Hess, Walter Richard Rudolf (1881-1973), a Swiss physiologist, won the 1949 Nobel Prize in physiology or medicine for discovering how certain parts of the brain control organs of the body. Hess shared the Nobel Prize with Portuguese physiologist Antonio Caetano de Abreu Freire Egas Moniz, who originated the prefrontal lobotomy.

Hess was born in Frauenfeld, Switzerland. In 1906, he received a medical degree from the University of Zurich. He established his own ophthalmology practice in 1908 but gave it up in 1912 to become a research assistant in physiology. In 1917, Hess was appointed professor of physiology and director of the Institute of Physiology at the University of Zurich, positions he held until his retirement in 1951.

In 1925, Hess began to study the brain and its connection with the nervous system. He was particularly interested in the diencephalon in the front of the brain, and in particular the region of the diencephalon called the hypothalamus. Animal experiments and clinical observations of patients with brain damage had indicated that the diencephalon acted as the control center of the autonomic nervous system. Hess found that the hypothalamus regulated such automatic bodily processes as breathing and digestion—processes carried on without conscious control by the brain—through the autonomic nervous system.

In his research, Hess performed experiments on cats under general anesthesia. He inserted a needle electrode into each cat's hypothalamus and sent a weak electrical current through the needle to stimulate the region. He then observed and recorded the body's reactions. After the animal's death, Hess made serial sections of the brain and examined them under a microscope to determine the exact location of the electrode. He thus was able to map the centers of the brain responsible for control of bodily responses such as fear and hunger.

Hess published his findings in several books. He died in Ascona, near Locarno, Switzerland. Georg von Hevesy (geh AWRG vawn HEH ueh shee), or de Hevesy, a Hungarian-born Swedish chemist, won the 1943 Nobel Prize in chemistry for using isotopes as indicators in the study of chemical processes. An isotope is any of two or more forms of a given chemical element, Hevesy also helped discover the element hafnium.