Classical Conditioning

Classical Conditioning began as a study in digestion where Pavlov used dogs as subjects to investigate the interaction between salivation and the action of the stomach. He found that without salivation the stomach was not active. If food was produced the dogs would salivate. However, he began to notice that some of the dogs in his lab began to salivate before they were fed. He saw, too, that this occurred only in dogs that had been in the lab for some time (Lefrancois, 1995). A set of diagrams illustrate classical conditioning below

Unconditioned stimulus

The dog salivates when it sees steak (unconditioned response).

With this finding, Pavlov wanted to see if external stimuli could affect his process. He began by ringing a bell at the same time that he fed the dogs.

Neutral stimulus
Unconditioned stimulus
The dog salivates when it sees steak and hears the sound of the bell.

After a while the dogs who before only salivated when they saw or ate food, began to salivate when the bell was rung, even without food present.

Neutral stimulus has become conditioned
The dog eventually salivates when it hears the sound of the bell alone (conditioned response).

Pavlov called this a conditioned reflex as it was different to an innate reflex such as pulling a hand away from a flame, as it has to be learned. He called this learning process 'Classical Conditioning' http://www.pbs.org/wgbh/aso/databank/entries/bhpavl.html

The term used to describe the conditioning of actions involving glands or involuntary muscles is interoceptive conditioning (Lefrancois, 1995).

Pavlov's conditioned reflex experiments played a role in the development of behaviourist theory introduced by John Watson around 1913.

Higher Order Conditioning

Higher-Order Conditioning is a type of conditioning emphasized by Ivan Pavlov. It involves the modification of reaction to a neutral stimulus associated with a conditioned stimulus that was formerly neutral. An example of higher-order conditioning is outlined in the diagrams below .

When a random object is introduced when the bell is rung, the dogs continued to salivate.

Now conditioned stimulus
Random object(neutral stimulus)
The dog salivates when it hears the bell and sees the random object.

When the bell was taken away, and the new random object was used instead, the dogs continued to salivate. This indicates that the stimulus can be changed and that salivation will still occur.

Neutral stimulus
The neutral stimulus has been modified to make the dog salivate.




Webpage by M.Defryn, 2001