Data from: Interaction between stimulus contrast and pre-saccadic crowding

Objects that are briefly flashed around the time of saccades are
mislocalized. Previously, robust interactions between saccadic perceptual
distortions and stimulus contrast have been reported. It is also known
that crowding depends on the contrast of the target and flankers. Here, we
investigated how stimulus contrast and crowding interact with pre-saccadic
perception. We asked observers to report the orientation of a tilted Gabor
presented in the periphery, with or without four flanking vertically
oriented Gabors. Observers performed the task either following a saccade
or while maintaining fixation. Contrasts of the target and flankers were
independently set to either high or low, with equal probability. In both
the fixation and saccade conditions, the flanked conditions resulted in
worse discrimination performance—the crowding effect. In the unflanked
saccade trials, performance significantly decreased with target-to-saccade
onset for low-contrast targets but not for high-contrast targets. In the
presence of flankers, impending saccades reduced performance only for
low-contrast, but not for high-contrast flankers. Interestingly, average
performance in the fixation and saccade conditions was mostly similar in
all contrast conditions. Moreover, the magnitude of crowding was
influenced by saccades only when the target had high contrast and the
flankers had low contrasts. Overall, our results are consistent with
modulation of perisaccadic spatial localization by contrast and saccadic
suppression, but at odds with a recent report of pre-saccadic release of
crowding.