Foveal inhibition measured with suprathreshold stimuli

Foveal inhibition has been studied with elementary stimuli presented at increment threshold luminance and with suprathreshold stimuli. Both kinds of stimuli yield a similar kind of propagating inhibition. The results of this study are compared with previously published data on peripheral inhibition. The inhibition produced with spatially extended stimuli is described in terms of the ideas derived from measurements on elementary stimuli. This model is tested for a metacontrast stimulus consisting of a disk which is followed after a certain delay by a ring surrounding the disk.