Cyclopean flash-lag illusion.

Dylan Nieman; Romi Nijhawan; Beena Khurana; Shinsuke Shimojo

doi:10.1016/j.visres.2006.06.003

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Cyclopean flash-lag illusion.

Dylan Nieman·Romi Nijhawan·Beena Khurana·Shinsuke Shimojo

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Abstract

Possible physiological mechanisms to explain the flash-lag effect, in which subjects perceive a flashed item that is co-localized with a moving item as trailing behind the moving item, have been found within the retina of lower species, and in the motor pathways of humans. Here, we demonstrate flash-lag employing "second-order" moving and flashed stimuli, defined solely by their binocular-disparity, to circumvent any possible "early" contributions to the effect. A significant flash-lag effect was measured with cyclopean stimuli composed entirely of correlated random dot patterns. When the disparity-defined moving stimulus was replaced with a luminance-defined one, potentially engaging retinal mechanisms, the magnitude of the measured effect showed no significant change. Thus, in primates, though retinal mechanisms may contribute, flash-lag must be explained through cortical processes.

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Adaptation, Ocular Cerebral Cortex Humans Judgment Light Motion Perception Optical Illusions Photic Stimulation Psychometrics Retina Vision Disparity Vision, Binocular Journal Article

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Dylan Nieman, Romi Nijhawan, Beena Khurana, Shinsuke Shimojo. 2006-07-18. Cyclopean flash-lag illusion.. https://doi.org/10.1016/j.visres.2006.06.003

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