Ivan Pavlov

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Ivan Petrovich Pavlov
Иван Петрович Павлов

Nobel Prize portrait, 1904
Born	September 14, 1849 Ryazan, Russia
Died	February 27, 1936 Leningrad, Soviet Union
Residence	Russian Empire Soviet Union
Nationality	Russian Soviet
Field	Physiologist, psychologist, physician
Institution	Military Medical Academy
Alma mater	Saint Petersburg University
Known for	Classical conditioning Transmarginal inhibition Behavior modification
Notable prizes	Nobel Prize in Physiology or Medicine
Religion	Russian Orthodox

Ivan Petrovich Pavlov (Russian: Иван Петрович Павлов) (September 14, 1849 – February 27, 1936) was a Russian physiologist, psychologist, and physician. He was awarded the Nobel Prize in Physiology or Medicine in 1904 for research pertaining to the digestive system. Pavlov is widely known for first describing the phenomenon now known as classical conditioning in his experiments with dogs.

Contents 1 Life and research 2 Reflex system research 3 Legacy 4 See also 5 References 6 External links

[edit] Life and research

Pavlov was born in Ryazan, Russia. He began his higher education as a seminary student, but dropped out and enrolled in the University of St. Petersburg to study the natural sciences. He received his doctorate in 1879.

In the 1890s, Pavlov was investigating the gastric function of dogs by externalizing a salivary gland so he could collect, measure, and analyze the saliva many had in response to food under different conditions. He noticed that the dogs tended to salivate before food was actually delivered to their mouths, and set out to investigate this "psychic secretion", as he called it. He decided that this was more interesting than the chemistry of saliva, and changed the focus of his research, carrying out a long series of experiments in which he manipulated the stimuli occurring before the presentation of food. He thereby established the basic laws for the establishment and extinction of what he called "conditional reflexes" — i.e., reflex responses, like salivation, that only occurred conditionally upon specific previous experiences of the animal. These experiments were carried out in the 1890s and 1900s, and were known to western scientists through translations of individual accounts, but first became fully available in English in a book published in 1927.

Pavlov was a dexterous operator who was compulsive about his working hours and habits. He would sit down to lunch at exactly 12 o'clock, he would go to bed at exactly the same time each evening and he would always leave Leningrad for Estonia on vacation on the same day each year. This behavior changed when his son Victor died in the White Army — after which he suffered from insomnia.

Unlike many pre-revolutionary scientists, Pavlov was highly regarded by the Soviet government, and he was able to continue his researches until he reached a considerable age. Pavlov himself was not favorable towards Marxism, but as a Nobel laureate he was seen as a valuable political asset.^[1][2]

After the murder of Sergei Kirov in 1934, Pavlov wrote several letters to Molotov criticizing the mass persecutions which followed and asking for the reconsideration of cases pertaining to several people he knew personally.

In later life he was particularly interested in trying to use conditioning to establish an experimental model of the induction of neuroses. He died in Leningrad. His laboratory in Saint Petersburg has been carefully preserved.

Conscious until his very last moment, Pavlov asked one of his students to sit beside his bed and to record the circumstances of his dying. He wanted to create unique evidence of subjective experiences of this terminal phase of life. The great scientific courage of Pavlov is exhibited by this story: he tried to learn, and to increase knowledge of physiology, even in his deathbed.^{[citations needed]}

[edit] Reflex system research

Pavlov contributed to many areas of physiology, neurology and psychology. Most of his work involved research in temperament, conditioning and involuntary reflex actions.

Pavlov performed and directed experiments on digestion which earned him the 1904 Nobel Prize in Physiology and Medicine ^[3] Experiments included surgically extracting portions of the digestive system from animals, severing nerve bundles to determine the effects, and implanting fistulas between digestive organs and an external pouch to examine the organ's contents. This research served as a base for broad research on the digestive system.

Further work on reflex actions involved involuntary reactions to stress and pain. Pavlov extended the definitions of the four temperament types under study at the time: phlegmatic, choleric, sanguine, and melancholic. Pavlov and his researchers observed and began the study of transmarginal inhibition (TMI), the body's natural response of shutting down when exposed to overwhelming stress or pain. This research showed how all temperament types responded to the stimuli the same way, but different temperaments move through the responses at different times. He commented "that the most basic inherited difference. .. was how soon they reached this shutdown point and that the quick-to-shut-down have a fundamentally different type of nervous system."^[4]

Carl Jung continued Pavlov's work on TMI and correlated the observed shutdown types in animals with his own introverted and extroverted temperament types in humans. Introverted persons, he believed, were more sensitive to stimuli and reached a TMI state earlier than their extroverted counterparts. This continuing research branch is gaining the name highly sensitive persons.

William Sargant and others continued the behavioral research in mental conditioning to achieve memory implantation and brainwashing.

[edit] Legacy

Interestingly, Pavlov's term "conditional reflex" ("условный рефлекс") was mistranslated from the Russian as "conditioned reflex", and other scientists reading his work concluded that since such reflexes were conditioned, they must be produced by a process called conditioning. As Pavlov's work became known in the West, particularly through the writings of John B. Watson, the idea of "conditioning" as an automatic form of learning became a key concept in the developing specialism of comparative psychology, and the general approach to psychology that underlay it, behaviorism. The British philosopher Bertrand Russell was an enthusiastic advocate of the importance of Pavlov's work for philosophy of mind.

Pavlov's research on conditional reflexes greatly influenced not only science, but also popular culture. The phrase "Pavlov's dog" is often used to describe someone who merely reacts to a situation rather than uses critical thinking. Pavlovian conditioning was a major theme in Aldous Huxley's dystopian novel, Brave New World, and also to a large degree in Thomas Pynchon's Gravity's Rainbow.

It is popularly believed that Pavlov always signaled the occurrence of food by ringing a bell. However, his writings record the use of a wide variety of stimuli, including whistles, metronomes, tuning forks, and a range of visual stimuli, in addition to ringing a bell.

Catania^[5] cast doubt on whether Pavlov ever actually used a bell in his famous experiments. Littman^[6] tentatively attributed the popular imagery to Pavlov’s contemporaries Vladimir Mikhailovich Bekhterev and John B. Watson, until Thomas^[7] found several references that unambiguously stated Pavlov did, indeed, use a bell.

[edit] See also

• Classical conditioning
• Behavior Modification
• Ryazan

[edit] References

1. ^ Ivan Pavlov. Retrieved on 2007-01-01.
2. ^ http://wwwa.britannica.com/eb/article-5560
3. ^ http://nobelprize.org/nobel_prizes/medicine/laureates/1904/press.html.
4. ^ Rokhin, L, Pavlov, I & Popov, Y. (1963) Psychopathology and Psychiatry, Foreign Languages Publication House: Moscow.
5. ^ Catania, A. Charles (1994); Query: Did Pavlov's Research Ring a Bell?, PSYCOLOQUY Newsletter, Tuesday, June 7, 1994
6. ^ Littman, Richard A. (1994); Bekhterev and Watson Rang Pavlov's Bell, Psycoloquy, Vol. 5, No. 49
7. ^ Thomas, Roger K. (1994); Pavlov's Dogs "dripped Saliva at the Sound of a Bell", Psycoloquy, Vol. 5, No. 80 http://www.cogsci.ecs.soton.ac.uk/cgi/psyc/newpsy?5.80 (accessed 2006-aug-22)

• Boakes, R. A. (1984). From Darwin to behaviourism. Cambridge: Cambridge University Press.
• Firkin, B. G.; & Whitworth, J. A. (1987). Dictionary of Medical Eponyms. Parthenon Publishing. ISBN 1-85070-333-7
• Pavlov, I. P. (1927). Conditioned Reflexes: An Investigation of the Physiological Activity of the Cerebral Cortex (translated by G. V. Anrep). London: Oxford University Press.
• Todes, D. P. (1997). "Pavlov's Physiological Factory," Isis. Vol. 88. The History of Science Society, p. 205-246.

[edit] External links

• PBS article
• Nobel Prize website biography of I. P. Pavlov
• Institute of Experimental Medicine article on Pavlov
• A comic strip about Pavlos' work, by Wulffmorghenthaler.
• Link to full text of Pavlov's lectures
• Link to a list of Pavlov's dogs with some pictures

Persondata
NAME	Pavlov, Ivan
ALTERNATIVE NAMES
SHORT DESCRIPTION	Physiologist, psychologist, physician
DATE OF BIRTH	September 14, 1849
PLACE OF BIRTH	Ryazan, Russia
DATE OF DEATH	February 27, 1936
PLACE OF DEATH	Leningrad, Soviet Union