Operant Conditioning Experiments
Psychology recognizes two main types of conditioning: classical conditioning and operant conditioning. Classical conditioning is basically associative conditioning, where a subject learns to associate a certain event with a known outcome; this is evidenced in psychologist Ivan Pavlov's research, where dogs learned to associate food with a ringing bell, eventually causing the dogs to unconsciously produce saliva at the sound of the bell. Operant conditioning, in contrast, involves the subject learning that his oe her action can cause a specific reaction, reward or consequence or at least know that their actions increase the probability of that reward or consequence; this is often also called positive or negative reinforcement.
With operant conditioning, the terms positive and negative reinforcement do not necessarily refer to whether the outcome is desired, but rather, positive is the addition of a stimulus and negative is the subtraction of a stimulus. Thus, positive reinforcement is the term given when operant conditioning involves a subject learning to do something in order to receive a reward. For example, if a rat gets a piece of cheese every time that it steps on a certain button, this is positive reinforcement.
Similarly, negative reinforcement refers to a specific action stopping a negative consequence. For example, if a rat's cage is being bombarded with loud music, the rat may learn that pushing another lever shuts off the music. In the 1930s, psychologist B.F. Skinner was the first to conduct serious research in this area, using his Skinner boxes to condition rats to press one lever for a reward, but avoid another lever, which would give a punishment.
In operant conditioning, the reinforcer is the change in the environment of the subject that happens based upon the subjects action. Both positive and negative reinforcement can be used intentionally, with a human controlling the reinforcer. But they can also be controlled naturally, with something in the environment applying the reinforcer. For example, if a child reaches for a lamp and touches a hot light bulb, this is negative reinforcement, where the environment has controlled the reinforcer; the bulb was hot, the child was hurt by it and now the child is less likely to repeat the action.
By contrast, imagine that the child looks at the light bulb; he or she then looks at a parent and points to the light bulb, saying, "hot." The parent, impressed, praises the child for knowing it is hot and for not touching it. This positive reinforcement teaches the child to look at the light, but not touch it.
Skinner asserted that this conditioning could be used to encourage positive actions and discourage negative actions in both humans and animals. He also noted that these learned actions would eventually stop if the reward or consequence stopped. Skinner called this extinction.