B. F. SKINNER

1904 - 1990

Burrhus Frederic Skinner was born March 20, 1904, in Pennsylvania. He received his BA in English from Hamilton College, New York. He aspired to be a writer, but had little luck in that respect. So in 1930 he returned to school and received his Masters from Harvard and his Ph.D. in 1931.

In 1948, he was invited to teach at Harvard, where he was very active and involved in research. He also guided doctoral candidates and wrote many books on psychology. However, Skinner is best known for his experiments on operant conditioning.

B. F. Skinner’s theory is based on the idea of learning through rewards and punishments. Skinner believed that “changes in behavior are the result of an individual's response to events (stimuli) that occur in the environment. When a particular Stimulus-Response pattern is reinforced (rewarded or punished), the individual is conditioned to respond.” The reinforcer can be both positive and/or negative. A good grade, praise, or the withdrawal of a positive reinforcer can strengthen the desired response.

Skinner’s experiment involved a rat in a cage that learned a certain behavior based on both positive and negative reinforcers. Basically the rat was placed in a special cage, a “Skinner box” that had a pedal on one wall that, when pressed, would release a food pellet into the cage. At first, the rat accidentally pressed the bar and a food pellet fell into the cage. The rat soon realized that peddling at the bar released the food pellets. “A behavior followed by a reinforcing stimulus results in an increased probability of that behavior occurring in the future.”

The he asked “What if you don’t give the rat any more pellets?” After a few unsuccessful tries, the rat stopped pressing the bar. He did not get the result he hoped for. “This is called extinction of the operant behavior. A behavior no longer followed by the reinforcing stimulus results in a decreased probability of that behavior occurring in the future.”

Then Skinner turned the pellet machine back on. The rat quickly began to push the bar again, bringing the behavior back into existence. It was much easier and quicker for the rat to learn the behavior than the first time. “This is because the return of the reinforcer takes place in the context of a reinforcement history that goes all the way back to the very first time the rat was reinforced for pushing on the bar.”

Related Theories/Theorists:

Ivan Pavlov: Pavlov’s dogs are a famous example of conditioned behavior. Pavlov’s dogs were conditioned to salivate when they heard the tone of a metranome. As a result of hearing that sound exactly before they were given food, the dogs would salivate anytime they heard the sound. Basically the external stimuli (the sound) caused the behavior (salivate) because they thought they would be rewarded.

Edward Thorndike: Thorndike is know for his theory of the law of effect, which was based on how cats learned to escaped from puzzle boxes. He trained the cats to escape through rewarding them immediately upon escape. Through his experiments, he concluded that the more satisfactory the outcome, the more likely one is to repeat the act; the more unsatisfactory, the more one is likely to avoid the act.

Albert Bandura: Bandura’s theory was formed by experimenting with Bobo Dolls. He filmed a woman beating up a Bobo doll and then showed it to a group of Kindergarteners, who very quickly copied the behavior they witnessed and began to beat up the doll as well. He continued the experiment in many variations, in all cases the children coping the behavior they witnessed. He added rewards and punishments to the experiments to further encourage the children to copy and continue the behavior. His theory was based on four components:

1. Attention

2. Retention

3. Reproduction

4. Motivation

These psychologists along with many others all researched and experimented with behavioral and cognitive psychology. Their theories were based on the behavior and learning of individuals based on some type of reward or punishment system. While their theories and experiments varied somewhat, the main idea remained the same. If an individual’s act is rewarded then the act will continue; if the individual’s act is punished or the reward is withheld, then the act will stop.