Observations and findings in the present study can also be explained with the conflict monitoring hypothesis as well. More anteriorization was observed for the NoGo N2 with the largest mean amplitude in the frontal regions, which is consistent with previous studies. However, the present study also found the largest mean amplitude of Go N2 in the central regions (second largest was observed in the frontal regions for controls), rather than the traditionally reported parietal (posterior) regions (Figures 3b, 4). Together, these observations suggest increased activity in anterior and central regions during both task conditions, which may be reflecting the detection of conflict between two competing response tendencies. Therefore, the findings of the present study, i.e., both NoGo and Go N2s having largest amplitudes in anterior and central regions, respectively, suggest involvement of an anterior executive conflict monitoring system when a single motor response was to be executed or withheld. Support for the conflict monitoring view gets further strengthened by the sLORETA finding of significantly larger NoGo differential current density in the N2 time-range at the ACC regions in both groups,
