We explored the neural basis for spatial color contrast (red looks redder surrounded by green) and temporal color contrast (red looks redder if preceded by green) in primary visual cortex (V1) of the alert macaque. Using pairs of stimuli, we found a subset of neurons that gave stronger responses to sequences of red and green spots and stronger responses to adjacent red and green spots. These ce...

In many languages there are concepts for warm and cold colors. Research on color-temperature correspondence and their interaction is quite scarce, and based mostly on subjective measures. It is still unknown whether and to what extent colors bear the thermal information. The current study explored the relationship between warm and cold colors (red and blue) and thermal aspects of the word seman...

OBJECTIVE The aim was to evaluate the color and surface roughness of nanoparticle (C1) and nanohybrid (C2) composites after immersion in distilled water, acai juice, grape juice and red wine and repolishing. MATERIALS AND METHODS After recording the initial surface roughness and color, the specimens were divided into four groups according to the storage solution. The specimens were reassessed...

It is generally held that protanopes and deuteranopes see only regions of blues and yellows in the visible spectrum, with an achromatic point, called the neutral point, separating these regions. Considerations of a zone model of color vision for the dichromatic observer led us to predict that a reduced form of red/green discrimination would allow equilibrium blue judgements to be made by protan...

In contrast to the short-duration and quick reversibility of attention, a long-term sensitization to color based on protracted attention in a visual search task was reported by Tseng, Gobell, and Sperling (2004). When subjects were trained for a few hours to search for a red object among colored distracters, sensitivity to red was increased for weeks. This sensitization was quantified using amb...

PURPOSE To develop and assess new color vision tests to be used in evaluating faulty color recognition. METHODS We developed new color vision tests to evaluate faulty color recognition. The two types of color vision tests, designed to assess faulty color recognition in color vision deficiencies, are based on principles that are different from those of the conventional color vision tests. In t...

The objective of this project is to establish a practical application of the concept of Color Universal Design (CUD), the design that is recognizable to all color vision types. In our research, we looked for a clearly distinguishable combination of hues of four colors – black, red, green, and blue – which are frequently used in these circumstances. Red-green confusion people do not confuse all ...

PURPOSE To examine experimentally whether color vision deficiency confers a selective advantage under scotopic conditions. METHODS Red-green color-deficient subjects, monochromats, and age-matched color-normal control subjects were examined. In each subject the time course of dark adaptation, scotopic visual field sensitivity, and performance on a scotopic perceptual task were measured. RES...

Around 2% of males have red-green dichromacy, which is a genetic disorder of color vision where one type of cone photoreceptor is missing. Here we investigate the color preferences of dichromats. We aim (i) to establish whether the systematic and reliable color preferences of normal trichromatic observers (e.g., preference maximum at blue, minimum at yellow-green) are affected by dichromacy and...

Physiological studies of color have uncovered many puzzles. Here are four puzzles. First, neurons in the lateral geniculate nucleus (LGN; Fig. 1) are strongly color opponent, but the opponency does not correspond to Hering's fundamental opponent-color pairs (red–green, blue–yellow) (Webster et al., 2000); moreover, the color-tuning of the population of LGN cells is not balanced across color spa...