Operant conditioning is the name coined by psychologist B.F. Skinner to a method of behavioural modification. Operant behaviour is so named because Skinner felt the environment influences behaviour and consequences of the behaviour reinforces the continued behaviour. Some refer to this idea as positive and negative reinforcement. There are four contexts of operant conditioning, including positive reinforcement, negative reinforcement, positive punishment and negative punishment. Each procedure uses the addition or subtraction of stimulus meant to modify behaviour.
Praise the child when desired behaviour is exhibited. Reinforce the behaviour you want out of the child with praise or a prize. Skinner's theory of operant behaviour states that a behaviour that is rewarded increases in frequency. The words "positive" and "negative" are not used in their usual sense here. Rather, positive refers to an addition of stimulus and negative refers to the subtraction of stimulus. When the child exhibits behaviour you want him to repeat, use positive reinforcement by adding a desired stimulus.
Punish students who engage in behaviour that is undesirable. Skinner called this positive punishment, which appears to be a misnomer. Positive punishment involves adding an aversive stimulation to get a desired response, at which point the aversive stimulation is removed. For the rowdy classroom with children who won't stop yelling, an air horn will be the aversive stimulation. When the classroom quiets down -- the desired response -- the air horn is silenced. This context is also called "punishment by contingent stimulation."
Use an aversive stimulus to prompt a desired behaviour. This is negative reinforcement, which means that the aversive stimulus continues until the desired behaviour is exhibited, at which point the aversive stimulus ceases. Whereas positive punishment seeks to stop an undesired behaviour that is already occurring, negative reinforcement seeks to initiate desired behaviour by the removal of the aversive stimulus when the behaviour is exhibited.
For example, the air horn used to quiet a rowdy classroom was positive punishment. For negative reinforcement the use of the air horn would be to prompt a desired response -- lining up for lunch or dismissal, say -- at which point the aversive stimulus is removed. This context is also referred to as the "escape" method.
Remove stimulus to modify behaviour using the negative punishment context. Negative punishment occurs when an undesired behaviour or response is followed by the removal of a stimulus. When a child misbehaves and the teacher removes his toy, the behaviour that prompted the removal of the toy should result in a decrease of that behaviour. This context is also called "punishment by contingent withdrawal." The promise of the return of the removed stimulus, the toy, is contingent on the change in the undesired behaviour.
Combine the use of all four contexts to shape the behaviour of the preschool students. An important key is to remain consistent in the rewarding of desired behaviour and in the punishing of undesired behaviour. Part of Skinner's theory includes the concept of "extinction," in which a behaviour that was previously reinforced is no longer present when the stimulus ceases.