Figure 1.
Examples of the type of face stimuli used.
The top row shows the lowest oxygenated blood colour of the stimuli tested, while the bottom row shows the highest. The colour difference between the top and bottom rows is 4.8 (ΔE). These images were averaged from several faces and were not used in the actual experiment, but accurately represent how faces were presented and show the colour difference at the extreme ends of the colour continuums.
Figure 2.
Discrimination thresholds and standard error in terms of ΔE values for redness, health, and attractiveness discrimination.