Leo Hurvich passed away on April 25, 2009. The following obituary appeared in the May 5, 2009 edition of the University of Pennsylvania Almanac (http://www.upenn.edu/almanac/volumes/v55/n32/obit.html#2).
Many people do not know that Leo Hurvich proposed correctly that the brain was using opponent process as a general model of how the brain works. Opponent Process as a Model of Neural Organization by Hurvich & Jameson February 1974 American Psychologist ******* Dr. Leo M. Hurvich, professor emeritus of psychology, died at home in New York City April 25, at age 98. Working closely and effectively as a team and co-publishing since 1945 (and marrying in 1948), Dr. Hurvich and his wife Dorothea Jameson, who predeceased him in 1998, received joint recognition for their major contributions to our understanding of how we perceive color and of how our visual systems operate. Thus, they were elected to the major honorific societies including the National Academy of Sciences and the American Academy of Arts and Sciences, received many awards, and published numerous joint as well as individual articles and books. Dr. Hurvich earned his undergraduate and graduate degrees from Harvard University. After receiving his PhD from Harvard’s psychology department in 1936, he worked there until 1947, then at the Color Technology Division of Eastman Kodak. In 1957, he returned to academia, first in the psychology department of New York University (until 1962) and then at the University of Pennsylvania (until retiring as professor emeritus in 1979). He also spent a year as a visiting research professor at Columbia University (1971) and a year at the Center for Advanced Study in the Behavioral Sciences (1981). When Dr. Hurvich and Professor Jameson began investigating the nature of color vision at Eastman Kodak, the dominant theoretical idea was the Young-Helmholtz trichromatic theory, which states the wavelength composition of light is encoded by three separate classes of cone photoreceptors. The essential features of this trichromatic theory were well-worked out by the mid-19th century, and it successfully explained how mixtures of primary colors can mimic the appearance of arbitrary lights and provided the basis for color reproduction technologies. Dr. Hurvich and Professor Jameson found, however, that trichromatic theory did not provide a good account of the way that colors appear, and they revived and modernized what had until then been seen as an alternative proposal, namely that color processing relies on three opponent visual channels each of which signals mutually exclusive perceptual response states (red versus green, blue versus yellow, and white versus black for the three channels respectively). They devised an ingenious hue cancellation procedure which allowed experimental quantification of the properties of the opponent channels and in a series of papers that are remarkable for their rigor and scope, they developed an opponent-process model that provides a unified account of normal human color vision and of deficits in color vision that had previously gone unexplained. An important feature of their work was that it explicitly coupled the opponent-color channels to the cone photoreceptors of trichromatic theory, thus clarifying the complementary nature of what had previously been viewed as competing ideas. Their behavioral work was synergistically supported by the discovery of color-opponent cells in fish (by G. Svaetichin) and subsequently in monkeys (by R. DeValois). The theoretical framework they developed was highly influential in guiding a generation of subsequent research aimed at elaborating and refining the characterization of opponent-color processes inferred from behavioral measurements, and at identifying the neural substrates for these processes. “Although he retired in 1979, Dr. Hurvich remained active in writing and conference participation until about the turn of this century. His 1981 book, Color Vision, provides a comprehensive treatment of the field that is still in wide use, and the impact of his and Professor Jameson’s contributions will remain with us for much longer,” said his friend, Dr. Julian Hochberg. Dr. Hurvich is survived by many friends and the children for whom he and his wife had been appointed guardians. Memorial donations may be made to the Center for Constitutional Rights, 666 Broadway 7th floor, New York, NY 10012. --- To make changes to your subscription contact: Bill Southerly ([email protected])
