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Chapter 6 Learning This multimedia product and its contents are protected under copyright law. The following are prohibited by law: any public performance or display, including transmission of any image over a network; preparation of any derivative work, including the extraction, in whole or part, of any images; any rental, lease, or lending of the program. ISBN: 0-205-42428-7 1 Copyright © Allyn and Bacon 2006 Learning Learning – A process through which experience produces lasting change in behavior or mental processes Behavioral learning – Forms of learning that can be described in terms of stimuli and responses 2 Copyright © Allyn and Bacon 2006 Learning Three types of Learning • Classical Conditioning • Operant or Instrumental Learning • Cognitive or Social Learning 3 Copyright © Allyn and Bacon 2006 What Sort of Learning Does Classical Conditioning Explain? Classical conditioning is a basic form of learning in which a stimulus that produces an innate reflex becomes associated with a previously neutral stimulus, which then acquires the power to elicit essentially the same response 4 Copyright © Allyn and Bacon 2006 Demonstration 5 Copyright © Allyn and Bacon 2006 The Essentials of Classical Conditioning Neutral stimulus – Any stimulus that produces no conditioned response prior to learning Acquisition – Initial learning stage in classical conditioning; conditioned response becomes elicited by the conditioned stimulus 6 Copyright © Allyn and Bacon 2006 The Essentials of Classical Conditioning Unconditioned stimulus (UCS) Unconditioned response (UCR) Conditioned stimulus (CS) Conditioned response (CR) 7 Copyright © Allyn and Bacon 2006 The Essentials of Classical Conditioning Unconditioned stimulus (UCS) Unconditioned response (UCR) The stimulus that elicits an unconditioned response Conditioned stimulus (CS) Conditioned response (CR) 8 Copyright © Allyn and Bacon 2006 The Essentials of Classical Conditioning Unconditioned stimulus (UCS) Unconditioned response (UCR) Conditioned stimulus (CS) The response elicited by an unconditioned stimulus without prior learning Conditioned response (CR) 9 Copyright © Allyn and Bacon 2006 The Essentials of Classical Conditioning Unconditioned stimulus (UCS) Unconditioned response (UCR) Conditioned stimulus (CS) A previously neutral stimulus that comes to elicit the conditioned response Conditioned response (CR) 10 Copyright © Allyn and Bacon 2006 The Essentials of Classical Conditioning Unconditioned stimulus (UCS) Unconditioned response (UCR) Conditioned stimulus (CS) Conditioned response (CR) A response elicited by a previously neutral stimulus that has become associated with the unconditioned stimulus 11 Copyright © Allyn and Bacon 2006 Classical Conditioning Prior to conditioning Neutral stimulus (tone) (Orientation to sound but no response) Unconditioned stimulus (food powder in mouth) Unconditioned response (salivation) Conditioning Neutral stimulus CS (tone) + Unconditioned stimulus (food powder) Conditioned response (salivation) After conditioning Conditioned stimulus (tone) Conditioned response (salivation) 12 Copyright © Allyn and Bacon 2006 Classical Conditioning Extinction – Weakening of a conditioned association in the absence of an unconditioned stimulus or reinforcer Spontaneous recovery – Reappearance of an extinguished conditioned response after a time delay 13 Copyright © Allyn and Bacon 2006 (1) Acquisition (CS + UCS) (2) Extinction (CS alone) Rest period Strength of the CR (Weak) (Strong) Acquisition, Extinction, and Spontaneous Recovery (3) Spontaneous Recovery (CS alone) (Time) Trials 14 Copyright © Allyn and Bacon 2006 Classical Conditioning: Generalization and Discrimination Stimulus generalization involves giving a conditioned response to stimuli that are similar to the CS Stimulus discrimination involves responding to one stimulus but not to stimuli that are similar Confusing stimuli may cause experimental neurosis 15 Copyright © Allyn and Bacon 2006 Applications of Classical Conditioning Taste-aversion learning – Biological tendency in which an organism learns to avoid food with a certain taste after a single experience, if eating it is followed by illness 16 Copyright © Allyn and Bacon 2006 One Final Thought on Pavlov Why are some stimuli-consequence combinations readily learned while other combinations are highly resistant to learning? What any organism can or cannot learn in a given setting is due in part to its evolutionary history 17 Copyright © Allyn and Bacon 2006 How Do We Learn New Behaviors by Operant Conditioning? In operant conditioning, the consequences of behavior, such as rewards and punishments, influence the chance that our behavior will occur again 18 Copyright © Allyn and Bacon 2006 Skinner’s Radical Behaviorism B.F. Skinner believed that the most powerful influences on behavior are its consequences 19 Copyright © Allyn and Bacon 2006 How Do We Learn New Behaviors by Operant Conditioning? Trial-and-error learning – Learner gradually discovers the correct response by attempting many behaviors and noting which ones produce the desired consequences 20 Copyright © Allyn and Bacon 2006 Reinforcement vs Punishment • Reinforcement • Anything that increases a behavior or response • Punishment • Anything that decreases or stops a behavior/response 21 Copyright © Allyn and Bacon 2006 Types of Consequences Reinforcement Positive Negative (Add) (Remove) Apply reward to increase behavior Remove aversive stimulus to increase behavior (e.g., Getting A’s for studying hard) (e.g., Advil relieves headache) Punishment Apply negative consequence to decrease behavior (e.g., Spanking) Remove desirable stimulus to decrease behavior (e.g., Time Out) 22 Copyright © Allyn and Bacon 2006 Four Kinds of Consequences GOAL STIMULUS Increase Behavior Decrease Behavior Positive (Add) Negative (Subtract) Positive Reinforcement Negative Reinforcement Bonus for working hard Aspirin relieving headache leads to more hard work leads to more aspirin use Positive Punishment Positive Punishment Getting speeding ticket leads to less speeding Missing dinner leads to less staying out late 23 Copyright © Allyn and Bacon 2006 Class Demonstration Establishing a behavior using operant conditioning • Select a target behavior; be very specific • Using shaping reinforcing successive approximations of the behavior • Be careful to reinforce only the target behavior 24 Copyright © Allyn and Bacon 2006 Types of Reinforcers Primary reinforcers – Reinforcers, such as food and sex, that have an innate basis because of their biological value to an organism 25 Copyright © Allyn and Bacon 2006 Types of Reinforcers Secondary reinforcers – Stimuli, such as money or tokens, that acquire their reinforcing power by their learned association with primary reinforcers (also called conditioned reinforcers) 26 Copyright © Allyn and Bacon 2006 Schedules of Reinforcement Continuous reinforcement – Reinforcement schedule in which all correct responses are reinforced Partial reinforcement – Reinforcement schedule in which some, but not all, correct responses are reinforced (also called intermittent reinforcement) 27 Copyright © Allyn and Bacon 2006 Schedules of Reinforcement Ratio schedules – Provide reward after a certain number of responses Interval schedules – Provide reward after a certain time interval Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Variable Interval (VI) 28 Copyright © Allyn and Bacon 2006 Schedules of Reinforcement Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Rewards appear after a certain set number of responses e.g. factory workers getting paid after every 10 cases of product are completed Variable Interval (VI) 29 Copyright © Allyn and Bacon 2006 Schedules of Reinforcement Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Rewards appear after a certain number of responses, but that number varies from trial to trial e.g. slot machine payoffs Variable Interval (VI) 30 Copyright © Allyn and Bacon 2006 Schedules of Reinforcement Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Variable Interval (VI) Rewards appear after a certain fixed amount of time, regardless of number of responses e.g. weekly or monthly paychecks 31 Copyright © Allyn and Bacon 2006 Schedules of Reinforcement Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Variable Interval (VI) Rewards appear after a certain amount of time, but that amount varies from trial to trial e.g. random visits from the boss who delivers praise 32 Copyright © Allyn and Bacon 2006 Contingencies of Reinforcement Extinction – In operant conditioning, a process by which a response that has been learned is weakened by the absence or removal of reinforcement How does this differ from extinction in classical conditioning? 33 Copyright © Allyn and Bacon 2006 Punishment Punishment – An aversive stimulus which diminishes the strength of the response it follows How does this differ from negative reinforcement? 34 Copyright © Allyn and Bacon 2006 Punishment vs. Negative Reinforcement Negative Reinforcement Response Consequence Loud Noise Press Lever Loud Noise Removed Press Lever Loud Noise Applied Punishment No Noise 35 Copyright © Allyn and Bacon 2006 Types of Punishment Positive punishment – The application of an aversive stimulus after a response Negative punishment – The removal of an attractive stimulus after a response 36 Copyright © Allyn and Bacon 2006 Problems of Punishment Power usually disappears when threat of punishment is removed Punishment Often triggers aggression May inhibit learning new and better responses Is often applied unequally When does punishment work? 37 Copyright © Allyn and Bacon 2006 Alternatives to Punishment Extinction Reinforcing preferred activities Premack principle Prompting and shaping 38 Copyright © Allyn and Bacon 2006 Operant and Classical Conditioning Compared Classical conditioning involves the association of two stimuli (UCS + CS) before the response or behavior Operant conditioning involves a reinforcing (reward) or punishing stimulus after a response or behavior 39 Copyright © Allyn and Bacon 2006 Using Classical and Operant Conditioning to Initiate and Sustain Behavior Change Classical Conditioning connects command with behavior • UCS = tug on leash or pressure on hind legs • UCR = dog sits • CS = command (i.e., “Rocky sit”) • CR = dog sits Operant conditioning behavior is repeated • Give praise or food reward following CR • Use intermittent reinforcement to prevent extinction 40 Copyright © Allyn and Bacon 2006 Cognitive Learning Models 41 Copyright © Allyn and Bacon 2006 Kohler: Insight Learning Wolfgang Kohler Disenchanted with behaviorists explanation for learning Believed that cognition, or mental processes must be essential to learning Observational studies of chimpanzees 42 Copyright © Allyn and Bacon 2006 Insight Learning Problem – bananas hung outside of chimp’s reach Initial solutions Pile up boxes and climb on top Use sticks to knock the fruit down 43 Copyright © Allyn and Bacon 2006 Insight Learning Insight learning solve complex problems by combining simpler, previously learned responses Problem-solving occurs through sudden reorganization of perceptions Placed bananas higher up – neither previously learned solutions sufficient to get the fruit 44 Copyright © Allyn and Bacon 2006 Insight Learning When unable to reach the fruit First – threw the sticks away and kicked the wall Later, piled up the boxes, grabbed the stick, climbed on the boxes and knocked the fruit down with the stick Cannot be explained through either operant or classical conditioning alone 45 Copyright © Allyn and Bacon 2006 Kohler’s Chimps 46 Copyright © Allyn and Bacon 2006 Tolman: Cognitive Maps Cognitive maps Mental representations or images that help organisms navigate through the world Reinforcement has a greater impact on performance than on learning i.e., reinforcement serves to motivate the animal to demonstrate what it has learned 47 Copyright © Allyn and Bacon 2006 Diagram of a Tolman Maze 48 Copyright © Allyn and Bacon 2006 Cognitive Maps Three groups of rats 1) No reinforcement 2) Reinforced on every trial 3) No reinforcement for first ten trials; reinforced on all subsequent trials 49 Copyright © Allyn and Bacon 2006 Error Curve by Day and Food Deprivation 50 Copyright © Allyn and Bacon 2006 Maze Learning Food/ Goal Box Start A B 51 Copyright © Allyn and Bacon 2006 Cognitive Maps Tolman hypothesized that the rats developed cognitive maps of the maze i.e., Visual/spatial Image or representation of physical space that is used to navigate through the environment Demonstrated latent learning – learning that takes place in the absence of reinforcement reinforcement necessary to demonstrate acquisition 52 Copyright © Allyn and Bacon 2006 Bandura: Social Learning Theory Observational Learning Acquisition of behaviors that results from observation rather than direct experience E.g., Children learn do cartwheels and handstands Learn what clothes to wear to fit in (e.g., midriffs; low-riser jeans) Learn aggressive behavior 53 Copyright © Allyn and Bacon 2006 Social Learning Theory Modeling – imitation and reproduction of behaviors of models Model must be salient (i.e., are attractive, have high status, and are similar to observer) Parents, peers, siblings, celebrities 54 Copyright © Allyn and Bacon 2006 Social Learning Theory Vicarious reinforcement Learn about the consequences of a behavior by observing a model engage in the behavior and experience consequences Outcome Expectancies Learned association between a specific behavior and a specific consequence OR Belief about the consequences of our behavior 55 Copyright © Allyn and Bacon 2006 Social Learning Theory Outcome expectancies Alcohol makes me relaxed and sociable Wearing brown polyester will make me a social outcast If I study for the exam, I will get a good grade If I eat those cookies, I will feel good Having sex without a condom will result in enhanced pleasure 56 Copyright © Allyn and Bacon 2006 Social Learning Theory Positive outcome expectancies Belief that the behavior will result in reinforcing or rewarding outcomes Negative outcome expectancies Belief that the behavior will result in punishing or negative outcomes 57 Copyright © Allyn and Bacon 2006 Social Learning Theory Expectancies influence subsequent behavior Positive expectancy (i.e., belief that behavior results in reinforcing outcomes) engage in or repeat behavior Negative expectancy (i.e., belief that behavior results in punishing outcomes) avoid or discontinue behavior 58 Copyright © Allyn and Bacon 2006 Aggressive Behavior Children observed a model behave aggressively toward the BOBO doll Were more likely to behave aggressively when given the opportunity to play with the BOBO doll Especially when the model was reinforced for his/her aggressive behavior 59 Copyright © Allyn and Bacon 2006