Fig. 4.

Inter-trial theta power is related to slower reaction times during conflict. (A) The theta power (group average ± SEM) during the time periods that followed low and high conflict trials is shown aligned to the onset of the arrows for the subsequent trial (t = 0). High conflict trials were followed by significantly higher theta power during the “baseline” of the next trial. Black line denotes significant time points that survived correction for multiple comparisons (p < 0.05, permutation testing). (B) A median split of the low and high conflict trials based on reaction time revealed that the slowest high conflict had higher pre-warning cue theta power than the fastest high conflict trials. (C) High conflict trial reaction time significantly correlated with the theta power that preceded the warning cue onset (t = − 1.75 to −.5, relative to arrow onset at t = 0). This effect was not present during low conflict trials. Across-subject averages of within-subject Spearman correlation coefficients (Fisher transformed) are shown for each condition (average ± SEM). * denotes significantly non-zero correlation coefficient (p < 0.05).