Work

Through the digestive process, the body extracts nourishment and energy from food. Ivan Pavlov studied the various processes of digestion, in part by exposing sections of a dog's intestinal canal through surgery. During the 1890s he identified ways in which different parts of the body, through the nervous system, affect movements in the intestinal canal as well as secretion of gastric juice and other secretions. He also pointed out the significance of psychic factors, such as hunger's ability to activate secretion of gastric juice. Furthermore, he demonstrated the sensitivity of gastric mucosae to various chemical substances.