Article Figures & Data
Figures
- Figure 1.
Experimental setup and eye-movements behavior. A, Trial time course. B, C, Each set of two panels represents what is presented to each eye with the shutter glasses. After a fixation interval, a stimulus appeared monocularly in the periphery (top). After the disappearance of the fixated crosshair, the subjects perform a saccade to the center of the presaccadic stimulus, which becomes the postsaccadic stimulus (bottom). The colored circles represent the location of the blind spot in each eye and were not displayed on the screen. B, An example of a trial without change: the inset stimulus, presented outside the blind spot, does not change before and after the saccade. Importantly, presenting an inset stimulus inside the blind spot always leads to fill-in and therefore the perception of a continuous stimulus. We therefore recorded the inset no-change condition only outside the blind spot. C, A trial with change: the continuous stimulus, presented inside the blind spot, is exchanged during the saccade to an inset stimulus. D, Gabor patches used as stimuli; horizontal stimuli were also used. The inset was set to ∼50% the diameter of the blind spot. E, Locations of the blind spots and saccades' end-points. The gray ring encloses the tolerance area for fixation. The gray discs represent the average calibrated blind spot sizes and locations for each subject. Bold crosses represent the winsorized average saccade end locations over subjects of both inside and outside blind spot trials (±winsorized SD). Small crosses show the same metrics for each individual subject. F, The design matrix used for the single subject GLMs. An overparameterized model of four main effects (purple), constant, and all interactions (green) was used.
- Figure 2.
Main factor blind spot. Time-series plots of the EEG β weights of the main factors or interactions for each electrode are shown (butterfly plot), aligned to the onset of the presaccadic stimulus. Blue marked latencies are significant under TFCE α of 0.05 and, therefore, are corrected for multiple comparisons over time points and electrodes. Black marked latencies are significant under additional Bonferroni correction for the testing of multiple factors in a model. This second procedure is overly conservative and only done to evaluate the robustness of the effects. The first row of the topographical plots represents the mean β weights averaged over 50 ms bins. The second row depicts the minimal TFCE-corrected p values over the same bin. Black marked electrodes represent significant channels. The location of the red highlighted channel is depicted in the first topographic plot. A, The main effect Blind spot depicts the difference of a presaccadic stimulus presentation inside and outside the blind spot, which is prominent 200 ms after stimulus onset. B, The main effect of Position shows a contralateral processing in occipital electrodes to a stimulus presented in the periphery. C, The Blind Spot × Position interaction depicts a lateral component of the effect shown in A.
- Figure 3.
Main effect of change and interaction with the blind spot. Data aligned to saccade offset when the stimulus is foveated. A, The main effect Change is shown, comparing trials in which the stimulus remained the same, with trials, where it changed during the saccade. The effect resembles a prediction error in the form of a P3. B, The interaction Blind spot × Change is shown. This shows a reduction of the prediction error described in A. C, Correlation of each subject effect-template with ERP data over 10 partitions of the experiment. The red correlation shows that the main effect of change habituates over the course of the experiment. The blue correlation shows no significant increase or decrease for the Change × Blind spot interaction and thus stays stationary over the experiment. D, Raw ERP data of the interaction depicted in B. The top row depicts outside the blind spot data and the bottom row depicts inside the blind spot data. The difference of the change effect inside blind spot against outside blind spot was tested using a bootstrapped Yuen's t test and corrected for multiple comparisons using TFCE. The significant electrodes and time-points can be seen as black dots. This confirms the reduction of the P3 inside the blind spot.
- Figure 4.
Middle and early latency interaction with the change factor. Data aligned to the saccade offset when the stimulus is foveated A, The Change × Position interaction shows a clearly lateralized prediction error at ∼200 ms. The two histograms insets depict saccade onset and stimulus change, and show that all changes occurred during the saccades. B, The Change × Inset interaction shows three separate effects. Detailed descriptions are found in Results. C, The Change × Inset × Position interaction shows an early prediction error that is lateralized and also dependent on the low-level stimuli properties.
