Abstract
Saccades cause relativistic compression of time as well as space
There is now considerable evidence that space is compressed when stimuli are flashed shortly before or after the onset of a saccadic eye movement (Ross, Morrone & Burr Nature 384, 598–601, 1997). The compression is predominantly one-dimensional, parallel to the path of the saccade. New experiments show that not only is space compressed by saccades, but so too is time: the apparent temporal separation of two briefly-flashed bars is halved when they are presented near saccadic onset. Estimates of temporal separation at this time are also more precise, remaining proportional (following Weber's Law) to the perceived rather than the actual temporal separation. More surprisingly, in a critical interval before saccades, perceived temporal order is sometimes consistently reversed: the bar presented second being reported as seen before the first. Taken together, the spatial and temporal phenomena accompanying saccades strongly suggest that vision may be subject to relativistic effects, similar to physical relativistic effects that occur at speeds approaching the speed of light. In many visual areas, neural receptive fields shift peri-saccadically to offset the effect of saccades. This dynamic coordinate transformation is rapid, approaching the physical limit of neural information transfer, hence producing relativistic consequences in both space and time. Transient stimuli captured during the dynamic coordinate transformation will be measured against spatial and temporal scales that are dilated by the Lorentz transform, and will therefore appear compressed in one spatial dimension and in time.