It is possible that human preferences for redness may reflect a sensory bias, in which case any perceptible change in red colour could affect perceived health or attractiveness.
The underlying blond trait did not significantly reduce the area of blotching but did reduce the saturation (paler blotching) and enhanced the redness of body colour in the homozygous blond fish compared to the heterozygous (wild type) group.
The current study used a two-alternative forced choice (2AFC) psychophysics design to quantify the oxygenated blood colour (redness) change threshold required to affect perception of facial colour, health and attractiveness.
All assess symptoms including inflammation, redness (erythema) or colour compared with the surrounding skin, size, scar contour, dryness and itchiness (pruritus).
However, bentonite decreased the a* meat colour parameter (redness; P=0.004).
Magnetic properties are compared to the redness rating of soil colour, which is related to the hematite content and is an established proxy for soil weathering.
If they chose the face with higher redness four consecutive times, the colour threshold would be recorded as 0.075 (the colour difference between each interval in the continuum).
No inflammation – healthy gingiva Mild inflammation – slight change in colour and in tissue structure; no bleeding on probing Moderate inflammation – visible glazing, redness, oedema, and hypertrophy; bleeding on pressuring or probing, Severe inflammation – marked redness and hypertrophy; tendency towards spontaneous bleeding; ulceration.
pectoralis) and both whole thighs (bone and muscles) were cut from the carcass and evaluated for muscle colour, lightness (L*), redness (a*) and yellowness (b*) using reflectance colorimetry (Minolta CR-300, CIELab, Minolta (UK) Limited, Milton Keynes, UK).
