Several types of learning exist. The most basic form is associative learning, i.e., making a new association between events in the environment. There are two forms of associative learning: classical conditioning (made famous by Ivan Pavlov’s experiments with dogs) and operant conditioning.Pavlov’s Dogs. In the early twentieth century, Russian physiologist Ivan Pavlov did Nobel prize-winning work on digestion.hen the bell becomes a conditioned stimulus (CS) which produces the conditioned response (CR) of salivation after repeated pairings between the bell and food. John B. Watson: Early Classical Conditioning with Humans. John B. Watson further extended Pavlov’s work and applied it to human beings.