Learning helps us adapt to the surrounding environment. After living in a particular socio-cultural environment for some time, we learn the norms of the society and all that is expected of us and become responsible citizen and members of family and work organization. All this is possible on account of learning. We use learning to acquire various types of skills.

Psychologists, on the basis of studies on human beings and on animals, have tried to explain the process of learning. They have identified some procedures that are used in the acquisition of simple as well as complex responses. The two basic types of learning are classical conditioning and operant or instrumental conditioning. In addition, we have observational learning, verbal learning, concept learning, and skill learning.

Classical Conditioning: Learning through Association

Classical conditioning is also known as Pavolovian conditioning because it was discovered by a Russian scientist Ivan P. Pavlov who was interested in studying stimulus-response relationship. He worked with dogs. The animal was harnessed and food was presented to the dog by a laboratory assistant. Pavlov realized that the salivary response had been learned by the dog. He proceeded to study this type of learning in detail.

Pavlov presented to the dog a series of trials in which a tone (buzzer) was paired with food (biologically important stimulus). The learning trials consisted of pairing the tone, (Conditioned Stimulus or CS) with food (Unconditioned Stimulus or UCS). The tone presented was rather short (e.g., 10 secs) and the time interval between the tone and presentation of food, was between 2 to 3 minutes.

During the initial trials the dog salivated when the food was presented. Secretion of saliva to food is a natural response and, therefore, the saliva is called Unconditioned Response (UR). Later, the buzzer was presented first. It was followed by food. After some pairing trials of buzzer and food, the dog started salivation at the ringing of buzzer alone. The buzzer is called Conditioned Stimulus (CS) because the dog has been conditioned to salivate at the presentation of the buzzer itself. The secretion of saliva on the presentation of buzzer is called Conditioned Response (CR).

Originally the sound of the buzzer (CS) elicits only an orienting response (alerting response) and elicits salivation when the food is consistently presented in close association with the buzzes. Immediately after the buzzer is rung, the animal elicits salvation. This is called acquisition.

It has been found that if the buzzer (CS) is presented on each trial but the food (US) is not presented, extinction will take place. That is, the buzzer will no more elicit saliva (CR) and if it is continued for some time extinction will take place.

It has also been found that if a gap of some duration occurs after extinction and if the buzzer (CS) is again presented without food (US) the dog will salivate (produce CR) for a few trials. This recovery of CR after extinction is called spontaneous recovery.

Operant Conditioning: Modification of Behaviour through Reinforcement

If a child completes the home work she is praised (rewarded) by the parents and the child learns to perform the task. If the child breaks a plate, he or she is scolded (punished) and she will learn not to repeat the behaviour. This is called Operant Conditioning or instrumental conditioning. In other words, we learn to perform behaviours that produce positive outcomes and avoid behaviours that yield negative outcomes.

Operant conditioning is defined as a process through which organisms learn to repeat behaviours that produce positive outcomes or avoid or escape from the negative outcomes. B.F. Skinner is considered as the most influential psychologist advocating the role of operant conditioning in learning. He developed an experimental chamber (called Skinner Box) to study learning process in rats.

The chamber included a lever attached to the front wall. Pressing the lever is the response to be learned. The hungry rat is placed in the chamber and it starts doing random activity in it. After some time, the rat accidentally presses the lever and a pellet of food drops automatically in the plate and the rat eats it. After eating the pallet the rat again starts activity in the chamber. After some activity it again presses the lever and gets pellet (a reward).

Gradually the random activity changes to more specific activity around the lever. Finally, the rat learns that pressing the lever results in dropping of the food, a satisfying outcome. In other words the pressing of lever by the rat is instrumental in providing food (reinforcement). The response (pressing the lever) is reinforced and the behaviour is acquired or learned.

The pressing of lever by the rat is instrumental in getting the food, a satisfying consequence (positive reinforcement) and that is why this type of learning is also called instrumental learning. It is also called operant conditioning because the behaviour of rat or any organism is a kind of operation on the environment.