David H. Hubel received the 1981 Nobel Prize in Medicine for his discoveries concerning information processing in the human visual system. His work shed light on one of the mind's darkest mysteries, the process by which the brain interprets the signals it receives from the eyes. Born and raised in Canada, he attended McGill University Medical School and completed his residency in neurology at Johns Hopkins University in Baltimore. He began his research in the visual cortex of the brain while serving in the U.S. Army at Walter Reed hospital, where he developed the microelectrode and...