The resignation of John B. Watson from the world of academic psychology was the reason for psychologists and behaviorists to propose new forms of learning, beyond classical learning. The most important of the behavioral theories was functional addiction learning, proposed by Burrhus Frederic Skinner, known as B.F. Skinner.

This theory opposes the already existing psychoanalytic movement that mainly studied inner mental functions. For this reason, it is based on the study of observable behavior as it considers that this is much more effective and immediate. He also states that classical addictive learning is too simplistic to be able to explain clearly the complex human personality.

His research was based on the field of learning and behavior and especially on the study of human behavior and how an creature reacts when it is placed in a particular environment. Reactions of behavior were named by him as functional and for this he is considered the father of functional addictive learning. 

The formulation of this theory was mainly conducted by experimenting with animals and, to achieve his purpose, used a special box known as "Skinner Box" to perform experiments on rats. He initially placed a hungry rat in the box and noticed that while initially it was inactive then it began to adapt to the new environment and explore it. So it discovered a lever where, by pressing, food fell into the box and this continued for several times, resulting in the next time it was left in the box it immediately pushed the lever. In this way it seemed that the reward in practice prompted the rat to move more and more often the lever, and this aid worked positively on its hunger.

In another experiment, Skinner attempted to explain the negative reinforcement. So he placed a rat in a chamber in a similar way, but in that case the rat was not hungry but Skinner put it in unpleasant electricity current. When the rat felt this negative stimulus began to move desperately around the box and at some point hit the lever, where the stream of unpleasant current was seized immediately. So very easily after some attempts the rat deliberately pushes the lever in order to avoid the unpleasant stimulus. Here we can see the results of the negative reinforcement, in which case the rat resorts to direct lever pressure to get rid of the unpleasant negative current.

Skinner's fundamental theory for the time is that, unlike existing theories, he states that “a particular behavior is not dependent on the consequences to follow, but on the consequences that have already been followed by such behavior in the past.” Also he reports that each reaction has different types of reinforcement such as: physical reinforcements, social reinforcements, negative or aberrant reinforcements, while Skinner's collaborative learning is characterized by positive reinforcement, negative reinforcement, escape learning, and eventually indirect punishment (social isolation, interruption of privileges). This theory finds today too many uses in the classroom and in the school environment.

This theory, like any theory, has been criticized mainly for not taking into account the internal processes of an organism but also for the fact that the intensity of the stimuli depends anyway on the subject. He also was criticized for the fact that mice and pigeons are not human beings, so these results should be generalized with great caution.