Monoptic and dichoptic metacontrast across the vertical meridian

'U'-shaped backward contour masking during stroboscopic motion.

“…Finally, it is noteworthy that all of the presently reported stimulus interactions were obtained across the vertical meridian. In metacontrast such interactions between target and mask have also been reported by McFadden and Gummerman (1973). This, according to the conventional view (Gazzaniga, 1967;Sperry, 1974) could be interpreted to mean that the present effects are due to interhemispheric interactions, since according to that view stimuli presented to the left and right of fixation are processed by the right and left hemispheres, respectively.…”

Integrative and interruptive mechanisms in peripheral and hemispheric masking

“…The experiment was similar to other masking studies that varied the location of the stimulus presentations in the visual fields (Lefton, 1972;McFadden & Gummerman, 1973;Polich, 1978;Proudfoot , 1982;Saccuzzo et al, 1982;Ward & Ross, 1977), and it is a partial replication of the work by Saccuzzo et al that examined masking in higher cortical regions . It is believed that presentations to opposite visual fields result in contralateral stimulus projections beyond Area 17 in the visual cortex (McFadden & Gummerman, 1973;Saccuzzo et al, 1982). In addition to using color stimuli, this experiment included a homogeneouslight-maskcontrol to rule out light masking as an alternative explanation for the findings of Saccuzzo et al A backward-masking function was expected for opposite visual field stimulus presentations using the black mask.…”

Neuronal correlates of visibility and invisibility in the primate visual system

“…We chose to examine these effects in primates because the psychophysics of visual masking in primates is similar if not identical to that of humans 23 . We studied area V-1 because previous psychophysical studies found that perception of a target presented to one eye can be blocked by a mask presented to the other eye [24][25][26][27] , suggesting that masking is induced in the cortex, where inputs from the two eyes are first combined 39 . First we characterized the receptive field of each single unit (or sometimes multiple-unit activity), with a combination of hand mapping and eye-position-corrected, reverse-correlation methods 21,22 .…”