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Learning . Chapter 5. Definition of Learning. Learning is any relatively permanent change in behavior brought on by experience or practice “relatively permanent” refers to the fact that when people learn anything, some part of their brain is physically changed to record what they’ve learned
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Learning Chapter 5
Definition of Learning • Learning is any relatively permanent change in behavior brought on by experience or practice • “relatively permanent” refers to the fact that when people learn anything, some part of their brain is physically changed to record what they’ve learned • This is actually a process of memory, without the ability to remember, people cant learn anything • “experience or practice” refers to the tendency for behavior to differ based on the experience of specific events • If a behavior results in a positive experience, it is likely to occur again • If a behavior results in a negative experience, it is not likely to occur again
Classical Conditioning • Ivan Pavlov – studied the digestive system of dogs • Reflex – an involuntary response that is not under personal control or choice • Ex. Dogs salivate when the receive food • Stimulus – any object, event, or experience that causes a response (the reaction of an organism) • Ex. Food given to dogs that causes the reflexive response of salivation • Pavlov noticed that his dogs were salivating when they weren’t supposed to • Some would start salivating when they saw the lab assistant bringing their food, some when they heard the clatter of the food bowl from the kitchen, some when it was the time of day when they were usually fed • Thus, Pavlov switched his focus to study these responses and eventually termed the phenomenon classical conditioning • Learning to make an involuntary (reflex) response to a stimulus other than the original, natural stimulus that normally produces the reflex
Elements of Classical Conditioning • Unconditioned stimulus (UCS) – the original, naturally occurring stimulus that leads to an involuntary (reflex) response • Unconditioned because it is unlearned • In Pavlov’s research, food is the UCS • Unconditioned response (UCR) – an involuntary (reflex) response to a naturally occurring or UCS • Also unlearned, occurs because of genetic “wiring” in the nervous system • In Pavlov’s research, salivation is the UCR • Conditioned stimulus (CS) – stimulus that becomes able to produce a learned reflex response by being paired with the original UCS • Almost any stimulus can become associated with a UCS if it is paired with UCS often enough • Before a stimulus is associated with a UCS it is called a neutral stimulus (NS) – stimulus that has no effect on the desired response • After being paired with the UCS enough times to produce the reflexive response alone, the NS becomes the CS • In Pavlov’s research, lab assistant bringing food, bell, or clatter of the food bowl is the CS • Conditioned response (CR) – learned reflex response to a CS • Is usually not as strong as the original UCR, but is essentially the same response • In Pavlov’s research salivation in response to the lab assistant or clatter of the food bowl is the CR
Pavlov’s Famous Experiments • Paired the ticking of a metronome with the presentation of food • Because the metronome’s ticking didn’t normally produce salivation it was the NS before any conditioning took place • CR and UCR are both salivation • They differ because they are in response to different things • UCR occurs after a UCS • CR occurs after a CS • Food (UCS) produces salivation (UCR) • Food (UCS) is repeatedly paired with sound of the metronome (NS) • After pairings: sound of the metronome (CS) produces salivation (CR)
Pavlov’s Basic Principles of Classical Conditioning • The CS must come before the USC • If the sound of the metronome came just after the dogs received food, they did not become conditioned • The CS and USC must come very close together in time – no more than 5 seconds • With the time between the potential CS and the UCS was extended to several minutes, no association between the two was made • Too much could happen in the longer interval of time to interfere with conditioning • Recent studies have found that the interstimulus interval (ISI), the time between the CS and UCS can vary depending on the nature of the conditioning task and even the organism being conditioned • Shorter ISIs (less than 500 milliseconds) have been found to be ideal for conditioning • The NS must be paired with the UCS several times • Often many pairings are necessary • The CS is usually some stimulus that is distinctive, or stands out, from other competing stimuli • The metronome was a sound that was not normally present in the laboratory and, therefore, was distinct
Stimulus Generalization and Discrimination • Stimulus generalization – the tendency to respond to a stimulus that is similar to the original conditioned stimulus with the conditioned response • Pavlov noticed that similar sounds to the metronome would produce a similar CR • Strength of the response is not as strong as to the original CR • Stimulus discrimination – the tendency to stop making a generalized response to a stimulus that is similar to the original CS because the similar stimulus is never paired with the UCS • Pavlov never paired the sounds similar to the metronome with food • Because only the real CS (metronome) was followed with food (UCS) the dogs learned to tell the difference, or discriminate, between the “fake” sounds and the actual CS • This occurs when an organism learns to respond to different stimuli in different ways
Extinction and Spontaneous Recovery • Extinction – the disappearance or weakening of a learned response following the removal or absence of the UCS • When the CS (metronome’s ticking) was repeatedly presented without the UCS (food), the CR (salivation) “died out” or stopped occurring • In theory, this occurs because new learning has taken place • During extinction, the CS-UCS association that was learned, weakens, as the CS no longer predicts the UCS • For Pavlov’s dogs, they learned not to salivated to the metronome because it no longer predicted food • Spontaneous recovery – the reappearance of a learned response after extinction has occurred • After extinction, Pavlov waited a few weeks before letting the dogs hear the metronome again, when he brought it back, they began to salivate again • This brief recovery of the CR shows that the CR is still retained even after extinction (remember that learning is relatively permanent), so something that is learned is really “still in there” even after extinction • It is just suppressed or inhibited by the lack of an association with the UCS • As time passes, this inhibition weakens, especially if the original CS has not been present for a while
Higher-Order Conditioning • Occurs when a strong CS is paired with a NS, causing the NS to become a second CS • At the point that Pavlov’s dogs were strongly conditioned to salivate (CR) when they heard the metronome (CS) if another sound, like a snap (NS), occurred just before the metronome (CS) enough times, the snap (NS) would become a CS and produce salivation (CR) by itself • Food (UCS) would have to be presented every now and then to maintain the original CR of salivation to the metronome (CS) • Without the UCS the higher-order conditioning would be difficult to maintain and would gradually fade away
Conditioned Emotional Responses • Conditioned emotional responses – emotional response that has become classically conditioned to occur to learned stimuli • John Watson’s classic “Little Albert” experiment demonstrated the classical conditioning of a phobia (an irrational fear response) • Presentation of a white rat was paired with a loud scary noise until Albert feared the white rat • Before conditioning: white rat = NS • During conditioning: white rat (NS) paired with loud noise (UCS) to produce fear (UCR) • After conditioning: white rat (CS) produces fear (CR) • In advertising, commercials often use things that are known to produce an emotional response in hopes that the emotional response will become associated with their product (ex. Attractive women or cuddly puppies)
Vicarious Conditioning • Vicarious conditioning – classical conditioning of a reflex response or emotion by watching the reaction of another person • Ex. Children used to receive vaccination shots in school • The nurse would line children up, and one by one they would receive the shot • When some children received their shots, they cried a lot • By the time the nurse got to the end of the line of children, they were all crying, many of them before the needle even touched their skin • The children had learned their fear response to the shot from watching the reactions of the children who went before them
Other Conditioned Responses • Conditioned taste aversion – development of a nausea or aversive response to a particular taste because that taste was followed by a nausea reaction, occurring after only one association • Ex. The chemotherapy drugs that cancer patients receive can create severe nausea, which usually causes them to develop a taste aversion to anything they eat up to 6 hours before the treatment • Biological preparedness – the tendency of animals to learn certain associations, such as taste and nausea, with only one or few pairings due to the survival value of the learning • Ex. If an animal eats something that makes them sick, they are likely to avoid that food in the future, which increases their chances of survival and passing on their genes to future generations • These 2 types of conditioning violate 2 of Pavlov’s basic principles • The pairing of the CS and USC being close in time • Taste aversion can develop even if the food was eaten a considerable time before nausea occurs • It should take multiple pairing of the CS and UCS to achieve conditioning • Because of biological preparedness, taste aversion can occur with only one or few parings of the stimulus food with the nausea response
Why Does Classical Conditioning Work? • 2 ways to explain how one stimulus can come to “stand for” another • Stimulus substitution – Pavlov’s original theory • Suggested that the CS, through its association close in time with the UCS, came to activate the same place in the brain that was originally activated by the UCS • But if a mere association in time is all that is needed, why would conditioning not work when the CS is presented immediately after the UCS • Cognitive perspective – modern explanation • Suggests that the CS provides information or an expectancy about the coming of the UCS • The CS has to provide some kind of information about the coming of the UCS in order to achieve conditioning • If the CS comes after the UCS it can’t provide any information about when the UCS is coming • Ex. If rats experience an electric shock (UCS) while a specific tone (NS) is played, they will expect a shock (UCS) to occur during the tone (CS) and become anxious (CR) when they hear the tone • But if the shock (UCS) comes immediately after the tone stops (NS), they will act normally when hearing the tone and anxious (CR) when it stops (CS), because they expect that during the tone a shock will not occur
Operant Conditioning • Classical conditioning is the kind of learning that occurs with reflexive, involuntary behavior • Operant conditioning is the kind of learning that applies to voluntary behavior • Operant conditioning – the learning of voluntary behavior through the effects of pleasant and unpleasant consequences to responses
Thorndike’s Puzzle Box: How to Frustrate a Cat • Thorndike would place a hungry cat inside a “puzzle box” from which the only escape was to press a lever on the floor of the box • A bowl of food was placed outside the box, so the hungry cat would be highly motivated to get out • The cat would move around the box, pushing and rubbing against the walls trying to escape and would eventually push the lever by accident and open the door • The lever is the stimulus, the pushing of the lever is the response, and the consequence is both escape from the box and food • After a number of trials the cat took less and less time to push the lever • Its important not to assume the cat had “figured out” the connection between the lever and freedom, Thorndike kept moving the lever to a different position, and the cat had to learn the whole process over again • The cat would simply push and rub around the same area that had worked the last time and each time found the lever a little more quickly
Thorndike’s Law of Effect • Based on his “puzzle box” research Thorndike developed the law of effect • If an action is followed by a pleasurable consequence, it will tend to be repeated, and if followed by an unpleasant consequence, it will tend not to be repeated • This is the basic principle behind learning voluntary behavior • In the case of the “puzzle box,” pushing of the lever was followed by a pleasurable consequence (freedom and food), so pushing the lever became a repeated response
B.F. Skinner: The Next Behaviorist • Skinner took leadership of behaviorism after Watson • He combined the work of Pavlov and Thorndike into a way to explain that all behavior is the product of learning • Skinner is who actually termed the learning of voluntary behavior operant conditioning • Voluntary behavior is what people and animals do to operate in the world • Important distinction between operant and classical conditioning • In classical conditioning, learning a reflex depends on what comes BEFORE the response (UCS), and what will become the CS • In operant conditioning, learning depends on what happens AFTER the response, the consequence
The Concept of Reinforcement • Reinforcement – any event or stimulus, that when following a response, increases the probability that the response will occur again • Typically, reinforcement is pleasurable • But, reinforcement can also be negative, like avoiding something unpleasant • Ex. When a behavior causes the removal of pain • Skinner’s research involved something called a “Skinner box” or “operant conditioning chamber” • Often involved placing a rat into one of the chambers and training it to push down on a bar to get food
Primary and Secondary Reinforcers • Reinforcers are not all alike, there are 2 types • Primary – any reinforcer that is naturally reinforcing by meeting a basic biological need, such as hunger or touch • Infants, toddlers, preschool age children, and animals can be easily reinforced with primary reinforcers • Ex. You can reinforce a toddlers behavior with candy • Secondary – any reinforcer that becomes reinforcing after being paired with a primary reinforcer, such as praise, money, or gold stars • Ex. Money can be a reinforcer because it is associated with the ability to obtain (purchase) things that meet basic needs, such as food and shelter =
Positive and Negative Reinforcement • Reinforcers can also differ in the way they are used • Positive reinforcement – the reinforcement of a response by the addition or experiencing of a pleasurable stimulus • Ex. Every time a rat presses a bar it receives food. The rat’s pressing of the bar is positively reinforced by the pleasurable reward of food • Negative reinforcement – the reinforcement of a response by the removal, escape from, or avoidance of an unpleasant stimulus • Ex. If during a mild electric shock, if a rat presses a bar the shock stops. The rat’s pressing of the bar is negatively reinforced by the removal of the painful shock stimulus
Schedules of Reinforcement • The timing of reinforcement can have a tremendous difference in the speed at which learning occurs and the strength of the learned response • Consider this scenario: Heather’s mother gives her a quarter every night she remembers to put her dirty cloths in the hamper. Sean’s mother gives him gives him a dollar at the end of the week, but only if he has put his cloths in the hamper every night that week. • Which child will learn to put their cloths in the hamper more quickly? • After both Heather and Sean have been conditioned to put their dirty cloths in the hamper, if both mothers stop giving money, which child is more likely to continue to putting their dirty cloths in the hamper the longest?
The Partial Reinforcement Effect • Continuous reinforcement – the reinforcement of each and every correct response • Responses that are reinforced each time they occur are more easily and quickly learned • Ex. Therefore, because Heather was reinforced every night with a quarter, she will learn the association faster than Sean • Partial reinforcement effect – the tendency for a response that is reinforced after some, but not all, correct responses to be very resistant to extinction • Ex. Sean expected to get a reinforcer only after 7 correct responses, when his reinforcers stop, he might continue to put his dirty cloths in the hamper for several more days or even another week or so, hoping that the reinforcer will eventually come anyway • Heather will probably stop putting her dirty cloths in the hamper more quickly than Sean because she expects to be reinforced after every correct response
The Partial Reinforcement Effect • Partial reinforcement can be accomplished according to different patterns or schedules • It might be a certain interval of time that’s important • Whentiming of the response is more important, it is called an interval schedule • Ex. If an office safe can only be opened at a specific time of day, it wouldn’t matter how many times a person tried to open it because it would only work at a specific time • Ex. A rat can only get 1 food pellet for pressing a lever every 2 hours, regardless of how many times the bar is pressed • Or it might be the number of responses required that’s important • When the number of responses is more important, the schedule is called a ratio schedule, because a certain number of responses is required for each reinforcer • Ex. If a person had to sell a certain number of raffle tickets in order to get a prize • Ex. A rat must press a bar 10 times to get a food pellet, regardless of how long it takes • Another way schedules of reinforcement can differ is in whether the number of responses or interval of time is fixed (the same every time) or variable(a different number or interval is required in each case) • So it’s possible to have a fixed interval schedule, a variable interval schedule, a fixed ratio schedule, and a variable ratio schedule
Fixed Interval Schedule of Reinforcement • Fixed Interval Schedule – schedule of reinforcement in which the interval of time that must pass before reinforcement becomes possible is always they same • Ex. Receiving a paycheck at the end of each week • If you were teaching a rat to press a lever to get food pellets, you might require it to push the lever at least once within a 2 minute time span to get a pellet • It wouldn’t matter how many times the rat pushed the bar; the rat would only get a pellet at the end of the 2 minute interval if it had pressed the bar at least once
Fixed Interval Schedule of Reinforcement • Fixed interval schedule of reinforcement does not produce a fast rate of responding • Since it only matters that at least one response is made during the specific interval of time, speed is not that important • Eventually the rat will start pushing the lever only as the interval of time nears its end, which is what causes the “scalloping” effect seen in the graph • The response rate goes up just before the reinforcer and then drops off immediately after, until it is almost time for the next reinforcer Ex. This is similar to the way factory workers speed up production just before payday and slow down just after payday
Variable Interval Schedule of Reinforcement • Variable interval schedule of reinforcement – the interval of time that must pass before reinforcement becomes possible is different for each trial or event • A rat might receive a food pellet when it pushes a lever, every 5 minutes on average, but sometimes the interval might be 2 minutes, sometimes 10 • But the rat must push the lever at least once after that 2 or 10 minute interval to get the pellet • Because the rat cant predict how long the interval is going to be, it pushes the bar more or less continuously, producing the smooth line on the graph Ex. Dialing a busy phone number, because you don’t know when the call will go through, you keep dialing and dialing Ex. Pop quizzes are unpredictable, students don’t know exactly what day they might be given a quiz, so the best strategy is to study a little every night just in case
Fixed Ratio Schedule of Reinforcement • Fixed ratio schedule of reinforcement – the number of responses required for reinforcement is always the same • Notice 2 things about the graph • The rate of responding is very fast, especially compared to the fixed interval schedule • Rapid response rate occurs because the rat wants to get to the next reinforcer as fast as possible, and the number of lever pushes counts • There are little “breaks” in the response pattern immediately after a reinforcer is given • The pauses or breaks come right after a reinforcer, because the rat knows “about how many” lever pushes will be needed to get to the next reinforcer because it’s always the same • Fixed schedules, both interval and ratio, are predictable, which allow rest breaks Ex. Some sandwich shops give out punch cards to their customers that get punched every time they buy a sandwich, when the card has 10 punches, the customer might get a free sandwich
Variable Ratio Schedule of Reinforcement • Variable ratio schedule of reinforcement – the number of responses required for reinforcement is different for each trial or event • The rat might be expected to push the bar an average of 20 time to get reinforcement, that means that sometimes the rat would push the lever 10 times before a reinforcer comes, but on other trials it might take 30 presses or more • In the graph, the line is just as rapid a response rate as the fixed ratio schedule because the number of responses still matters • But the graph is much smoother because the rat is taking no rest breaks because it doesn’t know how many times it may have to push the lever to get the next food pellet • Unpredictabilitymakes the variable schedule responses more or less continuous Ex. People who put money into a slot machine continuously, do so because the don’t know how many times they will have to do this until the jackpot comes. They do this continuously because “the next one” might hit the jackpot. The same is true with lottery tickets and pretty much any sort of gambling
Additional Factors to Effective Reinforcement • Regardless of the schedule of reinforcement, 2 additional factors contribute to making reinforcement of a behavior as effective as possible • Timing • In general, a reinforcer should be given as immediately as possible after the desired behavior • Delaying reinforcement tends not to work well, especially when dealing with animals and small children • Reinforce only the desired behavior • This should be obvious, but everyone makes mistakes sometimes • Ex. Many parents make the mistake of giving a child who has not done some chore the promised treat anyway, which completely undermines the child’s learning of that chore or task • Also, who hasn’t given a treat to a pet that has not really done the trick?
Examples: which kind of reinforcement is going on? • Andy’s father nags him to wash his car. Andy hates being nagged, so he washes the car so his father will stop nagging. • Negative reinforcement, washing his car removes the unpleasant stimulus of his father nagging • Bradley learns that talking in a funny voice gets him lots of attention from his classmates, so now he talks that way often. • Positive reinforcement, increasing use of the voice to get attention • Tina is a server at a restaurant and always tries to smile and be pleasant because that seems to lead to bigger tips • Positive reinforcement, Tina’s smiling and pleasantness are reinforced by better tips • Will turns his report in to his teacher on the day it is due because papers get marked down a letter grade for every day they are late • Negative reinforcement, avoiding the unpleasant stimulus of being marked down a grade by turning in a paper on time
The Role of Punishment in Operant Conditioning • Thinking back to positive and negative reinforcement • These strategies are important for increasing the likelihood that the targeted behavior will occur again • But what about a behavior we do not want to occur again? • Punishment…
How Does Punishment Differ From Reinforcement? • People experience 2 kinds of things as consequences in the world • Things they like (ex. Food, money, candy, sex, praise, etc.) • Things they don’t like (ex. Spankings, being yelled at, experiencing any kind of pain, etc.) • Additionally, people experience these two kinds of consequences in 1 of 2 ways • Directly (ex. Getting money for working or getting yelled at for misbehaving) • Or they don’t experience them at all (ex. Losing an allowance for misbehaving or avoiding a scolding by lying about misbehavior)
2 Kinds of Punishment • Punishment – any event or object that, when following a response, makes that response less likely to happen again • Punishment by application – the punishment of a response by the addition or experiencing of an unpleasant stimulus • This is the kind of punishment people usually think of • Ex. Spanking • Punishment by removal – the punishment of a response by the removal of a pleasurable stimulus • This is the kind of punishment people normally confuse with negative reinforcement • Ex. “grounding” a teenager is removing the freedom to do what the teenager wants to do
Negative reinforcement occurs when a response is followed by the removal of an unpleasant stimulus • If something unpleasant has just gone away as a consequence of that response, the response will tend to happen again • If the response increases, the consequence has to be some kind of reinforcement • Punishment by removal occurs when a response if followed by the removal of a pleasant stimulus • If something pleasant is taken away as a consequence of a response, the response probably will not happen again • If the response decreases, the consequence has to be some type of punishment • In both, something is removed, but the difference between them is what is taken away and the result it has on behavior
Problems With Punishment • Although punishment can be effective in reducing or weakening a behavior, it has several drawbacks • Punishment is used to weaken a response, and getting rid of a response that is already well established isn’t easy • In reinforcement, all that has to be done is strengthen an already existing response • Punishment usually serves to temporarily suppress or inhibit a behavior until enough time has passed • Ex. Punishing a child’s bad behavior doesn’t always eliminate the behavior completely • As time goes on, the punishment is forgotten, and the “bad” behavior may occur again in a kind of spontaneous recovery of the old (probably pleasurable) behavior • Punishment by application can be pretty severe, and severe punishments do one thing well: it stops the behavior immediately • It may not stop it permanently, but it does stop it • In a situation in which a child might be doing something dangerous or self-injurious, this kind of punishment is sometimes more acceptable • Ex. If a child starts to run into a busy street, the parent might scream at the child to stop and then administer several rather severe swats to the child’s rear • If this is not usual behavior for the parent, the child will most likely never run into the street again
Problems With Punishment • Other than situations of immediately stopping dangerous behavior, severe punishment has too many drawbacks to be really useful (it can also lead to abuse) • Severe punishment may cause a child (or animal) to avoid the punisher instead of the behavior being punished, so the child (or animal) learns the wrong response • Severe punishment may encourage lying to avoid the punishment (a kind of negative reinforcement), again, not the response that is desired • Severe punishment creates fear and anxiety, emotional responses that do not promote learning, if the point is to teach something, this kind of consequence isn’t going to help • Hitting provides a successful model for aggression
Problems With Punishment • Punishment as a model for aggression • The adult is using aggression to get he/she wants from the child • Children sometimes become more likely to use aggression to get what they want when they receive this kind of punishment • And, the adult has lost an opportunity to model a more appropriate way to deal with parent-child disagreements • Since aggressive punishment does tend to stop the undesirable behavior, at least for a little while, the parent actually experiences a kind of negative reinforcement • When they spank, the unpleasant behavior goes away • This may increase the tendency to use aggressive punishment over other forms of discipline and can lead to child abuse • Some children are so desperate for their parents’ attention that they will misbehave on purpose • The punishment is a form of attention, and these children will take whatever attention they can get, even if it is negative
Problems With Punishment • Punishment by removal is less objectionable and is the only kind of punishment that is permitted in many public schools • But this kind of punishment also has drawbacks • It teaches the child what not to but not what the child should do • Both punishment by removal and punishment by application are usually only temporary in their effect on behavior • As time passes, the behavior will most likely return as the memory of the punishment gets weaker, allowing spontaneous recovery of the negative behavior
How to Make Punishment More Effective • Punishment should immediately follow the behavior it is meant to punish • If the punishment comes long after the behavior, it will not be associated with that behavior (also true for reinforcement) • Punishment should be consistent • If the parent says that a certain punishment will follow a certain behavior, the parent must make sure to follow through and do what he/she promised • Punishment for a particular behavior should stay at the same intensity or increase slightly but never decrease • Ex. If a child is scolded for jumping on the bed the first time, the second time the behavior happens the child should be punished by scolding or by a stronger penalty, like removal of a favorite toy • But if the first misbehavior is punished by spanking and the second only by a scolding, the child learns to “gamble” with the possible punishment • Punishment of the wrong behavior should be paired with reinforcement of the right behavior • Pairing punishment with reinforcement allows parents and others to use a much milder punishment and still be effective • It also teaches the desired behavior rather than just suppressing the undesired one • Ex. If a 2 year old is eating with her fingers, the parent should pull her hand gently out of her plate and say something like “No, we don’t eat with our fingers, we eat with our fork.” then place the fork in the child’s hand and praise her for using it, “See, you are doing such a good job with your fork, I’m so proud of you!”
Stimulus Control • Discriminative stimulus – any stimulus that provides the organism with a cue for making a certain response in order to obtain reinforcement • Specific cues lead to specific responses, and discriminating between cues leads to success • Ex. A police car is a discriminative stimulus for slowing down and a red stoplight is a cue for stopping because both of these actions are usually followed by negative reinforcement, people don’t want to get a ticket or get hit by another car • Ex. A doorknob is a cue for where to grab a door to open it • If a door has a knob, people always turn it, but if it has a handle, people usually pull it • The 2 kinds of opening devices each cause a different response from people, and their reward is opening the door
Other Concepts in Operant Conditioning • Shaping – the reinforcement of simple steps in behavior that lead to a desired more complex behavior • Ex. If you wanted to train your dog to jump through a hoop, you would have to start with some behavior that the dog is already capable of doing on its own • Then gradually mold that starting behavior into a jump (something the dog is capable of doing but not likely to do on its own) • You would start with the hoop on the ground in front of the dog and then call the dog through the hoop, using a treat as bait • After the dog steps through the hoop, you give the dog a treat (positive reinforcement) • The next time, you could raise the hoop a little, reward the dog for walking through it again, the raise the hoop again, reward again, and so on • The goal is achieved by reinforcing each Successive approximation • Successive approximations – small steps in behavior, one after the other, that lead to a particular goal behavior
Other Concepts in Operant Conditioning • Extinction in operant condition involves the removal of the reinforcement (in classical conditioning, extinction involves the removal of the UCS) • Ex. If a child is throwing a tantrum to get a candy bar, if the parent does not cave in and removes the reinforcement (the candy bar) and if possible parental attention, the tantrum will eventually stop • Operantly conditioned responses can also be generalized to stimuli that are similar to the original stimulus (just like in classical conditioning) • Ex. When a baby is first learning to label objects and people, he may say “Dada” when his father is present, and the father reinforces the behavior with praise and attention • But sometimes the baby will call all men “Dada,” but over time as other men fail to reinforce this response, he’ll learn to discriminate among them and his father and only call his father “Dada” • In this way, the man who is actually his father becomes a discriminative stimulus • Spontaneous recovery also occurs in operant conditioning (just like in classical conditioning) • Ex. In the example of teaching the dog to jump through the hoop, if the dog has already learned other tricks, like rolling over or shaking paws, when learning a new trick the dog may try to get a reinforcer by performing its old tricks, before finally walking through the hoop
Using Operant Conditioning: Behavior Modification • Behavior modification – the use of operant conditioning techniques to bring about desired changes in behavior • Used for many years to change undesirable behavior and create desirable responses in animals and humans, particularly in school children • If a teacher wants to use behavior modification to help a child learn to be more attentive during lectures • Select a target behavior, such as making eye contact with the teacher • Choose a reinforcer, such as a gold star applied to the child’s chart on the wall • Every time the child makes eye contact, the teacher gives the child a gold star. Inappropriate behavior, such as looking out the window, is not reinforced with gold stars • At the end of the day, the teacher gives the child a special treat or reward for having a certain number of gold stars (reward is decided ahead of time and discussed with the child) • The gold stars in the example above, can be considered tokens, secondary reinforcers that can be traded in for other kinds of reinforcers • Token economy – type of behavior modification in which desired behavior is rewarded with tokens • Commonly used in programs like Alcoholics Anonymous
Using Operant Conditioning: Behavior Modification • Another tool behaviorists use to modify behavior is called time-out • Time-out – form of mild punishment by removal in which a misbehaving animal, child, or adult is placed in a special area away from the attention of others • Essentially, the organism is being “removed” from any possibility of positive reinforcement in the form of attention Horrible but hilarious time out method…
Using Operant Conditioning: Behavior Modification • Applied behavior analysis (ABA) – modern term for a form of behavior modification that uses both analysis of current behavior and behavioral techniques to address a socially relevant issue • Ex. ABA has been used as a technique involving shaping to teach social skills to individuals with Autism • Small pieces of candy are used as reinforcers to teach social skills and language to children with autism • In ABA, skills are broken down into their simplest steps and then taught to the child through a system of reinforcement • Prompts (such as moving a child’s face to look at a teacher on a task) are given as needed when the child is learning a skill or refuses to cooperate • As the child begins to master a skill and receives reinforcement in the form of treats or praise, the prompts are gradually taken away until the child can do the skill independently
Using Operant Conditioning: Behavior Modification • Techniques for modifying responses have been developed so that even biological responses, normally considered involuntary, such as blood pressure, muscle tension, and hyperactivity can be brought under conscious control • Biofeedback – using feedback about biological conditions to bring involuntary responses, such as blood pressure and relaxation, under voluntary control • Relatively newer biofeedback technique, called neurofeedback involves trying to change brain-wave activity • Involves amplifiers connected to a computer that records and analyzes the physiological activity of the brain • Neurofeedback can be integrated with video-game-like programs that individuals can use to learn how to produce brain waves or specific types of brain activity associated with specific cognitive or behavioral states (ex. increased attention, staying focused, relaxed awareness)
Cognitive Learning Theory • Behaviorists believed that only observable, measurable behavior should be studied • But, other psychologists had an interest in cognition, the mental events that take place inside a person’s mind while behaving • These individuals began to dominate the field of experimental psychology • Behaviorists could no longer ignore the thoughts, feelings, and expectations that clearly existed in the mind and that seemed to influence observable behavior • They eventually began to develop a cognitive learning theory to supplement the more traditional theories of learning (conditioning) • There are 3 important people that are often cited as key theorists in the early days of the development of cognitive learning theory • Gestalt psychologists Edward Tolmanand Wolfgang Kohler, and modern psychologist Martin Seligman
Latent Learning: Tolman’s Maze-Running Rats • Tolman’s best-known experiments in learning involved teaching 3 groups of rats the same maze, one at a time • 1st group – each rat was placed in the maze and reinforced with food for making its way out the other side • The rat was then placed back in the maze, reinforced when it completed the maze again, and so on until the rat could successfully solve the maze without making any errors (like wrong turns) • 2nd group – rats were treated exactly like the first group except they didn’t get any reinforcement when they exited the maze, they were simply put back over and over again for the 1st 9 days • On the 10th day, the rats began to receive reinforcement for getting out of the maze • 3rd group – served as a control group and were not reinforced over the entire course of the experiment