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The cognitive control is critical when dealing with complex environment,and the cognitive resources varied with the different uncertain levels.Recent researches have proposed that cognitive control involves two consecutive sub-processes: conflict monitoring and response implementation,which may depend on common but limited cognitive resources to allocate mental resources and prioritize the information.However,processing emotional information may also depend on the limited resources,and the resource allocation and information prioritization under the different information uncertainty and the time course of them are unclear.The present study used a majority function task(MFT)and an affective majority function task(aMFT).The arrows or emotional faces with set size of 1,3 and 5 are randomly presented at 8 possible locations arranged as an octagon centered on a fixation cross.The arrows or faces point either left or right,and are presented simultaneously for 2500 ms.Participants must indicate the direction in which the majority of the arrows or faces point.The EEGs were recorded from twenty adult volunteers(9 males)participating in the experiment with a mean age of 24.5 years at the same time.Behavior results indicated that the speed and accuracy of participants decreased with the increase of uncertainty both in MFT and in aMFT.Regressions were used to model the search method,confirming that the grouping search was a better fit than the self-terminating search for both MFT and aMFT.ERP results showed that the N200 elicited by faces are higher than that by arrows,N200 of high uncertainty are greater than that of low uncertainty,and the difference between high and low uncertainty in emotion condition was larger than that in arrow condition.The P300 was higher in lower uncertainty than in the higher uncertainty,and the arrows elicited greater P300 than emotional faces did.Our results indicate that emotional faces increase the physiological arousal and the level of conflict detection.Comparing with the lower uncertainty,individuals need more cognitive resources at the stage of conflict monitoring.In the stage of conflict control,higher uncertainty and emotional faces both increased the difficulties of conflict control.The present results suggest emotion,as same as the higher uncertainty,has the different effects on the stages of conflict monitoring and conflict control,which might depend on the rebalance of information prioritization for cognitive control.