Main effect of condition showed that the gain condition [3.08 (0.02)] showed significantly higher theta power [F = 73.31; p < 0.0001] than the loss condition [2.98 (0.02)] (Table 3). The region main effect revealed that theta power significantly [F = 61.07; p < 0.0001] varied across the regions: parietal [3.10 (0.02)] > central [3.04 (0.02)] > occipital [3.02 (0.02)] > frontal region [2.96 (0.02)]. Further, condition × region interaction indicated that the loss condition had higher theta power than the gain condition only in the frontal region [loss = 2.98 (0.02); gain = 2.95 (0.02); F = 6.03; p = 0.0142], while the reverse (gain > loss) was true for central [loss = 2.98 (0.02); gain = 3.10 (0.02); F = 61.11; p < 0.0001], parietal [loss = 3.02; gain = 3.17; F = 124.72; p < 0.0001], and occipital regions [loss = 2.94; gain = 3.11; F = 155.45; p < 0.0001].
