History of the department of Physiology

acad. Ivan Pavlov
(head 1981-1936)

 "The Ivan Pavlov Department of Physiology: A Scientific History"

Victor M. Klimenko, Juri P. Golikov

The brain organization unveiling and understanding of its activity is the boldest challenge to human intellectual powers, as the brain is the most complicated and thus the highest structure created by the nature. Since ancient time, the challenge was taken up by many outstanding people of different nations who belonged to different epochs. But no final answers were found as the problem itself was too multiple and the means for it exploration were limited. Although the world of science was accumulating more and more knowledge about the brain, especially in XIX century, activity of the higher compartments of cortex, psychic activity first of all, was still out reach of natural science. Russian physiologist Setchenov was one of the first who indicated the way towards the solution in his work “Brain reflexes”. He was followed by Pavlov and his colleagues who studied the same problem in the Department of Physiology of the Imperial Institute for Experimental Medicine in St. Petersburg (IIEM).

In 1890 in St. Petersburg the official opening of the Imperial Institute of Experimental Medicine, organized on Prince A.P. Oldenburgsky’s initiative took place. It was the first Russian scientific research institution in the field of biology and medicine. I.P. Pavlov was drawn into the elaboration of the new Institute’s activity trends, which included Departments of Chemistry, General Bacteriology, Pathologic Anatomy, Epizootology, and Syphilidology. I.P. Pavlov was invited to head the Department of Physiology and guide there researches –the task he successfully performed for 45 years: from 1890 till 1936.
At the same time (in April, 1890) I.P. Pavlov has got a position of the Head of Pharmacology Department at the Military Medical Academy, which he left in 1895, when he became the Head of the Physiology Department of the Academy. Since the Department did not have premises sufficient for his studies, students of the Academy practiced at the Department of Physiology headed by I.P. Pavlov at the Institute of Experimental Medicine. By the moment the Department has got a new building, specially arranged for scientific research work. Molding of researches from young students took place here with the active participation of I.P. Pavlov. Actually Pavlov’s physiological school was formed at the Department of Physiology of Institute for Experimental Medicine.
With the aid of chronic fistulae technique the Department studied the activity of gastro-intestinal tract, determined the mechanisms of digestive glands activity, elucidated role of the nervous system in regulation of this activity. The classical operation of oesophagotomy, isolation of a gastric pouch, pancreatic and bile fistulae and a number of other experimental techniques were evolved.
The innervation of gastric glands and physiology of pancreas were investigated here. At the Institute in spring of 1895 I.P. Pavlov delivered lectures on digestion. In the presentation he reviewed the achievements of the Department in this area of Physiology.
Those lectures were an important step in systematisation of vast information on nervous regulation of the digestive glands activities, on the laws ruling the production of digestive juices, on interaction of the stomach secretion with liver, pancreas, small intestines functioning, as well as with the functioning of other parts of digestive tract.

Pavlov demonstrated that wide use of experimental surgery in chronic experiments on animals gave an opportunity of investigating interactions of the digestive glands activities and mechanisms of their functioning. It was a new line of studies in digestion: exploration of physiological mechanisms of digestive glands activities under conditions of chronic experiment on a healthy animal with integral and continuously working digestion system. All his achievements in this field Pavlov summarized in his book “Lectures on the Work of the Chief Digestive Glands” (1897). In this book he added the eighth lecture to delivered previously seven ones – “Physiological data, human instinct and medical empiricism”. A year later the book was published in German being translated by his pupil A. Valter.
By 1904 when Pavlov was awarded with the Nobel Prize he had been engaged in scientific and pedagogical activities for 25 years. His studies made a large impact on the scientific community – never had physiology helped clinic medicine so significantly. In his lectures Pavlov regarded the process of digestion as a physiological conveyer which combined separate organs of digestive tract into a system. Such approach helped to create complete picture of digestion.
At every stage of his activity I.P. Pavlov paid great attention to the connection of physiological investigation and clinical medicine. Elaborating problems of physiology of digestion, he systematically studied questions of pathology of digestive organs too. In 1898-1904 researches of the digestive function of the liver, transport of food from the stomach to intestines were carried out under I.P. Pavlov’s direction. The general co-ordination of all parts functioning of the digestive tract was revealed as well. Special researches were devoted to bile, pancreatic, and gastric juice secretion into stomach. Conditions for such secretion and its significance for digestion were determined.
I. P. Pavlov’s research formed the background for a modern concept of disturbances in functions of gastro-intestinal tract and facilitated the development of adequate therapeutic methods for their treatment.

The highest appreciation of this period of I.P. Pavlov’s activity was in the laconic text of the Nobel Prize Diploma which was first given to a Russian scientist in 1904 “as a token of acknowledgement of his works on physiology of digestion, which reformed and widened the knowledge in this field”.
Pavlov’s works on physiology of digestion were a separate (completed) set of systemic studies, which was internationally acknowledged in 1904. At the same time they served as a starting point for large series of studies, which laid a foundation for a new area of physiology – physiology of higher nervous activity, or the theory of conditioned reflexes.
The phenomena of “psychic secretion” of digestive glands attracted Pavlov’s closest attention. Being an inborn experimenter Pavlov endeavored to fill in this “white spot” on the map of knowledge and decided to explore the psychic aspect of digestive glands activity. The decision was followed by 35 years of tenacious work devoted to exploration of special brain reflexes which Pavlov called “conditioned”. The history of science witnesses that conditional reflexes brought him more success, popularity and fame than his work on physiology of digestion awarded with Nobel Prize.
It is necessary to remark that it was F. Bidder and K. Schmidt from Derpt University, who for the first time in 1852 described gastric secretion from the gastric fistula conditioned by food demonstration. However, at that time the fact of psychic secretion of gastric juice did not attract serious attention of scientists. The data gained in the laboratory of physiology of Military Medical Academy by von Anrep went unnoticed, too, though he was one of the first who, before Pavlov’s work, came up to understanding the role of the nervous system in the gastric secretion. Finally, the problem was solved by Pavlov and Shumova-Simanovskaia and results were published in the article “Gastric gland innervation in dogs”.
The study carried out by Glinsky who was temporary adjoined to the Department of Physiology of IIEM played a crucial role in exploration of saliva glands nervous regulation and a basic role in physiology of conditioned reflexes. He was the first to invent the operation of implanting fistula into the duct of saliva gland in 1895, and he also performed the first experiments with reflective salivation in dogs. His work was not published by unknown reasons, but on May, 13, 1895 Pavlov presented the results at the meeting of the Society of Russian Physicians. For the second time Pavlov wrote about it in the article “The Technique, which Doctor Glinsky was the First to Apply” (1902). Fistula of saliva gland “after Glinsky” was accepted all over the scientific world as a most convenient method of precise and full registration of secreted saliva in chronic experiment.

Early in the 20th century Pavlov’s investigations attracted considerable interest of specialists. In his letter to Prince Oldenburg, curator of the Institute, Pavlov remarked that the Department of Physiology had become significant attraction for brilliant and loyal scientists not only from Russia, but from other counties, too. In 1902 doctors F.A. Stensma (Amsterdam), W. Straub and H. Fridental (Berlin University), W. Gross and Prof. O. Konheim (Heidelberg University), Prof. A. Chermak (University of Halle) worked in the Department under direction of Pavlov. Both translation of Pavlov’s ”Lectures on the activities of the main digestive glands” into German in 1898 and his lecture delivered at XIII International Congress of Physicians in July, 1900, where he for the first time addressed the international audience, were the reasons for the growing interest to his work. In his report “Experimental therapy as a new and fruitful technique of physiological studies” he did not limit himself by the contents of his latest works. He concentrated on the problems of “experimental therapy” and announced that “physiology with its special resources and its chances of success, being moved by its own initiative and for its own purpose, is aimed at such scientific work which, in its main idea, completely coincide with modus operandi of the medicine in its treatment of sick human beings”.

One of the obstacles on the way of natural science to understanding the activity of the higher compartments of the brain was the initial problem of the balance between physical and psychic processes in the nature, that is (in philosophical approach) the problem of material and spiritual, or the problem of objective and subjective. The whole history of science provides evidence of importance of this problem.
The theory of psychic excitation of saliva glands was elaborated in 1896 – 1901 by Pavlov in co-operation with Wolfson and Snarsky. In Wolfson’s dissertation “Activity of saliva glands” (1898), which was performed at the Department of Physiology, psyche was regarded as a special substance regulating the process of salivation.
In the dissertation accomplished by Snarsky “Analysis of normal conditions for the dog’s saliva glands functioning” (1901)(which was also carried out at the Department of Physiology), the facts were explained from the point of view of zoo-psychologist. Discussing the mechanism of “psychic” salivation the author, for example, compared animals and human beings with their subjective inner world. That approach was not accepted by Pavlov. Two scientists separated as their views were incompatible. Dr. Snarsky persisted in looking for explanations of the phenomena in the field of subjective. Pavlov, by his own words, “was astonished by scientific unfruitfulness of such approach to the problem”, and he began to look for another way out of the difficult situation presented by it. After many hours of speculations and “hard intellectual struggle” he decided to treat psychic excitation as a “pure” physiologist, that is - as an objective external observer and experimenter who deals exclusively with external phenomena and their interactions. This decision was made in 1901.

Pavlov was sure that physiological approach to psychic phenomena exploration would allow to develop fruitfully the part of the brain physiology which was to explore the role of the brain in organizing the interactions between the organism and its environment.
The moment of Pavlov’s statement of his “physiological” approach to the phenomenon of “psychic salivation” is regarded as the birth date of a new notion “conditioned reflex”.
The first work on conditioned reflexes - “Materials on physiology and psychology of saliva glands” was carried out on Pavlov’s suggestion by Tolotchinov who was temporary adjoined to the Department of Physiology. The results were presented in 1902 at the Congress of Physicians and Natural Scientists of Northern Countries of Europe in Helsingforse (Finland). Tolotchinov described some external conditions under which temporary connections appear in the cortex. He also established the fact of the natural reflex generating, the facts of its dissipation and restoration, and the possibility of external inhibition of a newly elaborated reflex. The experiments registered not only secretarial, but also a motor conditioned reaction.
Pavlov, as many scientists looking for the explanation of the essence of life, was interested in the way by which the brain generated mind, mentality. All his life since his youth he longed to fathom the depth of the human psyche. In the first report on the theory of conditioned reflexes, delivered in Madrid at XIV International Medical Congress in 1903 he said: “Relying on the likeliness and sameness of external phenomena all objective data obtained in experiments will be used by future science to explain our subjective world. Thus our mysterious nature will be illuminated, and the mechanism of the most interesting human function – of his mind, torments of his mind – will become clear”.
The way of deep and manifold exploration of conditioned reflexes chosen by Pavlov in 1901 provided natural science with the opportunity to regain its unconstrained development and enabled it with the power to tread into the “last facet of life” - into mechanisms of the brain higher compartment activities.

The theory of conditioned reflexes germinated in the Department of Physiology of the IIEM pre-ordained the field of future scientific activities for Pavlov, his apprentices and colleagues.
The formation and development of I.P. Pavlov’s works on physiology of higher nervous activity were permanently linked with the Physiological Department of the Institute of Experimental Medicine. Here I.P. Pavlov and his disciples carried out researches which permitted Pavlov to give the first lecture on the theory of conditioned reflexes at Medical Congress in Madrid in April 1903. In the lecture “Animal Experimental Psychology and Psychopathology” he demonstrated an objective method of study of higher nervous activity in animals and in human. “Only by the way of objective investigations,” 1.P. Pavlov stated, “step by step we will reach the complete analysis of that infinite device as a whole, which forms the life on the Earth”.
The Congress lasted from March, 30 till April, 26 and there were 6.961 delegates who participated in its work. The Russian delegation consisted of 297 members. Pavlov and his wife were well acquainted with many European capitals, but in Madrid they were deeply impressed by exposition of Francisco Goya works in Prado. They spent much time standing in front of the pictures. Pavlov and his wife also visited Escorial and Toledo.

Beginning from 1904 all efforts of the Department staff were focused on methodological aspects of the conditioned reflexes exploration. According to Pavlov “high speed of accurate facts accumulation and their easy interpretation presented a drastic contrast with uncertain and questionable results provided by the subjective approach”.
It was in 1905 that the method of “artificial” conditioned reflexes was introduced into practice of research. The technique allowed carrying out a quantitative analysis of the processes in higher nervous activity. As the result Pavlov formulated the main principle of the conditioned reflexes theory according to which the magnitude of the response depends on the intensity of the stimulus.
By 1906 almost all types of cortical inhibition had been discovered: conditioned, differentiating, retarding, external and sequential. Basics of the conditioned reflex generalization were laid, and conditioned trace reflexes were discovered. Under Pavlov’s guidance investigations were carried out using extirpation of different areas of cerebral cortex (in dogs) to reveal the link between conditioned salivary reflexes and cerebral cortex.
The most important results Pavlov presented in his lecture devoted to T. Huxley, which he delivered in London in 1906. At the conclusion of his presentation he felt it necessary to stress his strong belief of the inevitable unity between physiology and medicine. “If the doctor in reality and even more so in ideal is a mechanic repairing a human organism, - Pavlov remarked - then any new physiological achievement will sooner or later inevitably expand his power over the mechanism, the power to maintain and repair it.”

Celebratory meeting of Russian Physicians Society devoted to the memory of I.M. Setchenov, which took place on March, 22, 1907, was opened with the speech delivered by Pavlov. He stated a high value of Setchenov’s studies in the field of physiology in general and especially in the area of physiology of the nervous system. He also informed the audience that celebratory meetings commemorating Setchenov would become an annual event.
In 1907 Pavlov’s disciple N.I. Krasnogorsky working with children obtained the data on role of conditioned reflexes in forming of behavior. In 1908 other person, P.M. Nikiforovskiy, made first steps towards application of the conditioned reflexes technique to pharmacology.
Beginning from 1908 investigations in the field of physiology of higher nervous activity under I.P. Pavlov’s direction were conducted not only at the Physiological Department of the Institute of Experimental Medicine and the Department of Physiology at the Military Medical Academy but in the Physiological laboratory of the Academy of Sciences. However the Physiological Department remained the main centre of scientific work and the experimental base for the development of studies of Pavlov physiological school. From 1891 to 1917 more than 110 persons, mostly the attached ones and practicians, worked here during different periods of time under the direction of I.P. Pavlov.

Dissertations and studies at the Department were accomplished by B.P. Babkin, G.P. Zelioniy, V.V. Savich, L.A. Orbeli, N.I. Krasnogorsky, I.V. Zavadsky, G.V. Folbort, I.S. Tsitovitch, A.N. Krestovnikov, P.S. Kupalov, V.S. Deriabin, N.A. Rozhansky and many others.
In connection with the development of researches in physiology of higher nervous activity, a problem of establishing of a special laboratory equipped with soundproof chambers arose. Since the Institute did not have sufficient means I.P. Pavlov turned to Ledentsov Fund for them. In 1910 in Moscow at the Society Council Session he gave a lecture about tasks and arrangement of a modem laboratory for studying higher part of the central nervous system in higher animals. The Society granted 50,000 rubles to I.P. Pavlov and in 1913 the “Tower of Silence”, a three-storied building with three sound proof chambers, was built up. Further five chambers were equipped after 1917.
In 1911 Pavlov started a broad investigation of cortex inhibition, formulated the major laws of neural processes development in the brain cortex and also defined the notion of two main mechanisms operating in the central nervous system: the mechanism of temporary connection and the mechanism of analyzer. Further on during his scientific activities he returned to these definitions repeatedly.

In 10 years after the first presentation on conditioned reflexes Pavlov delivered a report “Investigation of HNA” at the final meeting of the IX International Physiological Congress in Groningen (Holland). Such outstanding physiologists as Ch. Sherrington, E. Starling, G. Gemmeter, E. Fisher participated in the work of the Congress. In his report Pavlov substantiated his idea that analysers were special apparatus of the nervous system, and he also presented the perspective of investigation in this direction, based on the idea of unity of the centre and periphery. He also mentioned the possibility of conditioned reflexes being hereditary – the idea, which later transformed into the problem of high cerebral functions inheritance.
During World War I, during two revolutions that followed it and during the Civil War scientific work went on in the Institute. Period of 1918 – 1920 was especially difficult: the country was in ruins, as the result of starvation and cold it was impossible to experiment on dogs.
In 1921 – 1923 scientific work in the Department of Physiology gradually came to normal, investigations were renewed. In his report “Normal activity and general constitution of cerebral cortex” delivered in 1922 at the meeting of the Society of Finnish Physicians in Helsingfors Pavlov distinguished 6 types of events which “embraced the whole HNA without residue”. In those 6 types he included the excitation, inhibition, movement (irradiation and concentration), mutual induction, connecting and disconnecting, and, finally, analysis. It was a report which summarized the most important results of his two-decade work. In 1923 Pavlov’s book “Twenty Years Experience in Objective Study of Higher Nervous Activity (Behaviour) of Animals” was published. It comprised his articles, reports, lectures and speeches presented in chronological order, so that it reflected the course of development of the theory of conditioned reflexes. Emphasising special significance of the sixth edition (the last one published during his lifetime) of the “Twenty Years Experience” Pavlov wrote in January of 1936 that the book was enriched “abundantly” – 12 new works were added to it. According to Pavlov those works clearly demonstrated “how immensely the horizon of research has extended… Physiology, pathology with therapy of cortex of the brain and psychology with its practical applications start to join, to merge, so that they become the same field of scientific work, and, judging by the results, to their mutual benefit.”

In 1925 – 1927 much attention was paid to investigation of nervous system types, to studying different kinds of internal inhibition and their mutual induction. In 1927 Pavlov’s book “Lectures on the Work of Large Hemispheres of the Brain” was published. In the same year he suggested that nervous system types would be studied on dogs, and while researching other problems the type should be taken into consideration.
1922-1935 was time of active development of the Physiological Department and deep study of problems of physiology and pathology of higher nervous activity under the supervision of I.P. Pavlov. In 1923 I.P. Pavlov got a territory for establishing a special nursery for breeding and keeping experimental animals in the country, in the vicinity of village Koltushi near St. Petersburg. But a short time later I.P. Pavlov decided to organize here a Biological station for experimental investigations. The station was officially opened in 1926, it became a base for investigation of conditioned reflexes in dogs in connection with in-born peculiarities of their nervous system. The stone-work laboratory building was completed in 1933. In the same year the first studies of higher nervous activity of anthropoid apes were carried out at the Biological station under the direction of I.P. Pavlov.
Koltushi acquired the world renown as the “Capital of Conditioned Reflexes” at the XV-th International Physiological Congress which took place in Leningrad and Moscow in 1935. Several days before the Congress started a monument to the Dog was established by initiative of I.P. Pavlov not far from the building of the Physiological Department on the territory of the IEM. The statue was created by the sculptor Bespalov.

American physiologist, Harvard University Professor Walter B. Cannon (1871-1945) wrote in memoirs about his meetings with I.P. Pavlov: “Last time I saw Pavlov in Leningrad and Moscow at the conferences of the Physiological Congress in 1935. He was 86 years old then but he looked lively, full of his former energy. I will never forget the day we spent together in the environments of Leningrad, in the huge new buildings of the Institute built by the Soviet Government for Pavlov’s experimental works. During our talk Pavlov heaved a sigh and said regretfully that he did not have such huge possibilities 20 years before”.
In 1918 I.P. Pavlov resumed his visits to a mental hospital with the aim to study physiological mechanisms of cerebral hemisphere cortex activity of man. In those years Pavlov paid more attention to studies in psychiatric hospital, which he started in the middle of 1890th with the aim to explore physiological mechanisms of human cerebral cortex activity. In 1923 he decided to investigate natural psychopathologic syndromes and psychic diseases. In 1931 on I.P. Pavlov’s initiative, two clinics were established: a nervous one (on the basis of neuropsychiatry dispensary) and a psychiatric one (on the basis of mental hospital) at the Institute, actually at the Physiological Department. Neurasthenia, hysteria and psychasthenia, narcolepsy, schizophrenia, circular psychosis were investigated •in the clinics. The types of higher nervous activity of patients with different sickness dynamics in the cases of neuroses and psychoses were studied. The searches for pathogenetic methods of therapy were conducted as well.
Remarked it should be that investigations on physiology and pathology of higher nervous activity reached their peak in 1930s. Positive and negative induction phenomena, their temporal and spatial features, were discovered with the conditioned reflex method. A concept of sleep as well as sleeping control methods were elaborated there. A possibility of producing conditioned reflexes to complexes of irritants working concurrent or one after another, as well as producing reflexes to time intervals (“time reflex”) was discovered.

The researches on conditioned reflex activity in the cases of disturbances of normal work of higher parts of brain, elucidation of conditions inducing such disturbances led I.P. Pavlov to the elaboration of the concept of four main types of the nervous system, which later formed one of the most important part of physiology of higher nervous activity. Basing on the results of the investigation of behavior of anthropoids I.P. Pavlov proposed a concept of conditioned sensory and signal temporal associations. The latter meant the possibility of forming genetic causative relations between subjects and events in anthropoids. I.P. Pavlov stated his belief that it is incorrect to interpret the behavior of highly developed animals relying on the mechanism of conditioned reflex only.
The formation and development of Pavlov scientific school in 1903-1925 (when he left formally his work at the Department of Physiology at the Military-Medical Academy) was characterized by concentration of attention of the chief and his disciples, for the most part, on questions related to the working on problems of physiology of higher nervous activity. Under the guidance by I. P. Pavlov and with his personal participation the mechanisms of conditioning and closing function of the brain were studied. The research enabled to state the idea of the analyzing and synthesizing activities of the higher brain levels. The role of conditioned stimuli strength was formulated, the main nervous processes (the excitation and the inhibition) were characterized, the phenomenon of beyond-limits-inhibition and mutual induction was discovered, the theories of the dynamic stereotyping, experimental neuroses, and types of higher nervous activity were evolved, and the theory of sleep and hypnosis was advanced.

The problems of experimental pathology of the higher nervous activity were worked upon at the Dept., and pharmacological substances restoring this activity were studied. Results of the work performed at nervous and mental clinics enabled to provide physiological basis of mechanisms of a number of nervous and mental diseases in human.
Under I.P. Pavlov’s guidance P. K. Anokhin, D. A. Biriukov, K. M. Bykov, A.G. Ivanov-Smolensky, F.P. Maiorov, L.A. Orbeli, I.P. Razenkov, A.D. Speransky worked at the Dept., as well as many other scientists -disciples of the Pavlov physiological school.
It was the period when many prominent scientists, representatives of I.P. Pavlov’s school left the Department of Physiology of the Institute of Experimental Medicine and began to work independently. Among them there were scientists who influenced the development of physiology abroad, e.g. von G.V. Anrep. He worked after 1920 at London and Cambridge Universities, became a Member of Royal Society and for more than 20 years headed the Department of Physiology at the Egyptian University of Cairo. B.P. Babkin, who introduced I.P. Pavlov’s ideas into physiological researches in England and Canada, was a Member of Canadian Royal Society. V.N. Boldyreff emigrated to Japan in 1918 and in 1922 moved to the USA, where till 1940 he headed the Pavlov laboratory at the sanatorium in the State of Michigan. E. Konorsky developed neurophysiology in Poland, and Ten-Kate who worked in Holland. William Horsley Gantt, who worked at Pavlov’s laboratories in 1925-1929, played a great role in the subsequent development of I.P. Pavlov’s ideas in the USA. In archive of Horsley Gantt there is a rich collection of documents connected with I.P. Pavlov. Among other things he organized Pavlov Scientific Society in the USA.
Besides the wide field of investigations in physiology and pathology of higher nervous activity I.P. Pavlov contributed to the development of new trends of research at the Physiological Department. It was physiology and pathology of cortical-visceral relations, first and foremost, a trend originated at the intersection of physiology of higher nervous activity and physiology of vegetative functions. Investigations in this field began with the work “Development of Urinary Excretion Conditioned Reflexes” carried out in 1926 by I.P. Pavlov’s disciple K.M. Bykov in collaboration with I.A. Alekseev-Berkman.

By 1931 significant experimental material on cortical regulation of activity of internal organs had been accumulated.
The second trend of research carried out on I.P. Pavlov’s initiative, was the first in Russia systematic study of the influence of different health resort factors on animal and human organisms. In 1931 the further development of these two trends was passed on to the Department of Applied Physiology newly organized at the Institute (from 1931 — the Department of Common Physiology), with K.M. Bykov as the head (now - K.M. Bykov Department of Visceral Systems).
In 1933 one of the oldest disciples and collaborators of I.P. Pavlov L.A. Orbeli organized the third physiological department in the Institute - the Department of Special and Evolutionary Physiology. Systematic study of some branches of physiology, which had not been studied yet in the Soviet Union, as well as the problems of evolution of functions of animal and human organisms were the subjects of this Department. It is interesting to remark that L.A. Orbeli became successor of I.P. Pavlov on the position of Physiology Department’s Head of MMA, when Pavlov left it in 1925.
So, by the end of I.P. Pavlov’s life, at the Institute of Experimental Medicine, two physiological departments headed by Pavlov’s disciples had been established besides the Physiological Department and the Biological Station. Both were oriented to the study of physiology and pathology of higher nervous activity. To that time I.P. Pavlov was a Honorary Member of more than 100 Scientific Societies many countries of the World, including Cambridge University.
Pavlov died on 27.02.1936. Last time he visited the Department of Physiology of IEM on February, 18, what is certified by the sheet of a desk calendar on his desk in the study which is the memorial now. Coffin with the body of Honorary Director of the Institute for Experimental Medicine, Nobel Laureate, was placed for the last farewell in Tavritchesky Palace, former sitting place of Duma – Russian Parliament before Revolution. He was buried in Academician yard of memorial cemetery “Literary brow”.

By the decision of the Government his name was given to the Department of physiology of IEM founded by him, to 1-st Leningrad medical Institute (nowadays the St.-Petersburg State Medical University named after. I.P. Pavlov), to Physiological Institute of the USSR AS (nowadays Institute of Physiology named after I.P. Pavlov of the Russian Academy of Sci), and also to many other research and educational medical institutions.
To perpetuate the memory of the organizer and the first Head I.P. Pavlov’s office was preserved as a memorial in the Department of Physiology, and I.P. Pavlov’s museum was opened in his apartment on Vassilievsky Island, which is a part of St. Petersburg.
After death of I.P. Pavlov the Dept. was headed by Academicians the USSR Acad. Med. Sci. L.A. Orbeli (1936 to 1937), then by P.S. Kupalov (1937 to 1964), M.M. Khananashvili (1965 to 1976) and G.A. Vartanian (1976 to 1995). Since 1995 I have been carrying this honorable burden on my shoulders.
Academician of the USSR Acad. Med. Sci. P.S. Kupalov was the nearest disciple and colleague of I. P. Pavlov, about whom Pavlov sad “Kupalov is my alter ego”. Under the guidance of P.S. Kupalov new regularities were revealed in brain functions: shortened conditioned reflexes were discovered, the mechanisms of the tonus regulation were found in the brain cortex, properties of long-term neural processes were studied under normal and pathological conditions, properties of cortical representation of the unconditioned reflexes were characterized. Owing to the technique of situational conditioning suggested by P. S. Kupalov, general regularities of the animal higher nervous activity were studied under conditions of unrestrained behavior and some new causes for experimental neuroses and their mechanism were revealed.
Simultaneously with P.S. Kupalov, another disciple of I.P. Pavlov Correspond. Member of the USSR Acad. Med. Sci. K.S. Abuladze carried out his investigations. He is the author of original technique based on outward extension of tongue’s symmetrical areas which was used to study the conditions of joint and separate functioning of the brain hemispheres, and of unilateral conditioned reflexes.
The experiments carried out under the guidance of Academician of the USSR Acad. Med. Sci. M. M. Khananashvili resulted in establishing certain ideas of the integrated systems of conditioned ref lexes as the functional units of general behavior, as well as of the informational neuroses in animals and in humans and of the ways of their prophylaxis and treatment. Influence of various forms of animal interspecies communication upon the mechanisms of higher nervous activity was studied under normal and pathological conditions.

In 1976 Khananashvili left Department for the position of Director of Beritoshvily Institute of Physiology in Tbilisi, capital of Georgia. During two years the investigations in the Department were continued under guidance of Professor Silakov. Scientists used microelectrode technique to reveal the closing of temporal connection. Last occurs due to activity of a special group of unspecific neurons called “the learning neurons”. Their particular feature involves the ability to establish new functional connections among themselves in the course of conditioning. A concept of microsystems of such learning neurons as the structural-functional basis of the closing has been advanced.
Later, when the Department was headed by Correspond. Member of the USSR Acad. Med. Sci. G.A. Vartanian attention was focused on the problem of reinforcement and of the role of emotional mechanisms and of unconditioned reflexes mechanisms in the brain reinforcement function. New details were revealed concerning the role of environmental agents in neurophysiological and psychophysiological mechanisms of emotional behavior. A number of main structural and functional patterns of the brain emotional mechanisms were described for animals bred under the conditions of communicative deprivation.

Ivan Pavlov page

Tower of Silence

Monument to a Dog