Rod and cone pathway signaling and interaction under mesopic illumination
Data(s) |
16/01/2013
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Resumo |
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 (þLþM) signals mediated via the MC pathway with all rod temporal profiles and chromatic signals (L/LþM, S/LþM) 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. |
Formato |
application/pdf |
Identificador | |
Publicador |
The Association for Research in Vision and Ophthalmology (ARVO) |
Relação |
http://eprints.qut.edu.au/59267/1/Zele_Maynard_Feigl_JoV2013.pdf DOI:10.1167/13.1.21 Zele, Andrew J., Maynard, Michelle L., & Feigl, Beatrix (2013) Rod and cone pathway signaling and interaction under mesopic illumination. Journal of Vision, 13(1). http://purl.org/au-research/grants/ARC/DP1096354 |
Direitos |
Copyright 2013 Association for Research in Vision and Ophthalmology |
Fonte |
School of Biomedical Sciences; Faculty of Health; Institute of Health and Biomedical Innovation; School of Optometry & Vision Science |
Palavras-Chave | #111300 OPTOMETRY AND OPHTHALMOLOGY #mesopic #temporal #adaptation #rod-cone interaction #post-receptoral |
Tipo |
Journal Article |