Overview:

The theory of B.F. Skinner is based upon the idea that learning is a function of change in overt behavior. Changes in behavior are the result of an individual's response to events (stimuli) that occur in the environment. A response produces a consequence such as defining a word, hitting a ball, or solving a math problem. When a particular Stimulus-Response (S-R) pattern is reinforced (rewarded), the individual is conditioned to respond. The distinctive characteristic of operant conditioning relative to previous forms of behaviorism (e.g., Thorndike, Hull) is that the organism can emit responses instead of only eliciting response due to an external stimulus.

Reinforcement is the key element in Skinner's S-R theory. A reinforcer is anything that strengthens the desired response. It could be verbal praise, a good grade or a feeling of increased accomplishment or satisfaction. The theory also covers negative reinforcers -- any stimulus that results in the increased frequency of a response when it is withdrawn (different from adversive stimuli -- punishment -- which result in reduced responses). A great deal of attention was given to schedules of reinforcement (e.g. interval versus ratio) and their effects on establishing and maintaining behavior.

One of the distinctive aspects of Skinner's theory is that it attempted to provide behavioral explanations for a broad range of cognitive phenomena. For example, Skinner explained drive (motivation) in terms of deprivation and reinforcement schedules. Skinner (1957) tried to account for verbal learning and language within the operant conditioning paradigm, although this effort was strongly rejected by linguists and psycholinguists. Skinner (1971) deals with the issue of free will and social control.

Scope/Application:

Operant conditioning has been widely applied in clinical settings (i.e., behavior modification) as well as teaching (i.e., classroom management) and instructional development (e.g., programmed instruction). Parenthetically, it should be noted that Skinner rejected the idea of theories of learning (see Skinner, 1950).

Example:

By way of example, consider the implications of reinforcement theory as applied to the development of programmed instruction (Markle, 1969; Skinner, 1968)

1. Practice should take the form of question (stimulus) - answer (response) frames which expose the student to the subject in gradual steps

2. Require that the learner make a response for every frame and receive immediate feedback

3. Try to arrange the difficulty of the questions so the response is always correct and hence a positive reinforcement

4. Ensure that good performance in the lesson is paired with secondary reinforcers such as verbal praise, prizes and good grades.

Principles:

1. Behavior that is positively reinforced will reoccur; intermittent reinforcement is particularly effective

2. Information should be presented in small amounts so that responses can be reinforced ("shaping")

3. Reinforcements will generalize across similar stimuli ("stimulus generalization") producing secondary conditioning

BF Skinner: Operant Conditioning

Skinner is regarded as the father of Operant Conditioning, but his work was based on Thorndike’s law of effect. Skinner introduced a new term into the Law of Effect - Reinforcement. Behaviour which is reinforced tends to be repeated (i.e. strengthened); behaviour which is not reinforced tends to die out-or be extinguished (i.e. weakened).

Skinner studied operant conditioning by conducting experiments using animals which he placed in a “Skinner Box” (see fig 2) which was similar to Thorndike’s puzzle box.

BF Skinner coined the term operant conditioning; it means roughly changing of behaviour by the use of reinforcement which is given after the desired response. Skinner identified three types of responses or operant that can follow behaviour.

Skinner coined the term operant conditioning; it means roughly changing of behaviour by the use of reinforcement which is given after the desired response. Skinner identified three types of responses or operant that can follow behaviour.

• Neutral operants: responses from the environment that neither increase nor decrease the probability of a behaviour being repeated.

• Reinforcers: Responses from the environment that increase the probability of a behaviour being repeated. Reinforcers can be either positive or negative.

• Punishers: Response from the environment that decrease the likelihood of a behaviour being repeated. Punishment weakens behaviour.

We can all think of examples of how our own behaviour has been affected by reinforcers and punishers. As a child you probably tried out a number of behaviours and learnt from their consequences. For example, if when you were younger you tried smoking at school, and the chief consequence was that you got in with the crowd you always wanted to hang out with, you would have been positively reinforced (i.e. rewarded) and would be likely to repeat the behaviour. If, however, the main consequence was that you were caught, caned, suspended from school and your parents became involved you would most certainly have been punished, and you would consequently be much less likely to smoke now.

Reinforcement (strengthens behaviour)

Skinner showed how positive reinforcement worked by placing a hungry rat in his Skinner box. The box contained a lever in the side and as the rat moved about the box it would accidentally knock the lever. Immediately it did so a food pellet would drop into a container next to the lever. The rats quickly learned to go straight to the lever after a few times of being put in the box. The consequence of receiving food if they pressed the lever ensured that they would repeat the action again and again.

Positive reinforcement strengthens a behaviour by providing a consequence an individual finds rewarding. For example, if your teacher gives you £5 each time you complete your homework (i.e. a reward) you are more likely to repeat this behaviour in the future, thus strengthening the behaviour of completing your homework.

The removal of an unpleasant reinforcer can also strengthen behaviour. This is known as Negative Reinforcement because it is the removal of an adverse stimulus which is ‘rewarding’ to the animal. Negative reinforcement strengthens behaviour because it stops or removes an unpleasant experience.

For example, if you do not complete your homework you give your teacher £5. You will complete your homework to avoid paying £5, thus strengthening the behaviour of completing your homework.

Skinner showed how negative reinforcement worked by placing a rat in his Skinner box and then subjecting it to an unpleasant electric current which caused it some discomfort. As the rat moved about the box it would accidentally knock the lever. Immediately it did so the electric current would be switched off. The rats quickly learned to go straight to the lever after a few times of being put in the box. The consequence of escaping the electric current ensured that they would repeat the action again and again.

In fact Skinner even taught the rats to avoid the electric current by turning on a light just before the electric current came on. The rats soon learned to press the lever when the light came on because they knew that this would stop the electric current being switched on.

These two learned responses are known as Escape Learning and Avoidance Learning.

Punishment (weakens behaviour)

Punishment is defined as the opposite of reinforcement since it is designed to weaken or eliminate a response rather than increase it. Like reinforcement, punishment can work either by directly applying an unpleasant stimulus like a shock after a response or by removing a potentially rewarding stimulus, for instance, deducting someone’s pocket money to punish undesirable behaviour.

Note: It is not always easy to distinguish between punishment and negative reinforcement.

Operant Conditioning Summary

Looking at Skinner's classic studies on pigeons’ behaviour we can identify some of the major assumptions of behaviourists approach.

• Psychology should be seen as a science, to be studied in a scientific manner. Skinner's study of behaviour in rats was conducted under carefully controlled laboratory conditions.

• Behaviourism is primarily concerned with observable behaviour, as opposed to internal events like thinking and emotion. Note that Skinner did not say that the rats learnt to press a lever because they wanted food. He instead concentrated on describing the easily observed behaviour that the rats acquired.

• The major influence on human behaviour is learning from our environment. In the Skinner study, because food followed a particular behaviour the rats learned to repeat that behaviour, e.g. classical and operant conditioning.

• There is little difference between the learning that takes place in humans and that in other animals. Therefore research (e.g. classical conditioning) can be carried out on animals (Pavlov’s dogs) as well as on humans (Little Albert). Skinner proposed that the way humans learn behaviour 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 behavioural psychology.

Behaviourism and its offshoots tend to be among the most scientific of the psychological perspectives. The emphasis of behavioural psychology is on how we learn to behave in certain ways. We are all constantly learning new behaviours and how to modify our existing behaviour. Behavioural psychology is the psychological approach that focuses on how this learning takes place.

Reference :

http://www.simplypsychology.pwp.blueyonder.co.uk/operant-conditioning.html

http://tip.psychology.org/skinner.html

B.F. Skinner's Behavioural Theory

Parents have long known that children respond to a system of rewards and punishments. While to say that this is a simplification of the theories of famed behaviourist B.F. Skinner would be an understatement it is accurately descriptive of the most basic aspect of his beliefs. Operant behaviour and operant conditioning, Skinnner's most widely acclaimed work, is based on a system of both positive and negative reinforcement.

Operant Behaviour and ConditioningWhile it is commonly known that behaviour is affected by its consequences, Skinner's theory of operant conditioning further states that the process does not require repeated efforts, but is instead an immediate reaction to a familiar stimulus. In an experiment with a rat using food as a reward (which would work for many of us, as well!), the rat was placed in a box and over the course of a few days, food was occasionally delivered through an automatic dispenser. Before long, the rat approached the food tray as soon as the sound of the dispenser was heard, clearly anticipating the arrival of more food. In the next step of the experiment, researchers raised a small lever on the wall of the box and when the rat touched it, the food dispenser provided a snack. After the first self-induced meal, the rat repeatedly touched the lever in order to get more food (smart rat!). To the hungry rodent, the sound of the dispenser became a reinforcer when it was first associated with feedings and continued to be so until after a while, researchers stopped providing food when the lever was pressed. Soon after that, the rat stopped touching the lever.

Positive and Negative ReinforcersReinforcers can be positive or negative and both are used to strengthen behaviour. Unlike animals, humans (the big ones as well as the little ones) often respond to verbal operants, taking advice, listening to the warnings of others, and obeying given rules and laws, even without having personally experienced any negative consequences from disobeying. The knowledge of what could happen if

certain behaviours are chosen can be enough to keep us from acting in certain ways. Although this isn't always the case, with many lessons being learned "the hard way," the ability to benefit from the experiences of others as examples is a uniquely human characteristic.

One of the aspects important to human behaviour, though, is the feelings associated with behaviour that is controlled by conditioning. When previous behaviours have been rewarded, children are likely to repeat those behaviours happily and willingly, feeling that they are doing what they 'want' to be doing. If, on the other hand, children choose behaviours in order to avoid a repeat of negative reinforcement, they may behave appropriately, but will be inclined to feel that their freedoms are being squelched. In reality, the actual freedom still exists, of course. Children, like the rest of us, are free to behave in any manner that we choose, as long as we are willing to accept the consequences of our actions.

Behaviour ModificationBehaviour modification typically consists of changing the consequences of an action or applying new consequences to guide behaviour. In the past, most parents chose to control the behaviour of their children by using negative reinforcement, that is, misbehaviour or disregarding house rules resulted in punishments. Today, many parents (and even school systems and other childhood authorities) are inclined to provide positive reinforcement to encourage good behaviour, reserving negative reinforcement techniques only as a last resort. While the results are not usually as immediate, they are typically seen as healthier, providing children with appropriate behavioural guidelines while allowing them their dignity.

Applying Behaviour Modification Obviously, it benefits both children and their parents when positive reinforcement techniques are chosen as a means of guiding children's behaviours, making for a more pleasant and respectfully run household. Even babies and very young children respond well to a system where rewards exists, repeating behaviours when they elicit big smiles and hugs from Mum and Dad. As children grow, using positive reinforcement to encourage appropriate behaviour can help parents to encourage their kids continued cooperation.