Ivan Petrovich Pavlov
(1849—1936) Russian physiologist
Russian physiologist, who became professor of physiology in St Petersburg in 1886. While working on the physiology of digestion he discovered that the mere sight of food stimulates the production of digestive juices. For this work he was awarded the 1904 Nobel Prize for physiology or medicine. Pavlov went on to demonstrate operant conditioning in dogs and other animals. See also learning (Feature).