Cannon, Walter Bradford

Cannon, Walter Bradford, 1871–1945, American physiologist. While still a medical student at Harvard, Cannon was the first to demonstrate (1897) that bismuth could be utilized as a contrast medium in the roentgenologic examination of the gastrointestinal tract. His interest in the physiological effects of emotional stimuli, especially on digestion, led to the publication in 1919 of Bodily Changes in Pain, Hunger, Fear and Rage. He later concentrated his attention on the adrenal glands and by 1929 was emphasizing the emergency function of these glands in meeting vital threats to the body and in maintaining the equilibrium of the many processes of the organism. In 1932, while professor of physiology at Harvard, he introduced the important concept of homeostasis.