erences

erences . In classical conditioning, the experimenter controls the occurrence of US, while in operant conditioning the occurrence of the reinforcer is under the control of the organism that is learning. Thus, for US in classical conditioning the organism remains passive, while in operant conditioning the subject has to be active in order to be reinforced. .

In the two forms of conditioning, the technical terms used to characterise the experimental proceedings are different. Moreover what is called reinforcer in operant conditioning is called US in classical conditioning. An US has two functions. In the beginning it elicits the response and also reinforces the response to be associated and elicited later on by the CS.

reinforcement , extinction or non-occurrence of learned response, generalisation of learning to other stimuli under some specifiable conditions, discrimination between reinforcing and non-reinforcing stimuli, and spontaneous recovery . Reinforcement Reinforcement is the operation of administering a reinforcer by the experimenter. Reinforcers are stimuli that increase the rate or probability of the responses that precede. We have noted that reinforced responses increase in rate, while non-reinforced responses decrease in rate.

A positive reinforcer increases the rate of response that precedes its presentation. Negative reinforcers increase the rate of the response that precedes their removal or termination. The reinforcers may be primary or secondary. A primary reinforcer is biologically important since it determines the organism’s survival (e.g., food for a hungry organism).

A secondary reinforcer is one which has acquired characteristics of the reinforcer because of the organism’s experience with the environment. We frequently use money, praise, and grades as reinforcers. They are called secondary reinforcers . Systematic use of reinforcers can lead to the desired response.

Such a response is shaped by reinforcing successive approximations to the desired response. Extinction Extinction means disappearance of a learned response due to removal of reinforcement from the situation in which the response used to occur. If the occurrence of CS-CR is not followed by the US in classical conditioning, or lever pressing is no more followed by food pellets in the Skinner box, the learned behaviour will gradually be weakened and ultimately disappear. Learning shows resistance to extinction .

It means that even though the learned response is now not reinforced, it would continue to occur for sometime. However, with increasing number of trials without reinforcement, the response strength gradually diminishes and ultimately it stops occurring. How long a learned response shows resistance to extinction depends on a number of factors. It has been found that with increasing number of reinforced trials resistance to extinction increases and learned response reaches its highest level.

At this level performance gets stabilised. After that the number of trials do not make a difference in It is an interesting phenomenon, which is a result of an interaction between the two forms of conditioning. Learned helplessness underlies psychological cases of depression. Seligman and Maier demonstrated this phenomenon in a study on dogs.

First, they subjected dogs to sound (CS) and electric shock (US) using classical conditioning procedure. The animal had no scope to escape or avoid the shock. This pairing was repeated a number of times. Then the dogs were subjected to shock in an operant conditioning procedure.

The dogs could escape the shock by pressing their heads against the wall. After having experienced inescapable shock in the Pavlovian contingency, the dog failed to escape or avoid shock in the operant conditioning procedure. The dog just .