Relying on his associated reflex, he wanted to discover how far he could proceed on a purely objective basis. He claimed that he discovered the subject matter thoroughly without using any such terms as sensation, feeling, or thought.
Pavlov had made a dog his subject in the study of physiology of digestion. He was surprised to see that the sight of a person or the sound of his footsteps was a stimulus for the reflex flow of saliva from the dog’s mouth.
He could understand that the food in the mouth was a natural stimulus. He concluded that the sight of the person or the sound of his footsteps must have become attached to the response by prolonged experiment as a preliminary signal.
Pavlov considered such a capacity to be very important in the process of an animal’s adaptation to his physical environment. He also believed that he showed a new path to the experimental study of the higher brain functions.
He called the reflex as ‘conditioned reflex,’ because the response had become attached to some substitute for the natural stimulus.
From all his experiments,” Pavlov reached a theory of the functions of the brain. To Pavlov the brain has two inclusive functions. Firstly, it has a set of analyzers on the sensory side which pick out particular stimuli from the mass of physical motives.
In this respect, the brain may be taken as analogous to a radio-receiving set. The brain function on the motor side consists of ‘conditioned reflexes.’ All learned and even complex human behaviours consist of ‘conditioned reflexes.
‘It is the cerebrum which controls conditioning. With all these, Pavlov tries to prove that the key to the understanding of behaviour lies entirely with physiology. He regards Thorndike’s experiments on animal learning, too, quite sane to his own line of study.
Conditioned reflex occupied a very dominating position in American behaviorisms. By 1924, Watson regarded ‘conditioned reflex’ as key to all habit formation. But he did not appear to be fully convinced in this matter.