Distinguishing "positive" from "negative" in these cases is largely a matter of emphasis. For example, in a very warm room, a current of external air serving as reinforcement may be positive because it is relatively cool but negative because it removes the uncomfortably hot air.
Some reinforcement can simultaneously be both positive and negative. For example, a drug addict may take drugs for the added euphoria and to get rid of withdrawal symptoms.
Another example is eating. Eating adds pleasurable flavors while removing feelings of hunger. The distinction seems to have no real use in research or applied psychology, although one may some day be found. Until then, many behavioral psychologists simply refer to reinforcement or punishment —without polarity—to cover all consequent environmental changes. Punishment is any change in an animal's surroundings that occurs after a given behavior or reponse which reduces the frequency of that behavior occuring again in the future.
As with reinforcement, it is the behavior , not the animal, that is punished. Whether a change is or is not punishing is only known by its effect on the rate of the behavior, not by any "hostile" features of the change. In positive punishment or type I punishment , an experimenter punishes a response by adding an aversive stimulus into the animal's surroundings a brief electric shock, for example.
In negative punishment or type II punishment , a positive reinforcer is removed as in the removal of a feeding dish. As with reinforcement, it is not usually necessary to speak of positive and negative in regard to punishment.
Punishment is not a mirror effect of reinforcement. In experiments with laboratory animals and studies with children, punishment decreases the frequency of a previously reinforced response only temporarily, and it can produce other "emotional" behavior wing-flapping in pigeons, for example and physiological changes increased heart rate, for example that have no clear equivalents in reinforcement.
Punishment is considered by some behavioral psychologists to be a "primary process" — a completely independent phenomenon of learning, distinct from reinforcement. Others see it as a category of negative reinforcement, creating a situation in which any punishment-avoiding behavior even standing still is reinforced. Aversive stimulus , punisher , and punishing stimulus are synonyms. Punishment may be used for a an aversive stimulus or b the occurrence of any punishing change or c the part of an experiment in which a particular response is punished.
Shaping involves reinforcing successive, increasingly accurate approximations of a response desired by a trainer. In training a rat to press a lever, for example, simply turning toward the lever will be reinforced at first. Then, only turning and stepping toward it will be reinforced. As training progresses, the response reinforced becomes progressively more like the desired behavior. Chaining is similar but involves reinforcing various simple behaviors separately and then linking them together in a more complex series.
The standard idea of behavioral reinforcement has been criticized as circular, since it appears to argue that response strength is increased by reinforcement while defining reinforcement as something which increases response strength. Other definitions have been proposed, such as F.
Instead of rewarding only the target behavior, in shaping , we reward successive approximations of a target behavior. Why is shaping needed? Remember that in order for reinforcement to work, the organism must first display the behavior. Shaping is needed because it is extremely unlikely that an organism will display anything but the simplest of behaviors spontaneously. In shaping, behaviors are broken down into many small, achievable steps. The specific steps used in the process are the following: Reinforce any response that resembles the desired behavior.
Then reinforce the response that more closely resembles the desired behavior. You will no longer reinforce the previously reinforced response. Next, begin to reinforce the response that even more closely resembles the desired behavior.
Continue to reinforce closer and closer approximations of the desired behavior. Finally, only reinforce the desired behavior. Shaping is often used in teaching a complex behavior or chain of behaviors. Skinner used shaping to teach pigeons not only such relatively simple behaviors as pecking a disk in a Skinner box, but also many unusual and entertaining behaviors, such as turning in circles, walking in figure eights, and even playing ping pong; the technique is commonly used by animal trainers today.
An important part of shaping is stimulus discrimination. This discrimination is also important in operant conditioning and in shaping behavior. They use shaping to help him master steps toward the goal. Instead of performing the entire task, they set up these steps and reinforce each step. First, he cleans up one toy. Second, he cleans up five toys. Third, he chooses whether to pick up ten toys or put his books and clothes away. Fourth, he cleans up everything except two toys.
Finally, he cleans his entire room. Rewards such as stickers, praise, money, toys, and more can be used to reinforce learning. How did the rats learn to press the lever in the Skinner box? They were rewarded with food each time they pressed the lever. For animals, food would be an obvious reinforcer.
What would be a good reinforce for humans? For your daughter Sydney, it was the promise of a toy if she cleaned her room. How about Joaquin, the soccer player?
If you gave Joaquin a piece of candy every time he made a goal, you would be using a primary reinforcer. Primary reinforcers are reinforcers that have innate reinforcing qualities. These kinds of reinforcers are not learned. Water, food, sleep, shelter, sex, and touch, among others, are primary reinforcers. Pleasure is also a primary reinforcer. Organisms do not lose their drive for these things. For most people, jumping in a cool lake on a very hot day would be reinforcing and the cool lake would be innately reinforcing—the water would cool the person off a physical need , as well as provide pleasure.
A secondary reinforcer has no inherent value and only has reinforcing qualities when linked with a primary reinforcer. Another example, money, is only worth something when you can use it to buy other things—either things that satisfy basic needs food, water, shelter—all primary reinforcers or other secondary reinforcers. If you were on a remote island in the middle of the Pacific Ocean and you had stacks of money, the money would not be useful if you could not spend it.
What about the stickers on the behavior chart? They also are secondary reinforcers. Sometimes, instead of stickers on a sticker chart, a token is used. Tokens, which are also secondary reinforcers, can then be traded in for rewards and prizes. Entire behavior management systems, known as token economies, are built around the use of these kinds of token reinforcers. Token economies have been found to be very effective at modifying behavior in a variety of settings such as schools, prisons, and mental hospitals.
For example, a study by Cangi and Daly found that use of a token economy increased appropriate social behaviors and reduced inappropriate behaviors in a group of autistic school children. Autistic children tend to exhibit disruptive behaviors such as pinching and hitting. When they hit or pinched, they lost a token. The children could then exchange specified amounts of tokens for minutes of playtime. The main principle comprises changing environmental events that are related to a person's behavior.
For example, the reinforcement of desired behaviors and ignoring or punishing undesired ones. This is not as simple as it sounds — always reinforcing desired behavior, for example, is basically bribery.
There are different types of positive reinforcements. Primary reinforcement is when a reward strengths a behavior by itself. Secondary reinforcement is when something strengthens a behavior because it leads to a primary reinforcer. Token economy is a system in which targeted behaviors are reinforced with tokens secondary reinforcers and later exchanged for rewards primary reinforcers.
Tokens can be in the form of fake money, buttons, poker chips, stickers, etc. While the rewards can range anywhere from snacks to privileges or activities. For example, teachers use token economy at primary school by giving young children stickers to reward good behavior. Token economy has been found to be very effective in managing psychiatric patients.
However, the patients can become over reliant on the tokens, making it difficult for them to adjust to society once they leave prison, hospital, etc. Staff implementing a token economy programme have a lot of power. It is important that staff do not favor or ignore certain individuals if the programme is to work. Therefore, staff need to be trained to give tokens fairly and consistently even when there are shift changes such as in prisons or in a psychiatric hospital.
A further important contribution made by Skinner is the notion of behavior shaping through successive approximation. Skinner argues that the principles of operant conditioning can be used to produce extremely complex behavior if rewards and punishments are delivered in such a way as to encourage move an organism closer and closer to the desired behavior each time. To do this, the conditions or contingencies required to receive the reward should shift each time the organism moves a step closer to the desired behavior.
According to Skinner, most animal and human behavior including language can be explained as a product of this type of successive approximation. In the conventional learning situation, operant conditioning applies largely to issues of class and student management, rather than to learning content. It is very relevant to shaping skill performance.
A simple way to shape behavior is to provide feedback on learner performance, e. A variable-ratio produces the highest response rate for students learning a new task, whereby initially reinforcement e.
For example, if a teacher wanted to encourage students to answer questions in class they should praise them for every attempt regardless of whether their answer is correct. Gradually the teacher will only praise the students when their answer is correct, and over time only exceptional answers will be praised.
Unwanted behaviors, such as tardiness and dominating class discussion can be extinguished through being ignored by the teacher rather than being reinforced by having attention drawn to them. Knowledge of success is also important as it motivates future learning. However, it is important to vary the type of reinforcement given so that the behavior is maintained.
Skinner's study of behavior in rats was conducted under carefully controlled laboratory conditions. Note that Skinner did not say that the rats learned to press a lever because they wanted food. He instead concentrated on describing the easily observed behavior that the rats acquired. In the Skinner study, because food followed a particular behavior the rats learned to repeat that behavior, e. Therefore research e. Skinner proposed that the way humans learn behavior is much the same as the way the rats learned to press a lever.
So, if your layperson's idea of psychology has always been of people in laboratories wearing white coats and watching hapless rats try to negotiate mazes in order to get to their dinner, then you are probably thinking of behavioral psychology. Behaviorism and its offshoots tend to be among the most scientific of the psychological perspectives. The emphasis of behavioral psychology is on how we learn to behave in certain ways.
We are all constantly learning new behaviors and how to modify our existing behavior. Operant conditioning can be used to explain a wide variety of behaviors, from the process of learning, to addiction and language acquisition. It also has practical application such as token economy which can be applied in classrooms, prisons and psychiatric hospitals.
However, operant conditioning fails to take into account the role of inherited and cognitive factors in learning, and thus is an incomplete explanation of the learning process in humans and animals.
For example, Kohler found that primates often seem to solve problems in a flash of insight rather than be trial and error learning. Also, social learning theory Bandura, suggests that humans can learn automatically through observation rather than through personal experience.
The use of animal research in operant conditioning studies also raises the issue of extrapolation. Some psychologists argue we cannot generalize from studies on animals to humans as their anatomy and physiology is different from humans, and they cannot think about their experiences and invoke reason, patience, memory or self-comfort.
McLeod, S. Skinner - operant conditioning.
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