Article Figures & Data
Figures
- Figure 1.
Schematic stimulus design and SSVEP topography. A, Schematic stimulus design. Each trial lasted for 4100 ms and started with the presentation of a scrambled version of an IAPS picture. After a variable interval, the scrambled picture changed to the concrete version for 200 ms in four steps and back to a new scrambled form again in four steps. Subjects attended to the flickering and moving dots to detect and to respond to intervals of coherent motion of a subset of dots. B, Grand mean spline interpolated voltage map of SSVEP amplitude across all subjects and experimental conditions averaged across the whole analysis epoch. Electrode Oz with greatest SSVEP amplitude is indicated.
- Figure 2.
Time course of SSVEP amplitudes and hit rates and source localization of SSVEP emotion effects. A, Baseline corrected time course of SSVEP amplitudes across all subjects at electrode location Oz for trials with neutral (black line) and emotional (gray line) background pictures. Time point zero indicates the onset of a concrete picture. Picture offset is also indicated. Vertical lines indicate the time window from 474 to 744 ms after onset of the concrete picture with significant differences between neutral and emotional background pictures. B, Time course of mean target hit rates across subjects before (first two windows) and after the change. The change covered the time windows from 0 to 100 ms and ended right with the start of the window from 200 to 300 ms. Significant differences in hit rates between trials with neutral and emotional background pictures are indicates with * (p < 0.05). Error bars correspond to 95% within-subject confidence intervals. C, Statistical parametric maps of the cortical current-density distributions giving rise to the SSVEP-amplitude differences between conditions with neutral and emotional background pictures in the time range from 450 to 750 ms after picture onset. The scale represents t2 values, and the threshold of 9.0 corresponds to p < 0.001, corrected for multiple comparisons.
