Candy is an appetitive stimulus that is used to increase or maintain the desired behavior. If a child misbehaves, they might have their television privileges revoked. This is negative punishment , because you've removed an appetitive stimulus TV in order to eliminate an unwanted behavior. If the child continues to misbehave, a parent might yell at him or her; this would constitute positive punishment. It involves the application of an aversive stimulus yelling , in order to eliminate the unwanted behavior.
Finally, the frustrated parent might negotiate with their misbehaving child by offering to reduce the chores that he or she must complete that week in exchange for the desired behavior.
This is a form of negative reinforcement , since an aversive stimulus chores is removed in the service of increasing good behavior. When it comes to training animals or sometimes, humans , reinforcement is delivered according to a predefined schedule. If a stimulus is delivered after a set number of responses, it is considered a fixed ratio schedule.
For example, a pigeon might be given a food reward after every tenth time that it pecks a button. The pigeon would learn that ten button presses are required in order to receive a reward. If the number of responses required to receive a stimulus varies, then you are using a variable ratio schedule. The best example for this is a slot machine, which has a fixed probability of delivering a reward over time, but a variable number of pulls between rewards.
It is no wonder that variable ratio reinforcement schedules are the most effective for quickly establishing and maintaining a desired behavior. If a stimulus is given after a fixed amount of time, regardless of the number of responses, then you've got a fixed interval schedule.
No matter how many times the pigeon pecks the button, it only receives one reward every ten minutes. This is the least effective reinforcement schedule. Finally, if a stimulus is given after a variable amount of time, you've got a variable interval schedule. A stimulus might be applied every week on average , which means sometimes it occurs more often than once per week week, and sometimes less often. Pop quizzes are the best known example of variable interval reinforcement schedules, since the precise time at which they occur is unpredictable.
The desired response in this case is studying. In general, ratio schedules are more effective at modifying behavior than interval schedules, and variable schedules are more effective than fixed schedules.
Skinner took the lessons he learned from his early pigeon experiments and went on to develop methods for eliciting more complex behaviors by dividing them into segments, each of which could then be individually conditioned. This is called chaining , and forms the basis for training dogs to drive cars.
The behaviorists who worked with the driving dogs first trained them to operate a lever, then to use a steering wheel to adjust the direction of a moving cart, then to press or depress a pedal to speed up or slow down the cart. As each dog mastered each step, an additional segment was added until they learned the entire target behavior.
Unlike pigeons, for whom food is the best reward, the domestication process has meant that dogs can be rewarded with verbal praise alone though food definitely helps. How are such unnatural behaviors elicited in the first place? By using a combination of reinforcement and punishment, a trainer can shape a desired behavior by rewarding successively closer approximations. Skinner referred to this process, appropriately, as shaping. In , Skinner described it this way emphasis added :.
We first give the bird food when it turns slightly in the direction of the spot from any part of the cage. This increases the frequency of such behavior. We then withhold reinforcement until a slight movement is made toward the spot. This again alters the general distribution of behavior without producing a new unit. We continue by reinforcing positions successively closer to the spot, then by reinforcing only when the head is moved slightly forward, and finally only when the beak actually makes contact with the spot.
The original probability of the response in its final form is very low; in some cases it may even be zero. In this way we can build complicated operants which would never appear in the repertoire of the organism otherwise.
By reinforcing a series of successive approximations, we bring a rare response to a very high probability in a short time. The total act of turning toward the spot from any point in the box, walking toward it, raising the head, and striking the spot may seem to be a functionally coherent unit of behavior; but it is constructed by a continual process of differential reinforcement from undifferentiated behavior, just as the sculptor shapes his figure from a lump of clay.
The clicker training featured in the chicken and goat videos, and used by many for training dogs, combines classical and operant conditioning.
Initially, rewards are given for even crude approximations of the target behavior—in other words, even taking a step in the right direction. Then, the trainer rewards a behavior that is one step closer, or one successive approximation nearer, to the target behavior.
For example, Skinner would reward the rat for taking a step toward the lever, for standing on its hind legs, and for touching the lever—all of which were successive approximations toward the target behavior of pressing the lever.
As the subject moves through each behavior trial, rewards for old, less approximate behaviors are discontinued in order to encourage progress toward the desired behavior. For example, once the rat had touched the lever, Skinner might stop rewarding it for simply taking a step toward the lever.
In this way, shaping uses operant-conditioning principles to train a subject by rewarding proper behavior and discouraging improper behavior. This process has been replicated with other animals—including humans—and is now common practice in many training and teaching methods. It is commonly used to train dogs to follow verbal commands or become house-broken: while puppies can rarely perform the target behavior automatically, they can be shaped toward this behavior by successively rewarding behaviors that come close.
Shaping is also a useful technique in human learning. For example, if a father wants his daughter to learn to clean her room, he can use shaping to help her master steps toward the goal. First, she cleans up one toy and is rewarded.
Second, she cleans up five toys; then chooses whether to pick up ten toys or put her books and clothes away; then cleans up everything except two toys. Through a series of rewards, she finally learns to clean her entire room. Reinforcement and punishment are principles of operant conditioning that increase or decrease the likelihood of a behavior.
Reinforcement and punishment are principles that are used in operant conditioning. Reinforcement means you are increasing a behavior: it is any consequence or outcome that increases the likelihood of a particular behavioral response and that therefore reinforces the behavior. The strengthening effect on the behavior can manifest in multiple ways, including higher frequency, longer duration, greater magnitude, and short latency of response.
Punishment means you are decreasing a behavior: it is any consequence or outcome that decreases the likelihood of a behavioral response. Extinction , in operant conditioning, refers to when a reinforced behavior is extinguished entirely. This occurs at some point after reinforcement stops; the speed at which this happens depends on the reinforcement schedule, which is discussed in more detail in another section.
Both reinforcement and punishment can be positive or negative. In operant conditioning, positive and negative do not mean good and bad. Instead, positive means you are adding something and negative means you are taking something away. All of these methods can manipulate the behavior of a subject, but each works in a unique fashion. See the blue text and yellow text above, which represent positive and negative, respectively.
Similarly, reinforcement always means you are increasing or maintaining the level of a behavior, and punishment always means you are decreasing the level of a behavior. See the green and red backgrounds above, which represent reinforcement and punishment, respectively.
The stimulus used to reinforce a certain behavior can be either primary or secondary. A primary reinforcer, also called an unconditioned reinforcer, is a stimulus that has innate reinforcing qualities. These kinds of reinforcers are not learned. Water, food, sleep, shelter, sex, touch, and pleasure are all examples of primary reinforcers: organisms do not lose their drive for these things. Some primary reinforcers, such as drugs and alcohol, merely mimic the effects of other reinforcers.
For most people, jumping into 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, also called a conditioned reinforcer, has no inherent value and only has reinforcing qualities when linked or paired with a primary reinforcer. Before pairing, the secondary reinforcer has no meaningful effect on a subject. Money is one of the best examples of a secondary reinforcer: it is only worth something because you can use it to buy other things—either things that satisfy basic needs food, water, shelter—all primary reinforcers or other secondary reinforcers.
A schedule of reinforcement is a tactic used in operant conditioning that influences how an operant response is learned and maintained. Each type of schedule imposes a rule or program that attempts to determine how and when a desired behavior occurs. Behaviors are encouraged through the use of reinforcers, discouraged through the use of punishments, and rendered extinct by the complete removal of a stimulus. Schedules vary from simple ratio- and interval-based schedules to more complicated compound schedules that combine one or more simple strategies to manipulate behavior.
Continuous schedules reward a behavior after every performance of the desired behavior. This reinforcement schedule is the quickest way to teach someone a behavior, and it is especially effective in teaching a new behavior. Simple intermittent sometimes referred to as partial schedules, on the other hand, only reward the behavior after certain ratios or intervals of responses.
There are several different types of intermittent reinforcement schedules. These schedules are described as either fixed or variable and as either interval or ratio.
Fixed refers to when the number of responses between reinforcements, or the amount of time between reinforcements, is set and unchanging. Variable refers to when the number of responses or amount of time between reinforcements varies or changes.
Interval means the schedule is based on the time between reinforcements, and ratio means the schedule is based on the number of responses between reinforcements. Simple intermittent schedules are a combination of these terms, creating the following four types of schedules:.
All of these schedules have different advantages. In general, ratio schedules consistently elicit higher response rates than interval schedules because of their predictability. For example, if you are a factory worker who gets paid per item that you manufacture, you will be motivated to manufacture these items quickly and consistently.
Variable schedules are categorically less-predictable so they tend to resist extinction and encourage continued behavior. Both gamblers and fishermen alike can understand the feeling that one more pull on the slot-machine lever, or one more hour on the lake, will change their luck and elicit their respective rewards.
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. Simply Psychology. Bandura, A. Social learning theory. Ferster, C. Schedules of reinforcement. New York: Appleton-Century-Crofts. Kohler, W. The mentality of apes. Skinner, B. The behavior of organisms: An experimental analysis. New York: Appleton-Century. Superstition' in the pigeon. Journal of Experimental Psychology, 38 , How to teach animals. Science and human behavior. Thorndike, E. Animal intelligence: An experimental study of the associative processes in animals.
Psychological Monographs: General and Applied, 2 4 , i Watson, J. Psychology as the behaviorist views it. Psychological Review, 20 , — Presenting the subject with something that it likes.
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