Learning Targets 27 1 Describe operant conditioning Module
Learning Targets 27 -1 Describe operant conditioning. Module 27 Operant Conditioning 27 -2 Identify Skinner, and describe how operant behavior is reinforced and shaped. 27 -3 Differentiate positive reinforcement from negative reinforcement, and identify the basic types of reinforcers. 27 -4 Explain how different reinforcement schedules affect behavior. 27 -5 Differentiate punishment from negative reinforcement, and explain how punishment affects behavior. 27 -6 Describe why Skinner’s ideas provoked controversy.
What is operant conditioning? a type of learning in which a behavior becomes more likely to recur if followed by a reinforcer or less likely to recur if followed by a punisher
A quick comparison refresher… classical conditioning operant conditioning Organisms form associations between stimuli (a CS and the US it signals). Organisms associate their own actions with consequences. Classical conditioning also involves respondent behavior—automatic responses to a stimulus Behavior that operates on the environment to produce rewarding or punishing stimuli is called operant behavior.
AP® Exam Tip 1 You may have to differentiate classical conditioning and operant conditioning on the AP® exam. Classical conditioning is involuntary (respondent) behavior, while operant conditioning is voluntary (operant) behavior.
Who was B. F. Skinner? Skinner was behaviorism’s most influential and controversial figure. His work elaborated on what psychologist Edward L. Thorndike called the law of effect. B. F. Skinner (1904 -1990)
What did Thorndike do? Thorndike used a fish reward to entice cats to find their way out of a puzzle box through a series of maneuvers.
What is the law of effect? Thorndike’s principle that behaviors followed by favorable consequences become more likely, and that behaviors followed by unfavorable consequences become less likely. The cats’ performance tended to improve with successive trials, illustrating Thorndike’s law of effect.
What did Skinner design? For his pioneering studies on operant conditioning, Skinner designed an operant chamber, popularly known as a Skinner box.
What is an operant chamber? in operant conditioning research, a chamber (also known as a Skinner box) containing a bar or key that an animal can manipulate to obtain a food or water reinforcer; attached devices record the animal’s rate of bar pressing or key pecking
How does a Skinner box operate? Inside the box, the rat presses a bar for a food reward. Outside, measuring devices (not shown here) record the animal’s accumulated responses.
What does the Skinner box allow researchers to investigate? The Skinner box creates a stage on which rats and other animals act out Skinner’s concept of reinforcement: any event that strengthens (increases the frequency of) a preceding response. What is reinforcing depends on the animal and the conditions. For people, it may be praise, attention, or a paycheck. For hungry and thirsty rats, food and water work well.
Are all reinforcers created equal? No. What is reinforcing (a heat lamp) to one animal (a cold meerkat) may not be to another (an overheated child).
What makes a reinforcer? It is important to note that a reinforcer is defined by its impact on behavior. A reinforcer increases the likelihood that the behavior will increase. Ice cream may sound like it is a reinforcer for all, but what if the subject is lactose intolerant?
How is behavior shaped through operant conditioning? Shaping is an operant conditioning procedure in which reinforcement guides behavior toward closer and closer approximations of the desired behavior. This is also called reward by successive approximations.
How would Skinner shape a rat’s behavior to press a bar to get food? § First, researchers watch how the animal naturally behaves, to build on its existing behaviors. § The rat would be given a bit of food (reinforcement) each time it approaches the bar. § Once the rat is approaching regularly, food would only be given when it moves close to the bar, then closer still. § Finally, experimenters would require the rat to actually touch the bar to get food.
Discuss the steps you would take to shape the following behaviors. Teaching a dog to retrieve a toy when thrown. Teach your friend to listen to your stories.
What is a discriminative stimulus? a stimulus that elicits a response after association with reinforcement (in contrast to related stimuli not associated with reinforcement) So, Skinner may train a pigeon to peck at a green circle (the discriminative stimulus), but not a red square.
How have pigeons learned to discriminate? After being reinforced with food when correctly spotting breast tumors, pigeons became as skilled as humans at discriminating cancerous from healthy tissue. (Levenson et al. , 2015)
Let’s look at the research on discriminative stimulus training in animals. Dogs have been shaped to sniff out land mines or locate people amid rubble. (La Londe et al. , 2015) After being trained to discriminate among classes of events or objects—flowers, people, cars, chairs—pigeons can usually identify the category in which a new pictured object belongs. (Bhatt et al. , 1988; Wasserman, 1993) Pigeons have even been trained to discriminate between the music of Bach and Stravinsky (Porter & Neuringer, 1984)
Consider this dialogue between a son and father. Isaac: Could you take me to the mall? Dad: (Continues reading paper. ) Isaac: Dad, I need to go to the mall. Dad: Uh, yeah, in a few minutes. Isaac: DAAAAD! The mall!! Dad: Show me some manners! Okay, where are my keys. . . Can you identify the behavior and the reinforcement for both Isaac and his Dad?
How was Isaac’s behavior reinforced? Isaac’s whining behavior is reinforced because his father gives in and drives him to the mall. Is he likely to repeat this whining behavior in the future? YES! Because it worked! It was reinforced! Issac’s behavior was positively reinforced.
How was Dad’s behavior reinforced? Dad’s driving (or agreeing to his son’s demands) behavior is reinforced because his son stopped his irritating whining. Is he likely to agree to his son’s demands again in the future? YES! Because it worked! It was reinforced! Dad’s behavior was negatively reinforced.
What is positive reinforcement? increasing behaviors by presenting positive reinforcers A positive reinforcement is any stimulus that, when presented after a response, strengthens the response.
What is negative reinforcement? increasing behaviors by stopping or reducing aversive stimuli A negative reinforcement is any stimulus that, when removed after a response, strengthens the response.
1. What Would You Answer? The purpose of reinforcement is to A. cause a behavior to stop. B. cause a behavior to diminish. C. cause a behavior to continue. D. strengthen the spontaneous recovery process. E. cause a behavior to occur for only a limited amount of time.
What are examples of positive and negative reinforcement? positive reinforcement studying hard (behavior) to receive an A (reinforcement) from the teacher arriving at work on time (behavior) to receive praise and a pay raise (reinforcement) from your boss negative reinforcement taking an aspirin (behavior) to reduce a painful headache (removal of aversive stimulus) hitting the snooze button (behavior) to shut off an annoying alarm (removal of aversive stimulus)
Reinforcement Identify the types of reinforcement and voluntary behavior in this image.
What was the baby’s behavior and how was it reinforced? The baby’s behavior of crying was positively reinforced. How so? Explain.
What was the parents’ behavior and how was it reinforced? The parents’ behavior of taking the baby into their bed was negatively reinforced. How so? Explain.
AP® Exam Tip 2 Note that negative reinforcement is not punishment. Negative reinforcement—psychology’s most misunderstood concept—removes a punishing (aversive) event. Think of negative reinforcement as something that provides relief—from that whining teenager, bad headache, or annoying seat belt alarm. This term is likely to be on the AP® exam.
What are primary and conditioned (secondary) reinforcers? primary reinforcers innately reinforcing stimuli such as those that satisfy a biological need examples: food, pain relief conditioned (secondary) reinforcers stimuli that gain their reinforcing power through their learned association with a primary reinforcer examples: money, good grades, a pleasant tone of voice
Explain this cartoon in terms of operant conditioning.
How does the immediacy of the reinforcement impact behavior? Some animals will need immediate (within 30 seconds for instance) reinforcement in order to tie the reinforcement to the behavior. Human animals respond to delayed reinforcement…even learn to delay gratification as a point of maturity.
Examples of delayed gratification… The paycheck that comes at the end of the month. The trophy that comes at the end of the season. The good grade that comes at the end of the year.
What are reinforcement schedules? Reinforcement schedules are patterns that define how often a desired response will be reinforced. Two types of reinforcement schedules are: continuous reinforcement schedule partial (intermittent) reinforcement schedule reinforcing the desired response every time it occurs reinforcing a response only part of the time
How does continuous reinforcement impact learning? With continuous reinforcement, learning occurs rapidly, so its the best choice for learning a behavior. Extinction also occurs rapidly. When continuous reinforcement stops, the behavior soon stops (is extinguished). If a normally dependable candy machine fails to deliver a chocolate bar twice in a row, we stop putting money into it (although a week later we may exhibit spontaneous recovery by trying again).
How does partial (intermittent) reinforcement impact learning? Real life rarely provides continuous reinforcement. Salespeople do not make a sale with every pitch. But they persist because their efforts are occasionally rewarded. This persistence is typical with partial (intermittent) reinforcement schedules, in which responses are sometimes reinforced, sometimes not. Learning is slower to appear, but resistance to extinction is greater than with continuous reinforcement.
Parenting lesson break…. Partial reinforcement also works with children. Occasionally giving in to children’s tantrums for the sake of peace and quiet intermittently reinforces the tantrums. This is the very best procedure for making a behavior persist.
What are the four types of partial reinforcement? Fixed ratio schedules: reinforcement occurs after a set number of responses Fixed interval schedules: reinforcement occurs after a set length of time Variable ratio schedules: reinforcement occurs after an unpredictable number of responses Variable interval schedules: reinforcement occurs after an unpredictable length of time
What are examples of the four types of partial reinforcement? Fixed ratio schedules: one free coffee after every 10 purchased Fixed interval schedules: mail arriving at 2 pm every day Variable ratio schedules: payoff on slot machine after a varying number of plays Variable interval schedules: checking our phone for a text from our friend
Use your understanding of partial reinforcement schedules to interpret the graph below. Which method produces the fastest learning that is most resistant to extinction?
Review the four types of partial reinforcement schedules. Can you think of one new example for each from YOUR life?
2. What Would You Answer? Shea bought 100 tickets in the raffle for a free homecoming ticket and lost. Months later she also buys 100 tickets for the senior prom raffle, hoping this will be the time she wins. Which schedule of reinforcement is best used to explain this scenario? A. fixed-ratio B. variable-ratio C. fixed-interval D. variable-interval E. continuous
AP® Exam Tip 3 Students sometimes have difficulty with the schedules of reinforcement. The word interval in schedules of reinforcement means that an interval of time must pass before reinforcement. There is nothing the learner can do to shorten the interval. The word ratio refers to the ratio of responses to reinforcements. If the learner responds with greater frequency, there will be more reinforcements. This concept is likely to be on the AP® exam.
What is punishment and how is it different from negative reinforcement? Punishment is an event that tends to decrease the behavior it follows. Behavior that is punished is less likely to occur again. Punishment adds an aversive stimulus or removes a pleasant stimulus. Negative reinforcement increases the likelihood that the behavior will occur again. Negative reinforcement removes an aversive stimulus. Punishment tells you what not to do; reinforcement tells you what to do.
3. What Would You Answer? Which of the following best describes negative reinforcement? A. John stops shooting bad free-throws because his coach benches him when he does. B. Brian studies hard because it earns him “A” grades in math. C. Lillian used to walk to school but does not do so anymore because she was attacked by a dog last month. D. Charles smokes because his anxiety is reduced when he does so. E. Osel wears his seat belt because his driving teacher cited accident statistics in class.
Just for practice: identify the reinforcement or punishment in each example. A. John stops shooting bad free-throws because his coach benches him when he does. B. Brian studies hard because it earns him “A” grades in math. C. Lillian used to walk to school but does not do so anymore because she was attacked by a dog last month. D. Charles smokes because his anxiety is reduced when he does so. E. Osel wears his seat belt because his driving teacher cited accident statistics in class.
What are two ways to punish unwanted behavior? Positive punishment adds something negative. Negative punishment takes away something positive.
What are four major drawbacks to the use of physical punishment? Punished behavior is suppressed, not forgotten. This temporary state may (negatively) reinforce parents’ punishing behavior. Punishment teaches discrimination among situations. Punishment can teach fear. Physical punishment may increase aggression by modeling violence as a way to cope with problems.
Why did Skinner’s legacy provoke controversy? Critics of Skinner’s principles believed the approach dehumanized people by neglecting their personal freedom and seeking to control their actions. Skinner replied that people’s actions are already controlled by external consequences, and that reinforcement is more humane than punishment as a means for controlling behavior.
Learning Target 27 -1 Review Describe operant conditioning. § Operant conditioning is a type of learning in which behavior is strengthened if followed by a reinforcement or diminished if followed by a punishment.
Learning Target 27 -2 Review Identify Skinner, and describe how operant behavior is reinforced and shaped. § B. F. Skinner was a college English major and aspiring writer who later entered psychology graduate school. He became modern behaviorism’s most influential and controversial figure. § Expanding on Edward Thorndike’s law of effect, B. F. Skinner and others found that the behavior of rats or pigeons placed in an operant chamber (Skinner box) can be shaped by using reinforcers to guide closer and closer approximations of the desired behavior.
Learning Target 27 -3 Review Differentiate positive reinforcement from negative reinforcement. § Reinforcement is any consequence that strengthens behavior. § Positive reinforcement adds a desirable stimulus increasing the likelihood that behavior will repeat. § Negative reinforcement removes an aversive stimulus to increase the frequency of a behavior.
Learning Target 27 -3 Review cont. Identify the basic types of reinforcers. § Primary reinforcers are innately satisfying— no learning is required. § Secondary (conditioned) reinforcers are satisfying because we have learned to associate them with more basic rewards § Immediate reinforcers offer immediate payback; delayed reinforcers require the ability to delay gratification.
Learning Target 27 -4 Review Explain how different reinforcement schedules affect behavior. § A reinforcement schedule defines how often a response will be reinforced. § In continuous reinforcement, learning is rapid, but so is extinction if rewards cease. § In partial (intermittent) reinforcement, initial learning is slower, but the behavior is much more resistant to extinction.
Learning Target 27 -4 Review cont. Explain how different reinforcement schedules affect behavior. § Fixed-ratio schedules reinforce behaviors after a set number of responses; variable-ratio schedules, after an unpredictable number of responses. § Fixed-interval schedules reinforce behaviors after set time periods; variable-interval schedules, after unpredictable time periods.
Learning Target 27 -5 Review Differentiate punishment from negative reinforcement, and explain how punishment affects behavior. § Punishment administers an undesirable consequence or withdraws something desirable in an attempt to decrease the frequency of a behavior. § Negative reinforcement removes an aversive stimulus and increases the likelihood that the behavior will be repeated. § Punishment can have undesirable side effects, such as suppressing rather than changing unwanted behaviors; encouraging, creating fear, teaching aggression, and fostering depression and low self-esteem.
Learning Target 27 -6 Review Describe why Skinner’s ideas provoked controversy. § Critics of Skinner’s principles believed the approach dehumanized people by neglecting their personal freedom and seeking to control their actions. § Skinner replied that people’s actions are already controlled by external consequences, and that reinforcement is more humane than punishment as a means for controlling behavior.
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