Ivan Pavlov was a Russian behaviorist who was influenced by Charles Darwin's theory of evolution. Pavlov's most famous theory of behaviorism was called Classical Conditioning. He used a simple demonstration to show how classical conditioning works. Pavlov used a dog as his subject. He rang a bell prior to conditioning the dog and got no response from it. Then he rang a bell a few seconds prior to feeding the dog. This action, known as conditioning, was repeated until the dog would respond to just the ringing of the bell (without food) by salivating.
John B. Watson was an American behavioral psychologist. Watson took Pavlov's idea of classical conditioning and applied it to humans. He believed that, with the exception of extreme states of love and rage, human behavior is created through conditioning. That is, as a reaction to environmental stimuli.
Watson used a human baby to prove his point. For this famous experiment, Watson used a nine-month-old baby named Little Albert. Watson conditioned Little Albert to have extreme responses to specific stimuli. Watson showed the child a white rabbit---a stimulus that generally does not elicit a strong emotional response. He then showed the infant the rabbit along with a surprisingly loud, scary noise, which caused fear in the child. The child then learned to associate the bunny with fear, and would react by becoming upset merely at the sight of the rabbit, without the presence of the loud noise.
B.F. Skinner was an American-born psychologist who developed the theory of Operant Conditioning. Skinner believed that all behavior is created through environmental stimuli, through a process of rewards and punishments. Skinner did not believe in the possibility of processes that occurred exclusively in the mind.
According to Skinner, there are four mechanisms that reinforce certain types of behavior. These can be demonstrated using a classroom scenario. Positive reinforcement is the mechanism in which a person is given a reward for doing something correctly. For instance, a teacher gives good grades to reinforce learning. With negative reinforcement, an undesirable situation is reversed, for example, allowing a student to be excused from writing a final because of good work throughout the term. Extinction is when behavior is ignored. For instance, if students are misbehaving and the teacher ignores it, it should disappear on its own accord. Finally, punishment is when behaviors are responded to with undesirable consequences. Creating consequences for students who are tardy is a form of punishment.