Book excerpt: Scientific Session on the Physiological Teachings of Academician I.P. Pavlov was originally published in 1951. Ivan Pavlov (1849-1936) was a great Russian scientist and physiologist. The name of Ivan Petrovich Pavlov is dear to all in the Soviet Union. It has become a symbol for unbounded patriotism and passionate service to Soviet science, a symbol of the struggle for the prestige of Soviet science and victory in the sphere of world scientific competition. As a man he combined gentleness and kindness with short-tempered irascibility and tremendous zeal for the work he loved. The greatness of Pavlov as a scholar is undisputed the world over. World fame came to him because he introduced his own original synthesis into every branch of physiology in which he worked. Almost every one of his experiments bore the character of an innovation, the stamp of a revolutionary spirit. He never forgot that his scientific achievement was achievement of Russian thought. It will be remembered that Pavlov did a great deal towards applying his achievements in the realm of physiology to practical medicine. His idea of "prolonged sleep" for the treatment of schizophrenia and other nervous and psychic disturbances was very widely used. Pavlov based his theories on the fact that during sleep the brain cells are in a state which protects them from further injury.