Location of Repository

Dark-adapted rod suppression of cone flicker detection : evaluation of receptoral and postreceptoral interactions

By Dingcai Cao, Andrew J. Zele and Joel Pokorny

Abstract

Dark-adapted rods in the area surrounding a luminance-modulated field can suppress flicker detection. However, the characteristics of the interaction between rods and each of the cone types are unclear. To address this issue, the effect that dark-adapted rods have on specific classes of receptoral and postreceptoral signals was determined by\ud measuring the critical fusion frequencies (CFF) for receptoral L-, M-, and S-cone and postreceptoral luminance\ud ([L+M+S] and [L+M+S+Rod]) and chromatic ([L/L+M]) signals in the presence of different levels of surrounding rod activity. Stimuli were generated with a two-channel photostimulator that has four primaries for a central field and four primaries for the surround, allowing independent control of rod and cone excitation. Measurements were made either with adaptation to the stimulus field after dark adaptation or during a brief period following light adaptation. The results show that dark-adapted rods maximally suppressed the CFF by ~6 Hz for L-cone, M-cone, and luminance modulation. Dark-adapted rods, however, did not significantly alter the S-cone CFF. The [L/L+M] postreceptoral CFF was slightly suppressed at higher surround illuminances, that is, higher than surround luminances resulting in suppression for L-cone, M-cone, or luminance modulation. We conclude that rod-cone interactions in flicker detection occurred strongly in the magnocellular pathway

Publisher: Cambridge University Press
Year: 2006
DOI identifier: 10.1017/S0952523806233376
OAI identifier: oai:eprints.qut.edu.au:7470

Suggested articles

Preview


To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.