Encyclopedia of Color Science and Technology

2016 Edition
| Editors: Ming Ronnier Luo

Rushton, William A. H.

  • Stephen Westland
Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-8071-7_345

William Albert Hugh Rushton was a British physiologist who made important contributions to our understanding of color vision and perception. He is perhaps best known now for his development of the principle of univariance.

Rushton was born in London on 8 December 1901. He entered Cambridge University as a medical student in 1921 and obtained a degree in physiology in 1925. He received a PhD degree in 1928 working under Prof. E.D. Adrian for his research investigating the flow of current in and around nerves to determine the portion of the current responsible for excitation. As a result of this work he won the Stokes Studentship at Pembroke College in 1929. He spent 2 years at the Johnson Foundation in Philadelphia before returning to a Research Fellowship at Cambridge University. He went to University College Hospital in 1931 to study clinical medicine before obtaining a Lectureship at Cambridge University in 1935 after which he produced a prodigious body of work; he published 37 papers on nerve with 4 colleagues over 25 years and 147 papers on vision with 27 colleagues over a period of 30 years. Upon retirement he spent some time at Florida State University as a Distinguished Research Professor. He was awarded the Royal Medal of the Royal Society in 1970 and continued to publish until he died in June 1980.

Nervous Excitation

Rushton laid the groundwork for the establishment of the modern theory of nervous excitation and propagation by his quantitative analysis of the temporal and spatial factors involved in electrical excitation [1, 2].

Retinal Densitometry

He developed techniques to measure the visual pigments in vivo. And made important contributions regarding the distribution of pigments in the retina, the action spectrum of bleaching, and the spectral characteristics of bleaching [3, 4, 5].

Cone Pigments

By 1955, Rushton had evidence of visual pigments at the fovea in normal and color-blind subjects. He obtained evidence of two pigments in the medium-long wavelength spectrum in color normals and demonstrated that protonopes and deuteranopes were each lacking one of these pigments [6, 7].

Analytical Anomaloscope

In the early 1960s, Rushton developed an analytic anomaloscope to study color vision. Using this instrument, observers would match a pure spectral light with an additive mixture of red and green in variable proportions [8].

Principle of Univariance

Rushton published two papers in Scientific American and gave several notable didactic lectures. In a review lecture at the Physiological Society (London), he described the principle of univariance that: “the output of a receptor depends upon its quantum catch, but not upon which quanta are caught.” Many of the laws of color mixing are a direct consequence of this principle. He also reintroduced the cone pigment triangle, first put forward by Maxwell, as an alternative to the usual representation of color space developed by the CIE [9].


  1. 1.
    Rushton, W.A.H.: The time factor in electrical excitation. Biol. Rev. 10, 1–17 (1935)CrossRefGoogle Scholar
  2. 2.
    Rushton, W.A.H.: A theory of excitation. J. Physiol. Lond. 84, 42P (1935)Google Scholar
  3. 3.
    Campbell, F.W., Rushton, W.A.H.: The measurement of rhodopsin in the human eye. J. Physiol. Lond. 126, 36P–37P (1954)Google Scholar
  4. 4.
    Campbell, F.W., Rushton, W.A.H.: Measurement of scotopic pigment in the living human eye. J. Physiol. Lond. 130, 131–147 (1955)Google Scholar
  5. 5.
    Rushton, W.A.H.: The difference spectrum and the photosensitivity of rhodopsin in the living human eye. J. Physiol. Lond. 134, 11–29 (1956)CrossRefGoogle Scholar
  6. 6.
    Rushton, W.A.H.: A cone pigment in the protonope. J. Physiol. Lond. 168, 345–359 (1963)CrossRefGoogle Scholar
  7. 7.
    Rushton, W.A.H.: A foveal pigment in the deuteranope. J. Physiol. Lond. 176, 24–37 (1965)CrossRefGoogle Scholar
  8. 8.
    Baker, H.D., Rushton, W.A.H.: An analytical anomaloscope. J. Physiol. Lond.168, 31P–33P (1963)Google Scholar
  9. 9.
    Rushton, W.A.H.: Pigments and signals in colour vision (Review Lecture). J. Physiol. Lond. 220, 1P–31P (1972)CrossRefGoogle Scholar

Further Reading

  1. Barlow, H.B.: William Rushton. 8 December 1901–21 June 1980. Biograph. Mem. Fellows R. Soc. 32, 422–426 (1986)Google Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Colour Science and TechnologyUniversity of LeedsLeedsUK