Temporal filters underlying flicker detection and identification for red-green and achromatic stimuli

Abstract

Purpose. Does the red-green (RG) cone-opponent system comprise a single temporal filter, or are there multiple underlying temporal frequency (TF) tuned filters as in the achromatic system? To answer this, we determine whether RG color contrast alone is able to support unambiguous encoding of TF. Methods. Using a 2x2-IFC procedure, we simultaneously measured detection and TF identification performance for both RG isoluminant and achromatic stimuli for two observers over a range of TFs (RG: 1, 2, 4, 8, 16 & 22.6 Hz, Ach: 1, 2, 4, 8, 16 & 32 Hz). Stimuli were counterphase flickering 16° Gabor patches viewed foveally on a CRT, with 0.25 c/° carrier spatial frequency and a raised cosine temporal ..