(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. An illustrated review of Pavlov's experiments is available on the [Discovery
Web Site].
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.
Theory
Pavlov concluded that he was able to pair a neutral stimulus with an excitatory
one and have the neutral stimulus eventually elicit the response the was
associated with the original, unlearned reflex. In Classical Conditioning
terminology, an unconditioned stimulus (US) is an event that causes a response
to occur, which is referred to as the unconditioned response (UR). And, in
Pavlov's study with dogs, the food within the dog's mouth is the US, and the
salivation that results is the UR. Pavlov took a step further and added an
element known as the nonexcitatory, conditioned stimulus (CS), which is paired
with the US.
Pavlov used a metronome as the CS which he rang first, then fed the dogs. This
pairing would eventually establish the dog's conditioned response of salivating
to the sound of the metronome. After repeating this procedure several times,
Pavlov was able to remove the US (food) and by only ringing the bell the dogs
would salivate (CR). Since the bell alone now produced the unconditioned
response (salivation), the association had been established (Conditioned).
Pavlov continued to present the CS with any pairing with the US until the CR no
longer occurred. This elimination of the CR is known as extinction. However,
waiting a few days and then reintroducing ticking metronome resulted in the dogs
once again salivating to the CS. Pavlov termed this, spontaneous recovery.
Pavlov continued of the conditioned response. He replaced the metronome with
other stimuli for use as the CS. He conditioned the dogs using a buzzer, the
flash of a light, a touch on the dog's harness, and the use of different pitches
of a whistle in which the dogs had to differentiate between to determine which
pitch resulted in access to food.
Pavlov's experimental research gained much respect throughout Russia as well as
America and the rest of the nations. Although he began his investigations late
in life he managed to develop the major constructs of a fully realized field of
learning. He summarized his discoveries in his remarkable book, Conditioned
Reflexes.
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.
http://muskingum.edu/~psych/psycweb/history/pavlov.htm