RT Journal Article
A1 Zele, Andrew J.
A1 Maynard, Michelle L.
A1 Feigl, Beatrix
T1 Rod and cone pathway signaling and interaction under mesopic illumination
JF Journal of Vision
JO JOV
YR 2013
DO 10.1167/13.1.21
JF Journal of Vision
VO 13
IS 1
SP 21
OP 21
SN 1534-7362
AB   This study investigates the time-course and post-receptoral pathway signaling of photoreceptor interactions when the rod (R) and three cone (L, M, S) photoreceptor classes contribute to mesopic vision. A four-primary photostimulator independently controls photoreceptor activity in human observers. The first experiment defines the temporal adaptation response of receptoral (L-, S-cone, rod) and post-receptoral (LMS, LMSR, +L-M) signaling and interactions. Here we show that nonopponent cone-cone interactions (L-cone, LMS, LMSR) have monophasic temporal response patterns whereas opponent signals (+L-M, S-cone) show biphasic response patterns with slower recovery. By comparison, rod-cone interactions with nonopponent signals have faster adaptation responses and reduced sensitivity loss whereas opponent rod-cone interactions are small or absent. Additionally, the rod-rod interaction differs from these interaction types and acts to increase rod sensitivity due to temporal summation but with a slower time course. The second experiment shows that the temporal profile of the rod signal alters the relative rod contributions to the three primary post-receptoral pathways. We demonstrate that rod signals generate luminance (+L+M) signals mediated via the MC pathway with all rod temporal profiles and chromatic signals (L/L+M, S/L+M) in both the PC and KC pathways with durations >75 ms. Thus, we propose that the change in relative weighting of rod signals within the post-receptoral pathways contributes to the sensitivity and temporal response of rod and cone pathway signaling and interactions. 
RD 7/24/2019
UL https://doi.org/10.1167/13.1.21