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Learning and Cognitive Processes Understanding Psychology Chapter 2
How Do We Learn? We learn by association. Our minds naturally connect events that occur in sequence. q
learning A relatively permanent change in behavior that results from experience
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Associative Learning
How Do We Learn? 2000 years ago, Aristotle suggested this law of association.
Learning to associate one stimulus with another.
Then 200 years ago Locke and Hume reiterated this law.
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Associative Learning
Associative Learning
Learning to associate one stimulus with another.
Learning to associate a response with a consequence.
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Three Basic Types of Learning:
Associative Learning Learning to associate a response with a consequence.
• Classical conditioning • Operant conditioning • Modeling
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Classical Conditioning
Classical Conditioning
Sovfoto
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 f l for later behaviorists like John Watson. b h i i lik J h W
Ivan Pavlov (1849‐1936)
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Pavlov’s Experiments
Pavlov’s Experiments
Before conditioning, food (Unconditioned Stimulus, US) produces salivation (Unconditioned Response, UR). However, the tone (neutral stimulus) does not.
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) li i ( C di i dR CR)
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Acquisition Acquisition is the initial learning stage in classical conditioning in which an association between a neutral stimulus and an unconditioned stimulus takes place.
classical conditioning
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.
Controlling an animal’s or a person’s responses in such a way that an old response becomes attached to a new stimulus 15
Classical Conditioning • Occurs gradually • Each pairing of the CS with the UCS strengthens the conditioning • Timing Ti i is i an issue. i Conditioning C diti i is i strongest when the CS is introduced just before the UCS
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Stimulus Generalization
Stimulus Discrimination Discrimination is the learned ability to distinguish between a conditioned stimulus and other stimuli that do not signal an unconditioned stimulus.
Tendency to respond to stimuli similar to the CS is called generalization. Pavlov conditioned the dog’s g salivation (CR) by using miniature vibrators (CS) on the thigh. When he subsequently stimulated other parts of the dog’s body, salivation dropped. 19
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Extinction
Spontaneous Recovery
When the US (food) does not follow the CS (tone), CR (salivation) begins to decrease and eventually causes extinction.
After a rest period, an extinguished CR (salivation) spontaneously recovers, but if the CS (tone) persists alone, the CR becomes extinct again.
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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.
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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, 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.
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Taste Aversions
Taste Aversions • John Garcia and R.A. Koelling (1966) tested rats by associating flavored water with flashing lights and an electric shock. • Gustavson, 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.
• The person tries out a new food. • Several later, S l hours h l t he h or she h gets t 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.
Applications of Classical Conditioning
The Case of Little Albert • John B. Watson and Rosalie Rayner experimented on a well-adjusted 9 monthold human infant with classical conditioning. conditioning
John B. Watson
Brown Brothers
Watson used classical conditioning procedures to p g develop advertising campaigns for a number of organizations, including Maxwell House, making the “coffee break” an American custom.
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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 b i newspapers. All stimuli burning ti li were neutral t l 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 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.
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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. 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.
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
Ethics of Research with Human Participants • Ethical procedures have been developed by the American Psychological Association in research with human participants
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
Reinforcement
• 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
• 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.
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Skinner’s Experiments
Operant Chamber
Skinner’s experiments extend Thorndike’s thinking, especially his law of effect. This law states that rewarded behavior is likely to occur again.
From The Essentials of Co onditioning and Learning, 3rd Edition by Michael P. Domjjan, 2005. Used with permission by Thomson Learning, Wa adsworth Division
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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
Operant Chamber
Yale University Library
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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
The operant chamber, or Skinner box, comes with a bar or key that an animal manipulates p to obtain a reinforcer like food or water. The bar or key is connected to devices that record the animal’s response. 39
Types of Reinforcers
Primary & Secondary Reinforcers
Reinforcement: Any event that strengthens the behavior it follows. A heat lamp positively reinforces a meerkat’s behavior in the cold.
1. Primary Reinforcer: An innately reinforcing stimulus like food or drink. Co ditio ed ei o ce : A A learned ea ed 2.. Conditioned Reinforcer: reinforcer that gets its reinforcing power through association with the primary reinforcer.
Reuters/ Corb
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Reinforcement Schedules
Immediate & Delayed Reinforcers 1. Immediate Reinforcer: A reinforcer that occurs instantly after a behavior. A rat gets a food pellet for a bar press.
1. Continuous Reinforcement: Reinforces the desired response each time it occurs. a tia ei o ce e t: Reinforces a ei o ces a 2.. Partial Reinforcement: response only part of the time. Though this results in slower acquisition in the beginning, it shows greater resistance to extinction later on.
2 D 2. Delayed Reinforcer: l dR i f A i f A reinforcer that is th t i 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 consistent study.
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Interval Schedules
Ratio Schedules 1. Fixed‐ratio schedule: Reinforces a response only after a specified number of responses. e.g., piecework pay.
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 V 2. Variable‐ratio schedule: i bl ti h d l Reinforces a R i f response after an unpredictable number of responses. This is hard to extinguish because of the unpredictability. (e.g., behaviors like gambling, fishing.)
2. Variable‐interval schedule: Reinforces a response at unpredictable time intervals, which produces slow, steady responses. (e.g., pop quiz.) 45
Schedules of Reinforcement
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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.
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Stimulus Control • In such cases, the signal is called a secondary reinforcer or conditioned reinforcer.
Stimulus Control • In such cases, the signal is called a secondary reinforcer or conditioned reinforcer.
– Without the conditioning process process, it would be a neutral stimulus, with no intrinsic value – With conditioning, almost any stimulus can acquire almost any value.
– Without the conditioning process process, it would be a neutral stimulus, with no intrinsic value – With conditioning, almost any stimulus can acquire almost any value.
Stimulus Control
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.
• 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
Aversive Control
• Reinforcement is often used to refer only to pleasant consequences of behavior • But psychologists use the term to refer to y g that increases the frequency q y of anything 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.
• There are two ways in which aversive stimuli can affect our behavior: – As negative reinforcers – As punishers p
• Negative reinforcement – painful or unpleasant stimuli is removed or not applied at all. Two types: – Escape conditioning – Avoidance conditioning
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Punishment
Punishment
An aversive event that decreases the behavior it follows.
Although there may be some justification for occasional punishment (Larzelaere & Baumrind, 2002), it usually leads to negative effects. 1. 2. 3. 4.
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Results in unwanted fears. Results in unwanted fears. Conveys no information to the organism. Justifies pain to others. 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.
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Escape Conditioning
Avoidance Conditioning
• Escape conditioning – behavior allows the subject to escape the aversive stimulus already presented.
• Avoidance conditioning – subject’s behavior prevents an unpleasant situation from happening
– Child served a food it doesn’t 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
– If child child’s s whining and gagging kept the mother from even serving the disliked food, the behavior would be classified as avoidance conditioning
Cognition & Operant Conditioning
Latent Learning
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 develop cognitive maps, or mental representations, of the layout of the maze (environment).
Such cognitive maps are based on latent learning, which becomes apparent only when an incentive is given (Tolman & Honzik, 1930).
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Punishment
Intrinsic Motivation Intrinsic Motivation: The desire to perform a behavior for its own sake.
• In punishment, an unpleasant consequence occurs and decreases the frequency of the behavior that produced it. • Negative reinforcement and punishment act in opposite ways:
Extrinsic Motivation: The desire to perform a behavior due to promised rewards or threats of punishments. 61
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, h th there may b be additional dditi l behaviors b h i 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.
– In negative reinforcement, escape or avoidance behavior is repeated, and increases in frequency. – In punishment, behavior that is punished decreases or is not repeated
Factors That Affect Learning • Feedback • Transfer • Practice P ti
Feedback
Transfer
• 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 of a skill that you have already learned to help you learn a new skill. • Ex.: If you have already learned to play the p , yyou can use those skills to saxophone, 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
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Practice • The repetition of a task • Helps to bind responses together • Practice works best when done over a period i d off ti time iinstead t d off allll att once. • Mental practice can be used by athletes. Though not as effective as physical practice, better than not practicing.
Harry Harlow • Harry Harlow (1949) performed experiments to show that animals could learn to learn. y had to find which lid raisins were • Monkey 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 i t k
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
Learning Strategies • Problem-solving skills may transfer from one type of problem to other similar problems • If a strategy works works, a person person, or an animal is likely to use it again
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).
Seligman’s 3 Elements of Learned Helplessness • Stability • Globality • Internality I t lit
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Stability
Globality • A person decides that the state of helplessness comes from a global reason rather than specific.
• A person’s belief that the state of helplessness results from a permanent characteristic instead of something g temporary in nature.
– Ex.: Ex : Rather than “II am not good at taking math tests” (specific), “I am just dumb” (global)
– 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)
Internality
Shaping
• A person attributes an undesirable outcome to their own inadequacies instead of to external reasons. Ex : Using a stability or a globality Ex.: focus to explain poor performance on the math test instead of an external reason: “This was a poorly designed math test.”
• 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.
Teaching a Rat to Raise a Miniature Flag
Shaping Shaping is the operant conditioning procedure in which reinforcers guide behavior towards the desired target behavior through successive approximations. Fred Bavendam/ Peter Arno
Khamis Ramadhan/ Panapress/ G
A rat shaped to sniff mines. A manatee shaped to discriminate objects of different shapes, colors and sizes.
• 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. rewarded • He starts sniffing the flagpole a lot, hoping to get rewarded again. But the reward is withheld until the rat lifts a paw.
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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
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.
• A complex response like swimming has three major chains:
Modeling
Modeling
• In addition to classical and operant conditioning, there is a third type of learning called modeling which is observing and imitating imitating.
– An arm stroking chain – A breathing chain – A leg-kicking chain
• It is often necessary learn simple responses before mastering the complex pattern
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There are three types of modeling: 1. The simplest case, observing others’ behavior increases the chance that we will do the same thing. g Others clap, p, we clap. p 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.
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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, Modeling classical classical-conditioning conditioning and operant-conditioning are used to modify behavior.
Computer-Assisted Instruction • CAI is based on operant conditioning, guiding the student through instruction by breaking down the instruction into “frames frames.” As the student masters a concept, he or she is positively reinforced in the form of new information.
Computer-Assisted Instruction • Greek philosopher and teacher Socrates taught his students by a conversational method, similar to what is used today in CAI. 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.
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.
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Token Economies
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.
• 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.
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