Prereceptor colour vision distortions in protanomalous trichromacy

Colour-Vision and Colour-Blindness

Colour vision

The immense range of colours that we see belies the relative simplicity of the system underlying colour vision. We see colours because each of the three distinct types of cone photoreceptor in our retinae is sensitive to a different range of wavelengths of light. The L, M and S cones, colloquially called red (R), green (G), and blue (B), are selective for long, middle and short wavelengths, res...

Colour vision

Editorial Colour vision 2006 is an important bicentenary for the Ulster Medical Society. In 806, the Belfast Medical Society was founded and the later formation of the Belfast Clinical and Pathological Society in 853, allowed amalgamation of both societies to form the current Ulster Medical Society in 862. The vision of the early founders of the Belfast Medical Society, was far sighted, and som...

Colour vision in billfish.

Members of the billfish family are highly visual predatory teleosts inhabiting the open ocean. Little is known about their visual abilities in detail, but past studies have indicated that these fishes were likely to be monochromats. This study, however, presents evidence of two anatomically distinct cone types in billfish. The cells are arranged in a regular mosaic pattern of single and twin co...

The dimensionality of color vision in carriers of anomalous trichromacy.

Some 12% of women are carriers of the mild, X-linked forms of color vision deficiencies called "anomalous trichromacy." Owing to random X chromosome inactivation, their retinae must contain four classes of cone rather than the normal three; and it has previously been speculated that these female carriers might be tetrachromatic, capable of discriminating spectral stimuli that are indistinguisha...