Orbeli, Leon

(also Levon Abgarovich Orbeli). Born June 25 (July 7), 1882, in Yerevan; died Dec. 9, 1958, in Leningrad. Soviet physiologist. Academician of the Academy of Sciences of the USSR (1935; corresponding member, 1932), the Academy of Sciences of the Armenian SSR (1943), and the Academy of Medical Sciences of the USSR (1944). Honored Scientific Worker of the RSFSR (1934). Hero of Socialist Labor (1945). Colonel general in the medical service. Brother of I. A. Orbeli.

In 1904, Orbeli graduated from the Military Medical Academy in St. Petersburg. From 1907 to 1920 he worked at the Institute for Experimental Medicine. He was a student and very close associate of I. P. Pavlov. From 1918 to 1957, Orbeli headed the physiology laboratory of the P. F. Lesgaft Scientific Institute; from 1920 to 1931 he was a professor at the First Leningrad Medical Institute. From 1925 to 1950 he headed the subdepartment of physiology at the S. M. Kirov Military Medical Academy; from 1943 to 1950 he was director of the academy. Orbeli was director of the I. P. Pavlov Institute of Physiology of the Academy of Sciences of the USSR (1936–50) and of the I. P. Pavlov Institute of Evolutionary Physiology and Pathology of Higher Nervous Activity of the Academy of Medical Sciences of the USSR (1939–50). From 1939 to 1948 he was academician-secretary of the division of biological sciences of the Academy of Sciences of the USSR; he served as the academy’s vice-president from 1942 to 1946. In 1956, Orbeli founded and headed the I. M. Sechenov Institute of Evolutionary Physiology of the Academy of Sciences of the USSR.

Consistently applying the principles of Darwinism to the study of physiology, Orbeli developed a new scientific discipline —evolutionary physiology. He devoted particular attention to the application of the principles of evolution to the study of all the subsystems of the nervous systems in animals and man. In studying the sympathetic nervous system, he discovered its adaptotrophic function; this discovery contributed to the understanding of the role of the sympathetic nerves in the body. Orbeli introduced the concept of the function of the cerebellum, demonstrating that the cerebellum not only directs motor coordination but also regulates the autonomic functions of the body.

Orbeli made a great contribution to the study of pain and the physiology of analyzers. He conducted a detailed study of individual receptor systems and investigated the interaction of afferent, sensory, systems. In his research on the activity of the central nervous system, Orbeli made a close study of the influence of subcortical centers on the functional state of the cerebral cortex.

Orbeli promoted the study of human physiology, especially the problems of vital activity under unusual and extreme conditions. He organized and headed projects to improve deep-sea diving and took part in the study of a number of problems of aviation physiology and medicine. Orbeli founded the first Laboratory of Age Physiology in the USSR. Orbeli directed research on the physiology and pathology of higher nervous activity in humans.

Orbeli received the State Prize of the USSR in 1941, the I. P. Pavlov Prize of the Academy of Sciences of the USSR in 1937, and the I. I. Mechnikov Gold Medal of the Academy of Sciences of the USSR in 1946. He was a member of the Paris Biological Society (1930), the Leopoldine German Academy of Nature Lovers (1931), and other foreign societies and academies of science.

Orbeli received four Orders of Lenin, four other orders, and a number of medals.