sound). John Garcia 25 Biological Predispositions Even humans can develop classically to conditioned nausea. 26 Pavlov’s Legacy Pavlov’s greatest contribution to psychology is isolating elementary behaviors from more complex ones through objective scientific procedures. Ivan Pavlov (1849-1936) 27 Applications of Classical Conditioning Brown Brothers Watson used classical conditioning procedures to develop advertising campaigns for a number of organizations, including Maxwell House, making the “coffee break” an American custom. John B. Watson 28 •Learning to Like => TV ADS •Learning to Fear •An object comes to be feared after being linked with a frightening stimulus •irrational fears of particular things, activities, or situations: high places, closed places, public places Little Albert 29 •An 11-month old boy – named “Albert” – was conditioned to fear a white laboratory rat •Each time he reached for the rat, Watson made a loud clanging noise right behind Albert •Albert’s fear generalized to anything white and furry Including rabbits and Santa Claus 30 NS “Little Albert” RAT Loud noise UR NO FEAR CS US CR 31 •In classical conditioning, the process of pairing a conditioned stimulus with a stimulus that elicits a response that is incompatible with an unwanted conditioned response. • fears and anxieties can be unlearned through Classical Conditioning •Desensitization Therapy – deep muscle relaxation techniques with degrees of anxiety levels (0-100) •Freud Unresolved inner conflicts = phobia represents other problems that is troubling the patient => Classical Conditioning is selective 32 Preparedness and Contrapreparedness (Seligman – Evolutionary Psych Perspective) Some stimuli are more suited to produce a fearful response =>Common objects of phobias are related to survival of humans through evolution (dark, heights, snakes, etc.) + our own personal experience influence our fears (handguns, outlets, foods, etc) Both interact to increase likelihood of certain kinds of conditioning and making other kinds less likely 33 Conditioned food/taste aversion -eat something => get sick for some reason = avoid it Can be a long time b/w CS (food) and US (illness) CR can last a long time –days, months, years Humans – food aversion to taste, smell, appearance Ex. Mr. Oz eating homemade chicken salad and getting sick Ex. Drinking alcohol & getting sick DID You KNOW…nausea = #1 cause for food aversion! •Reacting to Medical Treatments *Placebo effect vs. mind over matter? +/ 34 Applications of Classical Conditioning 1. Alcoholics may be conditioned (aversively) by reversing their positive-associations with alcohol. 2. Through classical conditioning, a drug (plus its taste) that affects the immune response may cause the taste of the drug to invoke the immune response. 35 nderestimated the importance of cognitive processes (thoughts, perceptions, expectations) of biological constraints on learning capacity redictabillity = 2 significant events occur close together in time an animal can predict the 2nd event id you know? The more predictable the association, the stronger the conditioned response will be nimals learn an awareness or expectancy of how likely it is that the UCS will occur he environment and evolutionary history or biological predispositions make it easy for particular associations which enhance an animal’s survival f you become ill after eating mussels, you will probably have a hard time eating them again ow I have a food aversion to chicken arcia and Koelling are 2 famous experimenters who taught us much about conditioning and learning eople tend to fear snakes and spiders rather than flowers b/c such animals can harm us more frequently than do flowers…Seligman – Preparedness vs. contrapreparedness nimals and humans are prepared to learn things crucial for their survival => Darwin’s theory of natural selection, and thus learning enables them to adapt to their environments iolent loud noises (UCS) were paired with a white rat (NS=>CS) to show how a specific fear might be conditioned ittle Albert became Watson and Rayner’s famous experiment ne phobia => fear of a white rat would later be GENERALIZED by Albert to fear almost anything white and / or furry ie. Rabbit, beard etc. 36 INI, VIDI, VICI PAVLOV’s Legacy! Operant & Classical Conditioning 2. Classical conditioning involves respondent behavior that occurs as an automatic response to a certain stimulus. Operant conditioning involves operant behavior, a behavior that operates on the environment, producing rewarding or punishing stimuli. Big Bang Theory 37 Classical Conditioning Respondent Behavior (automatically) Operant Conditioning Operant Behavior (acts on environment) •Organism associates its behavior with rewards and consequences •subjects are more likely to repeat rewarded (reinforced) behavior •less likely to repeat punished behaviors THORNDIKE => Law of Effect = REWARDED behavior is likely to recur! 38 THORNDIKE Puzzle Box 39 Skinner’s Experiments Skinner’s experiments extend Thorndike’s thinking, especially his law of effect. This law states that rewarded behavior is likely to occur again. Yale University Library 40 Operant Chamber The operant chamber, or Skinner box, comes with a bar or key that an animal manipulates to obtain a reinforcer like food or water. The bar or key is connected to devices that record the animal’s response. 41 Walter Dawn/ Photo Researchers, Inc. 42 From The Essentials of Conditioning and Learning, 3rd Edition by Michael P. Domjan, 2005. Used with permission by Thomson Learning, Wadsworth Division Skinner Box Using Thorndike's law of effect as a starting point, Skinner developed the Operant chamber, or the Skinner box, to study operant conditioning. 1. Operant Response = chosen behavior => cats desire to get out of the box or to get food 2.Consequences = follows behavior =>receiving food or freedom after pressing button Types of Consequences a. Reinforcers (rewards) • INCREASES the likelihood that the behavior will be repeated +reinforcement = adds something rewarding to the situation -reinforcement = subtracts something unpleasant from situation 43 b. punishments •weaken behavior by adding something unpleasant •reduces the likelihood that behavior will reoccur •most effective when it is strong, immediate and consistent •can have undesirable side effects 44 Punishment Although there may be some justification for occasional punishment (Larzelaere & Baumrind, 2002), it usually leads to negative effects. 1. 2. 3. 4. Results in unwanted fears. Conveys no information to the organism. Justifies pain to others. Causes unwanted behaviors to reappear in its absence. 5. Causes aggression towards the agent. 6. Causes one unwanted behavior to appear in place of another. 45 Shaping Shaping is the operant conditioning procedure in which reinforcers guide behavior towards the desired target behavior through successive approximations. Fred Bavendam/ Peter Arnold, Inc. Khamis Ramadhan/ Panapress/ Getty Images A rat shaped to sniff mines. A manatee shaped to discriminate objects of different shapes, colors and sizes. 46 Primary & Secondary Reinforcers 1. Primary Reinforcer: An innately reinforcing stimulus like food or drink and SEX …or heavy petting and 10 sec frencher if you prefer! 2. Conditioned (secondary)Reinforcer: A learned reinforcer that gets its reinforcing power through association with the primary reinforcer. 47 Immediate & Delayed Reinforcers 1. Immediate Reinforcer: A reinforcer that occurs instantly after a behavior. A rat gets a food pellet for a bar press. 2. Delayed Reinforcer: A reinforcer that is delayed in time for a certain behavior. A paycheck that comes at the end of a week. We may be inclined to engage in small immediate reinforcers (watching TV) rather than large delayed reinforcers (getting an A in a course) which require consistent study. Small, immediate reinforcements wins! => more alluring than big delayed reinforcement. SPEAKS TO THE POWER OF ADDICTION: SEX, GAMBLING, SMOKING, DRUGS, SHOPPING! 48 TERM DEFINITION EXAMPLE Outcome on Learning Continuous Reinforcement Reinforcing behavior every time it happens Getting Oz Bucks every time you answer a question in class Learning occurs rapidly; extinction occurs rapidly Partial (intermittent) Reinforcement Reinforcing behavior sometimes Gambling – playing the lottery Initial learning is slower; greater resistance to extinction “hope springs eternal” Fixed – Ratio Schedule Reinforce behavior after a set number of responses (attempts) Piecework; Often subject will pause only briefly after reinforcement, then returns to high rate of responses / attempts Variable – Ratio Schedule Provides reinforcement after an unpredictable number of responses / attempts Gambling, fishing or hunting; Oz Bucks on varying responses Produces high rates of responding b/c reinforcement increases as the responses/ attempts increase Reinforce 1st response / attempt after a set / fixed time period Waiting for your college acceptance letter in the mail; waiting for the cookies to be done More frequent attempts/ responses as the time for reinforcement grows near; start-stop work pattern Reinforce the 1st response / attempt after VARYING TIME intervals POP quiz Produces slow steady responding; subject doesn’t know when reinforcement will49 occur – therefore paces themselves Fixed Interval Schedule Variable Interval – Schedule Schedules of Reinforcement 50 Motivation Intrinsic Motivation: The desire to perform a behavior for its own sake. Extrinsic Motivation: The desire to perform a behavior due to promised rewards or threats of punishments. 51 effect of promising a reward for doing what one already likes to do. The person may now see the reward, rather than intrinsic interest, as motivation for performing the task. Are NCAA athletics like a job/ business? Does getting paid (overjustification) = burnout? Should athletes get PAID TO PLAY? What do you think? 52 Types of Reinforcers Any event that strengthens the behavior it follows. A heat lamp positively reinforces a meerkat’s behavior in the cold. Reuters/ Corbis 53 Punishment An aversive event that decreases the behavior it follows. 54 Extending Skinner’s Understanding Skinner believed in inner thought processes and biological underpinnings, but many psychologists criticize him for discounting them. 55 Psych Sim Operant Conditioning Worksheet 56 The scenario (scary as it may be): All of a sudden a creepy looking guy with a mustache driving a White SUV pulls into the student parking lot. He says, “hey I’m lost. Can you give me directions to the Oxford Valley Mall?” With that you take out a piece of paper and write… Directions to the Oxford Valley Mall – leaving from the student parking lot at the bottom of the hill…. 57 Tolman is best known for his idea of latent learning Tolman’s experiment used rats trying to find their way through a maze. Some rats were rewarded and others were not rewarded. I consider latent learning a COGNITIVE MAP. When I need to I can call up the mental stored image (spatial memory) and put it to use. ***Learning involves more than a change in observable behavior, it also involves changes in unobservable mental processes that may or may not be reflected at some future time (latent learning). Learning occurs even before the subject reaches the end of the maze & occurs whether or not the learner is reinforced Those that were reinforced did indeed run the maze faster and with fewer errors. BUT…others that were not reinforced, had learned a lot about the maze as they wandered, maybe even more My learning was LATENT – I than the rats that stored it internally for later use. were rewarded. You just did not see it in my behavior. Give me some food and then I will put my latent learning to use and get out of the maze quickly! 58 Cognition & Operant Conditioning Evidence of cognitive processes during operant learning comes from rats during a maze exploration in which they navigate the maze without an obvious reward. Rats seem to develop cognitive maps, or mental representations, of the layout of the maze (environment). Insight & Latent Learning Chimpanzee Problem Solving Chimpanzee Problem Solving 59 Latent Learning Such cognitive maps are based on latent learning, which becomes apparent when an incentive is given (Tolman & Honzik, 1930). 60 Operant vs. Classical Conditioning 61 Biological Predisposition Photo: Bob Bailey Biological constraints predispose organisms to learn associations that are naturally adaptive. Breland and Breland (1961) showed that animals drift towards their biologically predisposed instinctive behaviors. Marian Breland Bailey 62 Skinner’s Legacy Skinner argued that behaviors were shaped by external influences instead of inner thoughts and feelings. Critics argued that Skinner dehumanized people by neglecting their free will. Falk/ Photo Researchers, Inc . 63 Applications of Operant Conditioning Skinner introduced the concept of teaching machines that shape learning in small steps and provide reinforcements for correct rewards. LWA-JDL/ Corbis In School 64 Applications of Operant Conditioning Reinforcement principles can enhance athletic performance. In Sports 65 Applications of Operant Conditioning Reinforcers affect productivity. Many companies now allow employees to share profits and participate in company ownership. At work 66 Applications of Operant Conditioning In children, reinforcing good behavior increases the occurrence of these behaviors. Ignoring unwanted behavior decreases their occurrence. 67 © Herb Terrace Higher animals, especially humans, learn through observing and imitating others. ©Herb Terrace The monkey on the right imitates the monkey on the left in touching the pictures in a certain order to obtain a reward. 68 Reprinted with permission from the American Association for the Advancement of Science, Subiaul et al., Science 305: 407-410 (2004) © 2004 AAAS. Mirror Neurons Neuroscientists discovered mirror neurons in the brains of animals and humans that are active during observational learning. 69 Learning by observation begins early in life. This 14-month-old child imitates the adult on TV in pulling a toy apart. Meltzoff, A.N. (1998). Imitation of televised models by infants. Child Development, 59 1221-1229. Photos Courtesy of A.N. Meltzoff and M. Hanuk. Imitation Onset 70 Courtesy of Albert Bandura, Stanford University Bandura's Bobo doll study (1961) indicated that individuals (children) learn through MODELING and imitating others who receive rewards and punishments. 71 Applications of Observational Learning Unfortunately, Bandura’s studies show that antisocial models (family, neighborhood or TV) may have antisocial effects. 72 Positive Observational Learning Bob Daemmrich/ The Image Works Fortunately, prosocial (positive, helpful) models may have prosocial effects. 73 Gentile et al., (2004) shows that children in elementary school who are exposed to violent television, videos, and video games express increased aggression. Ron Chapple/ Taxi/ Getty Images Television and Observational Learning 74 Children modeling after pro wrestlers Glassman/ The Image Works Bob Daemmrich/ The Image Works Research shows that viewing media violence leads to an increased expression of aggression. 75 “Building Phase” of conditioning the strengthening or “speeding up” of the learning of a desired response Diminishing returns - holds true for both = amount of learning gradually becomes smaller until no further learning occurs Classical Conditioning -simple -Trials repeated pairing of stimuli (US w/ CS ) Operant Conditioning -more complicated -behavior is voluntary => harder to teach -Therefore, you must: motivation restrict the environment (skinner box) Shaping - reinforcing gradual progressions toward desired behavior(“Getting warmer!”) Size of block = amount of new learning Spacing of trials = time b/w 1 paring and the next is equally important as the # of trials intermittent pairing = pairing the CS w/ US on only some trials & presenting them separately on other trials; reduces both the rate of learning & final level of learning achieved -animal training -greatest learning occurs in first few trials 76 Things to know: Definitions of Classical Conditioning, Operant Conditioning, Observational Learning Application to situations Reinforcement Schedules Examples, application Aspects of conditioning – definitions / application UCS, UCR, CS, CR Acquisition Generalization Discrimination Extinction Spontaneous recovery Aversions / phobias Overjustification Learning Personalities Pavlov, Skinner, Thorndike, Watson, Garcia and Koelling, Bandura shaping vs. modeling reinforcement primary vs. secondary continuous vs. partial positive / negative reinforcement; punishment effects on learning (speed of acquisition, extinction etc.) Critics of various learning theories Cognitive processes Biological / evolutional predispositions Latent learning 77 Prior chapter ?’s