Masking produces compression of space and time in the absence of eye movements

Abstract

Whenever the visual stream is abruptly disturbed by eye movements, blinks, masks, or flashes of light, the visual system needs to retrieve the new locations of current targets and to reconstruct the timing of events to straddle the interruption. This process may introduce position and timing errors. We here report that very similar errors are seen in human subjects across three different paradigms when disturbances are caused by either eye movements, as is well known, or, as we now show, masking. We suggest that the characteristic effects of eye movements on position and time, spatial and temporal compression and saccadic suppression of displacement, are consequences of the interruption and the subsequent reconnection and are seen also when visual input is masked without any eye movements. Our data show that compression and suppression effects are not solely a product of ocular motor activity but instead can be properties of a correspondence process that links the targets of interest across interruptions in visual input, no matter what their source.