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We investigated temporal properties of visual perception as a function of eccentricity, that is, spatial position relative to the fovea. Our experiments were motivated by well-characterized non-uniformities in neuron distribution in the human eye and early visual pathways. These non-uniformities have been extensively studied in the context of spatial perception, while largely neglected in relation to temporal perception. In Experiment 1, participants fixated the rapid serial visual presentation letter stream and were instructed to report the letter which appeared simultaneously with a brief cue presented at different locations along the horizontal meridian. Participants exhibited a tendency to report earlier letters with more peripheral as compared to central cues, indicating that they misperceived differently located stimuli as simultaneous even though they were never presented together. Experiment 2 conceptually replicated the findings of Experiment 1. Experiment 3 further demonstrated that the effect is specifically due to eccentricity, and not the relative distance between the stimuli. We argue that such location-based misperceptions of simultaneity arise because transient stimuli at more eccentric locations advance to perception faster than stimuli at or near the fovea. Collectively, these experiments show, for the first time, how processing speed differences across the visual field translate into differences in perceived simultaneity. They also demonstrate, for the first time, location-based misperceptions of simultaneity for stimuli never presented together. Finally, Experiment 4 showed that greater eccentricity also increased the perceived duration of a stimulus compared to fovea. These results reveal the breadth of perceptual effects driven by temporal processing differences across the visual field. Public Significance StatementHow are events occurring at different times and places integrated into a unified experience of what is happening now? We report experiments that sequester and dissect the visual now, our sense of a present moment in visual experience. In particular, we consider how a moment of visual experience combines events that occur at different times and locations. The results suggest that space and time dissociate as events are stitched into a moment of experience, that a perceived moment can combine stimuli that did not necessarily share an overlapping moment in reality. We explain these results in relation to how neurons in the eye and the brain are distributed to process visual space.

Prior research on film viewing has demonstrated that participants frequently fail to notice spatiotemporal disruptions, such as scene edits in the movies. Whether such insensitivity to spatiotemporal disruptions extends beyond scene edits in film viewing is not well understood. Across three experiments, we created spatiotemporal disruptions by presenting participants with minute long movie clips, and occasionally jumping the movie clips ahead or backward in time. Participants were instructed to press a button when they noticed any disruptions while watching the clips. The results from experiments 1 and 2 indicate that participants failed to notice the disruptions in continuity about 10% to 30% of the time depending on the magnitude of the jump. In addition, detection rates were lower by approximately 10% when the videos jumped ahead in time compared to the backward jumps across all jump magnitudes, suggesting a role of knowledge about the future affects jump detection. An additional analysis used optic flow similarity during these disruptions. Our findings suggest that insensitivity to spatiotemporal disruptions during film viewing is influenced by knowledge about future states.

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