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Chapter 8

Chapter 8. Learning. Learning: A relatively permanent change in behavior due to experience or practice. What words are important in that definition? Relatively permanent Change in behavior Practice. How Do We Learn. How Do We Learn Associative Learning

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Chapter 8

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  1. Chapter 8 Learning

  2. Learning:A relatively permanent change in behavior due to experience or practice • What words are important in that definition? • Relatively permanent • Change in behavior • Practice

  3. How Do We Learn • How Do We Learn • Associative Learning • Learning that certain events occur together. The events may be two stimuli (as in classical conditioning) or a response and it’s consequence (as in operant conditioning) • Classical Conditioning (Pavlov) • Operant Conditioning (Skinner)

  4. Classical Conditioning • Classical Conditioning (A.K.A. Pavlovian or respondent conditioning) A type of learning in which an organism comes to associated two previously unrelated stimuli. A neutral stimulus that signals an unconditioned stimulus begins to produce a response that anticipates and prepares for the unconditioned stimulus

  5. Neutral Stimulus Unconditioned Stimulus Signals Unconditioned Stimulus Produces a response

  6. Classical Conditioning • Behaviorism • A perspective of psychology associated with John B. Watson, it is the view that psychology should be an objective science that studies only observable events

  7. Pavlov’s Experiment • Ivan Pavlov:(1849-1906) Pavlov was a Russian physiologist whose pioneering studies of the digestive system led to decades of research to identify the principles of classical conditioning

  8. Pavlov’s Experiment • Labeling the parts of classical conditioning • Unconditioned Response:A simple unlearned response. A reflex Examples:

  9. Pavlov’s Experiment • Labeling the parts of classical conditioning • Unconditioned Stimulus: A stimulus that triggers a response reflexively or automatically Examples:

  10. Pavlov’s Experiment • Labeling the parts of classical conditioning • Neutral Stimulus: Does not elicit (bring about) the unconditioned response

  11. Pavlov’s Experiment When has conditioning occurred? Conditioning has occurred when the neutral stimulus ALONE elicits (causes) the unconditioned response

  12. Pavlov’s Experiment • Labeling the parts of classical conditioning • Conditioned Stimulus: The conditioned stimulus is the previously neutral stimulus that, through conditioning (learning) gains the power to cause the response

  13. Pavlov’s Experiment • Labeling the parts of classical conditioning • Conditioned Response: The conditioned response is the previously unconditioned response. It is elicited by (caused by) the conditioned stimulus.

  14. Pavlov’s Experiment

  15. Pavlov’s Experiment

  16. Practice UCS UCR (Before Conditioning) NS + UCS UCR (Acquisition Phase) CS CR (After Conditioning)

  17. Pavlov’s Experiment • Forward Pairing • The CS is presented BEFORE the UCS • Backward Pairing • The CS is presented AFTER the UCS (due to the fact that classical conditioning usually prepares the organism for an event, backward conditioning is generally ineffective) • Simultaneous Pairing • The CS and UCS occur at exact the same time

  18. Acquisition • Acquisition • The initial stage in classical conditioning; the phase when the organism begins to associate the neutral stimulus with the unconditioned stimulus so that eventually the neutral stimulus comes to elicit a conditioned response • Research reveals that acquisition occurs best when the time between the NS and the UCS is about ½ second • Acquisition will occur more readily between cues that insure our survival (Examples?)

  19. Extinction and Spontaneous Recovery • Extinction • After repeated presentation of the conditioned stimulus (CS) without the unconditioned stimulus (UCS) the conditioned response (CR) fades away and eventually stops.

  20. Extinction and Spontaneous Recovery • Extinction • Reconditioning: if the conditioned stimulus (CS) and the unconditioned stimulus (UCS) are paired after extinction has occurred, the conditioned response (CR) return to its original strength very quickly, often after one or two trial

  21. Extinction and Spontaneous Recovery • Extinction • Reconditioning: if the CS and the UCS are paired after extinction has occurred, the CR returns to its original strength very quickly, often after one or two trials (What does this tell you about extinction?)

  22. Extinction and Spontaneous Recovery • Spontaneous Recovery: After extinction, and a lapse of time, the conditioned response reappears The two factors needed for spontaneous recovery to occur are: 1. extinction 2. rest period (lapse of time)

  23. Extinction and Spontaneous Recovery • Stimulus Generalization:The organism responds NOT ONLY to the conditioned stimulus (CS) but also to similar stimuli

  24. Extinction and Spontaneous Recovery • Stimulus Generalization Example: (Little Albert)

  25. Discrimination • Discrimination : • In classical conditioning when an organism responds differently to different stimuli

  26. Cognitive Processes • Rescorla believes that whether or not a conditioned response is learned is dependent on the following factors: • Timing • Predictability • Signal Strength • Attention • Second-Order Conditioning (Higher Order Conditioning) • Biopreparedness (Garcia)

  27. Cognitive Processes • Timing: • Forward Conditioning is better than either backward or simultaneous conditioning. • Furthermore research shows that forward conditioning works best when the delay between the CS and the UCS is only a half a second to full second

  28. Cognitive Processes • Predictability • Classical Conditioning occurs most quickly when the Conditioned Stimulus (CS) ALWAYS and ONLY signals the Unconditioned Stimulus (UCS)

  29. Cognitive Processes • Signal Strength • A Conditioned Response (CR) will be greater and will be established more quickly if the Unconditioned Stimulus (UCS) is strong and distinct. This is also true if the Conditioned Stimulus (CS) is strong.

  30. Cognitive Processes • Attention: • The stimulus that is being most closely attended to, and most fully perceived at that moment is the stimulus that is most likely to become the Conditioned Stimulus (CS)

  31. Cognitive Processes • Second-Order Conditioning (Higher Order Conditioning) A conditioned stimulus functions as if it were an unconditioned stimulus. In other words, an already established Conditioned Stimulus (CS) can serve as an Unconditioned Stimulus.

  32. Cognitive Processes • Biopreparedness (Garcia): Being biologically prepared or genetically tuned to develop certain conditioned associations • Example: Taste Aversions (a.k.a. bait shyness)

  33. Recognizing Basic Processes in Classical Conditioning • Lucy has flunked algebra twice. Now whenever she sees any kind of math book, she begins to get that same old sick feeling in the pit of her stomach. • 2. Little Suzy is experiencing her first thunderstorm. A bolt of lightning flashes across the sky, but this doesn’t bother her; she thinks it’s pretty. A second later, however, she just about jumps out of her skin when a tremendous crash of thunder shakes the room.

  34. Recognizing Basic Processes in Classical Conditioning 3. Otto has gotten A’s on all of his quizzes in history, so he likes Professor Olden quite a bit. But he’s not too crazy about professor Datum, because Otto’s received nothing but C’s and D’s in his research methods class. 4. Glenda tried sushi for the first time when she visited her cousin in San Francisco, and she love it. Back home in Kansas City she eagerly searched until she found a restaurant that served sushi, but the fish wasn’t fresh, so she didn’t like it much. On a visit to St. Louis she tried again, but she was disappointed once more. Glenda no longer gets excited by the prospect of eating sushi, unless it’s San Francisco sushi, which still makes her mouth water.

  35. Recognizing Basic Processes in Classical Conditioning 5.On his first day at work at the Joy Ice Cream Shop, Arnold helped himself and overdid it. He got sick and swore he’d never eat ice cream again. True to his word, he stayed off the stuff for the rest of the summer, though he continued working at the shop. For a while it was hard, because the sight and smell of the ice cream made him feel nauseous, but eventually those feelings faded. The following summer Arnold decided to visit his old employer, but as soon as he walked in the door, he felt so sick he had to turn around and leave immediately. 6. Little Timmy used to get so excited whenever Grandpa would come to visit, because Grandpa always brought Timmy some neat new toy. As Grandpa got older, however, he became forgetful. He no longer brings toys when he visits. Now Grandpa’s visits don’t excite Timmy as much.

  36. Biological Predispositions The early behaviorists view that any natural response could be conditioned to any neutral stimulus has given way to the understanding that each species is biologically prepared to learn associations that enhance its survival. Therefore humans more easily learn to fear snakes and spiders than to fear flowers. Rats develop aversions to tastes but not to sights or sounds

  37. Biological Predispositions • Taste Aversion • Taste Aversion is unusual because • it often only takes a single trial • The Unconditioned Stimulus (UCS) does not need to immediately follow the Conditioned Stimulus (CS) for learning to occur We seemed primed for this learning because from an evolutionary perspective it ensures our survival.

  38. Pavlov’s Legacy • Pavlov taught us that principles of learning apply across species and that classical conditioning is one way that virtually all organisms learn to adapt to their environment. Pavlov also demonstrated that significant psychological phenomena can be studied objectively. Finally, Pavlov taught us that conditioning principles have important applications such as how to treat fear.

  39. Applications of Classical Conditioning • Learned Immune Response: Classical conditioning has been used to help simulate the effects of drugs that suppress the immune system drugs suppression of immune system UCS UCR NS + UCS UCR CS CR smell smell Suppression of immune system

  40. Applications of Classical Conditioning • Phobias: Through classical conditioning and then Stimulus Generalization, a person may learn a phobia

  41. Applications of Classical Conditioning • Predator Control: Classical Conditioning (specifically taste aversion) has been used to alleviate the problem of animal predators eating/killing ranchers’ sheep Lithium chloride nausea UCS UCR NS + UCS UCR CS CR sheep nausea sheep

  42. Operant Conditioning Operant Conditioning vs. Classical Conditioning 1. Bhvr is voluntary 1. Bhvr. is involuntary 2. Learns to associate 2. Learns to associate a bhvr w/the consequence 2 stimuli 3. Organism is active 3. Organism is passive 4. R+ comes AFTER 4. R+ comes BEFORE

  43. Operant Conditioning • Operant Conditioning: The basic learning process (proposed by B.F. Skinner) that involves changing the probability of a response by manipulating the consequences of that response • Respondent Behavior: Behavior that occurs as an automatic response to some stimulus (Skinner’s term for behavior learned through classical conditioning) • Operant Behavior:Behavior that operated on the environment, producing consequences

  44. Operant Conditioning • Laws of Effect (E.L. Thorndike): • Positive Law of Effect: If a behavior is followed by a satisfying state of affairs, the likelihood of the behavior occurring again increases. • Negative Law of Effect: If a behavior is followed by an unpleasant state of affairs, the likelihood of the behavior occurring again decreases

  45. Operant Conditioning • Operant Chamber (Skinner box): An apparatus used by Skinner (developed in the 1930s) to study behavior. Generally, it provides a relatively small and plain environment that blocks out extraneous stimuli and measures behavior

  46. Shaping • Shaping: Reinforcing behaviors that move closer and closer to the target behavior When is shaping used? Shaping is used when trying to teach a complex or difficult task Human example?

  47. Types of Reinforcers • Reinforcement: Reinforcement ALWAYS increases the likelihood of a behavior

  48. Types of Reinforcers • Positive Reinforcement:Something pleasant is added in order to increase a response http://www.youtube.com/watch?v=guroaQRFsX4

  49. Types of Reinforcers • Negative Reinforcement: Something unpleasant is removed in order to increase a response …

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