Learning

1. Learning Chapter 8, Meyers

2. Learning • Learning: A relatively permanent change of an organism’s behavior due to experience. • learning is inferred from a change in behavior/performance • learning results in an inferred change in memory • learning is the result of experience • learning is relatively permanent • Associative Learning: learning that certain events occur together. • Observational Learning: we learn from others’ experiences and examples.

3. Associative Learning • Conditioning: the process of learning associations. • Classical conditioning: we learn to associate two stimuli and to anticipate events.

4. Associative Learning (cont’d) • Operant Conditioning: we learn to associate our response (behavior) and its consequence and, as a result, to repeat acts followed by good results and to avoid acts followed by bad results.

5. Behaviorism • Coined by John B. Watson. Also supported by Ivan Pavlov. • The perspective that psychology: • Should be an objective science • Study behavior without reference to mental processes. • Most research psychologists believe in the first statement but do not agree with the second.

6. Ivan Pavlov • Ivan Pavlov (1849-1936) • Russian physician/neurophysiologist • Studied digestive secretions • His work gave rise to understanding classical conditioning. • Won the Nobel prize in 1904 • Contiguity Model: believed in a temporal association between two events that occur closely together in time. The more closely in time two events occurred, the more likely they were to become associated.

7. Pavlov’s Experiment

8. Classical Conditioning Definitions • US (unconditioned stimulus): a stimulus that naturally & unconditionally triggers a response. • UR (unconditioned response): an unlearned naturally occurring response to the US). • US = food UR = salivation • NS (Neutral Stimulus) does not elicit a UR from the subject • CS (Conditioned stimulus): originally the NS, but after associating the NS with the US, it becomes a trigger for the CR (conditioned response). • CR (Conditioned response):a learned response to the CS after conditioning has occurred.

9. Practice US : hot water UR: jumping back NS: toilet flush CS: toilet flush CR: jumping back to flush alone • Every time someone flushes a toilet in the apartment building, the shower becomes very hot and causes the person to jump back. Over time, the person begins to jump back automatically after hearing the flush, before the water temperature changes. Identify the following: • US, UR, NS, CS, CR

10. Classical Conditioning (cont’d) • Acquisition: in classical conditioning, when NS is paired and elicits a CR • Extinction: the diminishing of a conditioned response (CR). • In classical conditioning, repeatedly presenting the CS without the UCS leads to the return of the NS. • Spontaneous Recovery: occurs after extinction, without training, the CS(NS) again elicits the CR temporarily. • Generalization: stimuli similar to the CS also elicit the CR without training. • Discrimination: the ability to tell the difference between stimuli so that only the CS elicits the CR.

11. Classical Conditioning Learning Curve

12. Higher-Order Conditioning • A well learned CS is paired with another NS to produce a conditioned response (CR) to the new NS.

13. Classical Conditioning (cont’d) • Delayed Conditioning: NS is presented just before the US, with a brief overlap between the two • Ex - a bell begins to ring and continues to ring until food is presented. • Generally produces the strongest conditioning • Trace Conditioning: when the NS is presented & then disappears just before the US appears. • ex - a bell begins ringing and ends just before the food is presented. • Produces moderately strong conditioning

14. Classical Conditioning (cont’d) • Simultaneous Conditioning: occurs when the US and NS are paired together at the same time. • ex - the bell begins to ring at the same time the food is presented. Both begin, continue, and end at the same time. • Produces weak conditioning • Backward Conditioning: the US comes before the NS. • ex - the food is presented, then the bell rings. • Produces no conditioning except in rare cases

15. The Case of Little Albert • Aversive Conditioning: learning that involves an unpleasant of harmful unconditioned stimulus • Also known as counterconditioning • John B. Watson & Rosalie Raynorstudied children’s behaviors in the 1920s. • Conditioned 9 month old Little Albert to fear a rat. His fear generalized to other animals as well. • Although unethical, this study demonstrated bow phobias or other human emotions might develop through classical conditioning. John Watson - Little Albert - YouTube

16. Biological Factors • Conditioned Taste Aversion: an intense dislike & avoidance of a food because of its association with an unpleasant or painful stimulus through backward conditioning. • Preparedness: through evolution, animals are biologically disposed to easily learn behaviors related to their survival & that behaviors contrary to an animal’s natural tendencies are learned slowly or not at all. • Garcia Effect: when rates were exposed to a tastes (NS) and then exposed them to radiation or drugs (US) that led to nausea and vomiting (CR). The rats developed aversions for those tastes, even if they did not get sick for hours after the initial exposure.

17. Nausea Conditioning in Cancer Patients

18. The Contingency Model • Cognitivist Robert Rescorla challenged Pavlov’s contiguity model. • The contingency model states that the CS tells the organism that the US will follow. • Blocking Effect: another challenge to Pavlov’s model. • rats that were classically conditioned to fear (CR) the sound of a tone (CS) using electric shock (US) could not be conditioned to also fear a light alone (after paired with the tone). • Since they already associated the tone with the impending electric shock, the light alone offered no new information, so the conditioning effect of the light was blocked.

19. Operant Conditioning • Operant Conditioning: learning in which behavior is strengthened if followed by a reinforce or diminished if followed by a punisher. • Respondent Behavior: behavior that occurs as an automatic response to some stimulus. • Term Skinner used for behavior learned through classical conditioning. • Operant Behavior: behavior that operates on the environment, producing consequences.

20. Instrumental Learning • Instrumental Learning: a form of associative learning in which a behavior becomes more or less probable depending on its consequences. • E.L. Thorndike: research with hungry cats using fish as a reward to entice cats to find their way out of a puzzle box. • The cats’ behavior tended to improve with successive trials, illustrating Thorndike’s Law of Effect that rewarded behavior is likely to recur.

21. B.F. Skinner (1904-1990) • Skinner termed Thorndike’s instrumental learning – operant conditioning because subjects operate on their own environment in order to produce desired outcomes. • Operant Chamber (Skinner Box): contained a bar or key that an animal could manipulate to obtain food or water reinforcer with attached devices in record the animal’s rate of bar pressing or key pecking. • Using the Skinner box and similar devices, behaviorists have shown that extinction, stimulus generalization, and stimulus discrimination occur in operant as well as in classical conditioning. • Developed four different training procedures working with rats, pigeons and other animals.

22. The Skinner Box Also known as the OPERANT CHAMBER

23. Positive Reinforcement • Reinforcer: any event that strengthens the behavior that follows. • Positive Reinforcement (reward training): • increasing behaviors by presenting positive rewards such as food. • Premack Principle: a more probable behavior can be used as a reinforcer for a less probable one.

24. Negative Reinforcement • Negative Reinforcement: increases behaviors by stopping or reducing the aversive stimulus • Negative Reinforcer: any stimulus that, when REMOVED after a response, strengthens the response.

25. Negative Reinforcement (cont’d) • Two types of negative reinforcement: • Avoidance behavior takes away the unpleasant stimulus before it begins • Escape behavior takes away the unpleasant stimulus after it has already started. • Learned Helplessness: feelings of futility & passive resignation that result from the inability to avoid repeated aversive events. • Later, even if it becomes possible to avoid or escape the aversive stimuli, it is unlikely that the learner will respond.

27. Punishment • In punishment, a learner’s response is followed by an aversive consequence which is unwanted, so the learner stops exhibiting the behavior. • Punishment should beimmediateso that the consequence is associated with the misbehavior, strong enough to stop the undesirable behavior, and consistent. • Punishment should not be overused. • It does not teach the learner what should be done • It suppresses rather than extinguishes behavior • It may evoke hostility or passivity.

29. Omission Training • Omission Training: A response by a learner is followed by taking away something of value from the learner. • By changing his/her behavior, the learner can get back the positive reinforcer. • ex: Time-out • Key to success – knowing exactly what is rewarding and what isn’t for each individual.

31. Reinforcers • Primary Reinforcer: something that is biologically important, so it is rewarding, such as food & drink. • Secondary (Conditioned) Reinforcer: some that is neutral that when associated with a primary reiforcer, becomes rewarding such as gold stars, money, & tokens. • Generalized Reinforcer: a secondary reinforcer that can be associated with a number of different primary reinforcers, such as money, which can buy food. • Token Economy: operant training system used extensively in institutions (mental hospitals, jails) where tokens (secondary reinforcers) are used to increase a list of acceptable behaviors. Learner accumulates tokens & then exchanges them for privileges.

32. Teaching New Behaviors • Shaping: procedure in which reinforcers guide behavior toward closer & closer approximations of the desired behavior. • Chaining: used to establish a specific sequence of behaviors by initially positively reinforcing each behavior in a desired sequence & then later rewarding only the completed sequence. • Often used to teach animals a complex series of behaviors • In general, reinforcement or punishment tha occurs immediately after a behavior has a stronger effect than when it is delayed.

33. Reinforcement Schedules • Continuous Reinforcement: reinforcing the desired response every time it occurs. • Problem: not reinforcing the behavior even once or twice could result in the extinction of the behavior. • Partial Reinforcement (intermittent schedule): reinforcing the behavior only some of the time. • Results in slower acquisition of the behavior but greater resistance to extinction. • Fixed Ratio schedule: reinforces only after a fixed number of responses. The learner will pause briefly after a reinforces & then will return to a high rate of responding.

34. Reinforcement Schedules (cont’d) • Variable Ratio Schedule: reinforces a behavior after an unpredictable number of responses. Ex. Slot machines – gamblers will pull the level hundreds of times as the anticipation fo the next reward gets stronger. • Fixed Interval Schedule: reinforces behaviors only after a specified time has elapsed. Results in lots of behavior as the time for reinforcement approaches, but little behavior until the next time for reinforcement approaches. Ex. Cramming for an exam. • Variable Interval: reinforces a response at unpredictable time intervals Ex. Studying every night because the teacher gives pop quizes.

36. More on Skinner • Skinner accounted fore the development of superstitious behaviors in partial reinforcement schedules he performed with pigeons. • If food pellets were delivered when a pigeon was performing some idiosyncratic behavior, the pigeon would tend to repeat the behavior to get more food. • If food pellets were again delivered when the pigeon repeated this behavior, the pigeon would repeat the behavior over and over, resulting in the development of superstitious behavior. • There is a correlation between the idiosyncratic behavior and the food, but there is NO causal relationship between the two. • Humans – lucky numbers or lucky jeans, or even lucky charms.

37. More on Skinner (cont’d) • Skinner emphasized external controls on behavior. • Encouraged the use of operant conditioning principles at school, work, & at home. • He was criticized for dehumanizing people by neglecting their personal freedom & by seeking to control their actions. • He was criticized for deemphasizing the importance of cognition and biological constraints on learning, particularly among humans.

38. Latent Learning • Latent Learning: learning without rewards • Maze experiment with rats: • The first group of rats were given a reward each time they navigated a maze correctly. This trial was repeated over 10 days. • The second group were not given a reward for going through the maze – they made significantly more errors than the rats in the rewarded group. • On the 11th day both groups were rewarded for completing the maze correctly. • On the 12th day the second group navigated the maze as well as the first group demonstrating latent learning. • It was hypothesized that the rats had made a mental picture of the maze during the previous unrewarded trials – when they were rewarded, they were motivated to improve.

39. Latent Learning

40. Instinctive Drift • Sometimes operantly conditioned animals fail to behave as expected. • Sometimes Skinner box trained rats reverted to scratching and biting the lever. • Instinctive Drift: a conditioned response that drifts back toward the natural or instinctive behavior of the organism. • For example, wild animal trainers must be vigilant after training animals because the animals may revert to dangerous behaviors.

42. Observational Learning • Observational Learning: learning by observation • Modeling: the process of observing and imitating a specific behavior. • Mirror Neurons: frontal lobe neurons that fire when performing certain actions or observing another doing so. • These neurons transform the sight of someone else’s actions into the motor program you would use to do the same thing • may enable imitation, language training, & • empathy

43. Albert Bandura Pioneer in research on observational learning Social Learning Theory: proposed that direct reinforcement could not account for all types of learning. There are three core concepts to social learning theory: -- people can learn through observation. -- internal mental states are an essential part of this process. -- just because something has been learned, it does not mean that it will result in a change in behavior. Asserted that Intrinsic Motivation was another important factor to learning.

44. The Modeling Process Attention Retention:The ability to store information Reproduction:perform the observed behavior. Further practice leads to improvement and skill advancement. Motivation: must be motivated to imitate the behavior that has been modeled Reinforcers play an important role in motivation. While experiencing these motivators can be highly effective, so can observing these reinforcers with individuals exhibiting similar behavior. Ex: if you see another student rewarded with extra credit for being to class on time, you might start to show up a few minutes early each day. Prosocial Modeling: positive, constructive, helpful behavior. Children tend to imitate what a model does & says, whether the behavior is prosocial or antisocial. If the model’s actions are inconsistent, they may model the hypocracy they see.

45. The BoBo Experiment Bandura demonstrated that children learn and imitate behaviors they have observed in other people. The children in Bandura’s studies observed an adult acting violently toward a Bobo doll. When the children were later allowed to play in a room with the Bobo doll, they began to imitate the aggressive actions they had previously observed. It was also found that boys engaged in twice as many acts of agression to the BoBo doll than girls & that boys were more prone to imitate physical acts of violence where girls tended to imitate verbal aggression. Bandura - bobo doll experiment - YouTube

46. BoBo Experiment Criticisms A lab setting experiment may not be indicative of what takes place in reality. Selection bias: All participants were drawn from a narrow pool of students who share the same racial and socioeconomic background. Was there a long-term impact? Acting violently toward a doll is a lot different that displaying aggression or violence against another. Unethical study: Manipulating children into behaving aggressively was essentially teaching children to be violent.