The effects of peripheral movement and flicker on the detection thresholds of sinusoidal gratings

Abstract

Contrast sensitivity functions were obtained in the presence of temporally modulated surrounds. Sensitivity to low spatial frequencies was depressed below that found with a steady surround when the surround was either a sinusoidally flickering field or a drifting vertical square-wave grating. This effect was observed both with 1-sec presentations of 5- and 0.5-Hz counterphase flicker and with 60-msec pulsed gratings. In addition, reaction time histograms became more characteristic of sustained mechanisms in the presence of temporal modulation. The data were considered in terms of the activity of a nonlinear network of retinal subunits. © 1985 Psychonomic Society, Inc.