Learning (AP Notes) We ll study five kinds of learning: Kind Main Contributor Emphasis

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1 Learning (AP Notes) Definition: Learning is a relative permanent change in an organism s behavior due to experience. Or, the ability to profit from experience. We ll study five kinds of learning: Kind Main Contributor Emphasis Classical Conditioning (a.k.a. Pavlovian Conditioning, Stimulus-Response (SR) Learning, Associative learning) Instrumental Conditional Operant Conditioning (a.k.a. Reinforcement Theory, Instrumental Conditioning) Latent Learning (A kind of learning that does not require any reinforcement nor association for it to be remembered.) Observational Learning (a.k.a. Social Learning Theory) Ivan Pavlov (1904) Edward L. Thorndike (1906) B.F. Skinner ( s) E.C. Tolman ( s) Albert Bandura (1960s) Learning by association. Pairing one stimuli with another to bring about a response. Pioneered the Law of Effect the idea that behavior is shaped by its consequences. Further developed the science of conditioning by emphasizing role of rewards or punishments in shaping behavior. Learning that remains hidden until it is needed. Utilizes a kind of cognitive map of experiences. Learning from observing usually through modeling and imitation. PAGE 1

2 Classical Conditioning Pioneered by Ivan Pavlov Nobel Prize winning Russian Physiologist Nobel Prize in 1904 for his study of the digestive system (salivary response) His famous dog experiments what was going wrong? Dogs were salivating at the wrong time. He decided to study what was going on and ended up inventing the concept of the Conditioned Response which greatly contributed to the psychology of learning. He developed the first real learning curve involving the stages of Acquisition when the behavior is first learned Extinction when the behavior dies out because associations are not made or presented Time Delay Spontaneous Recovery after a time delay, the behavior may resurface on its own Re-extinction behavior goes away again Reconditioning the relearning of a previously extinguished behavior, this usually takes much less time than the initial Acquisition phase. PAGE 2

3 Key Pavlovian Terms Term Explanation Example UCS Unconditioned Stimulus UCR Unconditioned Response CS Conditioned Stimuli CR Conditioned Response Acquisition Stimulus Generalization Stimulus Discrimination Extinction Spontaneous Recovery Any stimuli that naturally brings about a response (no training is required for the stimuli to cause a response) A response that did not have to be trained. Any stimuli that through training now brings about a response. A behavior that had to be taught in response to a specific stimuli. This is the initial stage of the conditioning process, it s when the NS is paired with the UCS to bring about a response. Responding in the same way to similar stimuli. Responding differently to stimuli that are not similar to each other. When a CS is no longer able to bring about a CR The revival of what was once thought to be an extinguished response. A loud noise will naturally cause a startle response. Your mouth watering at the smell of fresh baked bread. Different colors of traffic lights. Prior to learning to drive, the red light had no effect on you. Actually stopping your car when you see the red stimuli. A child learns to fear (CR) the doctor s office (CS) by associating it with the reflexive emotional reaction (UCR), to a painful injection (UCS) The presence of any principal in the hall will cause students to slow down and stop running. Students stop running only when certain teachers are in the hall (substitutes get clobbered) Cry wolf when there is no wolf and soon nobody will respond to help you Someone starts smoking again after having quit for a long period of time (drinkers too). PAGE 3

4 Some Practical Uses (Therapy) Wrap Up Flooding Throwing you in a room with 1 million spiders. Systematic Desensitization gradually exposing you over time, in a non-threatening way, to spiders. Counterconditioning Cookie Treatment or getting rid of Little Albert s fear but making him fat in the process. Bell-and-Pad Method for Bedwetting Taste Aversions what are they and why are they so powerful? S-R learning is a powerful kind of learning But, can it explain higher kinds of learning like math, or how to learn the lead part in a play. The organism (person, dog) seems very passive the person (or dog) isn t active at all they just sit back and respond to stimuli. Very knee-jerk (reflex) kind of learning. Maybe..... John Garcia (1966) found and proved the biological limits to conditioning. Pavlov & friends claim that ANYTHING can be learned through conditioning. Garcia s work with taste aversion in rats showed that, contrary to behaviorists, we come into the world already hardwired to learn some things and not others. So much for the tabula rasa idea that behaviorists love to promote. Robert Rescorla (1972) his work showed that S-R learning isn t as simple and mindless as early behaviorist thought. What is really happening when an animal associates a stimulus with a response is that the animal is learning the predictability of the second event! Rescorla s Study: If a shock always is preceded by a tone, and then sometimes also by a light that accompanies the tone, a rat will react with fear to the tone but not the light. Although the light always is followed by the shock, the tone better predicts impending shock. The more predictable the association, the stronger the conditioned response. It s as if the animal learns an expectancy, an awareness of how likely it is that the UCS will occur. The rat is thinking, just like a scientist, watching which stimulus is paired with what response. (That thinking little devil!) Thus, Rescorla concluded that S-R learning is not a stupid process by which the organism willy-nilly forms associations between any two stimuli that happen to occur. Even in PAGE 4

5 classical conditioning, leaning is not the simple CS-UCS association, it s not a simple stamping in of a new response to a stimuli, it s the thought that counts. Rescorla s work explains why Ana-Buse (aversive conditioning) doesn t automatically cure alcoholism! PAGE 5

6 John Watson (1920) & Behaviorism Bought into Pavlov s ideas about classical conditioning hook, line and sinker. President of the APA in 1915 Distinguished professor of psychology at Johns Hopkins Promoted Behaviorism the school of psychology that believes that only overt (observable) behavior is the proper subject of psychological inquiry. Psychology ought to be a pure science, we should only study behavior we can observe and measure (tremendous rejection of Freudian ideas of an inner-self or an unconscious mind ). Human behavior, Watson believed, was nothing more than a bundle of conditioned responses. We come into the world a tabula rasa, and we are conditioned by society to be who we are. Case of Little Albert (1920) Watson and Rosalie Rayner conditioned fear into an 11 month old little boy. This was done to disprove the Freudian idea that phobias are symbolic manifestations of unconscious conflicts that arise from early childhood sexual conflicts. Nonsense, said Watson. Watch, I ll show you that phobias are merely learned responses. Pavlov was right, everything is the result of classical conditioning. So strong was Watson s belief in the power of conditioning he made the statement that if you gave him a healthy children at birth, and let him control all their conditioning, he ll produce whatever kind of adult person you want, beggar, thief, saint, etc. Operant Conditioning First developed as Instrumental Conditioning by E. Thorndike (1900s) who promoted the Law of Effect (know it) behavior followed by a satisfying state of affairs is strengthened and a behavior followed by an annoying state of affairs is weakened. The reinforcing value of the consequence is instrumental in whether or not the behavior will be conditioned. Skinner ( ) improved on Thorndike s ideas and coined the name Operant Conditioning to describe what is really going on. The person (or dog) actually plays an important role in the learning. They do something (operate on the environment, such as pulling a lever on a slot machine) which causes a consequence (change in environment causes apples & oranges to spin) and if the consequence (three apples) is rewarding (jack pot!) the behavior is strengthened (is reinforced) and will occur again; however if the consequence is unpleasant (punisher you lose all your money) the behavior will usually diminish. PAGE 6

7 Skinner was a brilliant experimental psychologist working at Harvard where in the lab he built elaborate and very technical Skinner Boxes to use in thousands of experiments on animals (rats, pigeons) in investigating is theory of learning by reinforcement. (Ask about his Heir Crib ) A Skinner Box is a tightly controlled laboratory device designed for conditioning where reinforcers/punishers are tightly controlled, dispensed and measured. PAGE 7

8 Key Operant Terms Term Explanation Example Reinforcement The process by which a stimulus increases the chances that the preceding behavior will occur again Paying someone money to do something. Primary Reinforcers Second-Order Conditioning Secondary Reinforcer (a.k.a. Conditioned Reinforcers) Positive Reinforcer (Rewards) Negative Reinforcer Avoidance & Escape Conditioning Punishers Reinforcers that function due to the biological makeup of the organism When a CS acts like an UCS, creating conditioned stimuli out of events associated with it. Reinforcers that have to acquire their value by being paired with something desirable. Any reinforcer that increases the frequency of a behavior. Works best if reinforcer is immediate not delayed. Any behavior that will occur again because it helped remove some unpleasant stimulus. Avoiding exposure to a stimulus; responding to end and aversive stimuli. A consequence that will stop a behavior. Using food, water or promise of sleep to get someone to do something. When a child suffers the pain of an injection (UCS) at a doctor s office, noticeable stimuli like the doctor s white coat that precede and predict the UCS can become a conditioned stimuli for fear. Using money, status or good grades as a reward. These can be cashed in for more valuable primary reinforcers. Using praise, money or whatever a person likes to get them to do something the more immediate the better Moving out of the hot sun, muting commercials, moving away from someone who smells bad. I avoid food I don t like; when it s put on my plate, I get up and leave. Spanking, electric shock. PAGE 8

9 Problems with Relying Solely on Punishers to Modify Behavior Does not in itself teach what to do (alternative acceptable behaviors) Works only when guaranteed to occur got to be consistent. Might cause avoidance or escape behavior. Can create anger and hostility toward person administering punishment. (Could bottle this up and explode at a later time) Might create future punishers my Dad hit me so I ll hit my kids. Might actually lead to increased behavior kids see it as the only way to get attention so they increase the behavior. Schedules of Reinforcement Two Major Groups Interval Schedules rely on the passage of time before you get your reward/punishment Ratio Schedules the person (or dog) must make a certain number of responses before he gets his reward/punishment. PAGE 9

10 FIVE SCHEDULES OF REINFORCEMENT Fixed Ratio Variable Ratio Fixed Interval Variable Interval Continuous (Actually not a very good reinforcer, it quickly leads to habituation boredom) There is a fixed number of responses that must occur before you get the reward The number of responses will vary before you get the reward There s a set amount of time that must pass after you do a behavior before you get a reward Don t know how much time must pass before you get the reward. Each and every response gets a reward. 1:3 schedule. Every three times you pull the lever you ll get a prize The # of times you have to pull the lever changes every time like a slot machine Getting paid every two weeks. Or, getting a phone call from boy/girl friend every two hours. Don t know when boy/girl friend will call. Never know when a teacher will praise you. Teacher praises you no matter what you do. Other Important Concepts! Shaping (a.k.a. Behavior Modification ) Token Economies what are they & do they work? Instinctive Drift or why animals revert to animal behavior after so much training. PAGE 10

11 Latent Learning Edward Tolman (1932) Stresses cognitive processes in learning (or how the mind is active in the learning process) Latent learning occurs even though there is no immediate reinforcement (contradicts Skinner s Reinforcement Theory) It s a kind of hidden learning that gets tucked away for future use even though it has little (if any) immediate reward value Classic Study: Tolman (1932) had three groups of rats run individually through a maze once a day for 10 days. One group received food as a positive reward for reaching the end of the maze, and the other two groups did not. The rewarded rats quickly learned to run through the maze with few wrong turns, while the nonrewarded rats did not. Beginning on the eleventh day, one of the groups of nonrewarded rats was also positively rewarded with food for reaching the end of the maze. The next day that group ran the maze as efficiently as the previously rewarded group did, while the remaining, still nonrewarded group continued to perform poorly. This demonstrated latent learning. The rats that were not rewarded until the eleventh day had learned the route to the end of the maze, but they revealed this learning only when rewarded for doing so. Donahue s observation: I bet that the last nonrewarded group of rats also secretly learned the maze as well as the others. But they were probably thinking to themselves Why should we perform for these clowns if they re not going to reward us? PAGE 11

12 Latent learning also explains formation of cognitive maps Bet you have a cognitive map of: How to get to and from school What a three dimensional cube looks like Or a step-by-step outline of how to change a light bulb Or, a cognitive map of the layout of a typical grocery store like Food Lion or Ukrops looks like. Bet you have a pretty good cognitive map of Notre Dame Univ. even though you ve never been there. Observational Learning Stresses learning by modeling, imitation and observing others Albert Bandura s famous Bobo Doll study on whether or not aggression and violent acts is a learned phenomenon from watching others act aggressively. This approach especially explains how we learn social & gender roles. Essential to Bandura s Social Learning Theory which assumes behavior is learned chiefly through observation and the mental processing of information. Key Factors to learning this way: 1. You must pay attention to the model s actions. 2. You must remember the model s actions. 3. You must have the ability to produce the actions. 4. You must be motivated to perform the actions. This might explain, why we don t automatically learn from whatever role model is put in front of us. Instead, there seems to be a great deal of cognitive assessment going on in the head of the learner as to whether or not behavior he sees will be imitated. Might explain the selected effects of prosocial behavior or role models such as Martin Luther King, Gandhi etc. It s important that models practice what they preach. Not everyone copies such noble behavior. Because we don t imitate all models. We have to buy into their value system and hold them in high regard; we re more likely to imitate models that we admire, and we tend to copy behavior that we see gets rewarded. PAGE 12

13 And, OL can also promote undesirable behavior. We can develop phobias vicariously through observing people who exhibit them. A study of people with spider phobia found that 71% traced it to OL, 57% to CC, and 45% to their knowledge of spiders. Even monkeys can develop fears (of snakes) through observing other monkeys. Rhesus monkeys watched videotapes of monkey models showing fear of presumably fear-relevant stimuli (toy snakes or a toy crocodile) or presumably fear-irrelevant stimuli (flowers or a toy rabbit). The monkeys developed fears of the fear-relevant, but not the fear-irrelevant, stimuli. Perhaps they are prepared by evolution to do so, because such fears have survival value. Wrap Up 1. Could you explain the similarities & differences between Classical and Operant Conditioning? 2. Can you explain the contributions of John Garcia & Robert Rescorla s research on the biological determinants of learning and conditioning? 3. Are you able to explain Albert Bandura s famous Bobo Doll experiment? 4. Do you know the basic stages of conditioning: Acquisition, Extinction, Time Delay, Spontaneous Recovery, Re-extinction, Reconditioning. 5. Can you clearly explain the difference between a punisher and negative reinforcement? 6. Can you give clear examples of the different schedules of reinforcement? 7. What does latent learning and the social learning theory suggest about the role of cognition in learning? PAGE 13

14 Question: Does TV (media) cause violence? Did you know that in the average home the TV set is on 7 hrs per day? Individual members watch an average 4 hrs per day. That by the time a kid is in high school he/she will have sat in front of a TV set 2.6 years straight? Women watch more than men, non-whites more than whites, preschoolers and retired people more than those in school or working, less educated more than the highly educated. Studies of prime time shows (and Saturday morning) find that in the content of those programs - Six in ten programs contain violence - And by the end of elementary school the average kid will have seen 8,000 murders, 100,000 violent acts Most research shows that violence in the media: Does contribute to aggression People exposed to it behave more aggressively TV violence supplies aggressive skills Children especially are prone to imitate what they see Media violence provides aggressive scripts or ideas on how to behave in situations that seem to parallel those they have observed Kids who are constantly exposed to violence in media tend to think it is OK and tolerate it and are less likely to condemn it, they become desensitized to brutality Or is it a case of only those who are prone to violence become violent from a steady diet of it in the media Kids raised in homes where violence is not condoned or who have parents who discuss the topic and explain that TV violence is fake don t exhibit violent tendencies In USA and Canada murder rates doubled between 1957 and 1974 as TV spread Angered college students who viewed a violent film acted more aggressively than did similarly angered students who viewed nonaggressive films Immediately after viewing Power Rangers, kids committed seven times as many aggressive acts per 2-minute interval compared to nonviewers Before a kid gets into high school he s seen 100,000 violent episodes and some 20,000 murders Studies show that it s not the violent content itself that causes social violence but the arousal it produces Studies show that viewing violence disinhibits or seems to break down the normal restraint to act that way especially when popular cultural figures model it Media portrayals influence many kids to imitate what they see PAGE 14

15 What do you think happens when young, impressionable kids are fed a steady diet of Mortal Kombat, Jerry Springer and WWF Wrestling? APA (1993) statement: The irrefutable conclusion is that viewing violence increases violence - PAGE 15

16 HISTORICAL MILESTONES DATE (Approx.) THEORIST CONCEPT EXPLANATION 1905 Ivan Pavlov Classical Conditioning a.k.a Associative Learning, Pavlovian Conditioning, Stimulus-Response Learning 1905 Edward L. Thorndike Instrumental Conditioning & The Law of Effect While Pavlov was studying classical conditioning on in animals, Thorndike was studying animals intelligence and ability to solve problems. 1920s E.C. Tolman Latent Learning (Latent means hidden ) This is the first kind of learning scientifically developed. It is a procedure in which a neutral stimulus is paired with a stimulus that elicits a reflex or other response until the neutral stimulus alone comes to elicit a similar response. According to the law of effect a response made in the presence of a particular stimulus if followed by a satisfying consequence (reward) it is more likely to be made the next time the stimulus is encountered. Conversely, responses that produce discomfort are less likely to be performed again. This is called instrumental conditioning because responses are strengthened when they are instrumental (effective) in producing rewards. This is learning that is not evident when it first occurs. The organism develops something of cognitive map, that is, a mental representation of the particular spatial arrangement of whatever it is they are doing John Watson Behaviorism This is the extreme view that all behavior is the result of PAGE 16

17 Watson simply applied Pavlov s theories to all of human behavior. He became president of the APA and popularized conditioning as the explanation for human behavior. conditioning and that the only behavior psychologists ought to study is behavior that can be observed and measured (overt behavior). His experiments with Little Albert became famous B.F. Skinner Operant Conditioning a.k.a. Reinforcement Theory About 40 years after Thorndike s work, Skinner extended and formalized many of Thorndike s ideas. He was a brilliant experimental scientist at Harvard where he developed many innovative experimental procedures Skinner Boxes - to study the conditioning process 1965 Albert Bandura Observational Learning a.k.a. Vicarious Conditioning He called the process of learning operant conditioning because during conditioning an organism learns a response by operating on (doing something that brings about a change) the environment which will bring about a reward or a punisher which will influence whether or not the organism will do that behavior again. This is learning by watching others, imitating a model who demonstrates the behavior. His famous study with the Bobo Doll raised important issues regarding learned aggression. This is a powerful source of the socialization process through which children learn about which behaviors are and are notappropriate in their culture. PAGE 17