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It is now well established that briefly flashed single targets are mislocalized in space, not only during saccades but also before them. We show here by several techniques (including a vernier judgment that did not require absolute location in space) that errors appear up to 100 msec before saccades are made and are maximal just before they start. The size(More)
Visual scientists have long sought to explain why the world remains stable during saccades, the ballistic eye-movements that continually displace the retinal image at fast but resolvable velocities. An early suggestion was that vision may be actively suppressed during saccades, but experimental support has been variable. Here we present evidence that(More)
We measured the time course of saccadic suppression and tested whether suppression results entirely from retinal image motion or has an extraretinal source. We measured contrast thresholds for low-frequency gratings modulated either in luminance, at 17 cd/m(2) and 0.17 cd/m(2), or color at 17 cd/m(2). Gratings were flashed on a uniform background before,(More)
After a preliminary study of visual evoked potentials (VEPS) to a test grating seen in the presence of masks at different orientations, psychophysical data are presented showing the effects of adaptation and of masking on thresholds for detecting the same test grating. The test is a vertical grating of spatial frequency 2 cycles per degree; adapting and(More)
There is now considerable evidence that space is compressed when stimuli are flashed shortly before or after the onset of a saccadic eye movement. Here we report that short intervals of time between two successive perisaccadic visual (but not auditory) stimuli are also underestimated, indicating a compression of perceived time. We were even more surprised(More)
We investigated the spatial parameters that permit temporal phase segmentation. Subjects identified a stimulus quadrant which was modulated 180 degrees out of phase with the rest of the stimulus at temporal frequencies between 2 and 30 Hz. We determined the modulation sensitivity for regular square lattices of Gaussian spots and a stimulus made from solid(More)
We frequently reposition our gaze by making rapid ballistic eye movements that are called saccades. Saccades pose problems for the visual system, because they generate rapid, large-field motion on the retina and change the relationship between the object position in external space and the image position on the retina. The brain must ignore the one and(More)
Measurements were made of the contrast required to see the direction of motion of drifting gratings (Part 1) and of moving bars (Part 2). The spatial frequency at which least contrast is required to see sinusoidal gratings decreases as their velocity increases, but peak sensitivity is identical at all velocities up to 800 deg/sec. Similarly, the wider a(More)