Ivan Pavlov. By: Valentina Villeda. Influences in Early Life.
Ivan Petrovich Pavlov was born on September 14, 1849 in the small town of Ryazan, about 100 miles southeast of Moscow. He was the eldest of five children. His father was a priest in one of the poorer parishes. Pavlov lived most of is early life in extreme poverty. Pavlov was going to study to become a priest but he then changed his mind. So he entered school during the Russian cultural revolution of the 1860's and was exposed to the leaders of this revolution, such as Turgeanyev, Doskovsky, Tolstoy, etc. However, he was apparently most heavily influenced by Pisarev, from whom he learned of Darwin's theory of natural selection and the famous Russian physiologist Sechenov, who had just published Reflexes of the Brain in 1863. It is clear that these kinds of influences on Pavlov steered him in the direction of science and consequently because he left the ecclesiastical seminary and entered the Mathematics-Physics Department at St. Petersburg State University.
In 1875 Pavlov graduated from the University with a degree in natural sciences. However, due to his interest in physicology he started work as an assistant in the Department of Physiology in the Medical Surgery Academy and in 1879 received a medical diploma. He was then recommended for an appointment with Andre Botkin, who was the most renowned clinician in St. Petersburg at the time. Botkin assigned Pavlov the task of heading his recently established experimental research laboratory. Since Botkin had little interest in experimental work, Pavlov was able to work pretty much independently on problems of his choice. He worked here until 1890. He was heavily influenced by Botkin's theories on the role that the nervous system plays in the regulation of physiological function, and it was here that Pavlov began his studies of the peripheral nerves of the heart and where in 1883 he successfully defended his doctoral dissertation in this area.
The traditional teaching of the "cephalic phase" of gastric and pancreatic secretion originated with Pavlov. Students learn that stimulation of gastric secretion of acid and pepsin and stimulation of pancreatic secretion of digestive enzymes starts with the anticipation of the ingestion of a desirable meal and is mediated by input to the stomach and pancreas from efferent nerves of the vagus. Pavlov’s cephalic phase was a brilliant demon-stration of a brain-gut interaction. The stimulation of secretion evoked by linking environmental stimuli with presentation of appetizing food was discovered by Pavlov in his dogs and was called by what is now a classic term: a "conditioned reflex."
The descriptions by the American army surgeon, William Beaumont of how the appearance of the gastric mucosa mirrored the emotional state of his patient Alexis St. Martin preceded Pavlov’s work on brain-gut interactions in dogs. Beaumont’s studies laid the groundwork for Pavlov’s work and are the beginning of the arrow of time that points to what modern physiologists now understand about the digestive tract as an integrated system.
Pavlov was a master experimental surgeon. His development of the "Pavlov pouch" enabled the discovery of the cephalic phase of secretion and its role in the anticipatory preparation of the upper digestive tract for the ingestion of a meal.
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 are formed. He dedicated much of the rest of his career further exploring this finding.