THE DETERMINANTS OF GROUPING DURING BINOCULAR RIVALRY

Interocular grouping during binocular rivalry occurs when two images concurrently presented to two eyes are combined as a coherent pattern as if perceptual experience follows Gestalt grouping principles. The present study investigated what determines rivalry dynamics (perceptual experience of monocular stimuli and interocular grouping) by examining individual differences. Specifically, the effect of eye-of-origin and pattern coherence on percepts during rivalry were individually assessed using pairs of stimuli that induce either monocularly-driven (monocular coherence condition) or interocularly-driven (interocular coherence condition) coherent percepts. We found that the degree of perceiving complete, coherent stimuli was consistent within individuals regardless of conditions, indicating that individual differences in experiencing interocular grouping were explained by pattern coherence, rather than eye-of-origin information. In addition, we found that individuals who experience binocularly presented pattern motion more perceived interocularly-coherent stimuli more. This result suggests that a potential common mechanism may mediate binocular integration of visual information during binocular rivalry.