Walter Bradford Cannon


Walter Bradford Cannon was an American physiologist, professor and chairman of the Department of Physiology at Harvard Medical School. He coined the term "fight or flight response", and he expanded on Claude Bernard's concept of homeostasis. He popularized his theories in his book The Wisdom of the Body, first published in 1932.

Life and career

Cannon was born on October 19, 1871, in Prairie du Chien, Wisconsin, the son of Colbert Hanschett Cannon and his wife Wilma Denio. His sister Ida Maud Cannon became a noted hospital social worker at Massachusetts General Hospital.
In his autobiography The Way of an Investigator, Cannon counts himself among the descendants of Jacques de Noyon, a French Canadian explorer and coureur des bois. His Calvinist family was intellectually active, including readings from James Martineau, John Fiske, and James Freeman Clarke. Cannon's curiosity also led him to Thomas Henry Huxley, John Tyndall, George Henry Lewes, and William Kingdon Clifford. A high school teacher, Mary Jeannette Newson, became his mentor. "Miss May" Newson motivated him and helped him take his academic skills into Harvard University in 1892.
Upon finishing his undergraduate studies in 1896, he entered Harvard Medical School. He started using x-rays to study the physiology of digestion while working with Henry P. Bowditch. In 1900 he received his medical degree.
After graduation, Cannon was hired by William Townsend Porter at Harvard as an instructor in the Department of Physiology while continuing his study of digestion. Cannon was promoted to an assistant professor of physiology in 1902. He was a close friend of the physicist, G. W. Pierce, and together they founded the Wicht Club with other young instructors for social and professional purposes. In 1906, Cannon had succeeded Bowditch as the Higginson Professor and chairman of the Department of Physiology at Harvard Medical School until 1942. From 1914 to 1916, Cannon was also President of the American Physiological Society.
He was married to Cornelia James Cannon, a best-selling author and feminist reformer. On July 19,1901, during their honeymoon in Montana, they were the first people to reach the summit of the unclimbed southwest peak of Goat Mountain, between Lake McDonald and Logan Pass. That area is now Glacier National Park. The peak was subsequently named, Mount Cannon, by the United States Geological Survey The couple had five children; A son, Dr. Bradford Cannon, a military plastic surgeon and radiation researcher. The daughters were Wilma Cannon Fairbank, Linda Cannon Burgess, Helen Cannon Bond and Marian Cannon Schlesinger, a painter and author living in Cambridge, Massachusetts.
His philosophy of life may be inferred by his actions and his statements. Born into a Calvinistic family, he broke away from religious authoritarianism and achieved an independence from his prior dogma. Later in life he states that naturally occurring events are what makes for a useful end. He took on the role of a naturalist where believed that the body and mind are inseparable as an organismic unit. The explanations of his work should enable man to live more wisely, happily, and intelligently without the interjection of supernatural interference.
Walter Cannon died on October 1, 1945 in Franklin, New Hampshire.

Work

Walter Cannon began his career in science as a Harvard undergraduate in the year 1892. Henry Pickering Bowditch, who had worked with Claude Bernard, directed the laboratory in physiology at Harvard. Here Cannon began his research: he used the newly discovered x-rays to study the mechanism of swallowing and the motility of the stomach. Within his first experiments he was able to watch the course of a button down a dog's esophagus. He says in his autobiography, The Way of an Investigator, “The whole purpose of my effort was to see the peristaltic waves to learn their effects. Only after some time did I note that the absence of activity was accompanied by signs of perturbation, and when serenity was restored the waves promptly reappeared.”
He demonstrated deglutition in a goose at the APS meeting in December 1896 and published his first paper on this research in the first issue of the American Journal of Physiology in January 1898.
In 1945 Cannon summarized his career in physiology by describing his focus at different ages:
;Use of salts of heavy metals in X-Rays
;Fight or flight
As per Cannon, adrenaline exerts several important effects in different body organs, all of which maintain homeostasis in fight-or-flight situations. For example, in the skeletal muscle of the limbs, adrenaline relaxes blood vessels which increases local blood flow. Adrenaline constricts blood vessels in the skin and minimizes blood loss from physical trauma. Adrenaline also releases the key metabolic fuel, glucose, from the liver into the bloodstream.
However, the fact that aggressive attack and fearful escape both involve adrenaline release into the bloodstream does not imply an equivalence of “fight” with “flight” from a physiological or biochemical point of view.
;Wound shock
;Homeostasis
;The Sympathoadrenal System
Cannon proposed the existence and functional unity of the sympathoadrenal system. He theorized . To identify and quantify adrenaline release during stress, beginning in about 1919 Cannon exploited an ingenious experimental setup. He would surgically excise the nerves by supplying the heart of a laboratory animal such as a dog or cat. Then he would subject the animal to a stressor and record the heart rate response. With the nerves to the heart removed, he could deduce that if the heart rate increased in response to the perturbation, then the increase in heart rate must have resulted from the actions of a hormone. Finally, he would compare the results of an animal with intact adrenal glands with those in an animal from which he had removed the adrenal glands. From the difference in the heart rate between the two animals, he could further infer that the hormone responsible for the increase in heart rate came from the adrenal glands. Moreover, the amount of increase in the heart rate provided a measure of the amount of hormone released. Cannon became so convinced that the sympathetic nervous system and adrenal gland functioned as a unit that in the 1930s that he formally proposed that the sympathetic nervous system uses the same chemical messenger—adrenaline—as does the adrenal gland. . Researchers in the area have come to question the validity of the notion of a unitary sympathoadrenal system, although clinicians often continue to lump together the two components.
;Cannon-Bard theory
;Dry mouth

Publication

Cannon wrote several books and articles.