The Nobel Prize in Physiology or Medicine 1967
Born: 18 November 1906, New York, NY, USA
Died: 12 April 1997, Cambridge, MA, USA
Affiliation at the time of the award: Harvard University, Cambridge, MA, USA
Prize motivation: "for their discoveries concerning the primary physiological and chemical visual processes in the eye."
Prize share: 1/3
Our vision functions because light from the surrounding world is captured by many light-sensitive cells in the retina at the back of the eye. George Wald found that vitamin A is an important component in rhodopsin, a light-sensitive substance in the retina, and explained in a series of studies from the 1930s to the 1960s how light causes rhodopsin to change form and be converted. This conversion gives rise to signals in a complicated network of nerve cells by which a number of reconnections and transformations occur before the signals eventually are transformed into visual impressions in the brain.