Operant conditioning uses reinforcement or punishment to increase or decrease a behavior. A behavior that is followed by a reinforcement will increase, whereas, a behavior that is followed by a punishment will decrease. This is known as the law of effect. An example of reinforcement is giving a child a piece of candy only after the child says "please." The candy reinforces, and thus increases, the chances of the child saying "please."
An example of punishment is rinsing a child's mouth out with soap after saying an undesirable word. The disgusting taste of soap decreases the behavior of saying the unacceptable word.
A primary reinforcer is any reinforcer that does not need to be learned. Reinforcers such as money or an award are known as secondary reinforcers. A primary reinforcer is biologically rooted, such as hunger, sleep, oxygen or sex. A secondary reinforcer is learned, such as money that can be used to exchange for a primary reinforcer.
Examples of primary reinforcers include food, water, sleep, oxygen and sex. Behavior that is followed by the satisfaction of these basic drives will increase. Using a biscuit to reward a dog for rolling over is an example of a primary reinforcer. A student receiving an A on a test for performing well is a secondary reinforcer because the symbol A cannot satisfy a biological drive.
According to Thorndike and Skinner, depriving an animal of a primary reinforcer, such as food, until a behavior is performed will significantly increase that behavior. A child who receives a toy or sweet after a tantrum is thrown will increase their acrimonious behavior.