Roger Wolcott Sperry was an American neuropsychologist, neurobiologist, cognitive neuroscientist, who, together with David H. Hubel and Torsten Nils Wiesel, won the 1981 Nobel Prize in Medicine for his work with split-brain research. A Review of General Psychology survey, published in 2002, ranked Sperry as the 44th most cited psychologist of the 20th century. The Nobel Prize in Physiology or Medicine 1981, announced October 9, 1981. Roger W. Sperry (1/2), “for his discoveries concerning the functional specialization of the cerebral hemispheres”. David H. Hubel (1/4), “for their discoveries concerning information processing in the visual system”. Torsten N. Wiesel (1/4), “for their discoveries concerning information processing in the visual system”. Roger W. Sperry: born 1913, Hartford, CT, USA. David H. Hubel: born 1926, Windsor, ON, Canada. Torsten N. Wiesel: born 1924, Uppsala, Sweden. Wiki link Wiki link Wiki link Data: the Nobel Foundation (CC0).