Alan Lloyd Hodgkin (1914-1998), British physiologist. Hodgkin is known for discovering the potential difference between the core of a nerve axon and its membrane sheath, and that the potential is reversed as an impulse passes along the nerve. He developed a detailed theory of the origin of this potential difference in terms of sodium and potassium ion distribution. In 1963, Hodgkin shared the Nobel Prize in Physiology or Medicine with Andrew Huxley and Sir John Eccles. Photographed on 17th October 1963.