Inter-species variation in colour perception

Colour perception in pseudophakia.

Minor differences in colour perception between pseudophakic, phakic, and spectacle aphakic eyes were identified by the Pickford-Nicholson anomaloscope and the Farnsworth-Munsell 100-hue test. The results suggest that pseudophakic eyes are more sensitive to red and less sensitive to blue than aphakic eyes corrected with spectacles. Spectrophotometer measurements reveal that the Rayner-Pearce pos...

Colour perception in ADHD.

Attention-deficit/hyperactivity disorder (ADHD) is associated with unexplained impairments on speeded naming of coloured stimuli. These deficits may reflect hypofunctioning retinal dopaminergic mechanisms impairing particularly blue-yellow colour discrimination. Colour perception and rapid colour naming ability were investigated in 14 children with ADHD and 13 healthy peers matched for age, gen...

Colour Perception, and Colour-Blindness Tests

Colour perception in a dichromat.

Most mammals have dichromatic colour vision based on two different types of cones: a short-wavelength-sensitive cone and a long-wavelength-sensitive cone. Comparing the signal from two cone types gives rise to a one-dimensional chromatic space when brightness is excluded. The so-called ;neutral point' refers to the wavelength that the animal cannot distinguish from achromatic light such as whit...

Optimum probabilistic processing in colour perception. I. Colour discrimination.

A comprehensive account of wavelength discrimination and colour saturation discrimination is given in terms of optimum probabilistic signal detection. The theory is a logical deduction from statistical estimation theory of the visual estimate of the spectral parameters of the stimulus. In place of geometrical concepts associated with colour-space geometry, stimulus discriminability is determine...