Article Figures & Data
Figures
- Figure 1.
A, Time course of a single trial. The red dot represents the current eye position. After a go signal, participants performed a saccade toward a target placed either on the left or on the right of a central fixation point. At saccade onset the target disappeared and reappeared 50 ms after at the same place (no displacement, 50%) or at a distance d away from the initial position (displacement condition, 25% backward, 25% forward). Participants reported whether the target moved. B, Average distance thresholds d in degrees of visual angle measured in the staircase task. C, Average sensitivity d′ to target displacements. D, Decision criterion. All averages were calculated across participants, and each point represents an individual observer (B–D). E, Individual distributions of landing errors and the box plot of median error across participants. Negative values represent undershoots and positive value overshoots. F, Relationship between post-saccadic landing error and adjustment in subsequent saccadic amplitude. Lines represent their linear relationship for each participant, displacement condition (Backward/No displacement/Forward) and response type (No/Yes). G, Median amplitude residuals of the linear relationship of saccadic adjustment and post-saccadic landing errors separated by displacement condition (Backward, No-displacement, Forward) across participants. Post-saccadic errors were not enough for explaining the saccadic adjustment as the actual adjustment is below/above the expected in the forward/backward conditions, respectively. This intuition can be extracted from F as well, where at no adjustment (y = 0), participants systematically had more positive errors (overshoots) in backward trials than in no-displacement trials, and more negative errors (undershoots) in forward trials. H, Distribution of the median absolute post-saccadic error (PSE) for hits, false alarms (FA), misses, and correct rejections (CR) across participants.
- Figure 2.
Decoding displacements from the EEG signal. Left, Dotted vertical lines represent saccade detection (at 0 s) and target reappearance (at 0.05 s). Thick lines represent time points at which classification performance differs from chance (AUC = 0.5). Right, Topographic activation maps at four time windows, with the significant channels highlighted. The color map ranges from −10 (cool colors) to 10 (warm colors) arbitrary units.
- Figure 3.
A, Decoding displacements from the eye position data. Dashed lines and shaded areas as in Figure 2. B, Eye position data of participant 1 at 50 ms (target reappearance) and at 600 ms (right before the response go signal). The y-axis is the vertical position on the screen, whereas the x-axis is the distance from the center of the screen, the initial fixation. The plus signs represent the three possible positions of the target across trials (backward displacement, no-displacement, forward displacement). The gaze of participant 1 in all trials is represented by the dots. The dot color represents if there was a displacement (red) or not (blue) in each trial. As in A, for participant 1, there is a clear boundary for classifying the displacement from the eye position at the end of the trial (600 ms) but not at the beginning when the target just reappeared (50 ms), meaning that participant 1 generally performed eye movements toward the target at some point of the trial.
Tables
Model AIC BIC Full behavioral 99012.465 99085.850 True decoding 101140.834 101214.219 Null behavioral 101210.495 101254.525 Shuffled decoding 101199.043 101272.427 Smaller values correspond to better fits.
