Figure 1.
Time-estimation task with interspersed stop-signal trials.
The tactile time-estimation task included three conditions (control, easy, hard) with different response-window adaptations leading to different error-rates (see text for details). In the randomly assigned stop-signal trials prior to response execution a stop-signal indicated the need to inhibit the response. Hand symbols from ITT Bombay (www.designofsignage.com).
Figure 2.
72 of the 80 EEG-electrodes used are depicted. The 15 central electrodes were used to compare the peak-amplitudes and topographies of the ERPs. For the Global Map Dissimilarity measure all 80 electrodes were included in the analyses.
Table 1.
Number of trials for ERP analysis.
Figure 3.
ERP data associated with performance-feedback in the time-estimation task (FRN).
A: Scalp topographies for the left and right hand unexpected difference wave FRN peaks and histogram of the Global Map Dissimilarity permutation test between these two topographies. B; SWARM solution for the FRN revealing an aMCC source. C: Difference wave for expected and unexpected outcomes as observed at channel FCz. Tactile performance feedback was received at 0 on the abscissa. Note that negative voltages are plotted upwards by convention.
Figure 4.
ERP data associated with successful inhibition after a stop-signal cue (N2).
A: Scalp topographies for the left and right hand N2 peaks and histogram of the Global Map Dissimilarity permutation test between these two topographies. B: SWARM solution for the N2 revealing the aMCC as well the right inferior frontal cortex as source. C: ERPs recorded at channel FCz. Tactile stop-signal cue given at 0 on the abscissa.
Figure 5.
ERP data associated with the action-slip following a stop-signal cue (ERN).
A: Scalp topographies for the left and right hand ERN peaks and histogram of the Global Map Dissimilarity permutation test between these two topograhies. B: SWARM solution for the ERN showing the aMCC as source. C: ERPs recorded at channel FCz. Responses were recorded at 0 on the abscissa.
Figure 6.
Performance data in the time-estimation task.
Absolute changes in response time following expected (correct easy trials and erroneous hard trials) and unexpected outcomes (correct hard trials and erroneous easy trials).
Table 2.
ERP amplitudes at electrode FCz.
Table 3.
FRN-related ANOVA with factors Expectancy (Expected, Unexpected), Hand (left, right), A-P, and Laterality.
Table 4.
N2-related ANOVA with factors Hand, A-P, and Laterality.
Table 5.
ERN-related ANOVA with factors Hand, A-P, and Laterality.
Table 6.
Global Map Dissimilarity scores comparing the ERPs.
Figure 7.
Regression analyses between FRN, N2, and ERN.
Peak amplitudes of the ERPs were z-normalized. Bivariate regression analyses between the N2 and ERN revealed a strong relationship (β = .755; SEM = .140; t = 5.407; p<.001) between the N2 and ERN, and much less shared variance between the N2 and FRN (β = .426; SEM = .193; t = 2.21; p = .038). Coefficents of the bivariate regression between ERN and FRN are in between the aforementioned ones (β = .553; SEM = .178; t = 3.11; p = .005).