Unit 6 Learning

1. Unit 6Learning 11/13/13

2. How do we learn? • Brainstorm, what are some ways we learn new information? • Do we learn similarly to any other animals? • Does everybody learn the same way?

3. How we Learn • Learning: A relatively permanent change in an organism’s behavior due to experience. • Habituation: an organism’s decreasing response to a stimulus with repeated exposure to it. • Associative learning: Learning that certain events occur together. The events maybe two stimuli or a response and its consequences

4. Learning and Conditioning • Learning - A relatively permanent change in behavior due to experiences • Conditioning – The acquisition of specific patterns of behavior in the presence of well-defined stimuli • Classical and Operant

5. Classical Conditioning • Stimulus = cause • Response = effect Video Ivan Pavlov (1849–1936)

6. Elements of Classical Conditioning • Neutral Stimulus (NS) • Unconditioned Stimulus (US) • Unconditioned Response (UR) • Conditioned Stimulus (CS) • Conditioned Response (CR)

7. Neutral Stimulus—Bell • Does not normally cause a response or reflex action by itself • a bell ringing • a color • a furry object

8. Unconditioned Stimulus—Food • Always cause a reflex action • food • blast of air • noise

9. Unconditioned Response - Salivation • A response to an unconditioned stimulus—naturally occurring reflex • Salivation at smell of food • Eye blinks at blast of air • Startle reaction in babies

10. Conditioned Stimulus • The learned (once neutral) stimulus • The tone of the bell causes salivation • Will eventually elicit the unconditioned response by itself

11. Conditioned Response • The original unconditioned response becomes conditioned after it has been elicited by the neutral stimulus • Salivation because of the bell tone

15. Classical Conditioning in Humans • Watson and Little Albert • Identify the: • Neutral Stimulus • Unconditioned Stimulus • Unconditioned Response • Conditioned Stimulus • Conditioned Response • Is this Ethical?

17. Identify the: • Neutral Stimulus (NS) • Unconditioned Stimulus (US) • Unconditioned Response (UR) • Conditioned Stimulus (CS) • Conditioned Response (CR)

18. Classical Conditioning • Acquisition: in classical conditioning, the stage when links a neutral stimulus and an unconditioned stimulus are linked so that the neutral stimulus begins triggering the conditioned response. • Higher-order conditioning: a procedure in which the conditioned stimulus in one conditioning experience is paired with a new neutral stimulus, creating a second (often weaker) conditioned stimulus. • For example, an animal that has learned that a tone predicts food might then learn that a light predicts the tone and begin responding to the light alone. (Also called second-order conditioning.)

19. Extinction: the diminishing of a conditioned response; occurs in classical conditioning when an unconditioned stimulus (US) does not follow a conditioned stimulus (CS); occurs in operant conditioning when a response is no longer reinforced. • Spontaneous recovery: the reappearance, after a pause, of an extinguished conditioned response.

20. Generalization: the tendency, once a response has been conditioned, for stimuli similar to the conditioned stimulus to elicit similar responses. • Discrimination: in classical conditioning, the learned ability to distinguish between a conditioned stimulus and stimuli that do not signal an unconditioned stimulus.

21. Cognitive Processes • Early behaviorists believed that learned behaviors of various animals could be reduced to mindless mechanisms. • However, later behaviorists suggested that animals learn the predictability of a stimulus, meaning they learn expectancy or awareness of a stimulus (Rescorla, 1988). • Learned Helplessness • Not just the conditioning, the thought influences behavior as well

22. Biological Predispositions • Pavlov and Watson believed that laws of learning were similar for all animals. Therefore, a pigeon and a person do not differ in their learning. • However, behaviorists later suggested that learning is constrained by an animal’s biology. • Each species’ predispositions prepare it to learn the associations that enhance its survival.

23. Biological Predispositions 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). Taste Aversion Courtesy of John Garcia John Garcia

24. Biological Predispositions Even humans can develop classically to conditioned nausea.

26. Operant Conditioning • Classical Conditioning involves respondent behavior (automatic actions) • Operant conditioning reinforces desired behavior and discourages undesired behavior. • Operant behavior: Behavior that operates (has an effect) on the environment to produce consequences • Classical conditioning=no control • Operant conditioning= control of behavior and consequences

27. Operant Conditioning • Law of effect: rewarded behavior is likely to recur (Edward Thorndike) • Skinner used the Law of Effect to develop principles of behavior control. • Operant chamber/Skinners box: box containing a bar or key that an animal can use to obtain a food or water reinforcer; attached devices record rate of bar or key pressing

29. Shaping: reinforcers guide behavior toward desired behavior with successive approximations • Discriminative Stimulus: elicits response after association with reinforcement (remember discrimination vs. generalization)

30. Reinforcer: in operant conditioning, any event that strengthens the behavior it follows. • Positive Reinforcement: increasing behaviors by presenting positive stimuli, such as food. A positive reinforcer is any stimulus that, when presented after a response, strengthens the response. • Negative Reinforcement: increases behaviors by stopping or reducing negative stimuli, such as shock. A negative reinforcer is any stimulus that, when removed after a response, strengthens the response (Note: negative reinforcement is NOT punishment).

31. Primary reinforcer: an innately reinforcer stimulus, such as one that satisfies a biological need. • Conditioned reinforcer: a stimulus that gains its reinforcing power through its association with a primary reinforcer; also known as a secondary reinforcer.

32. Immediate and Delayed Reinforcement • Which one works better? • In rats-immediate • In humans- both will work, sometimes delayed works better. • If given the option of a small candy bar today or a big candy bar tomorrow what would you choose?

33. Reinforcement Schedules • Continuous reinforcement: Reinforcing the desired response every time it occurs. • Partial (intermittent) reinforcement: Reinforcing a response only part of the time; results in slower acquisition of a response but much greater resistance to extinction

34. Ratio Version – having to do with instances of the behavior. Ex. – Reinforce or reward the behavior after a set number or x many times that an action or behavior is demonstrated. Interval Version – having to do with the passage of time. Ex. – Reinforce the participant after a set number or x period of time that the behavior is displayed. Schedules of Reinforcement

35. 4 Basic Schedules of Reinforcement • Fixed-interval schedule • Variable-interval schedule • Fixed-ratio schedule • Variable-ratio schedule

36. Fixed-Interval Schedule • Fixed-interval schedule – A schedule in which a fixed amount of time must elapse between the previous and subsequent times that reinforcement will occur. • No response during the interval is reinforced. • The first response following the interval is reinforced. • Produces an overall low rate of responding • Ex.I get one pellet of food every 5 minutes when I press the lever

37. Fixed Interval Reinforcement

38. Variable-Interval Schedule • Variable-interval Schedule – A schedule in which a variable amount of time must elapse between the previous and subsequent times that reinforcement is available. • Produces an overall low consistent rate of responding. • Ex.– I get a pellet of food on average every 5 minutes when I press the bar.

39. Variable Interval Reinforcement

40. Fixed-Ratio Schedule • Fixed-ratio Schedule – A schedule in which reinforcement is provided after a fixed number of correct responses. • These schedules usually produce rapid rates of responding with short post-reinforcement pauses • The length of the pause is directly proportional to the number of responses required • Ex. – For every 5 bar presses, I get one pellet of food

41. An Example of Fixed Ratio Reinforcement • Every fourth instance of a smile is reinforced

42. Fixed Ratio Reinforcement

43. Variable-Ratio Schedule • Variable-ratio Schedule – A schedule in which reinforcement is provided after a variable number of correct responses. • Produce an overall high consistent rate of responding. • Ex. – On average, I press the bar 5 times for one pellet of food.

44. An Example of Variable Ratio Reinforcement • Random instances of the behavior are reinforced

45. Variable Ratio Reinforcement

48. Comparisons of Schedules of Reinforcement FORM OF REWARD INFLUENCE ON PERFORMANCE EFFECTS ON BEHAVIOR SCHEDULE Fixed interval Leads to average and irregular performance Fast extinction of behavior Reward on fixed time basis Fixed ratio Reward tied to specific number of responses Moderately fast extinction of behavior Leads quickly to very high and stable performance Variable interval Reward given after varying periods of time Leads to moderately high and stable performance Slow extinction of behavior Variable ratio Reward given for some behaviors Leads to very high performance Very slow extinction of behavior

49. When I bake cookies, I can only put one set in at a time, so after 10 minutes my first set of cookies is done. After another ten minutes, my second set of cookies is done. I get to eat a cookie after each set is done baking. After every 10 math problems that I complete, I allow myself a 5 minute break. I look over my notes every night because I never know how much time will go by before my next pop quiz. When hunting season comes around, sometimes I’ll spend all day sitting in the woods waiting to get a shot at a big buck. It’s worth it though when I get a nice 10 point. Today in Psychology class we were talking about Schedules of Reinforcement and everyone was eagerly raising their hands and participating. Miranda raised her hand a couple of times and was eventually called on. FI FR VI VI VR FI, VI, FR, or VR?

50. Punishment • While reinforcement increases behavior, punishment does the opposite • Punishment: An event that decreases the behavior that it follows. • Positive punishment: adding an aversive stimulus. (spanking) • Negative punishment: taking away desirable stimulus. (grounded)