Learning and Cognitive Processes. learning. How Do We Learn? A relatively permanent change in behavior that results from experience

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1 Learning and Cognitive Processes Understanding Psychology Chapter 2 How Do We Learn? learning We learn by association. Our minds naturally connect events that occur in sequence. A relatively permanent change in behavior that results from experience 4 How Do We Learn? 2000 years ago, Aristotle suggested this law of association. Associative Learning Learning to associate one stimulus with another. Then 200 years ago Locke and Hume reiterated this law. 5 6

2 Associative Learning Learning to associate one stimulus with another. Associative Learning Learning to associate a response with a consequence. 7 8 Associative Learning Learning to associate a response with a consequence. Three Basic Types of Learning: Classical conditioning Operant conditioning Modeling 9 Classical Conditioning Classical Conditioning Ideas of classical conditioning originate from old philosophical theories. However, it was the Russian physiologist Ivan Pavlov who elucidated classical conditioning. His work provided a basis for later behaviorists like John Watson. Sovfoto Ivan Pavlov ( ) 12

3 Pavlov s Experiments Before conditioning, food (Unconditioned Stimulus, US) produces salivation (Unconditioned Response, UR). However, the tone (neutral stimulus) does not. Pavlov s Experiments During conditioning, the neutral stimulus (tone) and the US (food) are paired, resulting in salivation (UR). After conditioning, the neutral stimulus (now Conditioned Stimulus, CS) elicits salivation (now Conditioned Response, CR) Acquisition Acquisition is the initial learning stage in classical conditioning in which an association between a neutral stimulus and an unconditioned stimulus takes place. 1. In most cases, for conditioning to occur, the neutral stimulus needs to come before the unconditioned stimulus. 2. The time in between the two stimuli should be about half a second. 15 classical conditioning Controlling an animal s or a person s responses in such a way that an old response becomes attached to a new stimulus Classical Conditioning Occurs gradually Each pairing of the CS with the UCS strengthens the conditioning Timing is an issue. Conditioning is strongest when the CS is introduced just before the UCS +

4 Stimulus Generalization Tendency to respond to stimuli similar to the CS is called generalization. Pavlov conditioned the dog s salivation (CR) by using miniature vibrators (CS) on the thigh. When he subsequently stimulated other parts of the dog s body, salivation dropped. Stimulus Discrimination Discrimination is the learned ability to distinguish between a conditioned stimulus and other stimuli that do not signal an unconditioned stimulus Extinction When the US (food) does not follow the CS (tone), CR (salivation) begins to decrease and eventually causes extinction. Spontaneous Recovery After a rest period, an extinguished CR (salivation) spontaneously recovers, but if the CS (tone) persists alone, the CR becomes extinct again Classical Conditioning & Human Behavior O. Hobart & Mollie Mowrer used classical conditioning to find a practical solution to bedwetting. Bell and pad device two metallic sheets perforated with small holes and attached by wires to a battery-powered alarm. Classical Conditioning & Human Behavior Placed under the child s bedsheets. When the sleeping child begins to moisten the sheet, the first drops of urine complete the circuit and cause the alarm to go off, waking the child so that he or she can use the bathroom. After several pairings of the full bladder (CS) and the alarm (UCS), the child is able to awaken to the sensation of a full bladder without the help of the alarm.

5 Taste Aversions The person tries out a new food. Several hours later, he or she gets violently sick. He or she will probably blame the new food and in the future will become nauseated by even seeing the new food, even if it is not the cause of the illness. Taste Aversions John Garcia and R.A. Koelling (1966) tested rats by associating flavored water with flashing lights and an electric shock. Gustavson, et al (1974) taught coyotes to hate the taste of sheep by giving them shots after eating sheep that made them sick. Teaching the coyotes to avoid eating sheep satisfied sheep ranchers and naturalists. Applications of Classical Conditioning The Case of Little Albert Watson used classical conditioning procedures to develop advertising campaigns for a number of organizations, including Maxwell House, making the coffee break an American custom. John B. Watson Brown Brothers 27 John B. Watson and Rosalie Rayner experimented on a well-adjusted 9 monthold human infant with classical conditioning. The Case of Little Albert Albert showed no fear when he was presented with a variety of objects including a rat, blocks, a rabbit, a dog, a monkey, masks with and without hair, cotton, wool and burning newspapers. All stimuli were neutral to him. The Case of Little Albert When 11 months old, they placed a white furry rat in front of Albert. Every time he reached for the rat, they would it a metal bar with a hammer behind him, making a loud noise. The noise paired with the sight of the rat elicited fear. After a few pairings, Albert feared not only rats, but anything that was white and furry.

6 Criticisms of Little Albert Experiments Made an otherwise healthy child fearful. The researchers made no attempt to extinguish the CR even though they knew he was leaving the experiment. Mary Cover Jones, one of Watson s students, developed methods for reducing people s fears by pairing things which people are fearful of with pleasant stimuli. Ethics of Research with Human Participants Ethical procedures have been developed by the American Psychological Association in research with human participants Ethical Principles Planning research Ethical problems are resolved before the research starts Responsibility Psychologists are responsible for the dignity and welfare of participants Compliance with law and standards Follow all federal and state laws, as well as professional guidelines Ethical Principles Research responsibilites except for anonymous surveys, nauralistic observations and similar research, psychologists reach an agreement regarding rights and responsibilities of both subjects and researchers before research is begun. Informed consent If consent is required, psychologists obtain a signed informed consent before starting any research with a subject. They inform subjects of the nature of the research so that they are free to take part or decline to take part. Ethical Principles Deception in research Deception is only used in research if no better alternative is available. Under no condition may decption be used about any negative aspects that might influence a subject s willingness to participate Reinforcement B.F. Skinner has been the psychologist most often associated with operant conditioning. He believed that most behavior is influenced by one s history of rewards and punishments Reinforcement is defined as a stimulus or event that affects the likelihood that an immediately preceding behavior will be repeated.

7 Skinner s Experiments Skinner s experiments extend Thorndike s thinking, especially his law of effect. This law states that rewarded behavior is likely to occur again. 37 Yale University Library Operant Chamber Using Thorndikeʹs law of effect as a starting point, Skinner developed the Operant chamber, or the Skinner box, to study operant conditioning. Walter Dawn/ Photo Researc From The Essentials of Conditioning and Learning, 3 rd Edition by Michael P. Domjan, Used with permission by Thomson Learning, Wadsworth Division 38 Operant Chamber The operant chamber, or Skinner box, comes with a bar or key that an animal manipulates to obtain a reinforcer like food or water. The bar or key is connected to devices that record the animal s response. Operant vs. Classical Conditioning In classical conditioning, the experimenter presents the CS and UCS independent of the subject s behavior. Reactions to the CS are then observed. In operant conditioning, the subject must engage in a behavior in order for the programmed outcome to occur. Operant conditioning is learning from the consequences of behavior 39 Types of Reinforcers Reinforcement: Any event that strengthens the behavior it follows. A heat lamp positively reinforces a meerkat s behavior in the cold. Primary & Secondary Reinforcers 1. Primary Reinforcer: An innately reinforcing stimulus like food or drink. 2. Conditioned Reinforcer: A learned reinforcer that gets its reinforcing power through association with the primary reinforcer. Reuters/ Corb 41 42

8 Immediate & Delayed Reinforcers 1. Immediate Reinforcer: A reinforcer that occurs instantly after a behavior. A rat gets a food pellet for a bar press. Reinforcement Schedules 1. Continuous Reinforcement: Reinforces the desired response each time it occurs. 2. Delayed Reinforcer: A reinforcer that is delayed in time for a certain behavior. A paycheck that comes at the end of a week. We may be inclined to engage in small immediate reinforcers (watching TV) rather than large delayed reinforcers (getting an A in a course) which require 2. Partial Reinforcement: Reinforces a response only part of the time. Though this results in slower acquisition in the beginning, it shows greater resistance to extinction later on. consistent study Ratio Schedules 1. Fixed ratio schedule: Reinforces a response only after a specified number of responses. e.g., piecework pay. 2. Variable ratio schedule: Reinforces a response after an unpredictable number of responses. This is hard to extinguish because of the unpredictability. (e.g., behaviors like gambling, fishing.) Interval Schedules 1. Fixed interval schedule: Reinforces a response only after a specified time has elapsed. (e.g., preparing for an exam only when the exam draws close.) 2. Variable interval schedule: Reinforces a response at unpredictable time intervals, which produces slow, steady responses. (e.g., pop quiz.) Schedules of Reinforcement Stimulus Control In operant conditioning, stimuli associated with receiving rewards or punishments become signals for particular behaviors. Organisms learn to generalize among and discriminate between stimuli that serve as signals in operant conditioning. 47

9 Stimulus Control In such cases, the signal is called a secondary reinforcer or conditioned reinforcer. Without the conditioning process, it would be a neutral stimulus, with no intrinsic value With conditioning, almost any stimulus can acquire almost any value. Stimulus Control In such cases, the signal is called a secondary reinforcer or conditioned reinforcer. Without the conditioning process, it would be a neutral stimulus, with no intrinsic value With conditioning, almost any stimulus can acquire almost any value. Stimulus Control Wolfe (1936) did a study with chimpanzees in which poker chips which have no value for chimps (not edible or fun to play with) developed value to the chimps, much as money has value to humans. A machine dispensed peanuts or bananas, when chimps inserted a poker chip. The chimps earned poker chips by pulling down on a heavily weighted bar. Stimulus Control With repetition, poker chips became reinforcers themselves. Chimps would work for them, save them and sometimes try to steal them from one another. Another example, smiles for newborn babies. No value of their own to newborns, but become signals that a baby will be picked up, cuddled, perhaps fed. The smiles become a reward of their own in time. Aversive Control Reinforcement is often used to refer only to pleasant consequences of behavior But psychologists use the term to refer to anything that increases the frequency of an immediately preceding behavior Aversive or unpleasant consequences influence much of our daily behavior We refer to conditioning which uses this type of reinforcer as aversive control. Aversive Control There are two ways in which aversive stimuli can affect our behavior: As negative reinforcers As punishers Negative reinforcement painful or unpleasant stimuli is removed or not applied at all. Two types: Escape conditioning Avoidance conditioning

10 Punishment An aversive event that decreases the behavior it follows. 55 Punishment Although there may be some justification for occasional punishment (Larzelaere & Baumrind, 2002), it usually leads to negative effects. 1. Results in unwanted fears. 2. Conveys no information to the organism. 3. Justifies pain to others. 4. Causes unwanted behaviors to reappear in its absence. 5. Causes aggression towards the agent. 6. Causes one unwanted behavior to appear in place of another. 56 Escape Conditioning Avoidance Conditioning Escape conditioning behavior allows the subject to escape the aversive stimulus already presented. Child served a food it doesn t like Whines and gags The disliked food is removed Whining and gagging are reinforced and will probably be used again when another food it dislikes is introduced Avoidance conditioning subject s behavior prevents an unpleasant situation from happening If child s whining and gagging kept the mother from even serving the disliked food, the behavior would be classified as avoidance conditioning Cognition & Operant Conditioning Evidence of cognitive processes during operant learning comes from rats during a maze exploration in which they navigate the maze without an obvious reward. Rats seem to develop cognitive maps, or mental representations, of the layout of the maze (environment). Latent Learning Such cognitive maps are based on latent learning, which becomes apparent only when an incentive is given (Tolman & Honzik, 1930)

11 Intrinsic Motivation Intrinsic Motivation: The desire to perform a behavior for its own sake. Extrinsic Motivation: The desire to perform a behavior due to promised rewards or threats of punishments. 61 Punishment In punishment, an unpleasant consequence occurs and decreases the frequency of the behavior that produced it. Negative reinforcement and punishment act in opposite ways: In negative reinforcement, escape or avoidance behavior is repeated, and increases in frequency. In punishment, behavior that is punished decreases or is not repeated Disadvantages of Using Aversive Control Aversive stimuli can produce unwanted side effects such as rage, aggression, and fear Then instead of one problem behavior to change, there may be additional behaviors such as aggressive behavior toward other children. A second problem is that people learn to avoid the person delivering the aversive stimuli. Therefore parents and teacher s have less opportunity to correct a child s inappropriate behavior. Factors That Affect Learning Feedback Transfer Practice Feedback Finding out the results of an action or performance Without feedback, may repeat same errors many times Without feedback, would not be reinforced for correct actions to encourage continuing Transfer Transfer of a skill that you have already learned to help you learn a new skill. Ex.: If you have already learned to play the saxophone, you can use those skills to help you learn to play the clarinet Positive transfer previously learned responses help you master a new task Negative transfer previously learned responses actually make it harder to learn the new task

12 Practice The repetition of a task Helps to bind responses together Practice works best when done over a period of time instead of all at once. Mental practice can be used by athletes. Though not as effective as physical practice, better than not practicing. Learning Strategies Problem-solving skills may transfer from one type of problem to other similar problems If a strategy works, a person, or an animal is likely to use it again Harry Harlow Harry Harlow (1949) performed experiments to show that animals could learn to learn. Monkey had to find which lid raisins were hid under. First, using different sizes and shapes of wooden lids, color was the key, always under green lids. When solved, changed the experiment to shape of lid. Eventually monkey could solve the problem without making any more than itk Learned Helplessness & Laziness If a person has numerous experiences in which his actions have no effect on the world, he may learn a general strategy of learned helplessness or laziness If rewards come without effort, a person never learns to work (learned laziness) If pain comes no matter how hard one tries, a person gives up (learned helplessness). Hiroto (1974) One group of college students was able to turn off an unpleasant loud noise Another group was not able to turn off the noise Later placed in a situation where all they had to do to turn off the loud noise was to pull a lever, the group who could turn it off before turned it off, the other group didn t even try Seligman s 3 Elements of Learned Helplessness Stability Globality Internality

13 Stability A person s belief that the state of helplessness results from a permanent characteristic instead of something temporary in nature. Ex.: I am not any good at taking tests. I always do poorly and I always will (stable), rather than I did poorly on the math test because I was sick or I didn t get enough sleep last night. (temporary) Globality A person decides that the state of helplessness comes from a global reason rather than specific. Ex.: Rather than I am not good at taking math tests (specific), I am just dumb (global) Internality A person attributes an undesirable outcome to their own inadequacies instead of to external reasons. Ex.: Using a stability or a globality focus to explain poor performance on the math test instead of an external reason: This was a poorly designed math test. Shaping A technique of operant conditioning in which the desired behavior is molded by first rewarding any act similar to that behavior and then requiring closer and closer approximations to desired behavior before giving the reward. Shaping Shaping is the operant conditioning procedure in which reinforcers guide behavior towards the desired target behavior through successive approximations. Khamis Ramadhan/ Panapress/ G A rat shaped to sniff mines. A manatee shaped to discriminate objects of different shapes, colors and sizes. Fred Bavendam/ Peter Arno 77 Teaching a Rat to Raise a Miniature Flag The experimenter places a rat on a table with a miniature flag pole in the center. When the rat sniffs the flagpole, he gets rewarded. He starts sniffing the flagpole a lot, hoping to get rewarded again. But the reward is withheld until the rat lifts a paw.

14 Teaching a Rat to Raise a Miniature Flag The experimenter continues to reward the rat as it comes closer and closer to the desired activity. Eventually the rat raises up on its hind legs and nibbles on the cord. He is rewarded. Suddenly he nibble on the cord and yanks it. He is rewarded and the rat begins pulling rapidly on the cord and the new response is shaped. The Military Shapes Complicated Behaviors in Animals During WWI, the British trained seagulls to detect enemy submarines in the English Channel. During WWII, B.F. Skinner was involved in a project teaching pigeons to guide missiles to enemy targets. The U.S. Navy has trained dolphins to detect enemy divers and locate undersea mines. Sea lions have been taught to recover antisubmarine rockets. Combining Responses: Chaining To learn a new skill, a person must be able to put various new responses together. Responses that follow one another in a sequence are put together in response chains. Each response produces the signal for the next response. Chains of responses are organized into larger response patterns. Combining Responses: Chaining A complex response like swimming has three major chains: An arm stroking chain A breathing chain A leg-kicking chain It is often necessary learn simple responses before mastering the complex pattern Modeling In addition to classical and operant conditioning, there is a third type of learning called modeling which is observing and imitating. Modeling There are three types of modeling: 1. The simplest case, observing others behavior increases the chance that we will do the same thing. Others clap, we clap. Others look up, we look up. This does not involve learning of new responses, but in using old responses that we are currently not using.

15 Modeling Albert Bandura 2. Observational learning. We observe and imitate. Ex.: watch someone perform dance steps and then imitate to learn the steps ourselves 3. Disinhibition When an observer watches someone engage in a threatening activity without being punished, the observer is more likely to not be inhibited from the same activity. May eliminate a phobia. Behavior Modification The systematic application of learning principles to change people s actions and feelings. Modeling, classical-conditioning and operant-conditioning are used to modify behavior. Computer-Assisted Instruction Greek philosopher and teacher Socrates taught his students by a conversational method, similar to what is used today in CAI. CAI is a refinement of a concept of programmed instruction first introduced by Pressey in 1926 and refined by B.F. Skinner in the 1950s. Computer-Assisted Instruction CAI is based on operant conditioning, guiding the student through instruction by breaking down the instruction into frames. As the student masters a concept, he or she is positively reinforced in the form of new information. Token Economies Cohen & Filipczak, 1970 A group of boys labeled uneducable were placed in a token economy where they were rewarded with points for good grades on tests. They could cash in these points for snacks, lounge privileges or ordered items from a mail-order catalog. Within a few months the IQ of the boys improved an average of 12 ½ points.

16 Token Economies Miller and Schneider, 1970 Used a token economy to teach preschoolers in a Head Start program to write. The children received tokens they could use for food, movies and other rewards. The children in the token economy improved dramatically whereas those not in the token economy made little progress and showed a less postive attitude toward school. Token Economies In token economies, people are paid to act appropriately. In overcrowded mental hospitals, the only way some patients can get attention is by acting crazy. Most attendants do not have time to bother with people not causing trouble. In effect, people are rewarded for undesirable behavior.