Article Figures & Data
Figures
- Figure 1.
Overview of the task and representative results. A, Subject was instructed to follow a jumping black dot with their eyes. A variable time after the dot jumped horizontally, a vertical bar was flashed for one frame. The bar was presented in one of three possible locations. Subjects were either asked to indicate on which background color they had perceived the bar or to indicate the location of the bar by touching that location. B, The number of flashes for which a representative subject named the correct (green) or incorrect (red) background color for flashes at −2.4°, as a function of the time of the flash (relative to saccade onset). Gray shading indicates the average saccade duration. C, The indicated location of the bar for the same subject as in B. The curved lines are averages based on a moving Gaussian window (σ = 7 ms). Black line, Orientation on a representative trial; dotted lines, the three flash positions; dashed lines, location of the start of and target for the saccade.
- Figure 2.
Percentage of trials in which the subjects perceived the flash on a differently colored part of the background. A, Percentage of trials in which subjects named the color of the background incorrectly. B, Percentage of trials in which subjects localized the bar at a position with the wrong background color. Purple, violet, and blue shading indicates SEM across subjects. Gray shading indicates the average saccade duration. Asterisks indicate times at which the percentages are significantly larger than zero (across subjects, p < 0.05).
- Figure 3.
A simple model that can account for the mislocalization pattern. A, Combining a normally distributed temporal uncertainty (illustrated in pink for two moments of the flash; σt = 15 ms; top, μt = 10 ms; bottom, μt = 30 ms) with the eye orientation, gives the likely distribution of eye orientations shown on the left (orange). Note that the mean values of the orientations (arrows at 2.9° and 6.6°) do not correspond with the orientations of the eye (blue dots at 1.1° and 7.5°). B, Combining these orientation distributions with the retinal stimulation gives likely distributions for the position of the flashed object in space for each moment of time. The means of the distributions for the three locations (curved lines) look similar to the mislocalization curves that are found when one performs these kinds of experiments in the dark. C, The mislocalization curves are different if the distribution for the position of the flashed object in space is combined with a foveal bias (σs = 5°), centered where an efferent eye signal that precedes the actual eye movement by 20 ms indicates that the eye is looking. Note the resemblance with Figure 1C.
