Ivan Pavlov

(1849 - 1936)

Ivan Pavlov was a Russian physiologist whose research on the physiology of digestion led to the development of the first experimental model of learning, Classical Conditioning. Most of his research was gathered studying salivating dogs..

Pavlov was born on September 14, 1849, at Ryazan, Russia. Because he was born into a large family, poverty was always an issue. His father, Peter Dmitrievich Pavlov, was the village priest and young Ivan tended to the church property. Pavlov inherited many of his father's characteristics including a strong will to succeed.

The oldest sibbling, Ivan Pavlov was also among the healthiest. He began school at the Ryazan Ecclesiastical High School. Pavlov and his brothers eventually entered the Ryazan Ecclesiastical Seminary. At the Seminary, he planned to pursue a career in theology. However, after being introduced to the works of Charles Darwin and Ivan Sechenov, Pavlov decided to transfer to the University of St. Petersburg to gain knowledge about natural science. There, Pavlov gained great respect for a professor of physiology, Cyon. Due to Cyon's enthusiasm for physiology, he decided to become a physiologist during his third year. At that point, Pavlov started work as an assistant in a laboratory in which he earned 50 rubles a month.

Eventually, Pavlov's research on the physiology of digestion would earn him the Nobel Prize. As a skilled surgeon, he was able to implant small stomach pouches in dogs to measure the secretion of gastric juices produced when the dogs began to eat. With the help of his assistants, he was able to condition the dogs to salivate at the click of a metronome. As his work progressed, Pavlov established the basis for conditioned reflexes and the field of classical conditioning.

Time Line
September 14, 1894 Born in Ryazan, Russia
1870 Leaving his religious career, Pavlov enrolled to take a natural science course at the University of St. Pertersburg
1875 Graduated from the University of St. Pertersburg and took an assistantship from Cyon in his laboratory at the Military-Medical Academy; received the degree of Candidate of Natural Sciences
1876-78 Becomes an assistant in Ustimovich's laboratory
Summer of 1877 He spent time in Physiological Laboratory of Professor R. Heidenhain at Breslau
1879 Graduated from the Military-Medical Academy
1879 Completed third course of study at the Academy of Medical Surgery; awarded his first gold medal
1879-1904 Wrote for a volume in commemoration of the 25th Graduation Anniversary from the Military-Medical Academy
June 13, 1880 Proposed to Seraphima (Sara) Vasilievna karchevskaya
1880-84 Postgraduate study and research at the Academy
1881 Married Sara
1883 Discovered dynamic nerves of the heart and submitted thesis for the degree of Doctor of Medicine
April 24, 1884 Made a lecturer in physiology at the Military-Medical Academy
1885-86 Studied abroad June 15, 1890 Made chair and appointed professor of pharmacology in the Military-Medical Academy
1890 Appointed director of physiology department at the Institute of Experimental Medicine in St. Petersburg
June 13, 1891 Gained directorship of the Department of Physiology in the Institute of Experimental Medicine
1891-1900 Did most of his research on physiology of digestion at the Institute of Experimental Medicine
May 29, 1895 Appointed to Chair of Physiology until 1925
1897 Published his lectures entitled Lectures on the functions of the principal digestive glands
1901 Elected as a corresponding member of the Russian Academy of Sciences
1904 Received Nobel Prize in Physiology and Medicine for work on the physiology of the digestive glands
1907 Elected Academician of the Russian Academy of Sciences
1912 Given an honorary doctorate at Cambridge University
1915 Awarded the Order of the legion of Honour (Medical Academy of Paris recommendation)
January 24, 1921 Awarded a special government decree signed by Lenin
1924 Resigned from professorship at the Military-Medical Academy
1935 Youngest son, Vsevolod, died
1935 Government built a laboratory for Pavlov with his chief work on conditioned reflexes
1936 On February 27, Pavlov died in Leningrad


Bibliography
Babkin, B.P. (1949). Pavlov: A Biography. Toronto, Canada: The University of Chicago Press.

Hothersall, David. (1995). History of Psychology. New York: McGraw-Hill, Inc. pp. 239-253.
Morris, C.G., and Maisto, A.A. (1999). Understanding Psychology. 4th ed. New Jersey: Prentice Hall, Inc.
WEBSITES:
"Pavlov, Ivan Petrovich". Available: http://www.excite.com/reference/almanac/?id=A0158299 Provides the year of birth and death, birthplace, and career field of Pavlov.
"Ivan Petrovich Pavlov". Available: http://www.de.nobel.se/laureates/medicine-1904-1-bio.html Provides factual information about Pavlov's life both personal and career related.

Classical Conditioning (Pavlov)

Several types of learning exist. The most basic form is associative learning, i.e., making a new association between events in the environment. There are two forms of associative learning: classical conditioning (made famous by Ivan Pavlov’s experiments with dogs) and operant conditioning.

Pavlov’s Dogs

In the early twentieth century, Russian physiologist Ivan Pavlov did Nobel prize-winning work on digestion. While studying the role of saliva in dogs’ digestive processes, he stumbled upon a phenomenon he labeled “psychic reflexes.” While an accidental discovery, he had the foresight to see the importance of it. Pavlov’s dogs, restrained in an experimental chamber, were presented with meat powder and they had their saliva collected via a surgically implanted tube in their saliva glands. Over time, he noticed that his dogs who begin salivation before the meat powder was even presented, whether it was by the presence of the handler or merely by a clicking noise produced by the device that distributed the meat powder.

Fascinated by this finding, Pavlov paired the meat powder with various stimuli such as the ringing of a bell. After the meat powder and bell (auditory stimulus) were presented together several times, the bell was used alone. Pavlov’s dogs, as predicted, responded by salivating to the sound of the bell (without the food). The bell began as a neutral stimulus (i.e. the bell itself did not produce the dogs’ salivation). However, by pairing the bell with the stimulus that did produce the salivation response, the bell was able to acquire the ability to trigger the salivation response. Pavlov therefore demonstrated how stimulus-response bonds (which some consider as the basic building blocks of learning) are formed. He dedicated much of the rest of his career further exploring this finding.

In technical terms, the meat powder is considered an unconditioned stimulus (UCS) and the dog’s salivation is the unconditioned response (UCR). The bell is a neutral stimulus until the dog learns to associate the bell with food. Then the bell becomes a conditioned stimulus (CS) which produces the conditioned response (CR) of salivation after repeated pairings between the bell and food.

John B. Watson: Early Classical Conditioning with Humans

John B. Watson further extended Pavlov’s work and applied it to human beings. In 1921, Watson studied Albert, an 11 month old infant child. The goal of the study was to condition Albert to become afraid of a white rat by pairing the white rat with a very loud, jarring noise (UCS). At first, Albert showed no sign of fear when he was presented with rats, but once the rat was repeatedly paired with the loud noise (UCS), Albert developed a fear of rats. It could be said that the loud noise (UCS) induced fear (UCR). The implications of Watson’s experiment suggested that classical conditioning could cause some phobias in humans.

For more information, see:

Pavlov, I. P. (1927). Conditioned Reflexes: An Investigation of the Physiological Activity of the Cerebral Cortex. Translated and Edited by G. V.