Dfyjkt

Walter Bradford Cannon
Born	(1871-10-19)October 19, 1871 Prairie du Chien, Wisconsin
Died	October 1, 1945(1945-10-01) (aged 73) Franklin, New Hampshire
Nationality	American
Education	Harvard College (1896) Harvard Medical School (1900, M.D.)
Known for	Homeostasis Fight or flight X ray experiments Cannon–Bard theory Voodoo death
Spouse(s)	Cornelia James Cannon
Awards	Fellow of the Royal Society,[1]Member of the National Academy of Sciences, USA Member of National Academy of Sciences, USSR
Scientific career
Fields	Physiology
Institutions	Harvard Medical School

Walter Bradford Cannon (October 19, 1871 – October 1, 1945) 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. A Review of General Psychology survey, published in 2002, ranked Cannon as the 81st most cited scholar of the 20th century in technical psychology journals, introductory psychology textbooks, and survey responses.^[2][3]

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.^[4] His sister Ida Maud Cannon (1877-1960) because a noted hospital social worker at Massachusetts General Hospital.

In his autobiography The Way of an Investigator, Cannon counts himself among the descendents 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 (philosopher), and James Freeman Clarke. Cannon's curiosity also led him to Thomas Henry Huxley, John Tyndall, George Henry Lewes, and William Kingdon Clifford.^[5] A high school teacher, Mary Jeannette Newson, became his mentor. "Miss May" Newson motivated and helped him take his academic skills to Harvard University.^[6]

In 1896, his first year at Harvard Medical School, he started working in Bowditch's Lab,^[7] and 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.^[8] He was a close friend of the physicist G. W. Pierce; they founded the Wicht Club with other young instructors for social and professional purposes. In 1906 Cannon became Higginson Professor and chairman of the Department of Physiology at Harvard Medical School, a position he held until 1942. From 1914 to 1916 he was also President of the American Physiological Society.^[7]

He was married to Cornelia James Cannon, a best-selling author and feminist reformer. Although not mountaineers, during their honeymoon in Montana the couple were the first, on July 19, 1901, to reach the summit of the unclimbed southwest peak (2657 m or 8716 ft) of Goat Mountain, between Lake McDonald and Logan Pass in what is now Glacier National Park. The peak was subsequently named Mount Cannon by the United States Geological Survey^[9] The couple had five children. One son was Dr. Bradford Cannon, a military plastic surgeon and radiation researcher. The daughters are Wilma Cannon Fairbank (Mrs. John K. Fairbank), Linda Cannon Burgess, Helen Cannon Bond and Marian Cannon Schlesinger, a painter and author living in Cambridge, Massachusetts.

Walter Cannon died on October 1, 1945 in Franklin, New Hampshire.^[10]

Work

Walter Bradford Cannon

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. 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.^[7]

In 1945 Cannon summarized his career in physiology by describing his focus at different ages:^[11]

• Age 26 – 40: digestion and the bismuth meal


• Age 40 – 46: bodily effects of emotional excitement


• Age 46 – 51: wound shock investigations


• Age 51 – 59: stable states of the organism


• Age 59 – 68: chemical mediation of nerve impulses (collaboration with Arturo Rosenblueth)


• Age 68 + : chemical sensitivity of nerve-isolated organs

Scientific contributions

Use of salts of heavy metals in X-Rays

He was one of the first researchers to mix salts of heavy metals (including bismuth subnitrate, bismuth oxychloride, and barium sulfate) into foodstuffs in order to improve the contrast of X-ray images of the digestive tract. The barium meal is a modern derivative of this research.

Fight or flight

In 1915, he coined the term fight or flight to describe an animal's response to threats in Bodily Changes in Pain, Hunger, Fear and Rage: An Account of Recent Researches into the Function of Emotional Excitement.^[12] He asserted that not only physical emergencies, such as blood loss from trauma, but also psychological emergencies, such as antagonistic encounters between members of the same species, evoke release of adrenaline into the bloodstream.

As per Cannon, adrenaline exerts several important effects in different body organs, all of which, from Cannon’s point of view, maintain homeostasis in fight-or-flight situations.^[13] For example, in the skeletal muscle of the limbs, adrenaline relaxes blood vessels, increasing local blood flow. Adrenaline constricts blood vessels in the skin, minimizing blood loss from physical trauma. Adrenaline also releases the key metabolic fuel, glucose, by the liver into the bloodstream, etc.
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

As a military physician in World War I he discovered that the blood of shocked men was acidic.^[14] As a member of the British Medical Research Council's Special Committee on Shock and Allied Conditions he advocated treating shocked wounded by infusing sodium bicarbonate to neutralize the acid. He and William Bayliss infused acid into an anesthetized cat, which died. However, a second trial done with Bayliss and Henry Dale failed to produce shock. Shock was successfully treated by infusing saline containing some larger molecules.

Homeostasis

He developed the concept of homeostasis from the earlier idea of Claude Bernard of milieu interieur, and popularized it in his book The Wisdom of the Body,1932. Cannon presented four tentative propositions to describe the general features of homeostasis:

1. Constancy in an open system, such as our bodies represent, requires mechanisms that act to maintain this constancy. Cannon based this proposition on insights into the ways by which steady states such as glucose concentrations, body temperature and acid-base balance were regulated.


2. 
   Steady-state conditions require that any tendency toward change automatically meets with factors that resist change. An increase in blood sugar results in thirst as the body attempts to dilute the concentration of sugar in the extracellular fluid.


3. The regulating system that determines the homeostatic state consists of a number of cooperating mechanisms acting simultaneously or successively. Blood sugar is regulated by insulin, glucagons, and other hormones that control its release from the liver or its uptake by the tissues.


4. Homeostasis does not occur by chance, but is the result of organized self-government.

The Sympathoadrenal System

Cannon’s proposed the existence and functional unity of the sympathoadrenal (or “sympathoadrenomedullary” or “sympathico-adrenal”) system. He theorized that the sympathetic nervous system and the adrenal gland work together as a unit to maintain homeostasis in emergencies. To identify and quantify adrenaline release during stress, beginning in about 1919 Cannon exploited an ingenious experimental setup. He would surgically excise the nerves 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 in 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 infer further 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 he formally proposed that the sympathetic nervous system uses the same chemical messenger—adrenaline—as does the adrenal gland. Cannon’s notion of a unitary sympathoadrenal system persists to this day. 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

Cannon developed the Cannon-Bard theory with physiologist Philip Bard to try to explain why people feel emotions first and then act upon them.

Dry mouth

He put forward the Dry Mouth Hypothesis, stating that people get thirsty because their mouths get dry. He did an experiment on two dogs. He made incisions in their throats and inserted small tubes. Any water swallowed would go through their mouths and out by the tubes, never reaching their stomachs. He found out that these dogs would lap up the same amount of water as control dogs.

Publication

Cannon wrote several books and articles.

• 1910, A Laboratory Course in Physiology, Harvard University Press 6th ed. 1927.


• 1910, 'Medical Control of Vivisection'
  


• 1911, The Mechanical Factors of Digestion
  


• 1915, Bodily Changes in Pain, Hunger, Fear and Rage
  


• 1920, Bodily Changes in Pain, Hunger, Fear and Rage (2 ed.)
  


• 1923, Traumatic Shock
  


• 1926, 'Physiological Regulation of Normal States'


• 1931, Lazaro in the pueblos: the story of Antonio de Espejo's expedition into New Mexico
  


• 1932, The Wisdom of the Body
  


• 1933, Some modern extensions of Beaumont's studies on Alexis St. Martin
  


• 1937, Digestion and Health
  


• 1937, Autonomic Neuro-effector Systems, with Arturo Rosenblueth
  


• 1942, '"Voodoo" Death'


• 1945, The Way of an Investigator: a scientist's experiences in medical research
  

References

Further reading

• Benison, Saul A., Clifford Barger, Elin L. Wolfe (1987) Walter B. Cannon: The Life and Times of a Young Scientist.
  ISBN 0674945808
  


• Cannon, Bradford. "Walter Bradford Cannon: Reflections on the Man and His Contributions". International Journal of Stress Management, vol. 1, no. 2, 1994.


• Kuznick, Peter. "The Birth of Scientific Activism". Bulletin of the Atomic Scientists, December 1988


• Schlesinger, Marian Cannon. Snatched from Oblivion: A Cambridge Memoir. Boston: Little, Brown and Company, 1979.


• Wolfe, Elin L., A. Clifford Barger, Saul Benison (2000) Walter B. Cannon, Science and Society.
  ISBN 0674002512
  

External links

Wikimedia Commons has media related to Walter Bradford Cannon.

• 
  Works by or about Walter Bradford Cannon at Internet Archive
  


• 
  6th APS President at the American Physiological Society


• 
  Walter Bradford Cannon: Experimental Physiologist: 1871-1945 - biography at Harvard Square Library


• 
  Chapter 9 of Explorers of the Body, by Steven Lehrer (contains information about X ray experiments)


• 
  The Walter Bradford Cannon papers can be found at The Center for the History of Medicine at the Countway Library, Harvard Medical School.


• 
  Walter Bradford Cannon, Homeostasis (1932)