 Ivan
Petrovich Pavlov was born on September 14, 1849 in the village of
Ryazan, Russia, the son of Peter Dmitrievich Pavlov, who was the
village priest. Like most other children from Ryazan, he went to the
Church school, and was later was enrolled in a theological seminary.
It was after reading The Origin of the Species by Charles
Darwin, and the works of Russian physiologist I. M. Sechenov that
Pavlov decided to abandon his theological studies and become a man of
science. He left the seminary in favor of the University of
St-Petersburg, where he enrolled in the Natural Sciences program.
Pavlov realized his favorite subject was that of physiology, and
it wasn't long before he that he produced, in tandem with a fellow
student, his first paper, a work on The Physiology of the
Pancreatic Nerves for which he was awarded a gold medal.
Pavlov completed his course and received the degree of Candidate of
Natural Sciences, but not one to rest on his laurels, he went on to
study at the Academy of Medical Surgery where he was awarded
another gold medal and later on, a fellowship; in addition to this,
Pavlov was also Director of the Physiological Laboratory at the clinic
of S. P. Botkin , a famed Russian physician. It was there he
produced his doctoral thesis on The Centrifugal
Nerves of the Heart, for which he was later awarded the Nobel
Prize in Medicine/ physiology (1904).
1890 was an important year for Pavlov, as he was asked to oversee the
organization and run the Department of Physiology at the Institute of
Experimental Medicine. It was there he would conduct his most
historically significant research, and also where he would remain for
the rest of his life. That same year, Pavlov was also appointed
Professor of Pharmacology at the Military Medical Academy.
Pavlov's main area of research throughout his scientific career was
on the digestive process, which brought on a series of experiments
exploring the correlation between the nervous system and the
autonomic functions of the body. Pavlov experimented with dogs, studying the relationship between salivation and digestion.
By
applying stimuli to the animals in a variety of ways, using sound,
visual, and tactile stimulation, he was able to make the animals
salivate whether they were in the presence of food or not; a
phenomenon he called the conditioned reflex.
Pavlov was also elected a corresponding member of the Russian Academy
of Sciences in 1901, the Nobel prize in 1904, he was elected
Academician of the Russian Academy of Sciences in 1907, given an
honorary doctorate at Cambridge University in 1912, and awarded the
Order of the Legion of Honour in 1915, the recommendation of the
Medical Academy of Paris.
Dr. Ivan Pavlov died in Leningrad on February 27,1936.
In addition to the many honors he received during his career, Pavlov
should also be credited for the extraordinary impact his work, and
that of his students and followers has had in the field of physiology.
| Conditioned vs. Innate Reflex
An innate reflex is an instinctive and unlearned reaction to a
stimulus. Although we do not know the exact cause of it, yawning is an
innate reflex, as it is seen in newborn infants as well as adults.
It is believed that yawning occurs as the result of a change in
physical state, from alertness to fatigue or as we awake from sleep.
Sneezing is another example of an innate reflex, as it is the
uncontrolled reaction to the introduction of foreign particles
in one's nose, or a rapid change in temperature. Attempts to
stifle a sneeze are often unsuccessful, as the involuntary reaction is
already underway.
A conditioned reflex is learned, either through negative or
positive stimuli. The fear of snakes is a learned reflex, as
young children who would play with snakes and other reptiles with
innocent fascination are soon taught to fear by example or stimuli
i.e., a mother screams and pulls her child away from a harmless garter
snake, reinforcing the gesture with a statement such as "You could
have been bitten!"
Pavlov's lectures on the science of conditioned reflexes, which are
available on this website.
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