learning

1. 4 learning

2. why study learning?If we had not been able to learn, we would have died out as a species long ago. Learning is the process that allows us to adapt to the changing conditions of the world around us. We can alter our actions until we find the behavior that leads us to survival and rewards, and we can eliminate actions that have been unsuccessful in the past. Without learning, there would be no buildings, no agriculture, no lifesaving medicines, and no human civilization.

3. Learning Objectives • LO 4.1 Learning • LO 4.2 Classical conditioning • LO 4.3 Conditioned emotional response • LO 4.4 Operant conditioning: Thorndike and Skinner • LO 4.5 Important concepts in operant conditioning • LO 4.6 Schedules of reinforcement • LO 4.7 How does punishment differ from reinforcement? • LO 4.8 Problems associated with the use of punishment • LO 4.9 Factors limiting or enhancing operant conditioning • LO 4.10 Behavioral Techniques and Behavior Modification • LO 4.11 Cognitive learning theory • LO 4.12 Observational learning • LO 4.13 Real world example of use of conditioning

4. What is Learning? LO 5.1 Learning • Learning • Relatively permanent change in behavior • Brain physically changes in response to learning • Brought about by experience or practice • Any kind of change in the way an organism behaves is learning

5. Pavlov and Classical Conditioning LO 5.2 Classical conditioning • Ivan Pavlov • Russian physiologist • Studied digestion in dogs • Dogs naturally salivate in response to food (reflex) • Pavlov’s dogs salivated in response to other stimuli as well

6. Pavlov and Classical Conditioning LO 5.2 Classical conditioning • Ivan Pavlov • Labeled classical conditioning • Learning response to a stimulus other than the original • New response does not naturally occur in response to the stimulus, is learned

7. Dr. Ivan Pavlov and students working in his laboratory. Pavlov, a Russian physiologist, was the first to study and write about the basic principles of classical conditioning.

8. Classical Conditioning Concepts LO 5.2 Classical conditioning • Unconditioned stimulus (UCS) • Naturally occurring stimulus • Leads to an involuntary response • Unconditioned: • “Unlearned” or “naturally occurring” • Unconditioned response (UCR) • Involuntary response to naturally occurring stimulus

9. Classical Conditioning Concepts LO 5.2 Classical conditioning • Conditioned stimulus (CS) • Stimulus is able to produce learned reflex response • Paired with the original unconditioned stimulus • Conditioned = “learned” • Neutral stimulus • Becomes conditioned stimulus when paired with an unconditioned stimulus

10. Classical Conditioning Concepts LO 5.2 Classical conditioning • Conditioned response (CR) • Learned reflex response to a conditioned stimulus. • Sometimes called conditioned reflex

11. Figure 5.1 Classical ConditioningBefore conditioning takes place, the sound of the metronome does not cause salivation and is a neutral stimulus, or NS. During conditioning, the sound of the metronome occurs just before the presentation of the food, the UCS. The food causes salivation, the UCR. When conditioning has occurred after several pairings of the metronome with the food, the metronome will begin to elicit a salivation response from the dog without any food. This is learning, and the sound of the metronome is now a CS and the salivation to the bell is the CR.

12. Classical Conditioning Principles LO 5.2 Classical conditioning • CS must come before UCS • CS and UCS must come very close together in time • Ideally, only several seconds apart • Neutral stimulus must be paired repeatedly with UCS before conditioning takes place • CS is usually a stimulus that is distinctive from other competing stimuli

13. Could this be you? The anxiety that many people feel while in the dentist’s office is a conditioned response, with the dentist’s chair and the smells of the office acting as conditioned stimuli.

14. Classical Conditioning Concepts LO 5.2 Classical conditioning • Stimulus generalization • Respond to a stimulus similar to original conditioned stimulus with conditioned response • Stimulus discrimination • Not making a generalized response to similar stimulus • Similar stimulus was never paired with the unconditioned stimulus

15. Classical Conditioning Concepts LO 5.2 Classical conditioning • Extinction • Disappearance/weakening of learned response • Follows removal or absence of the unconditioned stimulus (classical conditioning) • Removal of reinforcer (operant conditioning)

16. Figure 4.2 Strength of the Generalized ResponseAn example of stimulus generalization. The UCS was an electric shock and the UCR was the galvanic skin response (GSR), a measure associated with anxiety. The subjects had been conditioned originally to a CS tone (0) of a given frequency. When tested with the original tone, and with tones 1, 2, and 3 of differing frequencies, a clear generalization effect appeared. The closer the frequency of the test tone to the frequency of tone 0, the greater was the magnitude of the galvanic skin response to the tone (Hovland, 1937).

17. Classical Conditioning Concepts LO 5.2 Classical conditioning • Spontaneous recovery • Reappearance of learned response after extinction • Response usually weak and short-lived • Higher-order conditioning • Strong conditioned stimulus is paired with a neutral stimulus • Neutral stimulus to become a second conditioned stimulus

18. Figure 4.3 Extinction and Spontaneous RecoveryThis graph shows the acquisition, extinction, spontaneous recovery, and reacquisition of a conditioned salivary response. Typically, the measure of conditioning is the number of drops of saliva elicited by the CS on each trial. Note that on the day following extinction, the first presentation of the CS elicits quite a large response.

19. Figure 4.4 Higher-Order ConditioningIn Stage 1, a strong salivation response is conditioned to occur to the sound of the metronome (CS1). In Stage 2, finger snapping (CS2) is repeatedly paired with the ticking of the metronome (CS1) until the dog begins to salivate to the finger snapping alone. This is called “higher-order conditioning,” because one CS is used to create another, “higher” CS.

20. Conditioned Emotional Response LO 5.3 Conditioned emotional response • Emotional response classically conditioned to occur to learned stimuli • Examples: • Fear of dogs • Emotional reaction to seeing an attractive person, baby animals, etc. • May lead to phobias – irrational fear responses

21. Conditioned Emotional Response LO 5.3 Conditioned emotional response • Vicarious conditioning • Classical conditioning acquired by watching the reaction of another person

22. Figure 4.5 Conditioning of “Little Albert”After “Little Albert” had been conditioned to fear a white rat, he also demonstrated fear to a rabbit, a dog, and a sealskin coat (although it remains uncertain if stimulus generalization actually occurred as this fear was to a single rabbit, a single dog, etc.). Can you think of any emotional reactions you experience that might be classically conditioned emotional responses?

23. Taste Aversion LO 5.3 Conditioned emotional response • Conditioned taste aversion • Nausea or aversive response to a particular taste • Exposure to taste was followed by a aversive reaction

24. Taste Aversion LO 5.3 Conditioned emotional response • Conditioned taste aversion • Occurs after only one association • Biological preparedness • Animals learn associations with only one or few pairings • Survival value as animal could die with multiple tastings

25. Conditioned taste aversions in nature. This moth is not poisonous to birds, but the monarch butterfly whose coloring the moth imitates is quite poisonous. Birds find their food by vision and will not eat anything that resembles the monarch.

26. Why Classical Conditioning Works LO 5.3 Conditioned emotional response • Stimulus substitution • Pavlov’s explanation • Conditioned stimulus (CS) becomes substitute for unconditioned stimulus (UCS) due to close pairing of two • Cognitive perspective • Conditioning occurs because CS provides information or expectancy about UCS forthcoming

27. Operant Conditioning LO 5.4 Operant conditioning: Thorndike and Skinner • Involves voluntary behavior • Learned through the effects of pleasant and unpleasant consequences to responses

28. Operant Conditioning LO 5.4 Operant conditioning: Thorndike and Skinner • Thorndike’s Law of Effect • If a response is followed by a pleasurable consequence, it will be repeated • If followed by an unpleasant consequence, it will tend not to be repeated

29. Skinner’s Contribution LO 5.4 Operant conditioning: Thorndike and Skinner • Stressed the study of only observable, measurable behavior. • Operant conditioning • Voluntary behavior used to operate on the environment • Focus on the effects of the consequences of behavior

30. Figure 4.7 A Typical Skinner BoxThis rat is learning to press the bar in the wall of the cage in order to get food (delivered a few pellets at a time in the food trough on lower left). In some cases, the light on the top left might be turned on to indicate that pressing the bar will lead to food or to warn of an impending shock delivered by the grate on the floor of the cage.

31. Reinforcement LO 5.5 Important concepts in operant conditioning • Reinforcement • Event or stimulus following a response that increases the probability the response will occur again • Primary reinforcer • Reinforcer that meets a basic biological need • hunger, thirst, touch

32. Reinforcement LO 5.5 Important concepts in operant conditioning • Reinforcement • Secondary reinforcer • Reinforcer associated with a primary reinforcer • praise, tokens, gold stars

33. Positive and Negative Reinforcement LO 5.5 Important concepts in operant conditioning • Positive reinforcement • Pleasurable consequence follows response • Negative reinforcement • Removal of unpleasant stimulus increases response • Escape from, or avoidance of an unpleasant stimulus.

34. Table 4.1 Comparing Two Kinds of Conditioning

35. Schedules of Reinforcement LO 5.6 Schedules of reinforcement • Partial reinforcement effect • Response is reinforced after some, but not all, correct responses • Response tends to be resistant to extinction • Continuous reinforcement • Reinforcement of each and every correct response

36. Schedules of Reinforcement LO 5.6 Schedules of reinforcement • Fixed ratio schedule • Number of responses required for reinforcement is always the same • Variable interval schedule • Interval of time must pass before reinforcement becomes possible • Amount of time different for each trial or event.

37. When people go fishing, they never know how long they may have to dangle the bait in the water before snagging a fish. This is an example of a variable interval schedule of reinforcement and explains why some people, such as this father and son, are reluctant to pack up and go home.

38. Schedules of Reinforcement LO 5.6 Schedules of reinforcement • Fixed interval schedule • Interval of time that must pass before reinforcement becomes possible • Amount of time passing is always the same • Variable ratio schedule • Number of responses required for reinforcement is different for each trial or event.

39. Slot machines provide reinforcement in the form of money on a variable ratio schedule, making the use of these machines very addictive for many people. People don’t want to stop for fear the next pull of the lever will be that “magic” one that produces a jackpot.

40. Figure 4.8 Schedules of ReinforcementThese four graphs show the typical pattern of responding for both fixed and variable interval and ratio schedules of reinforcement. The responses are cumulative, which means new responses are added to those that come before, and all graphs begin after the learned pattern is well established. Slash marks mean that a reinforcement has been given. In both the fixed interval and fixed ratio graphs, there is a pause after each reinforcement as the learner briefly “rests.” The “scalloped” shape of the fixed interval curve is a typical indicator of this pause, as is the stair-step shape of the fixed ratio curve. In the variable interval and ratio schedules, no such pause occurs, because the reinforcements are unpredictable. Notice that both fixed and variable interval schedules are slower (less steep) than the two ratio schedules because of the need to respond as quickly as possible in the ratio schedules.

41. Punishment LO 5.7 How does punishment differ from reinforcement • Follows a response, making it less likely the response will happen again • Is the opposite of reinforcement • Punishment weakens responses, reinforcement strengthens responses

42. Punishment LO 5.7 How does punishment differ from reinforcement • Is the opposite of reinforcement • Punishment by application • The addition or experience of an unpleasant stimulus following a response • Punishment by removal • Removal of a pleasurable stimulus

43. This young man’s father is applying punishment by removal as he takes the car keys away from his son.

44. Table 4.3 Negative Reinforcement Versus Punishment by Removal

45. Problems with Punishment LO 5.8 What are some problems with punishment • May cause punished to avoid the punisher instead of the behavior being punished • Wrong response is learned • Can encourage lying to avoid punishment

46. Problems with Punishment LO 5.8 What are some problems with punishment • May create fear and anxiety • Emotions not conducive to learning • Hitting provides model for aggression • Behavior is being modeled by the punisher

47. How to Make Punishment More Effective LO 5.8 What are some problems with punishment • Punishment should immediately follow the behavior it is meant to punish. • Punishment should be consistent. • Punishment of the wrong behavior should be paired, whenever possible, with reinforcement of the right behavior.

48. Stimulus Control LO 5.9 How operant stimuli control behavior • Discriminative stimulus • Provides organism a cue for making a certain response in order to obtain reinforcement

49. Operant Conditioning Concepts LO 5.9 How operant stimuli control behavior • Shaping • Small steps toward goal behavior are reinforced until goal behavior is met • Successive approximations • The steps in behavior leading to a particular goal behavior

50. This dog has been trained to help its physically challenged owner. Operant conditioning principles can be used to train animals to do many useful tasks, including opening the refrigerator.