Dark versus bright equilibrium hues: rod and cone biases.
Equilibrium (unique) red, green, blue, and yellow stimuli look bright in a black surround, but they look dark in a bright white surround, and yellow changes to brown. We investigated differences in equilibrium-hue chromaticity between bright and dark hues to reveal changes in weighting of cone and rod signals. The largest, most consistent shifts were found between yellow and brown, with equilibrium-brown chromaticity shifted toward red compared to equilibrium yellow at both photopic and mesopic levels. Also, at mesopic levels, rod influence reversed for most observers from a green bias for yellow to a red bias for brown. Bright/dark differences for blue, green, and red were much smaller and/or less consistent. Thus, shifts of cone and rod hue biases between bright and dark hues are most prominent in L-M-cone pathways, especially those activated by yellow and brown stimuli.
Steven L
SL
Buck
Tanner
T
DeLawyer
D000328:Adult; D002540:Cerebral Cortex / Q000166:cytology / Q000502:physiology / Q000528:radiation effects; D003118:Color Perception / Q000502:physiology* / Q000528:radiation effects*; D003624:Darkness; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017949:Retinal Cone Photoreceptor Cells / Q000166:cytology* / Q000528:radiation effects*; D017948:Retinal Rod Photoreceptor Cells / Q000166:cytology* / Q000528:radiation effects*; D055815:Young Adult